Nuclear Medicine Procedures - Clinical Practices

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Nuclear Medicine Procedures

Clinical Practices

Contents

Radiopharmaceutical Dose Considerations 495

Bone 496

Central Nervous System (CNS) 498

Gastrointestinal 502

Three Phase Bone Scan 496Bone Scan Spot Views 496Whole Body Format Bone Scan (Single Pass Imaging) 497

Brain Imaging - Blood Brain Barrier Agents 498Brain Imaging - SPECT Perfusion Imaging 499Brain Death Evaluation 500Cerebral Spinal Flow (CSF) 500CSF Leak Determination 501

Cholescintigraphy 502Gastric Emptying Solid Phase 503Gastric Emptying and GE Reflux (Milk Study) - Liquid Phase 503Labeled Red Blood Cell Scan (GI Bleeding) 504Meckel’s Diverticulum 505Liver Fat Determination 505Liver/Spleen Imaging - 99mTc Sulfur Colloid 506Hepatic Hemangioma Imaging 507Hepatic Pump 508LaVeen Shunt Patency 508Parotid Gland Imaging 509

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Clinical Practices

Contents

Genitourinary 510

Renal Function 510DMSA Renal Imaging 511Diuretic (Lasix) Renogram 511Captopril Renal Scan for Evaluation of Renovascular Hypertension 512Testicular Imaging 513Radionuclide Cystogram 514

Lung 519

Lung Perfusion 519Lung Ventilation 520Pulmonary Aspiration 521

111In White Blood Cell Scan for Infection 518

Inflammation 517

67Ga Inflammation 517

99mTc White Blood Cell Scan for Infection 518

99mTc labeled RBC Volume Determination 515

Hematology 515

Bone Marrow 515

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Clinical Practices

Contents

Endocrine 521

Thyroid Imaging and Uptake (99mTc) 521

Thyroid Uptake and Imaging (123I) 522123I Potassium Perchlorate Washout Test 523Parathyroid Imaging 524

67Ga Tumor 525

111In Pentetreotide Imaging

Tumor 524

IIodine - 131 MIBG Imaging of Adrenergic Tumors 524

Strontium - 89 Radiotherapy 527

Miscellaneous 527

Right to Left Shunt (MAA Technique) 530Lymphoscintigraphy: Melanoma 531Shilling Test Part I 532Shilling Test Part II 534Distribution of Schilling Test Results 1981-1984 535Oldendorf Technique for Bolus Infection 537Modified Method for the In Vivo Labeling of Red Blood Cells with Technitium 538Single Photon Emission Computed Tomography 538Quality Control Procedures for Scintillation Cameras 540Quality Control Report Form 543Daily Quality Control Log for Scintillation Cameras 544

111In Pentetreotide Imaging 529

131I Whole Body or Neck with Quantitation 526

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NuclearCardiovascular Procedures

Clinical Practices

Contents

Tc-99m-MIBI Adenosine Stress 557

Tc-99m-MIBI Dipyridamole Stress 557

Tc-99-MIBI Dobutamine Stress 557

Myocardial Perfusion Imaging 550

Thallium - 201 Rest and Redistribution 550Thallium - 201 Exercise Stress with Reinjection 552Dipyridimole Thallium Stress Study with Reinjection 553Thallium Adenosine/Dobutamine Stress with Reinjection 555Tc-99m-MIBI Exercise Stress Study 555

Imaging of Ventricular Function 545

Gated Cardiac Blood Pool - Gated First Pass and Equilibrium 545Ungated First Pass Ventriculogram 547Exercise Radionuclide Ventriculogram 548Gated SPECT - Myocardium 549Gated SPECT - Cardiac Blood Pool 550

Imaging of Cellular Injury 545

Antimyosin Imaging of Infarct, Myocarditis, and Transplant Rejection 545

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Clinical Practices

Contents

Vascular Shunt Imaging 558

Stress Testing and Cardiac Emergencies 560

Right to Left Shunt: Angiographic Method 558Right to Left Shunt: MAA Technique 558Left to Right Shunt 559

General Considerations 560Patient Preparation 560Indications for Stress Testing 561Contraindications to Stress Testing 561Bruce Protocol 561Modified Bruce Protocol 562MGH Modified Bruce 562Dipyridamole-Thallium/Tc-99m-MIBI Test Protocol 562Dobutamine-Test Protocol 562Adenosine Stress Test 563

General Statement 564Non Arrhythmia Ischemia, LV Failure, or Other Medical Problems 564Arrhythmia and AV Conduction Abnormality 564

Management of Complications During Stress Testing 564

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Radiopharmaceutical Dose Considerations

Standard adult doses for specific procedures are listedin the relevant sections. Some doses (e.g.201TL) arenormally scaled within a specific range by body weight.Others may require modification as determined byspecific patient factors.

PediatricPediatric dosage can be determined in one of severalways. The easiest of these is Webster’s Rule:

Pediatric dose =age + 1age + 7

This formula may be inaccurate in infants. The mostprecise correction uses relative body surface area, esti-mated by entering height and weight into a nomogram. Aclose approximation of this can be made by using bodyweight, so that

Pediatric dose = patient weight 70 kg

In some occasions, the calculated dose may be inadequatefor image requirements. A good example of this ishepatobiliary scanning in the newborn, which may re-quire images at 24 hours after injection. The staffphysician should check the adequacy of calculated dosesin children less than one year old.

Measuring Activity and

Radiation DoseThe FDA has mandated that all labeling ofradiopharmaceuticals must be printed with “LeSystemeInternational d’Units (SI units) as soon as possible or atthe next label printing. The current unit of measure(Curie) is still in common use, but SI units will be theprimary system for measuring activity and radiation dosein the future.

Adults iThe new system was developed by the International Com-mittee of Weights and Measures and was published ints entirety in 1979. It has been adopted forradiopharmaceuticals by major nations and is currentlybeing used by most of them.

Becquerel (Bq)

In the SI System, the unit of activity is the Becquerel(Bq), which is equivalent to one nuclear transition persecond. Note that the Becquerel is a very small unit andthe curies is a very large one. The Megabecquerel (MBq)which is one billion Becquerels, or Gigabecquerels (GBq)which is one billion Becquerels.

Curies

The curies is equivalent to 37 billion transitions persecond. Because the curies is so large, we wouldcommonly use sub-units such as millicuries andmicrocuries.

Arithmetically, the following equalities exist:

1 mCi = 37 MBq

1 Rad = 0.01 GY or 1 GY 100 Rad

Possible PregnancyAll women of childbearing age must be asked aboutpossible pregnancy before they are injected with aradiopharmaceutical.

If the last menstrual period was less than one week priorto injection, it can be safely assumed that the patient isnot pregnant. If any question arises check with theNuclear Medicine staff physician.

X Adult dose

X Adult dose

=

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Three Phase Bone Scan

This study is performed to evaluate blood flow and softtissue abnormalities to augment standard bone images.

Instruments and EquipmentLarge or regular field of view gamma camera with lowenergy high resolution collimator and computer system.

Radiopharmaceutical 99mTc Methylene Diphosphonate (MDP).

Time of ImagingImmediately upon injection of radiopharmaceutical.

Dose Age +1 Age +7

Patient PreparationNone

AdministrationIntravenous injection of a small volume of 99mTc MDPusing the modified Oldendorf technique. Use 4-way stop-cock, appropriate butterfly needle and tubing, andsaline flush. If area of interest is in upper limbsinject with tourniquet only to avoid ischemic-hyperemicresponse. Do not inject in arm ofinterest. Alldynamic studies of the extremities should include bothextremities to provide a normal reference. Include amarker of the right side in the image field.

Patient PositioningFlow study is performed over the area of interestdesignated by a staff physician.

Data Acquisition

Analog - Siemens Orbiter and Body Scan Cameras:Using a 9 format acquire images every5 seconds for 9 frames.

Acquire an immediate static image for 1000Kin the 9 format.

Digital - All camerasImmediately upon injection acquire images in a128x128 matrix every 2seconds for 32

Acquire immediate static image in a 256 xmatrix for 1000K .

Image ProcessingPrepare a save screen of the flow images - 32images on one sheet of film.

Label the time of every 5th image.

Prepare a save screen of the immediate image- label: “immediate.”

Transmit all raw data and save-screens to theinterpretation room computer.

Submit films of all analog and digital imagesfor interpretation.

Special ViewsAs requested by staff physician.

Delayed ImagesAs per protocol for “Bone Scan Spot Views.”

Bone Scan Spot Views

To aid in the diagnosis and management of primary andsecondary bone disease, and to obtain higher resolutionimages than may be possible with whole body imaging.

Instruments and EquipmentLarge field of view gamma camera with high resolutionparallel hole collimator. Ultra high resolution collimatorwith MS-2.

Radiopharmaceutical99mTc Methylene Diphosphonate (MDP).

Time of ImagingNot less than 2 1/2 hours post injection.

DoseAge +1Age +7

Boneframes.

256

x 740 MBq

x 740 MBq

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Data AcquisitionAnalog - Siemens Orbiter and Body Cameras:

Acquire all spot images in the 9 format.

Acquire anterior chest image for either 750K(Orbiters), or 1100 K on all other cameras.

Record the time and acquire the remainder ofimages for the same time.

Digital - All CamerasAcquire images as described above - 256 x 256matrix.

Image ProcessingPrepare a save screen of the images using thegeneral display if digital images are needed.

Label every image.



Patient PreparationHydrate the patient with 2 glasses of water followingadministration of radiopharmaceutical. Patient is tourinate just prior to starting the imaging procedure. Havepatient remove all metal objects (jewelry, belt buckle, etc.)and any prosthesis.

AdministrationIntravenous injection.

Patient PositioningPlace patient in the supine position.

Projections: (In the following order.)1. Anterior chest2. Skull - both laterals3. Right and left anterior chest to include

shoulder and arms.4. Anterior pelvis to include iliac crests and

hips.5. Anterior tibiae to include knees6. Posterior cervical spine7. Posterior chest, thoracic and lumbar spine8. Posterior pelvis and proximal femurs

Include a marker of the right side in each image.

CommentsAdditional views may be necessary. These should be highresolution images. The images of spine, chest or pelvis,extremities and skull should be acquired for 1000Kor 15 minutes maximum. Have the patient urinateagain prior to additional pelvic view.

Whole Body Format Bone Scan(Single Pass Imaging)

To aid in the diagnosis and management of primary andsecondary bone disease. The radiolabel 99mTc MDP isabsorbed onto hydroxyapatite crystal, and concentrationon bone is directly related to regional blood flow and newbone formation.

Instruments and EquipmentSiemens Dual Headed Body Scanner with high resolutionparallel hole collimator or Siemens MS-2 with ultra-highresolution parallel hole collimator.

Radiopharmaceutical99mTc Methylene Diphosphonate (MDP).

Time of ImagingAt least 2 1/2 hours post injection.

Dose740 MBq- Adult - 70kg

Webster’s Rule - Pediatric

Patient PreparationHydrate the patient with 2 glasses of water followingadministration of radiopharmaceutical. Patient is tourinate just prior to starting imaging procedure. Havepatient remove all metal objects (jewelry, belt buckle, etc)and any prosthesis.


Patient PositioningPlace patient in supine position on table with arms closeto sides and feet together and touching. Tape feettogether lightly in order to assist patient in holding thisposition throughout the study.

Special Views As requested by staff physician.

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Analog - Siemens Dual Headed Body Scanner:

Acquire analog images in the whole body mode.

Scan Speed Determination (Siemens BodyScan):

Scan patient at 224 cm/min.

Calculate total counts in anterior image.

Multiply results by 224, divide by desired total I.D. (300,000 to obtain correct scan speed in cms/min which is around 14 cm/min.

Carefully scan, contouring anterior detector. Note: Do NOT exceed 18cm/min.

Digital - Siemens Dual Headed Body Scanner or MS-2:

Acquire analog images in the whole body mode.

Scan Speed Determination - As above with bodyscanner.

When using MS-2 with ultra-high resolutioncollimator: mutiply scan speed by 0.6.

Always use auto-contour with MS-2. (See below.)

Special Views(Total body bone scans may require extra views)

Analog - Siemens Orbiters and Body Cameras:

Acquire analog extra views in 9 format for 750Kon the Siemens orbiter camera or 1100K on allother cameras.

Digital - All Cameras:

Acquire images as described above - 256 x 256matrix.

Image ProcessingPrepare a save screen of the whole body usingthe dual intensity display.

Prepare a save screen of the spot images usingthe general display.

Label every image. Write scan speed on films.


Submit films of all analog and digital images forinterpretation.

ProjectionsAnterior and Posterior

Data Acquisition

Brain Imaging Blood Brain Barrier Agents

Normally 99mTc DTPA and glucoheptonate (GHA) do notcross the blood brain barrier (brain capillary endothelium).The BBB is disrupted in most inflammatory,ischemic, neoplastic ortraumatic cerebral disorders,resulting in focal accumulation of the radiolabel.99mTc DTPA and GHA have been used in the past asbrain imaging agents because of rapid renal (and blood)clearance which results in a potentially hightarget/non-target ratio.

Instruments and EquipmentRegular field or large field of view gamma camera withlow energy all purpose collimator and computer system.A converging collimator may be needed for special views.

Radiopharmaceutical99mTc DTPA or Glucoheptonate.

Time of ImagingDynamic images recorded immediately upon injection.

Delayed images are recorded at least 3 hours later.

Dose740 MBq - Adult



AdministrationIntravenous injection of a small bolus using modifiedOldendorf technique. Set up 4-way stopcock, appropri-ate butterfly needle and tubing, and saline flush.

Patient PositioningPatient should be positioned so that a minimal amountof facial activity is present in the field of view.

Central Nervous System(CNS)

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ProjectionsFlow study is usually recorded in the anterior projection.Static Images:

AnteriorPosteriorRight lateralLeft lateralVertex

Data AcquisitionDigital

Flow Images:Acquire images at a 3 second frame rate forone minute in 128x 128 matrix.

Static Images:Acquire an immediate 500K static in 256 x 256matrix. Usually anterior view.

Delayed Images:(Minimum of 3 hrs post injection).Acquire static images in 256 x 256 matrix.

Image ProcessingPrepare a save screen of the images using thegeneral display.

Label every image.



CommentsPatient condition or the nature of the suspected diseasemay require modification of technique. Delayed imagesbeyond 3 hours post injection may be indicated.

Brain ImagingSPECT Perfusion Imaging

Following intravenous injection, 99mTc-HMPAO(exemetazime) and 99mTc-ECD (bicisate) cross the blood-brain-barrier and accumulate in the brain. Abnormalitiesassociated with increased or decreased cerebralperfusion may be shown as corresponding regionsof abnormal tracer deposition. SPECT imaging is neededto demonstrate these subtle differences, and to providemeaningful anatomic assessment.

Instruments and EquipmentMS-2 with fan beam collimator.

Radiopharmaceutical740 Mbq (20 mCi) 99mTc-HMPAO (adult dose) or740-1110 MBq (20-30 mCi) 99mTc-ECD.

Time of ImagingHMPAO- 20 minutes after injection.ECD- 30-60 minutes after injection.

Patient PreparationNone. The injection is ideally given through an indwell-ing venous line in a quiet, dimly-lit room.

Image AcquisitionOnly SPECT images are acquired, using 360o rotationwith 2 heads, 96 views per head, 15 seconds per view.

Image AnalysisReconstruct tomographic images using attenuationcorrection. Photograph SPECT images in trans-verse, saggital, and coronal planes and saveSPECT reconstruction files to disk.

CommentsThe preparation and use of 99mTc-HMPAO imposesseveral special considerations. The presence of anyoxidant in the 99mTc-pertechnetate generator eluate usedto formulate the HMPAO complex may prevent adequatelabeling. To avoid this problem, the generator must havebeen eluted within 24 hours prior to the elution usedfor kit formulation.

Once formulated, the 99mTc-HMPAO complex is unstable.The primary complex formed converts with time to adifferent secondary complex that is less lipophilic, andthus unable to cross the blood-brain-barrier. In onsequence, 99mTc-HMPAO must beinjected within 30minutes of formulation. This means that each dosemust be prepared while the patient is waiting, and thatQC procedures must be completed expeditiously. Thesefactors do not apply to ECD.

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Brain Death Evaluation

Cerebral perfusion ceases upon death of cerebral tissue.The best radionuclide evaluation of intracranialperfusion is obtained using 99mTc HMPAO (exameta-zime).

Instruments and EquipmentRegular field of view gamma camera, all purpose lowenergy collimator, computer.

Radiopharmaceutical99mTc HMPAO.

Time of ImagingImmediate.

Dose740 MBq.

Patient PreparationNone required for HMPAO.

AdministrationIntravenous injection

Patient PositioningStatic images in the anterior and lateral projections.

Analog: None

Digital - Technicare Portable CameraStatic Imaging:

Acquire 1 immediate 500K static in quadrantformat (128 x 128) e.g. SAQ C, 500 K, Q1 inthe anterior and lateral projections.

Acquire additional images based on instructions by the staff physician.

Digital - Siemens Orbiter Camera

Static Imaging:

Acquire 1 immediate 500K anterior and lateralmages in 256 x 256 matrix.

Acquire additional images based on instructions by the staff physician.

Image ProcessingConvert technicare images to Siemens formatand transmit all images to the interpretationroom computer.

Photograph all images andsubmit to staffphysician for interpretation.

Reference SH Tsai, et al, JAMA 248:591-592,1982 (7/96).

CSF is produced in the brain’s lateral ventricles, and re-absorbed mostly along the superior sagittal sinus. Insome patients with CSF shunts or who are receiving in-trathecal chemotherapy, the pattern of CSF flow may beimportant to document.

Instruments and EquipmentLarge field of view gamma camera with medium energyparallel hole collimator. Set up the camera for imagingIndium-111 as follows:

171 keV photopeak with a 30% window


Radiopharmaceutical111In DTPA.

Time of ImagingImmediate; delayed images at 2-6 hours may benecessary.

Dose18.5 MBq - Adult



AdministrationIntrathecal (spinal) injection of radio-pharmaceutical.This injection is performed by the referring physicianand requires an informed consent.

Cerebral Spinal Fluid(CSF)

(Informed Consent Required)

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Note: In the case of CSF shunt patients specialinjections may be required. Check with staff physician.If a CSF specimen is needed, make sure thatCSF is withdrawn prior to injection of the radiopharma-ceutical.

Patient PositioningProjections: Anterior; Posterior; Right & left lateralprojections.

Data AcquisitionSiemens OrbiterAnalog:

Acquire 500K or 10 minute images in the 4 format.

Digital: Acquire digital images in a 256 x 256 matrix for backup.

Special ViewsSpecial views may be required in the case of CSF shuntpatients.

Image ProcessingTransmit all digital images to the interpretation room computer.

Photograph all images and submit to staffphysician for interpretation.

CSF Leak Determination

Normally there is no CSF present in the nose or ears. Thedetection of significant radioactivity in those areas afteran intrathecal injection of 111In DTPA is characteristic ofa CSF leak.

Instruments and EquipmentLarge field of view gamma camera with medium energyparallel hole collimator. Setup the camera for imaging111In as follows:



Radiopharmaceutical111In DTPA.

Time of Imaging4 hours post injection.

Dose18.5 MBq - Adult


Patient PreparationNasal pledgets are to be weighed and placed prior toinjection of the patient. Pleglets are placed by an ENTphysician. This should be arranged by the physicianrequesting the study.

AdministrationIntrathecal (spinal) injection of radiopharmaceutical.This injection is performed by the referring physician andrequires an informed consent.

Patient PositioningAnterior; Posterior; Right & left lateral projections.

Data Acquisition

Siemens Orbiter

Analog:Acquire 500K or 10 minute images in the 4format.

Digital:Acquire digital images in a 256 x 256 matrixfor backup.


Image ProcessingTransmit all digital images to the interpretation room computer. Photograph all imagesand submit to staff physician for interpretation.

CommentsTwo blood samples are withdrawn from the patient inred top tubes, the first15 minutes following injectionand the second sample at the time of imaging (approxi-

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mately 4 hours post injection). Plasma samples on thetwo blood samples are separated from whole bloodby centrifugation. Retain one ml of plasma from bothsamples for counting determination. Nasal pledgets areremoved at the time of imaging and placed in appropriatecounting vials, after weighing again. Count plasmasamples and nasal pledgets in a well counter at theappropriate photopeak setting for 15 minutes per sampletimes 2.

NOTE: Weigh both before and after insertion in appropri-ate counting vials!

ReferenceRadionuclide cisternography: normal values for nasalsecretion of intrathecally injected Indium-111 DPTA. JNuclear Med 1973; 14:933-934.

Gastrointestinal

Cholescintigraphy

The iminodiacetic agents are excreted via hepatocytesandrapidly cleared into gut. In most patients with acutecholecystitis, the cystic duct is completely blocked; thus,there is no demonstration of the gallbladder. This testmay also be used to evaluate for suspected bile leak,biliary atresia, and liver transplant viability.

Instruments and EquipmentLarge field of view gamma camera equipped with lowenergy parallel hole collimator and computer system.

Radiopharmaceutical99mTc Disofenin (DISIDA) or mebrofenin.

Time of ImagingImmediately post injection.

Dose37 MBq

Patient PreparationNPO prior to study for at least 4 hours but not more than24 hours. If the patient has fasted for more than12-24hours, administer sincalide in a dose of 20ng/kg. This is

given as a slow IV injection over at least 3 minutes toreduce potential GI side effects and to maximize itspharmacologicaleffect. Wait30-45minutes beforeinjecting the radiopharmaceutical. Sincalide is availablein the Radiopharmacy as 5 mcg lyophilized vials.

Reconstitute the vial with 5.0 ml of sterile water forinjection and use the following formula:

Patient weigh in kg. X (0.02) = ml to draw

AdministrationIntravenous injection of radiopharmaceutical.

Patient PositioningProjections: Anterior

Data AcquisitionAnalog:

Need to be determined by staff physician.

Digital:Starting immediately after injection acquire30 second images in 128 X 128 matrix for 45minutes.

If the gallbladder has not been demonstratedby that time, intravenousmorphine will typicallybe given in a dose of 0.4 mg/kg with imagingfor an additional 45 minutes after morphineadministration.

In some cases, additional disofenin will beinjected. Write all image data to floppy diskand submit along with analog images forinterpretation.

Image ProcessingPrepare a save screen of every 5th image forthe firsthour of imaging. The format of savescreens for delayed images will be determinedby the staff physician. Transmit all images tothe interpretationroom computer and submitphotographs of all save screens for analysis.

Special ViewsIt may be necessary to obtain posterior andright lateral views to triangulate the gallblad-der, and separate it from the duodenum.

NOTE: If bile leak is suspected, delayed images atseveral hours post-injection may be needed.

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Gastric Emptying Solid Phase

This study is performed to assess gastric emptying time.

Instruments and EquipmentLarge field of view gamma camera with a low energyparallel hole collimator and computer system.

Radiopharmaceutical99mTc sulfur colloid.


Dose18 MBq - Adult

Patient PreparationPatient should be fasting for approximately 8 hoursprior to the study.

Administration18 MBq of 99mTc sulfur colloid is mixed withscrambled eggs or an egg salad sandwich and fed tothe patient.

Patient PositioningAnterior and posterior projections.


Not required

Digital:Acquire 1 minute anterior and posterior images

in a 256 x 256 matrix at the following times: immedi-ately after ingestion of meal, 0, 20, 40, 60, and 90 min-utes. The patient may get up between images.

Image AnalysisDraw regions of interest around the stomach in all images,determine the number of counts in each image, decaycorrect the delayed images to zero time andcalculateda geometric mean count at each time.

Calculate %emptying at 20, 40, 60, and 90 minutes.

Prepare a labeled save screen for the 5 images andphotograph. Submit all digital data and photographs tothe interpretation room for analysis.

CommentsDrape the patient with absorbent paper (chux) andhave patient wear disposal globes while eating meal toprevent contamination.

Have an emesis basin close at hand for those patientswho are known to have severe intolerance to solid food.If initial images show residual activity in the esophagus,have the patient drink a small amount of water.

Gastric Emptying and GE Reflux (Milk Study) - Liquid Phase

To ascertain rate of gastric emptying and detectgastroesophageal reflux, and presence of pulmonaryaspiration. This is usually performed in children.

Instruments and EquipmentGamma camera with low energy all purposecollimatorand computer system.


DoseDetermine the usual quantity of formula that the childreceives at a regular feeding and add 0.1 MBq (2.5 mCi)or 99mTc sulfur colloid/ml formula (do not exceed 12MBq). Record the time required to ingest the formula.

Time of ImagingImmediately post ingestion.

Patient PreparationPatient must be fasting for previous normalintervalbetween feedings. (e.g. if fed 6 times daily, should befasting for 4 hours).

AdministrationSee Dose.

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Patient PositioningAnterior supine projection to include entire abdomenand chest.


None required.

Digital:Acquire serial 30 second images in a 128 x 128matrix for 1 hour.

Image AnalysisDraw a region of interest around the stomach anddetermine the number of counts in the 0, 20, 40, and 60minute images. Decay correct the delayed images tozero time and calculate % emptying at 20, 40 and 60minutes. Prepare a labeled save screen for the 0, 20,40 and 60 minute mages and photograph. Submit alldigital data and photographs to the interpre-tation room for analysis.

Special ViewsAs determined by staff physician.

CommentsIf the study is performed to evaluate for possible pulmo-nary aspiration, the dose is usually administered in theevening, with 10 minute anterior and posterior images ofthe chest performed the following morning. In evalua-tion of an infant, the dose can be administered in themorning and imaging performed in the afternoon.

Labeled Red Blood Cell Scan (GI Bleeding)

This study is performed to find a specific bleeding site inthose patients who have active gastrointestinalhemorrhage. Patients are often referred by angiography,who will be prepared to perform an angiogram if ableeding site is detected by our study. Since 99mTc RBC’sare an intravascular agent, extravasation into the gutwill be detected by this method.

Instruments and EquipmentLarge field of view gamma camera with low energyparallel hole collimator and computer system.

Radiopharmaceutical99mTc labeled RBC’s.

Note: RBC labeling is performed with the Ultra Tagin vitro labeling kit.

DoseAge +1

Age +7 x 740 MBq


AdministrationIntravenous injection of labeled RBC’s.


Patient PositioningAnterior supine abdomen from the pubic symphysis to hediaphragm to include inferior portion of the heart in theupper margin of the field of view.

Data Acquisition

Analog:Not required

Digital:Acquire serial 1 minute images in a 64 x 64matrix.

Image AnalysisPrepare a labeled save screen of every 5th image andphotograph. Submit all digital data and photographs tothe interpretation room for analysis.

CommentsIf bleeding is not detected on the initial study, the pa-tient may be recalled for delayed imaging. Patient mayalso be reimaged if there is some clinical evidence of hem-orrhage in the interval. Image acquisition parameterswill depend on the time elapsed since initial labeling.

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Meckel’s Diverticulum

To aid in the detection and diagnosisof Meckel’s diver-ticula. 99mTc pertechnetate is normally excreted by gastric mucosa. Since over 90% of bleeding Meckel’sdiverticula contain ectopic gastric mucosa, this test is asensitive means for detection.

Instruments and EquipmentLarge field of view gamma camera with lowenergyarallel hole collimator and computer system.

Radiopharmaceutical99mTc Pertechnetate.

Time of ImagingBeginning immediately before injection.

DoseAge +1

Age +7 x 740 MBq

Patient PreparationPatient must be fasting from midnight the previousnight with nothing by mouth except water.

AdministrationIntravenous injection of radiopharmaceutical is performedwith the patient in position under the camera.

Patient PositioningAnterior supine projection to include entire abdomenwith the pubic symphysis at the lower margin of thecamera field.


Not required.

Digital:Acquire serial 1 minute images in a 128 x 128matrix for 1 hour.

Image AnalysisPrepare a labeled save screen of every 5th image andphotograph. Submit all digital data and photographs tothe interpretation room for analysis.

Note: This procedure is done routinely for indicationsthat are not specifically listed in the manufacturer’spackage inserts. The choice of the radiopharmaceuticaland the dose for each procedure described in this Proce-dure Manual is made by the physician staff of thisNuclear Medicine Division, in order to acquire the bestimaging results while complying with MGH Isotope and/or Pharmacy Committee guidelines. The name of thenuclear medicine physician ordering any test that is listedhere is maintained in the files of the radiopharmacy withthe data on the patient and radiopharmaceutical.

Liver Fat Determination

The partition coefficient of xenon is higher in fat than inother tissue. Following inhalation, xenon enters the cir-culation, is distributed in the body tissues, and clearsfrom those tissues when xenon administration ceases.Xenon retention correlateswith liver fat (triglyceride)content, which is increased in diabetics, alcoholics, andobesity.

Instruments and EquipmentLarge field of view camera. All purpose collimator andcomputer.

Radiopharmaceutical133Xe

Dose370-740 MBq


Administration133Xe via closed system for 5 minutes.

Patient PositioningSupine anterior, include liver and lower lung.

Data Acquisition

Analog:Not required

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Digital:Serial 15 second images in a 128 x 128matrix, extending from initial inhalationthrough 15 minutes of washout.

Special ViewsNone

Image AnalysisDetermine T1/2 of washout from the liver from a regionof interest drawn around a portion of liver away fromlung base.

CommentsT1/2 greater than 2.0 min. correlates with increasedtriglyceride (> 100 mg/gm) in liver fat.

Note:This procedure is done routinely for indications that arenot specifically listed in the manufacturer’s packageinserts. The choice of the radiopharmaceutical and thedose for each procedure described in this Manual is madeby the physician staffof the Division of NuclearMedicine, in order to acquire the best imaging resultswhile complying with MGHIsotope and/or PharmacyCommittee guidelines. The name of the nuclear medicinephysician ordering any test that is listed here is main-tained in the files of the radiopharmacy with the data onthe patient and radiopharmaceutical.

ReferencesInt J Nuclear Med Bio 9:17-23, 1982.

Liver/Spleen Imaging99mTc Sulfur Colloid

The liver and spleen contain large numbers of evenlydistributed reticuloendothelial cells, which trap the99mTc sulfur colloid. The procedure is intended primarilyto be used for detection (or monitoring) of disorders whichdisrupt the organ architecture. Functional abnormalitiesmay be implied by the relative uptake of each organ,especially in comparison to the other two large REScontaining organs (lung and bone marrow).

Instruments and EquipmentLarge field of view gamma camera with low energy highresolution.


Time of Imaging15 minutes post injection.

Dose148 MBq - Adult




Patient PositioningAcquire liver images in the following sequence:

Ant (Marker), Ant , RAO, RL, Post , LL

Data Acquisition

Analog:1000 K per image

Digital:Acquire backup images for 1000K in a 256 x256matrix.

Image AnalysisPrepare a labeled save screen of digital data and photo-graph. Submit all digital data, analog data and photo-graphs to the interpretation room for analysis.

CommentsIf the spleen is being specifically evaluated, such as forinfarct or trauma, obtain the following:

LAO 30o, LAO 60o, LPO 30o, LPO 60o.Record data in digital format.

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Hepatic Hemangioma Imaging

Hepatic hemangiomas are low flow lesions with increasedvascular volume, which are “cold” on a 99mTc sulfurcolloid study, but which show progressive 99mTc RBCaccumulation over a 60 minute period.

Instruments and EquipmentLarge field of view gamma camera with low energy par-allel hole collimator andcomputer system.

Radiopharmaceutical(1) 99mTc-SC if liver/spleen scan has not already

been obtained.(2) 99mTc labeled RBC’s.

Time of ImagingObtain 99mTc-SC scan first, and then 99mTc-RBC scan.

Dose37 MBq 99mTc-Sulfur colloid (SC); 740 MBq 99mTc-RBC.

Patient PreparationIf patient has not had a SC liver/spleen scan, obtain ant,RAO, (R) lateral and posterior views of liver at 15 minafter injection of 27 MBq of SC.

Label the patient’s blood using the modified in vivo tech-nique for labeling RBC’s with 99mTc. (This is the sameprocedure that is used forgated cardiac blood poolimaging.)

AdministrationIntravenous “bolus” injection of radio pharmaceutical.Start imaging immediately.

Patient PositioningFlow study images should be acquired in the projec-tion that best demonstrates the abnormality(check 99mTcSC liver scan, ultrasound or CT findingswith staff physician).


Not requiredDigital:

Acquire flow study in a 128 x 128 matrix at a4 second frame rate 16 frames.

Acquire static images in a 256 x 256 matrixfor 1000k in the following projections:ANT, RAO, R lateral, and posterior.

Immediately following completion of planarimages, acquire SPECT images of liver. Bothplanar and SPECT images are repeated 1-2hours later.

Image AnalysisPrepare a labeled save screen of the flow and staticimages and photograph. Submit all digital data andphotographs to the interpretation room for analysis.

Special ViewsAdditional views may be needed to delineate question-able abnormal areas. It may be necessary to performSPECT in some patients.

Note: This procedure is done routinely for indicationsthat are not specifically listed in the manufacturer’s pack-age inserts. The choice of the radiopharmaceutical andthe dose for eachprocedure described in this Manual ismade by the physician staff of the Nuclear MedicineDivision, in order to acquire the best imaging results whilecomplying with MGH Isotope and/or Pharmacy Commit-tee guidelines. The name of the nuclear medicine physi-cian ordering any test that is listed here is maintained inthe files of the radiopharmacy with the data on thepatient and radiopharmaceutical.

Hepatic Pump

Intra-arterial chemotherapy of intrahepatic tumors is givenvia an indwelling catheter, or hepatic pump. This testconsists of injection of MAA to assess the distributionof flow from the pump.

Instruments and EquipmentLarge field of view gamma camera with lowenergy highresolution parallel hole collimator and computer system.

Time of ImagingImmediately upon injection.

Radiopharmaceutical 99mTc MAA, 99mTc Sulfur Colloid.

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CLINICAL PRACTICES

Dose37 MBq of 99mTc MAA in 2 ml volume; 37 MBq of99mTc sulfur colloid.

Administration1st injection:

Inject 99mTc-MAA in 2 ml of volume via the pump.

2nd injection:

Inject 99mTc sulfur colloid intravenously.

Patient PositioningAcquire all images in the anterior supine position.


Not necessary

Digital:After injection of 99mTc- MAA acquire a500K image in a 256 x 256 matrix.Note: Record the time it takes to acquire thisimage.

Fifteen munutes after IV injection of 99mTcsulfur colloid, acquire a second image in a256 x 256 matrix for the same time as the99mTc- MAA image.

Image AnalysisUsing the image calculator subtract the 99mTc- MAAimage from the 99mTc- SC image + 99mTc- MAA. Pre-pare a labeled save screen of the three images. andphotograph. Submit all digital data and photographs tothe interpretation room for analysis.

Note: This procedure is done routinely for indicationsthat are not specifically listed in the manufacturer’s pack-age inserts. The choice of the radiopharmaceutical andthe dose for each procedure described in this Manual ismade by the physician staff of the Nuclear MedicineDivision, in order to acquire the best imaging results whilecomplying with MGH Isotope and/or PharmacyCommitteeguidelines.The name of the nuclearmedicine physician ordering any test that is listed hereis maintained in the files of the radiopharmacy with thedata on the patient and radiopharmaceutical.

LaVeen Shunt Patency

To assess the patency of a LaVeen peritoneal-jugular shuntby evaluating clearance of activity through the shuntfollowing the introduction of tracer into the peritonealcavity.

Instruments and EquipmentLarge field of view gamma camera with low energy par-allel hole collimator and computer system.

Radiopharmaceutical99mTc MAA

Dose100 MBq

TechniqueThe course of the subcutaneous shunt tubing inthe lateral abdomen and chest is located.

Using sterile technique, a 20 gauge needle isintroduced into the peritoneal cavity on thecontra-lateral side with the use of 1% lidocaineanesthesia.

Informed consent must be obtained for this pro-cedure. The radioisotope is then introduced intothe peritoneal cavity. The patient is then rolledside to side and asked to take several deepbreaths.

ImagingImmediate anterior image of the abdomen for 300K(256 x 256 matrix).

Subsequent 300K (256 x 256 matrix) anterior imagesof chest to include the upper abdomen and position ofthe shunt tubing along the lateral chest wall every 5minutes until activity is visualized in the lungs.

If no activity is identified in the lungs during the initial45 minutes, delayed images for up to 4 hours may berequired.

Image AnalysisPrepare a labeled save screen of all the images andphotograph.

Submit all digital data and photographs to the interpre-tation room for analysis.


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Note: This procedure is done routinely for indicationsthat are notspecifically listed in the manufacturer’s pack-age inserts. Thechoice of the radiopharmaceutical andthe dose for each procedure described in this ProcedureManual is made by the physician staff of the NuclearMedicine Division, in order to acquire the best imagingresults while complying with MGH Isotope and/orPharmacy Committee guidelines. The name of the nuclearmedicine physicianordering any test that is listed hereis maintained in the files of the radiopharmacy with thedata on the patient and radiopharmaceutical.

ReferenceClin Nucl Med 4:447-450;451-454, November 1979.

Parotid Gland Imaging

To aid in the assessment of tumors or nodules of theparotid glands.

Instruments and EquipmentRegular field of view gamma camera and computersystem.

Radiopharmaceutical99mTc Pertechnetate

Time of ImagingImmediately since flow study is needed.

Dose185 MBq - Adult



AdministrationUsing the modified Oldendorf technique inject a smallbolus of activity for the flow study. Note: Use a 4-waystopcock and appropriate needle, tubing and saline flush.

Patient PositioningPlace patient in supine position with head and neckhyperextended.

Acquire flow and static images of the head and neck.


Not required

Digital:

Acquire an anterior flow study in a 128 x 128matrix at a framerate of 30 seconds per framefor 300 seconds (10 frames).

Acquire anterior, right and left lateral staticviews of the head (128 x 128 matrix) at a framerate of 60 seconds per frame for 600 seconds(10 frames).

After acquiring initial static images give lemonand repeat above static acquisition.

Image AnalysisSum the initial and delayed static images using theimage calculator and prepare labeled save screens for allthree sets of images.

Submit all digital data and photographs to the interpre-tation room for analysis.

Special ViewsAs directed by staff physician.

CommentsGive the patient 500 mg of KCl0 4 following the study.

ReferenceRadionuclide Salivary Gland Imaging: Sem Nuclear MedXl:258-265, 1981.

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CLINICAL PRACTICES

Genitourinary

Allows relative quantitation of perfusion and excretoryfunction of kidneys. DTPA measures glomerular filtra-tion rate, while MAG3 shows mainly tubular function.

The initial arrival time of the tracer bolus relates to renalblood flow. The transit through the kidneys reflectscortical and tubular function, and the eventual clearancefrom the collecting system reflects renal pelvic andureteral patency.

99mTc- glucoheptonate is rarely employed, but shows amore copmplex clearance with partial tubular binding.

Instruments and EquipmentPreferred instrument Orbiter or MS-2 with all purpose orhigh resolution collimator and interfaced computer.

On rarer occasions, a portable scan may be performedusing a diverging collimator in adults.

Radiopharmaceutical370 MBq (10mCi) Tc99m MAG3 or370 MBq (10 mCi)DTPA.

To localize the kidneys and vascular structures (aorta) ina portable study, the patient should be pre-injected with37 MBq DTPA.

In a patient with renal failure use the aorta as areference point.

Time of ImagingImmediate

Patient PreparationHydrate patient with 12 ounces of water 30 minutesprior to study; have the patient void prior to injection.

Image AcquisitionStandard images are obtained in the posterior position,centered just inferior to the kidneys.

In renal transplant patients, anterior images centered overthe iliac fossa are acquired.

In a portable study, position the patient in one of thelateral decubitus positions and approach the patient withthe camera from the patient’s back.

Dynamic images are recorded in 128 x 128 matrix at2 seconds per frame for 32 frames, followed by30 seconds per frame for 64 frames.

Image AnalysisSelect “MGH Renal” from the processing protocols.

Define Composite ImagesThe default imaging range is 1 to 3 minutes. To selectanother range, choose “Time Range” from the compos-ite menu and enter the starting and ending points. Oncedefined, click DONE to continue.

Define RegionsComplete dialog boxes is appropriate. Draw manualregions of interest around the kindeys by escaping whenprompted to select an automated elliptical region ofinterest. Draw semi-circular background regionssurrounding and immediately adjacent to the lowerportions of each kidney.

Define Start PointOnce the regions are defined, the perfusion curves areshown on the left. The triangular marker on the x-axisof the curve should be dragged to the position where theaortic activity starts to increase. This processing step isimportant because this is the time used as the startingpoint for all calculations (Tmax, T1/2).

ResultsThe first RESULT page (curves) show two graphs: theleft graph shows perfusion data and the right graph showsclearance data.

If the aortic curves extend beyond the y-axis on the left(perfusion) time-activity curve, select the graph by click-ing on the margin. Select “options” and click on the y-axis label. Select “range set automatically” from thedisplayed menu.

The right graph displays four curves, with both wholekidney and “cortical” activity for each kidney. It may bedesirable to eliminate some of these curves, as in adiuretic study.

To delete a curve, first select the graph by clicking on themargin. Next, select the curve by clicking on the appro-priate symbol in the small right window. Finally, click on“curve” from the “Display Analysis” and select the op-tion “delete curve.”

The last RESULT page shows the half time analysis forkidney clearance. The menus on the left give fiveoptions (left kidney, left cortex, right kidney, rightcortex, done).

Renal Function

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To calculate the T1/2 for any of the regions, click on theRO1. The graph on the right will display the curve forthe appropriate region. Drag the left triangular markeron the x-axis to the position of maximum activity forthat curve.

For a diuretic renogram, drag the triangle to the time ofdiuretic injection (20 minutes). Next, drag the righttriangle to the end of the curve. The program will thendisplay a best fit curve superimposed on the original data.You are then given the option to accept or change thecurve fitting. Repeat this process for each T1/2 desired.

Image and Data DisplaySelect the MGH Renal Display application from theProcessing Protocols. The program will display 32dynamic flow images as well as six composite clearanceimages every 5 minutes for 30 minutes.

If additional images were obtained beyond 30 minutes, itis necessary to create a save screen manually for thedelayed images.

CommentsIn selected patients, delayed images may be required.

99mTc glucoheptonate may be used at the discretion ofthe staff physician in cases involving specific questionsabout renal structure.

The radio-pharmaceutical dose is 370 MBq (10 mCi).

Imaging is similar to MAG 3 or DTPA, with additionalimages at 2 hours as determned by the physician. Theselate images will typically consist of posterior, RPO, andLPO images. Initial data and processing is as per thestandard renal protocol.

DMSA Renal Imaging

Following intravenous injection, 99mTc-DMSA is boundto plasma proteins, and accumulates in the renal cortex.There is very little excretion in the urine.

At 3 hours post injection, roughly 40% of the injecteddose remains in the kidneys. This allows anatomicdefinition of the renal parenchyma not easily afforded byother renal scanning agents.

DMSA has been most widely used in the evaluation ofpyelonephritis and post-infectious scarring in children.

Instruments and EquipmentMS-2 with all purpose or high resolution collimator; smallfield of view camera with pinhole collimator.

Radiopharmaceutical185 MBq 99mTc-DMSA (adult dose).

Time of imaging2-3 hours post injection; no initial images are required.


Image AcquisitionPinhole images of the kidneys in posterior, RPO, andLPO projections for 5-10 minutes each, depending onthe patient’s ability to cooperate.

Standard parallel collimator posterior image of thekidneys acquired for 10 minutes or 1000K in a 256x256matrix size.

SPECT acquisition using 360o rotation with 2 heads,96 views per head, 15 seconds per view.

Image AnalysisPrepare labeled save screen of pinhole and standardplanar images. Reconstruct and photograph SPECTimages in transverse, saggital, and coronal planes andsave SPECT reconstruction files to disk.

Diuretic (Lasix) Renogram

Evaluation of hydronephrosis, in particular to differentiatea dilated, nonobstructed system from a dilated,obstructed renal collecting system.All renal scans requested to “rule out obstruction” arepotential Lasix studies. Check with staff physician todetermine if a Lasix study is indicated.

Instruments and EquipmentOrbiter or MS-2 camera with all-purpose or highresolution collimator and interfaced computer.

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CLINICAL PRACTICES

Radiopharmaceutical370 MBq (10 mCi) 99mTc-MAG3 by bolus injection;alternatively, 370 MBq of 99mTc-DTPA may be used.


Patient PreparationGive patients (other than infants) approximately 12 ozs.of fluid to drink 30 minutes prior to the study.

Have nurse insert a Foley catheter. This will remain inplace unclamped during the study.

Usually all nephrostomy or other external renal drainingdevices (other than the Foley) should be clamped; checkwith nuclear medicine physician monitoring study.

Image AcquisitionAcquire posterior images centered just below thekidneys in 128 x 128 matrix size.

Dynamic images are recorded at 2 sec/frame x 32 frames,followed by 30 second images x 128 frames.

For a Lasix study, imaging is carried out for onehour, not the 30 minutes of a standard renal scan.

Lasix (0.3 mg/kg) is typically injected intravenously 20minutes after radio-pharmaceutical injection.

Image AnalysisSplit function quantitation and time-activity curves aregenerated as for the standard renal scan, except thatthe clearance phase time activity curves should be drawnto include the entire kidney including the renalpelvis but excluding the ureter.

To avoid confusion, delete the clearance curves for the“cortical” regions.

When generating the T1/2 data, be sure to drag the lefttriangle on the x-axis of the clearance curve to the timethat Lasix was given (typically 20 minutes) so that anadequate evaluation of diuretic washout is calculated.

Label the frame corresponding to the time at which Lasixwas given.

CommentIn some cases, imaging beyond one hour may be needed.The normal half-time for clearance of tracer from thekidney ROI is10 minutes or less. A time greater than20 minutes is abnormal, while 10-20 minutes isconsidered indeterminate.

By decreasing glomerular filtration in the stenotickidney, an ACE inhibitor such as captopril diminishesexcretion of the tracer in that kidney. This creates orincreases a functional asymmetry between the normaland abnormal kidneys.

The study is probably of lesser value in assessingbalanced bilateral renal artery stenoses, because the lackof asymmetry may render these cases inapparent on thescan.

The study is performed after oral administration of anACE inhibitor. In selected instances, it may be repeatedon a different day without the use of ACE inhibitor(baseline study), should the captopril scan show asignificant asymmetry in function.

If a baseline study is to be performed, it should bedelayed for at least 48 hours to ensure that the pharma-cologic effects of captopril have worn off.

Instrument and EquipmentOrbiter or MS-2 with all purpose or high resolutioncollimator and interfaced computer.

Radiopharmaceutical370 MBq (10 mCi) Tc99m MAG3 or 370 MBq (10mCi) DTPA.


Patient Preparation

Withhold ACE InhibitorsIf possible, ACE inhibitors should be withheld prior to thestudy (captopril- 2 days, enalopril- 3 days, lisinopril- 4days). This allows the physiologically simplest condition,mirroring the validation of captopril imaging.

In some patients, it is not feasible to withhold ACEinhibitors prior to the study. In that case, the SNMconsensus position paper suggests that imaging proceedafter an additional dose of captopril.

There is a suggestion that the sensitivity of the exam inthis setting may be compromised slightly.

Withhold DiureticsWithhold diuretics for several days prior to imaging iffeasible.Diuretics may make the patient more prone tohypotension. There is controversy about whether or notdiuretic use decreases thesensitivity of the study.

Captopril Renal Scan for Evaluation of

Renovascular Hypertension

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NUCLEAR MEDICINE

If diuretics are not withheld, hydration becomes even moreimportant than would otherwise be the case.

All patients should be hydrated with 1 1/2 to 2 glassesof water or other fluid 30-60 minutes prior to the study.

Patients should refrain from eating solid food for 4 hoursprior to the exam in order to ensure absorption of thecaptoprildose.The patient’s baseline blood pressure should be checkedand recorded before taking any further action. If the BPis not elevated, consult with the staff physician abouthow to proceed.

An IV line should be placed (butterfly is OK) in theelderly, in patients with a history of heart disease, stroke,or TIA’s. This is not necessary in most younger patients.

Captopril is given 25 mg PO, and serial BP measurementsrecorded every 15-20 minutes for one hour. The drop inBP after this dosage is usually modest.

More significant hypotension can usually be managedwith recumbency and IV initial value and they should beasymptomatic before being allowed to leave the section.

Alternatively, enalaprilat may be given IV as a 5 minuteinfusion, monitoring blood pressure and proceeding asbelow.

At 1 hour following captopril administration, a final BPshould be checked and the patient should void beforebeginning imaging.

Image AcquisitionImages are obtained in the posterior position, centeredjust inferior to the kidneys. Dynamic images are recordedin 128 x 128 matrix at 2 seconds per frame for 32 frames,followed by 30 seconds per frame for 64 frames.

Image AnalysisAs per the “Renal Function” protocol 6.1.

CommentsThe interpretive criteria for abnormal studies differbetweenMAG3 and DTPA:

MAG3Unilateral parenchymal retention (not to be confused withureteral obstruction) is diagnostic of renovascularhypertension.

Bilateral parenchymal retention is a nonspecific finding,however. Unilateral retention can be quantified as achange in the 20 minute/peak ratio of 0.15 or greater oras an increase inthe Tmax of at least 2 minutes or 40%between baseline and captopril studies.

an additional baseline examination without captopril.

The study is considered formally positive if the absolutevalue of the difference in renal function increases by 10%or more from the baseline to captopril study. Markedunilateral tracer retention after captopril is also consid-ered to indicate a positive study.

A difference in the absolute value of renal functionbetween baseline and captopril studies of between5% to 9% is considered an intermediate response, andthus not diagnostic.

Note that with normal renal function and withouthydronephrosis, the normal 20 minute/peak ratio is<0.3.Deviation from the normal value or a significantasymmetry in excretion warrants a comparisonbaseline exam.

DTPAA greater than 10% difference in renal function isconsidered provisionaly abnormal, and generally requires

Testicular Imaging

To aid in the differentiation of testicular torsion (in whichthere is decreased flow) from inflammatory processessuch as epididymitis (in which there is increased flowand ECF space tracer distribution).

Instruments and EquipmentLarge field of view gamma camera with low energy par-allel hole collimator and computer system.

For very small children a small field of view camera witha converging collimator may be necessary. The studyshould be discouraged in neonates since it is of little valuein this age group.

Radiopharmaceutical99mTc Pertechnetate.

Time of ImagingImmediately upon injection (requires flow study).

Dose555 MBq - Adult


This study should not be done in children younger thansix months.

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CLINICAL PRACTICES


AdministrationIntravenous injection of a small bolus using modifiedOldendorf technique and saline flush. Use 4-way stop-cock and appropriate butterfly needle and tubing.

Patient PositioningAnterior supine with testicles centered in the field of view.


Acquire static images in a 9 format for 1000kwith and without 57-Cobalt line source marker.

Static images should consist of three views:anterior, midline scrotal marker, and testicularmarker.

Digital:Acquire flow images at 2 second frame rate for32 frames (128 x 128 matrix).

Acquire static images with and without 57-Cobalt line source markerfor 1000K in a256 x 256 matrix.

Static images should consist of three views:anterior, midline scrotal marker, and testicularmarker.

Image AnalysisPrepare labeled save screens of the flow and staticimages and photograph. Submit all digital data andphotographs to the interpretation room for analysis.


CommentsIn setting up the patient for this procedure place thepatient in the supine position with hips slightly abducted.

A paper tape support (bridge) is placedacross both thighsand under the scrotum so that the testicles areparallel and equal distance from the collimator. The penisis taped (paper tape) to the anterior abdominal wall so asnot to overlie the testicles. The 57-Cobalt line source isstored in the radiopharmacy.

This procedure is done routinely for indications that arenot specifically listed in the manufacturer’s packageinserts. The choice of the radiopharmaceutical and thedose for each procedure described in this Manual is madeby the physician staff of the Nuclear MedicineDivision,in order to acquire the best imaging results while com-plying with MGH Isotope and/or Pharmacy Committeeguidelines. The name of the nuclear medicine physicianordering any test that is listed here is maintainedin the files of the radiopharmacy with the data on thepatient and radiopharmaceutical.

Radionuclide Cystogram

Radionuclide cystography has proven to be an effectiveand safetechnic for the detection of vesicoureteralreflux. If one wishes to examine the patient (particu-larly pediatric patients) during the filling, voiding and postvoiding phases of this test, the radionuclide VCUGprovides monitoring of the patient with a reducedradiation burden compared to conventional x-ray.

Instruments and EquipmentPreferred instrument, large field of view camera linkedto a computer; GAP or high resolution collimator.

Dose18.5 MBq (500 mCi) of 99mTc sulfur colloid.

Patient PreparationThe patient’s bladder is catheterized and urine sent forculture.

Attach an IV infusion set to the catheter via a 3-waystopcock, connected to a 500 ml bottle of saline.

The bottle should not be >100 cm above the table.

Cover gamma camera and table with absorbent paper.

TechniquePosition patient supine with the bladder in the lowerportion of the imaging field.

Inject 99mTc sulfur colloid via IV tubing andopen IVsaline to commence filling bladder.

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Image AcquisitionAnalog:

None

Digital:

Acquire image in a 128 x 128 matrix every 20seconds.

Commence imaging immediately and continueuntil voiding is complete.

Image AnalysisPrepare labeled save screen and photograph. Submit alldigital data and photographs to the interpretation roomfor analysis.

This procedure is done routinely for indications that arenot specifically listed in the manufacturer’s packageinserts. The choice of the radiopharmaceutical and thedose for each procedure described in this Manual is madeby the physician staff of the Nuclear Medicine Division,in order to acquire the best imaging results whilecomplying with MGH Isotope and/or Pharmacy Comitteeguidelines. The name of the nuclear medicine physicianordering any test that is listed here is maintained in thefiles of the radiopharmacy with the data on the patientand radio-pharmaceutical.

Hematology

Bone Marrow

This study is usually obtained to assess bone marrowdistribution in patients with anemia, or as an adjunct toIn-111 WBC imaging.

Instruments and EquipmentLarge field of view scanning gamma camera with low orenergy parallel hole collimator and computer system.

Radiopharmaceutical and Dose370 MBq- 99mTc sulfur colloid.

Time of Imaging15 min post injection.


AdministrationIntravenous administration.

Patient PositioningAnterior and posterior whole body. Selected spot viewsmay alternatively be needed per staff physiciandirection.


Acquire analog images in the whole body modeusing a scan speed of 15 centimeters per minute.

Digital:

Acquire whole body images in a 256 x 1024matrix (MS-2) or 384 x 1024 matrix using a scanspeed of 15 centimeters per minute.

Image AnalysisPrepare labeled save screen and photograph.Submit all digital data and photographs to theinterpretation room for analysis.

Special ViewsViews of the extremities are needed to determinethedistribution of bone marrow in long bones, if this isnot obvious on whole body images. Minimum 100K or 10minute images will be required (record which).

99mTc Labeled RBCVolume Determination

To determine the actual circulating red blood cell andalbumin volume to aid in the diagnosis of certain hemato-logic disorders in which the hematocrit may be elevated.

Radiopharmaceuticals125I radioiodinated human serum albumin: 125I-RISA.

99mTc autologous red blood cells 0.37-1.11 MBq:99mTc-RBC’s.

Dose125I-RISA0.37 MBq99mTc-RBC’s 0.37-1.11 MBq (100-300 mCi)

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CLINICAL PRACTICES


AdministrationInsert a 19 guage butterfly infusion set into a peripheralvein in each arm. Attach a stopcock and 10 ml of hep-arinized saline (10units/ml). Flush lines. Inject 0.37 MBqof 125I-RISA in right arm,flush syringe with blood andnote time. Note time.

Inject 3mls of stannous pyrophosphate containing1 mgstannous chloride in right arm and reheparinize the line.

Withdraw 5 ml blood samples from left arm at 15 and 30minutesfollowinginjection.

Withdraw and discard 3 mls blood before collectingactual samples. Reheparinize the line.

Twenty to thirty minutes following intravenous stannousion withdrawn 10 mls of blood into a syringe containing18-36 MBq 99mTc pertechnetate. Add 100 units ofheparin, mix and incubate for 10 minutes at roomtemperature. (See attached article on labeling method.)

In a vertical laminar flow hood, transfer the 99mTc-RBC’sto a sterile pyrogen free centrifuge tube (Corning50ml).

Add 10 mls of saline, mix gently, and centrifuge at100 x g (1200 rpm) for 5 minutes. Remove supernatantand discard.

Measure radioactivity on the RBC’s using a dosecalibrator. Calculatethe volume of 99mTc-RBC’s that isrequired.

Withdraw 1 ml of 99mTc-RBC’s into a 1 ml syringe andcap with luer cap (Paramedical no.57-01). Withdrawappropriate volume for patient dose and cap as above.Weigh each syringe accurately and record weights.

Measureand record 99mTc-RBC’s radioactivity. Injectthe 99mTc- RBC’s in the left arm. Do not flush syringe.Reweigh and record weight.

Withdraw blood samples as described above at 15 and30 minutes following injection.

Preparation of Standards

125I:Withdraw 0.2 ml 125I-RISA from same vial as

the patient dose. Expel 0.1 ml into a100 ml volumetricflask containing dilute albumin solution (to prevent lossof 125I- albumin on glassware). Mix and dilute to mark.Remove 2 x 1 ml samples for counting.

Dilution factor( 99m Tc DF) = Wt. of cells injected

Wt. of cells in STD ∩

100 ml

1 . 0 ml

99mTc:Expel contents of TB syringe containing 99mTc-

RBC’s into a 100 ml volumetric flask containing distilledwater and mix well.

Reweighand record syringe. Dilute to mark, mix andwithdraw 2 x 1 ml samples for counting.

Samples Preparation:125I-RISA:

Spin whole blood samples at 100 x g for 5minutes. Removeduplicate 1 ml aliquots of plasma and transfer tocounting tubes. Count forappropriate time to minimize statistical counting

error along with standard.

99mTc-RBC’s:Withdraw duplicate 1 ml whole blood samples.

Transfer tocounter tubes. Determine hematocrit of whole bloodsamples andrecord. Count for appropriate time to minimize

statisticalcounting along with standard.

Dilution factor( 99m Tc DF) = Wt. of cells injected

Wt. of cells in STD ∩

100 ml

1 . 0 ml

Interpretation

Plot log CPM/ml vs time.

Determine y intercept (manually or using computer fit).

Plasma Volume Net CPM (ISTD) x (IDF) = Plasma volume Net CPM/ml plasma at t=0

RBC Volume Net CPM/(Tc STD x (Tc DF) = RBC volume (Net CPM per ml whole blood at t=0) / (Hematocrit)

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Normal ValuesRBC Volume Plasma Volume

Males: 27-33 ml/kg 49-59 ml.kg

Females:23-27 ml/kg

Note: If the patient is more than 20% underweight oroverweight corrections for lean body mass should beperformed using standardnomograms.

Inflammation

67Ga Inflammation

Some infections and inflammatory processes are67Ga avid. There is slow blood clearance and excretionof gallium, so imagingnormally is not started until after48 hours. Labeled WBC’s are preferred for intra-abdominal infections.

Instruments and EquipmentLarge field of view gamma camera withmedium energyparallel hole collimator and computer. Set up the cam-era for gallium imaging using the following settings:

96 keV photopeak with a 30% window185 keV photopeak with a 30% window300 keV photopeak with a 30% window

Radiopharmaceutical67Ga citrate

Time of ImagingAll abdominal or whole body images should be performed72 hours after injection. Chest images may be imagedat 48 hours post injection.

Dose185 Mbq - Adult

Webster’s rule - Pediatric

Patient PreparationLaxatives 24 hours after injection and enemas thenightbefore imaging. This patient preparation is only to beused for whole body or abdominal imaging.

Patient PositioningWhen images are performed to ascertain an unknownfocus of infection or for fevers of undetermined origin,whole body images should be acquired in both theanterior and posterior projections.


Acquire spot images for 500K using a 4 format.Acquire whole body scan images using a scanspeed of 10 centimeters/minutes on scanningcameras.

Digital:

Acquire static spot images in a 256 x 256matrix for 500K Acquire whole body imagesin a 256 x 1024 or 384 x 1024 matrix.

Special ViewsAs requested by staff physician. In some cases, SPECTimaging may be required.

Image AnalysisPrepare labeled save screens of the images and uptakeresults and photograph. Submit digital data and photo-graphs to the interpretation room for analysis.

CommentsIf the patient already has 99mTc on board, only the 296keV photopeak with a 30% window can be used forgallium imaging.

Images may be performed earlier or later than 72 hoursat the discretion of the nuclear staff physician.

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CLINICAL PRACTICES

111In White Blood Cell Scanfor

Infection

This scan is performed to demonstrate specific foci ofinfection, by use of WBC’s from the patient, labeled with111In. This procedure is especially recommended forpatients with suspected abdominal and thoracicabscess(s).

Instruments and EquipmentLarge field of view gamma camera withmedium energyparallel hole collimator and computer system.

Radiopharmaceutical111In labeled white blood cells.


Dose7.4 MBq - Adult

Patient Preparation50 cc of the patient’s blood must be obtained forcell labeling.

AdministrationIntravenous administratrion of labeled white cells.


Projections:Whole Body Imaging - anterior and posteriorviews.

Spot Views - Anterior and posterior spotviews from the head to tibias.

Data Acquisition

Analog:

Acquire images on a whole body camera inwhole body format using a scan speed of 8centimeters/minute.

Acquire spot views in 9 format for 100K or 10minutes whichever comes first.

99mTc White Blood Cell Scanfor

Infection

This scan is performed to demonstrate specific foci ofinfection, by use of WBC’s from the patient, labeled with99mTc. This procedure is recommended for patients withsuspected abdominal and thoracic abscess(s) andosteomyelitis.

Instruments and EquipmentLarge field of view gamma camera withmedium energyparallel hole collimator and computer system.

Radiopharmaceutical99mTc-HMPAO labeled white blood cells.

Time of Imaging0.5-4 and possibly 18-24 hours post injection.

Early imaging is recommended for the evaluation ofinflammatory bowel disease.

Dose185-7.4 370 MBq - Adult

Digital:

Acquire images in the whole body format(256 x 1024 or 284 x 1024 matrix.

Acquire spot images in a 256 x 256 matrix forsame information density as listed above. Useauto contour with MS-2 cameras.



CommentsWhite Blood Cell labeling is performed by either Dr. RonaldJ. Callahan or Mr. Stephen Dragotakis.

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NUCLEAR MEDICINE

LungPatient Preparation50 cc of the patient’s blood must be obtained for celllabeling.

AdministrationIntravenous administratrion of labeled white cells.


Projections:Whole Body Imaging — anterior and posteriorviews.

Spot Views - Anterior and posterior spotviews from the head to tibias.

Data Acquisition

Analog:

Acquire images on a whole body camera inwhole body format using a scan speed of 12centimeters/minute.

Acquire spot views in 9 format for 150K or10 minutes whichever comes first.

Digital:

Acquire images in the whole body format(256 x 1024 or 284 x 1024 matrix.

Acquire spot images in a 156 x 256 matrix forsame information density as listed above. Useauto contour with MS-2 cameras.



CommentsWhite Blood Cell labeling is performed by either Dr.RonaldJ. Callahan or Mr. Stephen Dragotakis.

Lung Perfusion

To demonstrate (by capillary blockade) perfusion of thelungs, usually to diagnose pulmonary emboli. Regionaldistribution reflects the contribution of each area of lungto total lung function.

The particles used for the radiolabel are approximately3 times the size of a RBC, and temporarily block1/200,000 of the pulmonary capillaries in the normaladult.

Instruments and EquipmentLarge field of view gamma camera with all purposecollimator and computer system.


Radiopharmaceutical99mTc macroaggregated human albumin (MAA), roughly200,000-400,000 particles.

Reduce dose to 50,000-75,000 particles in adultsuspected of having pulmonary hypertension, and to5,000 particles in neonates.

DoseAge +1Age +7


AdministrationIntravenous injection with patient supine.

Patient PositioningAcquire perfusion images in the exact sequence asstated below:

LPO POST RPORAO ANT LAO

x 740 MBq (no less than 37 MBq)

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CLINICAL PRACTICES


Acquires all images for 1000K or 4 min./view. Insome cases, this can be reduced to750 K with the

Digital:

Acquire images in a 256 x 256 matrix on computer.In the case of a quantitative study, acquire imagesin the posterior and anterior projections.

Special ViewsAs ordered by the staff physician.

Image AnalysisPrepare labeled save screens of the images anduptakeresults and photograph.

Submit digital data and photographs to the interpreta-tion room for analysis.

CommentsHave patient take six (6) deep breaths before injection.

Havepatient take 5-10 deep breaths while injecting.

Image patient in the supine position.

Image AnalysisPrepare labeled save screens of the images and uptakeresults and photograph. Submit digital data andphoto-graphs to the interpretation room for analysis.

Regional Lung FunctionUse Automated Program for RegionalQuantitation.

In cases where the patient is immobile, the perfusionimages may be in thefollowing order:

POST LPO RPO

LAO ANT RAO

permission of a physician.

Lung Ventilation

To assess regional ventilation, especially in patientsunder evaluation for pulmonary embolism, and in patientsfor measurement of regional lung function. 133Xe is aninert gas which is minimally absorbed by the bodytissues.

Instruments and EquipmentLarge field of view gamma camera with lowenergy allpurpose collimator and computer system.

Radiopharmaceutical133Xe Gas

Time of ImagingImmediately upon inhalation of 133Xe.

DoseAge +1Age +7


AdministrationInhalation of Xenon gas.

Patient PositioningSupine, always in same position as the perfusion studywill be done.

Projections:

Posterior projection unless another projectionis specifically requested.

Data Acquisition

Analog:

Wash-in - 30K

Equilibrium - 2 images- 90 sec each, beginning after wash-in.

Washout - 3 images for 45 seconds each.

Retention - LPO, Posterior, and RPO imagesfor 45 seconds each.

x 740 MBq

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NUCLEAR MEDICINE

Image Format:

Initial Breath Equilibrum 1 Equilibrium 2Washout (45sec) Washout (45sec) Washout(45sec)

LPO (45) Posterior (45sec) RPO (45sec)

Digital:

Acquire in same manner as lung perfusionstudy.

CommentsTry to perform study in supine position.

Make sure patient has current chest x-ray, (done within12 hours) if pulmonary embolus evaluation.

If the perfusion study was performed prior to theventilation study,obtain a background image (99mTcscatter in the 133Xe window) for 120 seconds oncomputer to subtract from the washout images.

Computational Analysis

Regional Lung Function

For quantitative ventilation data, use automated program.

Calculation - Divide the counts from each region by totalcounts in the entire lung field to obtain % of uptake inthe specific region.

Pulmonary Aspiration

To determine whether there is evidence of gastroesoph-ageal reflux and pulmonary aspiration of gastric contents.Since this usually occurs during sleep, it is necessary tostudy the patientovernight.

Instruments and EquipmentLarge field of view gamma camera with low energy allpurpose parallel hole collimator and computer.


Time of ImagingDone as first case in morning.

Dose185 MBq


AdministrationThis study will be done on inpatients. On the eveningbefore imaging, the patient is given the radiopharmaceu-tical mixed with 15 ml Lipomula in a milkshake orMeritene.

Patient PositioningProjection: Anterior and posterior chest.

Data Acquisition

Analog or Digital:

Fifteen minute anterior and posterior images ofthe chest, along with marker image indicatinglocations of the sternal notch and xiphoid.


Endocrine

Thyroid Imaging and Uptake

(99mTc)

For function and structural assessment of the thyroidgland, using 99mTc Pertechnetate which is incorporatedin the thyroid gland but not organified.

Instrument and EquipmentRegular field of view camera with a pinhole collimatorand 5 mm insert and computer.

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CLINICAL PRACTICES

Radiopharmaceutical99mTc Pertechnetate (permits rapid uptakeand imag-ing compared to I123 where imaging is usually performedat 24 hours).

Dose370 MBq - Adult



Time of Imaging20 minutes post injection.

Uptake:

Count standard in phantom at a distance of 20 cm withpinhole insert in place for 2 minutes. The 20 minute99mTc patient uptake is then determined by repeat count-ing of the patient’s neck using the same countinggeometry.

Standard ProjectionsAnterior 6 cm from surface of neck.

Anterior 57Co supersternal notch marker in conjunctionwith 5 cm 57Co measure marker parallel to thyroid lobes.

If necessary right anterior oblique, and left anterioroblique at a distance that will fill 2/3 of pinhole field ofview.

Information Density250K per image

75K per image for 57Co marker images

Special ViewsIt may be necessary to mark areas where nodules arepresent, using 99mTc wand.

CommentsSee Computer section for calculation of % uptake.

Have 99mTc marking sources available.

Have a glass of water available to be used in palpation ofthyroid gland.

Acquire all computer images in quadrant format(128x128).

Make duplicate copies of all hard copy images. Fill outand submit uptake calculation sheet along with hard copyimages for interpretation.

Thyroid Uptake and Imaging

(123I)

For function and structural assessment of the thyroidgland, using 123I which is naturally incorporated in thethyroid gland.

Instruments and EquipmentGE camera and computer

Pinhole collimator with 5 mm insert57Co wand for marking

Thyroid logbook

Thyroid floppy disk

Thyroid magnetic tape

Sharpie for marking patient

Radiopharmaceutical123I sodium iodide

Dose8 MBq 123I (1-2 capsules) 24 hours prior toscanning.


Time of Imaging24 hours

Computer AcquisitionThyroid capsules are counted in a neck phantom at adistance of 20 cm without the pinhole insert for 5 min-utes. Uptake determination in the patient is performedfor the same time and counting geometry.

All images are acquired in 128x128 (quadrant format).They arestored on a thyroid floppy disk and transferredto a thyroid magnetic tape in byte mode (256) for longterm storage.

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CommentsPatient is palpated by Thyroid Fellow and NuclearMedicine Resident.

If it is a question of nodule, the area will be marked forscanning.

Patient is placed in supine position with neck extended.

Marks are placed on suprasternal notch and for4 cm markers at level ofthyroid gland.

Standard ImagesAnterior, 6 cm from collimator - 8 minutes.

If the thyroid is enlarged, it may be necessary to imageat 10 cm to include the entire thyroid in the field of view.

Without moving the patient, multiple 2 sec acquisitionsare done in quadrant two with the 57Co wand placedover the marks (SSN; 4 cm markers; nodule if marked)(eg. SAQ, S, QZ; SAQ S, Q2; SAQ S Q2).

If there is a question of nodule or if deemed necessaryby the physician, both an RAO and an LAO should beperformed. These are done in a 45o angle at 6 cm for 5minutes centering the nodule in thefield of view.

Post Scan Analysis

Transfer images on disk to magnetic tape for long termstorage.Use byte mode (256) on designated thyroid tape.Record all pertinent information in thyroid logbook.Photograph images on hard copy using the multiformatter.Two copies are needed: one for Thyroid Lab and one forNuclearMedicine.

The images recorded are as follows:Make up Nuclear Medicine folder and give all paperwork and hard copy to Nuclear Medicine Resident.Leave three polaroid images at thyroid clinic.

123I Potassium PerchlorateWashout Test

Instruments and EquipmentRegular field of view gammma camera.

CollimatorPinhole with 5 mm insert.

Radiopharmaceutical123I Sodium Iodide

Dose8-20 MBq - Adult

Webster’s Rule - (Pediatric)

Starting Time45 minutes post 123I administration (capsule dose).

40 minutes after the tracer dose of 123I image thethyroid phantom.

At 45 and 60 minutes post dose the patient will beimaged.

Potassium PerchlorateAdult dose: 400 mg (2 capsules).

Pediatric dose: Webster’s Rule or check with staffphysician.

After initial images have been obtained, dosethe patient with 400 mg of PotassiumPerchlorate.

40 minutes after the dose of PotassiumPerchlorate the thyroid phantom is again imaged.

At 45 and 60 minutes after the dose ofPotassium Perchlorate the patient is imaged.

Standard ProjectionsAnterior at 6 cm from surface of the neck.

Imaging TimeImaging time for all views (both patient and phantom)will be for 5 minutes.

Special ViewsTo be determined by Staff Nuclear Medicine physician.

CommentsAll images (patient) will have uptake values computedusing the “thyroid” program on the computer.

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CLINICAL PRACTICES

Parathyroid Imaging

99mTc-sestamibi accumulates in normal and abnormalthyroid, as well as in enlarged parathryoid glands.Sestamibi rapidly washes out from normal thyroid tis-sue; thus, delayed images should show only abnormaluptake.

Instruments and EquipmentLarge field of view camera with all purposeor high reso-lution parallel hole collimator and interfacedcomputer.In some cases, imaging with a 5 mm pinholecollimatormay be required.

Radiopharmaceutical740 MBq 99mTc-sestamibi

Time of ImagingInitial images immediately after injection.

Delayed images approximately two hours after injection.

Image AcquisitionAcquire immediate anterior planar image of the neck andupper chest, so that the most superior aspect of the heartis at the bottom of the field of view.

This should be recorded for 5 minutes in 128 x 128matrix size.

Perform SPECT acquisition of neck and upper chestusing 360o rotation, 96 views per head, 15 seconds perview.

Record 5 minute pinhole image of neck in the anteriorprojection, with the pinhole aperture approximately10 cm from the neck.

Repeat each of these images at the time of delayedimaging.

Image AnalysisPrepare labeled save screen of planar and pinholeimages.

Reconstruct and photograph SPECT images in thetransaxial, coronal, and saggital planes.

CommentsIn selected cases, additional oblique images of the neckmay be needed. If a mediastinal abnormality is shown,delayed images may not be needed.

Iodine-131 MIBG Imagingof

Adrenergic Tumors

Labeled MIBG (meta-iodobenzylguanidine) is a precursorfor several types of adrenergic tumors, most notablypheochromocytomas.

In adults, about 90% or pheochromocytomas lie withinthe adrenal medulla. In children, up to 30% may beextra-adrenal.

Radionuclide evaluation is usually warranted only whenCT evaluation has not demonstrated the suspectedtumor. Other adrenergic tumors that may be shown byMIBG imaging include paraganglioma, neuroblastoma, andcarcinoid. Some investigators believe that these lattertumors may be better shown with octreotide imaging.

Instruments and EquipmentLarge field of view gamma camera with parallel hole highenergy (400 or 511 keV) collimator.

Radiopharmaceutical18 MBq 131I MIBG

Time of imaging24 and 48 hours post injection.

On selected occasions, 72 hour images may be needed.

Patient PreparationThe patient must be screened for medications that mayinterfere with MIBG uptake. These include sympathomi-metics, calcium channel blockers, reserpine, cocaine,tricyclic antidepressants, adrenergic blockers, and someover-the-counter cold medications(e.g., containingpseudoephedrine).

Thyroid iodine uptake must be blocked by administeringSSKI beginning 2 days before tracer administration, andcontinuing for 5 days thereafter. The usual dose is 6drops per day.

Tumor

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NUCLEAR MEDICINE

Image AcquisitionAnterior and posterior spot views of the neck, chest,abdomen, and pelvis should be acquired for 15 minuteseach, using a 128 x 128 matrix size.

Images must include the body from the base of the skullto the inferior bladder.

Image Analysis Prepare labeled save screen of images.

CommentsIt may be necessary to inject a second radio-pharmaceu-tical such as 99mTc-DTPA or pertechnetate to provideanatomic orientation for any abnormal findings.

ReferenceMcEwan AJ, Shapiro D, Sisson JC et al. Radio-iodobenzylguanidine for the Scintigraphic Location andTherapy of Adrenergic Tumors. J Nucl Med 1985;15:132-153.

67Ga Tumor

Certain primary and secondary tumor deposits are67Ga avid. This radiolabel is used most commonlyin patients withlymphoma.

Instruments and EquipmentLarge field of view gamma camera with medium energyparallel hole collimator andcomputer.

Set up the camera for gallium imaging using the follow-ing settings:




Radiopharmaceutical67Ga citrate


Earlier images of the chest may be performed at the staffphysician’s discretion.

Dose300 MBq - Adult


Patient PreparationLaxatives started 24 hours after injection and enemasthe night before imaging. This patient preparation is tobe used only for abdominal or whole body imaging.

AdministrationIntravenous injection of the radio-pharmaceutical.

Patient PositioningProjections:

Total Body Spot Views.

Anterior and posterior head with neckincluded.

Anterior and posterior chest with axillaryarea included.

Anterior and posterior abdomen.

Anterior and posterior pelvis and upper legs.

Total Body Scan:Under special circumstances (determined bythe staff physician), imaging may be performedin a body scan mode using a scan speed of10cm/min.

Data Acquisition

Analog:

Acquire spot images for 10 minutes using a 9 onone format.

Digital:

Acquire static spot images in a 256 x 256 matrix.

Total Body Imaging:

Scan speed of 10 cm/min for analog and digitalimages.

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CLINICAL PRACTICES



CommentsIf the patient already has 99mTc on board, only the300 keV photopeak with a 30% window can be used forgallium imaging.

Images may be performed later than 72 hours at thediscretion of the nuclear medicine staff physician.

Note: This procedure is done routinely using dosesthat are greater than those listed in the manufacturer’spackage inserts. The choice of the radiopharmaceuticaland the dose for each procedure described in this Manualis made by the physician staff of the NuclearMedicine Division, in order to acquire the best resultswhile complying with MGH Isotope and/or PharmacyCommittee guidelines. The name of the NuclearMedicine physician ordering any test that is listed hereis maintained in the files of the radio-pharmacy with thedata on the patient and radio-pharmaceutical.

131I Whole Body or Neck withQuantitation

Instruments and Equipment

The preferred instrument is a large field of view gammacamera equipped with ultra-high energy collimators andcomputer system.

Peak camera for dual window acquisition with 20%windows set at 364 Kev (131I ) and 140 Kev (99 mTc).

Radiopharmaceutical131I Sodium Iodide

Dose131I administered by Thyroid Lab.

Inject patient with 40 MBq 99 mTc Pertechnetate IV.


Time of Imaging24 -168 hours post oral administration.

Patient PositioningAnterior and posterior dual window images of:

Head, neck and upper chestChest and upper abdomenAbdomen and pelvisLower extremities

Data Acquisition

Analog:Not required

Digital:Fifteen minute anterior and posterior dual win-dow images of:

Head, neck and upper chest

Chest and upper abdomen

Abdomen and pelvis

Lower extremities.

Use 256 x 256 matrix.

Acquire 131I standard phantom images for60 seconds, anterior and posterior.

Image AnalysisFormat images with the 131I display MPE on the ICONcomputer.

If there are focal areas of increased 131I accumulation,calculate uptake with the 131I uptake MPE on the ICONcomputer.

Preparelabeled save screens of the images and uptakeresults and photograph.

Submit digital data and photographs to the interpreta-tion room for analysis.

ReferenceCastronovo FP, et al; Dosimetric Considerations WhileAttending Hospitalized I-131 Therapy Patients. J NucMed, September 1982,Vol 10, No.3.

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NUCLEAR MEDICINE

Miscellaneous

Strontium - 89Radiotherapy

89Sr chloride is indicated for the palliation of bone painin patients with painful skeletal metastases. It is usedin patients unresponsive to chemotherapy or hormonaltherapy.

Most patients considered for 89Sr treatment havealready undergone external beam radiation therapy. Thebest results have been in patients with metastatic breastor prostate cancer, although other tumor types may betreated.

There may be a transient increase in bone pain at36-72 hours following treatment. The relief of painfollowing 89Sr therapy typically occurs in 7-20 days.Repeat treatment doses may be given in three months insome selected patients who responded to the initialtreatment.

89Sr has a half-life of 50.5 days, and decays by a1.4 MeV emission, without significant gamma emissions.In consequence, 89Sr cannot be imaged. 89Sr behavesbiologically as a calcium analog, with rapid blood clear-ance and uptake in bone.

In patients with extensive metastatic disease, more thanone half of the injected dose may localize in bone. Abouttwo-thirds of excretion is urinary, and one-third fecal.There is significant urinary excretion during the first 48hours after tracer injection.

IndicationsThe patient must meet the following entrance criteriafor 89Sr therapy:

Documented bone metastases unresponsive totherapy.

Life expectancy of at least two months.

Previous bone scan showing metastatic lesions,preferably within several months prior totreatment.

Evidence that bone marrow is not severely com-promised, as indicated by current (within 1week) WBC count of > 3000 and platelet countof>60,000.

Must not be incontinent of urine or feces.

Must be able to give informed consent.

This procedure will not be done on inpatientsbecause of the logistics of radiation safetyissues.

In rare instances, a medical decision may be made toproceed with treatment, despite noncompliance with oneor more of the criteria above.

Scheduling of ProcedureRequests for 89Sr treatment from an attendingphysician will be handled directly by a Nuclear Medicinestaff physician. The Nuclear Medicine physician willcomplete an information form that indicates the patient’sname, unit number, age, weight, and diagnosis.

Hematologic data should be faxed by the referringphysician’s office or obtained from PCIS prior toscheduling.

The staff nuclear physician will forward this informationto the Nuclear Medicine division secretary designated tohandle 89Sr therapy records for scheduling. A NuclearMedicine “Special Studies” form will be completed andforwarded to the nuclear pharmacy so that the radiop-harmaceutical dose can be ordered. A 89Sr treatmentfolder will be made and kept in the Nuclear Medicinestaff office files that contains all of this relevant data,along with reports of any relevant imaging studies.

At the time of scheduling, a confirmation form will befaxed to the referring physician’s office. This formreviews the protocol for follow-up hematology studiesthat will be obtained by the referring physician.

ConsentAt the time of treatment, the Nuclear Medicine staffphysician administering the therapy will discuss theprocedure with the patient and obtain written consentusing the 89Sr Therapy consent form.


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CLINICAL PRACTICES

Written DirectiveThe Nuclear Medicine staff physician will complete thewritten directive form, including the following data:

date, patient name,patient weight, patient date of birth,referring physician name,Nuclear Medicine physician name,two methods of patient identity verification,date and findings of the most recent bone scan,the patient’s hematocrit,WBC and platelet counts,and the administered dose requested.

Dose1.5-2.2 MBq/kg up to a maximum of 150 MBq. Anydosage in this range reflects acceptable adequatedosage; the exact dosage within this range may beselected based upon the amount of radiopharmaceuticalavailable.

TechniqueInsert a secure route of intravenous access, suchas a 20 gauge angiocath with a three way stop-cock.

Infuse enough normal saline to confirm theadequacy of intravenous access.

The 89Sr dose will be given by the Nuclear Medi-cine staff physician as a slow injection over aboutone minute.

Following administration, flush both the injectionsyringe and stopcock with at least 10 ml ofsaline.

Remove the IV setup and wrap the syringe andtubing in the impervious drapes used for theinjection.

This will be marked “Sr-89” and placed instorage for transfer to Radiation Safety. In caseof a spill, contain the contamination and call theRadiation Safety office at 6-2425.

The room used for administration will be moni-tored for contamination following each injection.

Miscellaneous

Follow-UpIt is recommended that the patient’s peripheralblood counts be checked at least every otherweek following 89Sr administration to evaluatefor marrow depression.

The CBC should be checked more often ifvalues fall below treatment thresholds.

Platelet levels typically reach a nadir of about70% of the pre-existing value at 3-4 monthsfollowing treatment.

The depression of WBC counts is more variable,but blood counts may not return to pre-treat-ment levels for about 6 months.

Approximately 2 weeks after treatment, follow-up blood counts will be verified by contactingthe referring physican’s office or from PCIS.

RecordsThe Nuclear Medicine staff physician will dictate areport of the therapy administration, including theclinical history, laboratory values, and dosageadministered.

A copy of this report will be retained in the patient folderkept in the Nuclear Medicine staff offices. A copy of thewritten directive will be maintained in the nuclearpharmacy computer system, as well as in the patientfolder.

Radiation Safety Considerations and

Precautions89Sr is excreted via the urine for a prolonged period, butmost activity is within the first week (and most of thatin the initial 48 hours). The patient should be instructedto double flush toilets during this time. Fecal mattercontains appreciable activity for about 4 days. Bloodactivity is significant for about 24 hours, and bloodsamples should not be drawn during this time except inan emergency situation.

If the patient returns to the hospital for treatment withinthe first week after therapy, urine specimens, dressings,linens, and gloves should be considered radioactive, andcollected by the Radiation Safety Office. Surgical ormedical procedures may be performed with carefulattention to Universal Precautions. An autopsy orcremation should not be performed unless authorized bythe RSO.

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NUCLEAR MEDICINE

Miscellaneous

111In Pentetreotide Imaging

A variety of neuroendocrine tumors (insulinoma,gastrinoma, VIPoma, neuroblastoma, etc.) express highconcentrations ofsomatostatin receptors.

In many cases, these patients have been effectivelytreated with the somatostatin analog - Octreotide. Insome situations, tumor localization can be achieved with111In labeled - Octreotide (OctreoScan).

Instruments and EquipmentLarge field of view gamma camera with a medium energyparallel hole collimator and computer system.

Twenty % windows should be set to include the172 and 245 keV photons of 111In.

Radiopharmaceutical111In labeled OctreoScan

Time of Imaging4 and 24 hours after.

In some cases, only 24 hour imaging will be necessary(see staff physician).

In some cases, 48 or 72 hour imaging may be required todifferentiate tumor uptake from normal bowel activity(see staff physician).

DoseAdults: 185 MBq of 111In labeled OctreoScan (planar+ SPECT).

Children:Webster’s rule (never use <37 MBq).

Patient Preparation

Bowel Prep: Mild laxative (e.g. bisacodyl orlactulose) after injection.

Hydration: Patient should be well hydrated (atleast 2 glasses of water) to enhancerenal excretion.

Concurrent Octreotide Therapy:Discontinue 24-48 hours prior to imaging (ifpossible) and monitor patient for signs ofwithdrawal.

AdministrationIntravenous injection of the radiopharmaceutical.

Patient PositioningPlace the patient in the supine position and acquirethe following views.

Planar Imaging:

Ant. & Post: head, neck and upper chestAnt. & Post: chest and upper abdomenAnt. & Post.: abdomen and pelvisAnt. & Post.: lower extremities

SPECT: Area of interest.


Acquire spot images in 9 format for 500K or 10minutes, whichever comes first.

Digital (planar):Acquire images in a 256 x 256 matrix for the sameinformation density as indicated above.


In most cases, SPECT will be required.

SPECT (MS-2)Acquire 96 projections over 360o on each head: 20 sec./projection in a 128 x 128 matrix.

Reconstruct the data usinga Butterworth filter(cutoff = 0.4, order = 7).

Do not use attenuation correction.

Image ProcessingPrepare labeled save screens of all planar (generaldisplay) and SPECT data (multi-view display) andphotograph. Submit all analog and digital data andphotographs to the interpretation room for analysis.

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CLINICAL PRACTICES

Miscellaneous

Normally, there is minimal right to left shunting and mostof an injected dose of radiolabeled albumin micropheresshould be trapped in the lungs.

The percentage found outside the lung relates to theextent of R-L shunting.

Instruments and EquipmentRegular or large field of view gamma camera equippedwith a general all purpose collimator and interfaced to acomputer.

RadiopharmaceuticalMacroaggregated albumin (less than 100,000 particleslabeled with 99mTc.

The number of particles is reduced for infants andchildren.

Dose150 MBq - adult

Webster’s rule - pediatric

Time of ImagingImmediately after injection.



Patient PositionSupine

Right to Left Shunt (MAATechnique)

Data Acquisition

Qualitative Technique

Acquire anterior image of brain, palmar imageof hand, or other projections as indicated bystaff physician.

Use a 256 x 256 matrix and acquire eachimage for 5 minutes.

Quantitative Technique

Acquire whole body anterior and posteriordigital image using either the Siemens bodycamera or MS-2 at 5 cm/min.

Draw regions of interest over the whole bodyand the lungs.

Determine the number of counts in each regionand calculate geometric means.

Calculate the degree of shunting using therelation:Amount of R-L Shunt = 1 - [Lung/Whole Body]

NOTE: This procedure is routinely performed usingdoses that are greater than those listed in themanufacturer’s package inserts. The choice of theradiopharmaceutical and the dose for each proceduredescribed in this Manual is made by the physician staffof the Nuclear Medicine Division, in order to acquire thebest results while complying with MGH Isotopeand/or Pharmacy Committee guidelines. The name of theNuclearMedicine physician ordering any testthat is listed here is maintained in the files of theradiopharmacy with the data on the patient dose ofradiopharmaceutical.

ReferenceEditorial: Am Rev Resp Disease 1977;115:553-557

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NUCLEAR MEDICINE

Miscellaneous

Lymphoscintigraphy: Melanoma

En bloc lymph node resection is done in high riskmelanoma patients in a attempt to reduce recurrentdisease.

When the primary lesion is on the trunk, lymphatic drain-age may be to either axillary and/or inguinal region, aswell as to other nodal groups such as supraclavicularand para-aortic nodes.

Lymphoscintigraphy is employed to identify the nodalgroup or groups at highest risk, and to localize thesentinel node(s).

Instruments and EquipmentLarge field of view camera equipped with high resolutionor all purpose collimator and computer.

RadiopharmaceuticalFiltered 99mTc sulfur colloid.

Dose5-10 MBq in 4 insulin syringes as follows:

1.25 - 2.5 MBq per syringe in 0.2 ml volume per syringe.

SuppliesSterile prep kit, non-sterile gloves, Betadine, 57Co“thyroid” marker.

AdministrationUsing insulin syringes, four to six intradermal injectionsare made around the biopsy site.


Not required

Digital: Up to three sequential 5 minute images in a128 x 128 matrix.

The initial images must include the site ofinjection.

The subsequent images should include detecteddrainage pathways.

If the lesion is truncal, both axillary and inquinalregions should be evaluated.

At 2 hours after injection, additional 5 minuteposterior and anterior images may be acquired.

Identify the tips of the shoulders and iliac crestswith the 57Co marker. A physician will localizethe sentinel node(s), and make any skin marksas needed.

Image AnalysisPrepare labeled save screens of all images and photo-graph. Submit all digital data and photographs to theinterpretation room for analysis.

InterpretationAs requested by the referring physician, the path(s) andnodal group(s) which drain the injection site may be iden-tified, and the location of the sentinel node(s) noted andmarked on the patient.

ReferenceJournal Nuc Med 1993;34:1435-1440

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CLINICAL PRACTICES

Miscellaneous

Schilling TestPart I

Orally administered vitamin B12 is either absorbed fromthe intestine or excreted in the feces. If, however,two hours after an oral dose of the vitamin B12,a patient receives an intramuscular injection of thevitamin, he will excrete <30% of the oral dose inhis urine. By employing this “flushing” technique withan oral dose of radioactive labeled vitamin B12, urinaryexcretion of the vitamin and consequently bodily absorp-tion can be easily monitored. Less than 7% excretionindicates malabsorption.

Instruments and EquipmentRubratope - 57 (~0.5 mCi/capsule) SquibbCopatope - 57 (~0.01 mCi/ml) SquibbCyanocobalamin Injection, USP (1,000 mcg/ml), Wyeth24-hour Specimen Collection Containers, SageGamma Counter, Micromedic 2/200

Specimen24 hour urine

Patient PreparationDiscuss the protocol with the patient.

The patient MUST be NPO — except for water for atleast 8 hours prior to testing and SHOULD NOT receivean injection of vitamin B12 within 24 hours of the test.

Most convenient is a fast from midnight with the testbeginning after 8 a.m.

Schedule test Monday thru Thursday. Friday schedulingrequires storage of the urine collection over the week-end and is discouraged.

Administration

Confirm patient preparation.

PERSONALLY give to the patient and watch himswallow a Rubratope - 57 capsule.

InpatientsLeave with the patient a 24 hour specimencollection container labeled with his name,floor and unit number as well as the start andcompletion date and time.

Inform the patient and remind the attending nurseor unit coordinator of the remaining testprocedures.

The patient may eat a light breakfast of juice,coffee and toast one hour after taking theRubratope - 57 capsule.

OutpatientsGive the patient a 24 hour specimen collectioncontainer labeled as described under “Inpatients”and a copy of the “Schilling Test Instructions”completed as indicated. (See below.) Explain thecollection and instructions as necessary.

Inform the patient that on his return to the labo-ratory 2 hours later he will receive an intramus-cular injection of vitamin B12 (cyanocobalamin- 1,000 mcg). It is the responsibility of the tech-nologist to find an appropriate person toadminister the B12 shot. If no one can be foundin a reasonable period of time, then send thepatient to Medical Walk-In Unit with an inter-clinicreferral slip signed by Dr. Fischman.

The Medical Walk-In Unit will provide andadminister the B12 shot.

Acquiring breakfast and returning of the 24-hoururine sample are the responsibilities of the patient.

AssayRecord volume of 24 hour urine collection.

Aliquot three, 2 ml samples of the collection into gammacounting tubes.

Also aliquot a 2 ml sample of the patient’s backgroundurine* and a 2 ml sample of Cobatope - 57 diluted1 ml to 2 mls with distilled water.

**This aliquot represents 2% of the radioactivity con-tained in Rubratope-57 capsule of the same lot number.

Count all tubes (10) as follows:

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Input (A=Assay;;S=Stat;T=Tape): AASSAY No.: 1COMMENT: returnCOUNTING TIME (MIN.): 10ISOTOPE (I=IODINE; C=COBALT) : CNO. TUBES: 10TUBE SIZE (S=8 X 50; L=12 X 75): SBACKGROUND COUNTS (CPM):

A: returnB: return

001, 10, 019227 - DILUTED CO-57002, 10, 000131 - BACKGROUND003, 10, 000671 - SAMPLE #1004, 10, 000657 - SAMPLE #1CRYSTAL B005, 10, 000674 - SAMPLE #1

006, 10, 019147 - DILUTED CO57007, 10, 000136 - BACKGROUND008, 10, 000836 - SAMPLE #2009, 10, 000851 - SAMPLE #2CRYSTAL A010, 10, 000847 - SAMPLE #2

EXAMPLE OF 2 PATIENTS(10 TUBES)

Calculations

% Excretion = Average CPM ( Sample) − CPM ( Backgr

CPM ( Diluted Rubratope − 57) − C

NORMAL RANGE:>10% excretion (borderline 7-9%)

If Excretion is NormalPour remaining urine down the radioactivewaste sink, flush with water and recordmicrocuries disposed of on radioactivewaste log.

Report results.

If Excretion is AbnormalSend an aliquot of urine to the Chemistry Labfor a creatinine level.

Discard remaining urine and record microcuriesdisposed of on radioactive waste log.

Report results.

Include creatinine results as ng/ml.

Comment on completion of collection asnecessary.

Common Interferences

• Laxatives, enemas or barium studies administered during the test.

• Gamma emitting isotopes administered before or during the test e.g.

ISOTOPE SCAN T1/2 - physical

Iodine - 131,123 Thyroid 8 days, 13 hoursTechnetium-99m Brain 6 hoursTechnetium-99m Bone 6 hoursTechnetium-99m Renal 6 hoursTechnetium-99m Lung 6 hoursGallium - 67 Whole body 3 days

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Schilling TestPart II

If Part I of the Schilling test documents malabsorption ofvitamin B12, Part II is performed to test for intrinsicfactor deficiency as the cause of malabsorption.

A dose of commercial intrinsic factor is given along withthe radioactive Vitamin B12.

Normal percent excretion indicates intrinsic factordeficiency.

Abnormal excretion eliminates intrinsic factor deficiencyas the cause of malabsorption but is otherwiseindiscriminate.

Instruments and EquipmentIntrinsic Factor Concentrate (1 N.F. x 1 unit/capsule),Squibb.

See Part I.

Specimen24 hour urine

Patient PreparationExcept for the following changes, proceed as outlinedin Part I.

PERSONALLY give to the patient and watch himswallow a Rubratope-57 capsule along with an intrinsicfactor capsule.

NORMAL RANGE: Same as Part I

ReferencesSchilling RF. Intrinsic factor studies II. The Effect ofGastric Juice on the Urinary Excretion of RadioactivityAfter the Oral Administration of Radioactivity B12. JLab and Clin Med;1953:42:860.

Med 1955;45:926.

ALLOW AT LEAST 3 DAYSBETWEEN PART I AND PART II

Schilling RF, Clatanoff DV, and Korst DR. Intrinsicfactor studies III. Further Observations Utilizing theUrinary Radioactivity Test in Subjects withAchlorhydia, Pernicious Anemia or Total Gastrectomy. JLab and Clin

SCHILLING TEST INSTRUCTIONS

X = STARTING TIME/INGESTION OF 57Co CAPSULE

AFTER SWALLOWING THE VITAMIN B12 CAPSULE:

You may eat a light breakfast (coffee, tea, juice, toast)AT X + 1 HOUR AM

You must return to the lab at X + 2 HOURS AM

STARTING NOW,

Save all of your urine for the next 24 hours in thecontainer provided.

Return the collected urine at your convenience tomor-row between 8:00 a.m. and 5:00 p.m.

SHOULD ANY OF YOUR URINE FOR THE NEXT 24HOURS BE DISCARDED BY MISTAKE, PLEASE NOTE THETIME AND THE APPROXIMATE AMOUNT LOST.

PLEASE HANDLE THE COLLECTED URINE WITH CARE.

THE MATERIAL CONTAINED WITHIN THE CAPSULE YOUHAVE SWALLOWED IS SLIGHTLY RADIOACTIVE. PARTOF THIS MATERIAL IS EXCRETED IN YOUR URINE.

ANY SPILLAGE SHOULD BE THOROUGHLY WIPED-UPOR WASHED OFF OF THE AREA INVOLVED.

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DISTRIBUTION OF SCHILLING TEST RESULTS 1981-1984

N = 417

0

1.252.5

3.75

5

6.257.5

8.75

10

11.25

12.5

13.75

15

16.25

17.5

18.75

0

10

20

30

40

50

60

% EXCRETION

CONCLUSION: Distribution suggests the addition of a borderline range.

Normal Range: >10% Excretion

Borderline: 7 - 9% Excretion

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Procedure for Counting Samplesfor

The Schilling TestUsing Micromedics 2/200 Scintillation Counter

The Micromedics scintillation counter is a dual sodiumiodide detector system designed primarily forradioimmuno assay work and other limited in vitro nuclearmedicine studies using very low levels of 125I or 57Co.

It is not suitable for general gamma scintillation count-ing due to lack of sufficient shielding between detectorsand non-linearity at higher counting rates.

It is not suitable for 99mTc red blood cell volume studiesas we now perform them.

General InformationThe system should be left on at all times. Test tubeholders must be loaded onto the left hand side of thecounter surface with position number 1 at the right sideof the rack.

Only 12 mm x 74 mm plastic tubes should be used. Capswhich protrude above the line positioned at the top ofthe tubes cannot be used. Cork stoppers which can bepushed into the tube below this mark should be used.

Uncapped samples should not be counted in this systemdue to the possibility of spillage and contamination.The system has no storage or data handling capabilities.All data must be entered at the beginning of each assay.Background count rates must be determined for eachdetector and values entered at the beginning of eachassay. The entered value will then be subtracted fromallcounts.

Counting times can be set from 0.1 to 25 minutes. Out-put from the system includes assay number, tubenumber, counting time and background corrected countsper minute with a maximum of six digits.

All input and output to the system is through the key-board/printer. The cap-lock must be depressed atall times.

Background Level Determination

Place ten uncapped tubes in a rack and place on left sideof counter surface. Place rack as far forward as pos-sible.

Release retaining arm and allow it to go forward untilcontact with tube rack is made. Clear all test tube racksfrom right side of counter surface.

Press “teletype input” button located on control panelUsing the printer keyboard, respond as indicated belowSome entries must be followed by a return others do not.

Printer Output Operator Response

Input (A-Assay;S=Stat;T=Tape): AAssay No.: (enter any #)Comment: BG, DateCounting Time (min): 1Isotope (I=Iodine; C=Cobalt) CNo. Tubes: 10Tube Size: LBackground Counts (CPM):A: 0B: 0

Press “Start” Button on Control Panel - Assay willproceed automatically.

To calculate background levels to be entered in assaysperformed during the day determine the average cpm fromthe output data as follows:

Average of positions 1 to 5 is the background level fordetector “B.”

Average positions 6 to 10 is the background level for de-tector “A.”

Record these values in the daily log book.

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Daily Constancy Using 129I Sealed Sources

Obtain 129I sources labeled “A” and “B.”Place source “A” in position number 6.Place source “B” in position number 1.Leave other positions empty.

Proceed as above for background determination exceptenter the following:

Comment: 129I, DateIsotope (I=Iodine;C=Cobalt) INo. Tubes: 6Background Counts (CPM):

A: (enter #’s from above)B: (enter #’s from above)

Output Data:

Value from position #1 is the 129I counts for detector B.Value from position #6 is the 129I counts for detector A.

Record these values in the daily log book.

Counting of Schilling Samples

Load samples as usual.

Proceed as above.

Enter the following:

Input (A=Assay;S=Stat;T=Tape): AAssay No.: (enter any #)Comment: Pt Names, etc, DateCounting Time (min): 25Isotope (I=Iodine;C=Cobalt) CNo. Tubes: (enter # of tubes)Tube size: LBackground Counts (CPM):A: (enter BG from above)B: (enter BG from above)

Oldendorf Techniquefor

Bolus Infection

The subject’s arm is positioned slightly elevated. A bloodpressure cuff is placed on the upper arm and inflated toabout 100 mm of mercury, provided that this is belowthe systolic brachial arterial pressure.

The cuff is left in place for about three minutes, causinga distention of the venous pool in the distal arm and arise in the venous blood pressure in the distal arm toexceed the cuff pressure.

Then the cuff pressure is further increased until it sub-stantially exceeds the systolic pressure (200-300 mmHg).The circulation in the distal arm is thus cut off with thevenous pool still in the distended condition.

With the arm circulation thus interrupted, the radiophar-maceutical is injected into the antecubital vein. The rateof injection need not be rapid, since the circulation iscompletely interrupted by the inflated cuff.

A small needle is preferred.

After the injection has been completed, the cuff isremoved abruptly while fully inflated.

The needle is removed later.

No pressure is applied to the injection site since this mightimpair venous drainage.

The collapsing venous pool accelerates delivery of thebolus of injected radionuclide to the right heart.

After the isotope is in the vein, removal of the cuff canbe delayed for periods of as long as one minute to permita final check of the instrumentation since theradionuclide does not leave the distal arm until the cuffis released.

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Inject the contents of one vial of stannous pyrophosphatecontaining 1 milligram of stannous chloride dihydrate.

Twenty minutes later, attach a 4-way stopcock (MEDEXNo. MX421) to a butterfly set and flush line with aheparin solution containing 10 units per milliter(100 units in 10 ml normal saline attached to one arm ofthe stopcock). Insert a butterfly needle set into thepatient’s peripheral vein.

Affix a 6 ml shielded syringe containing 740 MBq of99mTc pertechnetate to the free port on the stopcock.

Withdraw 3 ml of whole blood through the heparinizedcatheter into the syringe containing the pertechnetate.Invert gently several times.

Flush the catheter using the dilute heparin solution.

Incubate the red blood cells and pertechnetate for at leastten minutes with occasional mixing.

Inject using bolus technique for flow studies.

Remove injection apparatus and dispose in radioactivewaste.

Modified Methodfor

The In Vivo Labelingof

Red Blood Cells withTechnitium

Single Photon EmissionComputed Tomography

Single Photon Emission Computed Tomography (SPECT)has been demonstrated to improve image contrast instudies where overlying or underlying activity makesstandard planar scintigraphy difficult to interpret.

The raw data for a SPECT study consists of a set ofprojections collected by a gamma camera capable ofrotating around the long axis of the patient. These pro-jections can be collected over either 180 or 360 degrees.

SPECT requires an increased vigilance in both qualitycontrol procedures and patient data collection procedures.An active quality control effort is necessary to ensureadequate camera uniformity, patient positioning, isotopepeaking and other related items which simply do notmatter as much in conventional planar imaging.

Necessary Quality ControlA current valid data calibration set consisting of: centerof rotation (COR) data, gain (mm/pixel), and uniformitycorrection mask.

RadiopharmaceuticalsAll

Time of ImagingConsistent with standard planar study requirementsstriking a balance between adequate count density andpatient motion artifacts.

Maximum patient tolerance is approximately 40 minutes,but most SPECT acquisitions are between20 - 30 minutes.

Patient PreparationThe patient should understand the importance of holdingstill for the entire study. The camera’s motion should bedemonstrated to the patient during positioning.

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Patient PositioningThe goal is obtain the minimum radius circle about thepatient that contains all of the area of interest in eachprojection.

Usually the patient’s forearms are elevated above theirhead and rest on their forehead. About half way throughthe study, the position of the arms are carefully switched.This decreases overall the patient to camera distanceand allows a smaller radius to be used.

At least one complete manual rotation of the camera atthe final radius of rotation must be performed to ensurepatient safety and camera clearance during the imagingsequence.

With the newer cameras, auto-contouring is possible (seesection on auto contouring for SPECT acquisitions).

Final SPECT ChecklistPrior to initiating the scan, a final check must be madeof all camera controls:

SPECT Orientation

Peak and Window (15%) Set

Mag Setting: Center

Make sure that COR and uniformity correctionsare current.

Set number of projections

Set time per projection

Set 180 or 360 degree acquisition

Record patient data

Number of AnglesFull circle rotations with the MS-2 cameras areacquired with 96 angles fir each head. Halfcircle collections are also acquired with 96angles for each head.

Time per ImageThe accompanying chart indicates total studytimes for combinations of image times andnumber of angles.

Degrees of RotationGenerally 201Tl is imaged over 180 degrees.All other radiopharmaceuticals are imagesover 360 degrees.

Flood CollectionAll studies must be flood collected using thecurrent calibration data set. If there are ques-tions about this, please check to see which dataset is current. This step is important.

Computational AnalysisAfter acquisition, the projection data is reconstructedusing a standard filtered back projection algorithm.

Prior to reconstruction, make sure that the flood and CORcorrections are turned on and that data from the correctnumber of camera heads is being reconstructed.

For most applications, an order=7 Butterworth filter isused for reconstruction. The frequency cut-off isdependent on the particular radiopharmaceutical that isbeing imaged.

As a general guide, the following values have proven tobe useful:

Bone 0.7, Brain 0.6, 67Ga and 111In 0.4.

Different filters can be tested with filter selectionroutine on the ICON computer. If you are not sure of thecorrect filter to use, make your best guess and reviewthe results with the staff physician.

For brain SPECT studies, attenuation correction shouldbe performed using the Chang algorithm on the ICONcomputer.

SPECT data acquired for other areas of the body shouldnot be attenuation corrected.

Data AcquisitionBecause SPECT collections require specifying manypieces of information a study should be plannedahead of time.

The following choices must be made:

Matrix SizeMost SPECT studies are acquired with a128 x 128 matrix, however for low countcollections (e.g., 201Tl) a 64x64 matrix may bepreferable.

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Miscellaneous

Quality Control Procedures forScintillation Cameras

PolicyGoalsThe quality control program has two goals:

Examination of the cameras for potentialsafetyhazards.

Examination of the performance of scintillationcameras when imaging test objects.

Quality assurance and safety checks will be made inaccord with the protocols described below, under thedirection of the operation manager. The operationmanager will review the performance of the instrumentsdaily, monthly, and/or quarterly and record the results ofhis/her review.

In the event that a malfunction or safety hazard isdetected, the operation manger is responsible forinitiating actions to remedy the problem.If the problem is deemed to be serious, either in terms ofdegraded image quality or poses a safety hazard, theoperation manager will terminate the use of theinstrument until the problem is remedied.

The quality assurance and safety program includeschecks on each camera which are performed daily,before the start of patient examinations, and monthlyand/or quarterly as indicated below. The results of thesechecks and measurements will be preserved as a recordand will be available for quarterly review witha radiological physicist.

Daily Camera Quality ControlQuality Control is to be performed prior to the start ofpatient studies. Each technologist will be responsiblefor performing daily QC on their camera, or it will be upto the individual who may be using the camera first.

QC is to be performed in accordance with the hand outyou received. This will consist of an extrinsic uniformityflood performed daily with resolution phantom performedonce a week.

There are predefined acquisitions set up named DAILYQC on each system. This information is to be documentedin the binder assigned to each camera.

Each camera has a Patient header named “Daily QC”,with the name of the camera. Please select this headerto acquire all floods in order to make record keeping andbacking up simple. If you have any questions, pleaseconsult operation manager, George Desko.

Scintillation Camera Safety

Report any problems to the operation manager immediately.

Protocol

Check the movement of the camera head. Does it movesmoothly and respond to the controls? Are there anyloose knobs or dials or dials on the console? Check forfrayed or cut cables. Are all cables fixed in place sothat movement of personnel or patients in the vicinityare not impeded?

If the camera scans in a rectilinear motion, this move-ment should also be checked. If the camera headrotates for SPECT imaging, check that the rotation willnot be impeded by objects in its path. Make sure thatno objects impede the scan motion.

The camera head should also be checked to ensure thatthe collimator is firmly attached; there should be no looseor missing attachment fixtures (e.g., nuts or bolts). Checkthe patient bed. Make sure that it is clear of extraneousobjects and firmly set in place.

Safety checks should be performed daily.

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Miscellaneous

Daily ProceduresThe daily procedure checks the:

Energy spectrum,Field of uniformity, andImage display and/or photography system

Most cameras will be checked with a uniform floodphantom, with the 99mTc-collimator in place.

ProtocolPlace the camera head so that the collimator is facingupward and level. An intrinsic flood can be performedinstead, check with the operations manager for details.

Place an absorbent sheet on the collimator to protectagainst radioactive contamination.

Place the flood source on the absorbent sheet so thatthe center of the source coincides with the center of thecollimator.

Set the pulse height window to 20% and center it on thephotopeak for either 57Cobalt-57 or 99mTc - as appro-priate. Check the centering of the peak and record thesetting. This setting should not change much from dayto day. If unusual changes are noted, inform the opera-tions manager. Record and inspect a pulse heightspectrum. Verify that the photopeak is clearly viable.

Note the count rate. This count rate should be less than20,000 CPS and it should not vary appreciably from dayto day if the same flood source and collimator are used.Report variations in count rate of 10% or more to theoperation manager.

For small field-of-view cameras:1 million counts should be recorded.

For large field-of-view cameras:At least 3 million counts should berecorded.

Inspect the flood image. When inspecting the uncorrectedflood image, some variation is acceptable, but there shouldbe no regions which are very dark or light. The correc-tion flood should appear uniform.

Place a film recording of the flood image in the QC binderfor each camera.

Quarterly ProceduresStationary Cameras

For each camera and each collimator used on thatcamera, acquire a 20 million count flood with and/or with-out the correction circutry switched on. (Switching thiscircuit on and off is not possible on some cameras.)Use a computerized acquisition and display if available.

For SPECT cameras with multiple heads, uniformitymeasurements should be made for each head.

Inspect the images for defects. Defects appearing atthe same location probably arise from nonuniformityproblems in the camera. Defects which appear on asingle image or move from place to place indicatedamage to the collimator(s).

If the computerized data system has QC software,remove the collimator and use a point source to measureuniformity and run that program to determine theintegral and differential uniformity. The operationmanager and/or physicist should review these data forthe quarterly report and ensure that the camera isoperating within specifications.

Place recording of this information in the QC binder foreach camera.

For each camera, measure the designated resolution phan-tom. Usually this procedure will be performed with thecollimator removed. Bar phantoms or line phantoms canbe used. If computerized acquisition and/or analysis isavailable it should be used.

Quality Control Proceduresfor

Stationary and SPECT Cameras

Acquire a flood image. If there are correction circuits,record the flood twice, with the circuits switched offand on (if applicable). If the camera is connected to acomputerized data system, it should be used. In addi-tion if analog images are used for patient studies, theflood image should also be recorded using that display.

542

CLINICAL PRACTICES

Miscellaneous

For bar patterns, collect 20 million events.

Use an appropriate source, so the count rate is below20,000 cps. Examine the patterns. Are lines visible inall quadrants? All but one? In the latter case, comparewith acceptance testing or last quarterly check. Checkthe image for linearity. Nonlinearity is evident when thelines are wavy. Barrel or pincushion distortion may alsobe present and should be noted.

Use the SPECT collimator for clinical imaging with 99mTc.

Use the clinical reconstruction parameters used for brainimaging with 99mTc.

Check resolution against acceptance data. Images of rodsources should be round.

Check uniformity with attenuation correction. Bulls eyepatterns should not be visible.

Record images and place in QC binder.

Monthly Procedures SPECT Cameras

Perform the center of rotation procedure, as describedby the manufacturer of the SPECT camera.

Acquire and reconstruct images of SPECT resolution/uniformity (Jasczak) phantom. If possible, place thephantom on an extender so that it does not rest on thepatient bed. In some cases you may use the patienthead rest as support, with the phantom taped in place.

Set the radius in rotation (or position heads on multiplecameras) to 10 cm, or just big enough to clear thephantom.

Manually test the head rotation to ensure that thecamera can rotate freely.

Acquire at least 500,000 events at each angle. Use aclinical acquisition procedure, making sure that theacquisition is performed in 128 x 128 format and withat least 64 angular steps. Keep the count rate under20,000 cps.

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NUCLEAR MEDICINE

Camera Number:

Manufacturer:

Date:

Evaluation of uniformity:

Evaluation of Resolution:

Evaluation of Linearity:

Evaluation of SPECT performance:

1) Uniformity

2) Resolution

Reviewed by:

Operation Manager: Physicist:

QUALITY CONTROL REPORTfor

SCINTILLATION CAMERAS

544

CLINICAL PRACTICES

DAILY QUALITY CONTROL LOGfor

SCINTILLATION CAMERAS

CAMERA NAME / NUMBER:

DATE ENERGY COUNT COLLIMATOR SAFETY FLOOD SIGNATURE SETTING RATE CHECK QUALITY

545

NUCLEAR MEDICINE


Imaging of Cellular Injury

Antimyosin Imaging of

Infarct, Myocarditis, and

Transplant Rejection

Antimyosin is an antibody fragment directed againstcardiac myosin. Cardiac myosin is only available forbinding with its antibody when the cardiac muscle cellshave been damaged. Under such conditions, holesdevelop in the cell membrane and the myosin fibrilsbecome exposed circulating antimyosin.

Because antimyosin binds to myosin in areas of irrevers-ibly damaged cardiac muscle cells, it can be used as amarker for myocardial cell necrosis in infarction,myocarditis, and heart transplant rejection.

Instruments and EquipmentLarge field of view camera with medium energycollimator.

Radiopharmaceutical111-In antimyosin

Time of ImagingImaging performed 72 hours post injection for planarimaging. If SPECT is used, it should be performed at 48hours post injection.

Dose111-In antimyosin = 74 MBq


Patient ImagingStatic Images: Anterior and 45o LAO views, 20

minutes each.

SPECT: Optional on staff physician discretion.Prior to SPECT imaging, planar anterior andLAO images should be recorded for 10 minuteseach.

Imaging of Ventricular Function

Gated Cardiac Blood Pool Gated First Pass and Equilibrium

To evaluate overall size and global and regional functionby use of an intravascular label and a scintillationcamera operated in synchrony to the patient’s cardiaccontractions.

Instruments and EquipmentRegular or large field of view camera accompanied by acomputer. Use general all purpose collimator for entirestudy.

Radiopharmaceuticals99mTc Red Blood Cells

99mTc human serum albumin (HSA) may be used for:portablestudies;other patients who have limited I.V. access,after approval by staff physician.

Time of ImagingInitiate upon injection of labeled red cells.

Dose740 MBq - AdultWebster’s Rule - Pediatric

NUCLEAR CARDIOLOGY

546

CLINICAL PRACTICES


Patient Preparation99mTc Red Blood Cells

Reconstitute vial of stannous pyrophosphate with3 milliliters of saline. Dispense entire vial of reconstitutedsolution into syringe and inject intravenously into patient.

Wait 20 minutes.

Insert 19 gauge butterfly into right arm vein and with-drawn exactly 3 ml of blood into shielded 6 cc syringecontaining 740 MBq Tc99m with heparin and saline andinvert several times. Allow to incubate in syringe for atleast 10 minutes.

Please note that syringes are to be kept warm in specialholder- refer to tagging procedure.

While tagging is occurring place electrodes on patient;one below each clavicle and one over the left side belowthe rib cage.

99mTc human serum albumin will be prepared by theRadiopharmacy.

AdministrationBolus injection with 10 ml saline flush.

Patient PositioningGated flow study using Oldendorf technique in the 30oright anterior oblique (RAO).

30o-60o left anterior oblique (LAO), whichever bestshows uniform septal thickness. (This insures LVEFmeasurement if study terminated early.)

Anterior.

Left Posterior Oblique (LPO) with patient prone, [patientmay be done prone], patient may be done on right sideonly as a last resort. The left ventricle should be in thehorizontal position and seen in its long axis.

Data AcquisitionAcquire 5cm Co57 marker image, during LAO projection.

Technicare Camera/ON seriesType “POP” and select Utilities partition.

Under Utilities select “Cardiac”. Insert a preparedpatient disk and mount in drive.

To create a new study header type (WRITE) and select(CREATE A NEW STUDY), and type in patientinformation.

Depress CTRL 1 (Function Button 1) and followcommands.

If the ECG tracing and interval are correct say yes andremember the interval as this will be typed in again forthe left side of flow study.

Before injection is being done using Oldendorf techniquepress return and type in given interval again and pressreturn.

Inject.

As the activity begins to fill in the lungs wait approxi-mately 4 sec. and press CTRL S. This will automaticallystop acquiring the right side of study.

Press camera start/stop to acquire left side of study. (Insome cases the patients transit time will be extremelyrapid or slow, use your own discretion for starting andstopping acquisition).

When this is completed write information to disk. Type(WRITE) and select current study (C) you will have3 choices under current study, select New Set andanswer questions.

Label for images: View completed. Starting image number: H Byte (B) or Word (W): W Number of Frames: e.g. 32 for First Pass

and LAO.To complete the other 3 views type MGAQ and answerthe following questions:

Continue processing commands: N Stop acquisition: D Stopping density: 300 for

Ant., and LPO, 200 for LAO. Enable tracking: N

Frames: 18 framesper view for Ant and LPO;32 for LAO.

Write to disk only the first 16 frames.Transfer to Siemens ICON system using NUMA computer.

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Computational AnalysisEjection fraction analysis is required upon completion ofthe study.

If processing Technicare System then follow steps below.

To recall an image set:To Type (READ) and select (CURRENT) study.Choose image set number.Starting image number: H1

Recall the LAO view to do the ejection fraction analysis.

Normalize entire set of frames (CNTN H1, H1:16).

Gradient MICA is routinely used for analysis.

Do SUM frames — to check number of counts/frames. Ifthe difference is global counts between the first and lastframe exceeds 15%, then perform count normalization(CNTN) prior to the ejection fraction analysis.

Type (MICA G) and answer questions.Frames: (H1 :16)Wish to smooth images: (Y)Create background: Background should betaken at about 3 o’clock to the left ventricleavoiding the aorta and spleen.

After background subtraction set box to encompassentire left ventricle avoid surrounding structures. Onceyou have done this the computer will automatically stepthrough each frame and calculate an ejection fraction.

Photograph the result.

Along with ejection fraction analysis, stroke volumeimages of the anterior and LAO should be taken withoriginal date. To do a stroke volume (MOV) the endsystolic frame to H2, and press (CTRL 3), functionbutton 3.

Comments: Obtain stroke volume of each Anterior andLAO projection and photograph along with end systolicand end diastolic images.

Siemens ICON SystemTake disc from O-N computer and insert in NUMASystem computer in interpretation room. Follow screeninstruction and select Technicare 5.25 floppy option totransfer data and register patient in ICON database.

Once patient’s study has been transferred to ICONsystem, use Auto-EF program to obtain ejection fractionmeasurement. Auto-EF output should be confirmed byvisual inspection of the data and if questionable repeatedusing manual mode.

To record data to determine right and left ventricularfunction within 30 seconds of injection. This procedurecan be done at rest or in conjunction with exercise orpharmacologic stress.

Instruments and EquipmentGamma camera with all purpose parallel hole collimatoror with the 30 degree slant parallel hole collimator.Computer equipped with a fixed disk drive (to record dataat high rates) (MCS-560 or equivalent with a Winchesterdrive).

RadiopharmaceuticalTc-99m RBC; Tc-99m DTPA.

Time of ImagingIn concert with injection.


Patient PreparationNone (with DTPA or pre-administration of stannoussolution if RBC’s are used).

AdministrationOldendorf injection through a large antecubital vein.Data acquisition should commence prior to injection.

Ungated First Pass Ventriculogram

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CLINICAL PRACTICES


Patient PositioningPatient is placed supine. The camera is rotated to a30 degree RAO position when the parallel hole collima-tor is used or in the anterior position with the slant holecollimator rotated to achieve a 30 degree RAO position.

Check location of the heart in the field by moving a sourcefrom the right sternal border to the point of maximalimpulse of the LV and from the xiphoid to the angle ofLouis.

Data AcquisitionSet camera for Tc-99m with a 30% window. Setcomputer for a disk acquisition (DSKAQ) for a preset timeof 50 milliseconds/frame in a hexant (64x64) acquisitionfor a total 1200 frames (60 seconds) in byte mode.

Start computer 1-2 seconds prior to injection.

After acquisition is completed — computer will providemessage “RECONFIGURATION DATA SET” — only afterthis is completed can the data be reviewed.

Computational AnalysisPerform read+ 1,1,H1:100 to add to the first 100 frames(3 seconds) of data to flag the region of the RA and RV.

Draw the RA and RV regions of interest. Perform read+1,1000,H2:100 to add 100 frames of data for assess-ment of LA and LV.

Perform SETR with RH1, etc. to flag atria and ventricles.The curves for RV and LV will have to be generatedseparately, since the curve program can only handle 256frames.

Smooth the curves 3 times. Analyze for the peak counts(end diastole) and minimum counts (end systole)/cardiaccycle.

To disclose abnormalities in cardiac function that mightnot normally be seen without physiologic stress.

Instruments and EquipmentRegular field of view camera with computer. 12 leadECG machine. GAP collimator.

Time of ImagingImmediately after injection of labeled RBC’s.


Patient PreparationInject pyrophosphate in saline. Wait 20 minutes thentag red blood cells as described previously in the gatedcardiac protocol.

Exercise Radionuclide Ventriculogram

AdministrationThe first pass technique does not have to be done in thisprocedure unless there is a question regarding rightventricular function or valvular disease. Must beperformed in exercise laboratory.

Patient PositioningObtain a routine ANT and LAO gated study.

Place patient in a supine position for the stress, and havethe ECGtech place the remaining leads on the patient.Obtain an LAO view, for 3 minutes. This will be yourpre-exercise.

Check with cardiac coordinator or cardiac fellow todetermine if an LPO is necessary. This can be done upon completion of the exercise portion of test.

Data AcquisitionUse GAP collimator and 30% window for exerciseportion.

(POP) Utilities partition and select (Cardiac) set.

For acquiring the stress, function button numbers6 and 8 are used.

Upon completion of the pre-exercise study, the ECG techwill set the initial resistance on the ergometer to 25 watts(150 KPM).

Radiopharmaceuticals99mTc Red Blood Cells.

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Patients should exercise at a steady rate of 60 revolu-tions per minute, for 1 minute stage.

When patient reaches 75% of predicted maximum (CTRL6) and follow commands, obtain an LAO view for3 minutes. When this is complete, position camera foran anterior view for the same time, using (CTRL 6).

CTRL F), this will allow the last cardiac cycle to becompleted.

Depress (CTRL 8). It will then ask “LABEL FOR IMAGES”and fill in label, eg. PREEX, anterior and LAO, and hitreturn. Study will now be written to disc.It is important that the ECG electrodes are securely onpatient so that there is no artifact signal detected bycomputer. Irregular gating can cause misinterpretationof a study.

This study may be performed with pharmacological stressusing dobutamine and either planar or SPECT imaging ofthe cardiac blood pool. Details of the dobutamine stressprotocol and SPECT imaging of the cardiac blood poolare given below.

Computational AnalysisEjection fraction analysis should be performed on the pre-exercise, pre-max and maximum exercise views. Strokevolume images on the anterior and LAO views should betaken also.

Gated SPECT - Myocardium

To assess regional wall thickening and motion as well asglobal left ventricular function simultaneously withmyocardial perfusion.

Instruments and EquipmentSiemens orbiter or MS-3 with an all purpose parallel holecollimator.

RadiopharmaceuticalTc-99m-MIBI.

Dose900 MBq - adultWebsters Rule -Pediatric


AdministrationInject Tc-99m-MIBI with the patient at rest.

Patient PositioningSupine on SPECT imaging table.

Data AcquisitionSet camera pulse height analyzer for Tc-99m with a 20%window. Choose pre-set acquisition protocol for gatedSPECT from ICON menu. Pre-set acquires 64 angles at8s/view.

Be sure data are stored as indicated by computer displayand audible signal before attempting to reconstruct andview images.

Computational AnalysisScans are viewed using gated SPECT display programwhich permits visual as well as semi-quatitative analysis(regional wall thickening and global ejection fraction) ofthe data.

Regions with reduced blood flow at rest will appear aszones of reduced tracer activity and so may be difficultto analyze. Gated SPECT of the cardiac blood pool (seebelow) may be more appropriate in such cases.

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Gated SPECT - Cardiac Blood Pool

To assess global and regional wall motion of right andleft ventricles.

Instruments and EquipmentSiemens orbiter or MS-3 with an all purpose parallel holecollimator.

RadiopharmaceuticalTc-99m-RBC’s (modified in vitro label).



AdministrationInject Tc-99m-RBC’s with the patient at rest.

Thallium - 201 Rest and Redistribution

To evaluate myocardial perfusion at rest, using a radiola-bel which is taken up rapidly by normal myocardial cells.

Test is useful to evaluate myocardial viability which isindicated either by a reversible rest defect or fixeddefect of only mild/moderate intensity.

Instruments and EquipmentRegular field of view camera with all purpose collimatorand computer.

Patient PositioningSupine on SPECT imaging table.

Data AcquisitionSet camera pulse height analyzer for Tc-99m with a 20%window. Choose pre-set acquisition protocol for gatedSPECT from ICON menu. Pre-set acquires 64 angles at8s/view. Be sure data are stored as indicated by com-puter display and audible signal before attempting toreconstruct and view images.

Computational AnalysisScans are viewed using gated SPECT display programwhich permits visual as well as semi-quatitative analysis(regional wall motion and contraction by FourierAnalysis which creates phase and amplitude images) ofthe data.

Use in place of gated SPECT Tc-99m-MIBI in case wereresting perfusion defects are likely.

Myocardial Perfusion Imaging

RadiopharmaceuticalThallous - 201 Chloride

Doseweight < 180 lb - 80 MBqweight 180-200 lb - 100 MBqweight > 200 lb - 120 MBq

DO NOT EXCEED 130 MBq TOTAL ADMINISTERED DOSE.

Time of Imaging10 minutes post injection of Thallium-201; Delayscompleted 3-4 hours later.

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SPECT AcquisitionNumber of angles to collect. Half circle (180o)collections use 64 angles.

Time per image: For men >200lbs; Women>175lbs.

Initial DelayMS-3: 25s/view-stress and 20s/view restOrbiter: 20s/view-stress and 15s/view restElScint: 20s/view-stress and 15s/view rest

Patient PreparationIt is not necessary for patient to fast before test.Patient should be injected in the upright position whenpossible. If patient is on an intra-aortic balloon pumpcheck with physician about whether or not patient shouldremain on pump for the study. May be performed atbedside.

AdministrationDirectly into a vein, if not possible a peripheral line maybe used providing no medication is running through it.Consult nurse if you are not positive.

Patient PositioningPlanar, typically portable.

Initial Anterior H1, Delay H2LAO 50o H5, Delay H6LAO 70o H9, Delay H10

Data AcquisitionUsing 80 keV Tl201 photopeak with 25% window,10 minutes per view.

If peak count density of left ventricle reaches 400 counts/pixel on the initial view in less than 10 minutes, takeremaining images for the shorter time interval. Recordtime for images on clinic sheet.

Time per image: For men<200lbs; Women<175lbs.


64x64x8 matrix

Special Planar ViewsIt may be necessary to obtain an additional LAO imagewith patient in a right lateral decubitus position toeliminate diaphragmatic attenuation.

CommentsThallium-201 is a low energy isotope. Attenuation isusually seen in heavy or muscular people, and especiallyin women. Effort to reduce attenuation should be madeby placing the breast toward the center of the chest onoblique views. Record time of injection and time ofdelayed imaging.

Computational AnalysisPlanar:Normalization of images for interpretation and recordingon film. Read initial and delayed data sets (usuallywritten together in the delayed set on disk). MOV Q1 toQ2, MOV Q3 to Q4.Use the baseline knob to determine the upper 10% ofcounts in the myocardium in the initial and delayedimages. Ratio the baseline counts of the initial todelayed. Use the ratio value to multiply the delayedimage in that projection.

SPECT:Images are reconstructed by the technologist at the workstation of each computer. For Tl-201 SPECT reconstruc-tion default parameters are: Butterworth filter with cut-off = 0.5 and order = 8.Use Comparison display option to photograph which isaccomplished over network link from Mac-ICON to Heliosprinter.

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Note: This procedure is done routinely using doses thatare greater than those listed in the manufacturer’s pack-age inserts. The choice of the radiopharmaceutical andthe dose for each procedure described in this Manual ismade by the physician staff of Nuclear Cardiology, inorder to acquire the best results while complying withMGH Isotope and/or Pharmacy Committee guidelines. Thename of the nuclear cardiology physician ordering anytest that is listed here is maintained in the files of theradiopharmacy with the data on the patient andradiopharmaceutical.

Thallium-201 Exercise Stress with Reinjection

See also Stress Testing and Cardiac Emergencies

To assess myocardial perfusion by a radiolabel which istaken up by intact myocardium roughly in proportion toblood flow.

In conjunction with a stress test, coronary blood flowreserve can be judged.

Instruments and EquipmentAny regular field of camera accompanied with acomputer using general all purpose collimator (GAP).

For SPECT use Orbiter, ElScint or MS-3.

RadiopharmaceuticalThallous-201 Chloride

Doseweight < 180 lb. - 80 MBq

weight 180 - 200 lb. - 100 MBqweight > 200 lb. - 120 MBqDO NOT EXCEED 130 MBq TOTAL ADMINISTERED DOSE.

Time of ImagingCommencing not more than five minutes after injection.

Patient PreparationPatient should be fasting before exam and remain fast-ing except for water until initial images are completed.

Start I.V. with 0.9% saline, except in the case of ahypertensive person were D5W is to be used.

Insert 21 gauge intracath into right arm, avoid using theantecubital fossa unless absolutely necessary. Must beperformed in exercise laboratory.

AdministrationWhen instructed by the cardiologist, inject the thalliuminto the diaphragm of the I.V. tubing clamping off thetubing proximal to the diaphragm to prevent the thalliumfrom backing up into the tubing.

Once injected, open I.V. fully and let run until patient ismoved to stretcher, then I.V. can be slowed down. Oncethe 2 minute ECG is complete remove all electrodesexcept the limb leads, and move patient under camerafor imaging.

Patient PositioningPlanar:Initial images anterior H1, 50o LAO H5, 70o LAO H9.Delayed images anterior H2, 50o LAO H6, 70o LAOH10.

SPECT:Patient supine on imaging table of SPECT camera.

Data AcquisitionPlanar:

Using 80 keV Tl-201 photopeak with 25% window,10 minutes per view; if peak count density of leftventricle reaches 400 counts/pixel on the initial view inless than 10 minutes, take remaining images for the sametime interval. Write digital data to disc and record timefor images on clinic sheet.

SPECT:

Number of angles to collect. Half circle (180o)collections use 64 angles.

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Time per image: For men >200lbs, Women>175lbs.


Time per image: For men<200lbs, Women<175lbs.


64x64x8 matrix

When patient returns about 2-4 hours later, a secondinjection of 37 MBq of thallium is administered with thepatient sitting quietly.

Approximately 5 minutes after injection, the secondseries of images are recorded in the same positions asthe initial series. Retrieve the initial study from disk andrecord delayed images.

Computational AnalysisPlanar

Normalization of images for interpretation and recordingon film: Read initial and delayed data sets (usually writ-ten together in the delayed set on disk). MOV Q1 to Q2,MOV Q3 to Q4. Use the baseline knob to determine theupper 10% of counts on the initial and on the delayedimages. Use the ratio value to multiply the delayedimage in that projection.

SPECTImages are reconstructed by the technologist at the workstation of each computer. For Tl-201 SPECT reconstruc-tion default parameters are: Butterworth filter withcutoff=0.5 and order=8. Use Comparison displayoption to photograph which is accomplished overnetwork link from Mac-ICON to Helios printer.

Note: This procedure is done routinely using doses thatare greater than those listed in the manufacturer’s pack-age inserts. The choice of the radiopharmaceutical andthe dose for each procedure described in this ProcedureManual is made by the physician staff of Nuclear Cardi-ology, in order to acquire the best results while comply-ing with MGH Isotope and/or Pharmacy Committee

guidelines. The name of the nuclear cardiologyphysician ordering any test that is listed here is main-tained in the files of the radiopharmacy with the data onthe patient and radiopharmaceutical.

Dipyridimole Thallium Stress Study

withReinjection

RadiopharmaceuticalThallium 201; Persantine - use IV infusion pump andadminister total dose of 0.56 mg/Kg over 4 min (142mcg/Kg/min X 4 min).

Instruments and EquipmentStandard Tl-201 three view images with regular field ofview camera and computer.

Time of Imaging0 min - Begin infusion, monitor HR, BP, ECG Q 1 min(note side effects) — severe symptoms (chest pain,nausea/vomit, profound drop in BP, etc. reversedAminophylline IV, 25-250 mg (usually 50 mg).

4 min - D/C Persantine infusion. Continue 0.9% NSinfusion. Continue to monitor BP/P. Exercise by walkingat zero grade on treadmill to raise BP to at least baselinelevel.

10 min - Inject Tl 201. Continue IV in wide open drip for2 minute and then maintain open at 1 ml per minute.

18 min - Begin imaging.

Doseweight < 180 lb. - 80 MBq

weight 180 - 200 lb. - 100 MBqweight > 200 lb. - 120 MBq

Thallium 201 IV 74 MBq, use 20-22 angiocath, maintain0.9% NS drip.

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Patient PreparationPatients should be fasting prior to this examination.Nothing to eat or drink for at least 6 hours, and no majormeal for at least 12 hours. A light meal or clear liquidsare acceptable up to 6 hours before the examination.

Persantine by IV infusion pump (142 mcg/Kg/min X 4 min).

Resting BP-HR x2.

Patient PositioningSupine on table with peripheral and 12 lead ECG.

AdministrationFill infusion syringe with Persantine and saline to a totalvolume of 50ml.

Flush line (15 ml vol); and begin infusion 4 minutes.

Total dose: 0.56 mg/kg over 4 minutes.

CommentsAminophylline reverses the side effects of Persantine.Usually no more than 100 mg need to be given IV.

ALL patients are to be given 50mg Aminophylline atcompletion of first image.

Data AcquisitionPlanar:

Using 80 keV Thallium-201 photopeak with 25% win-dow, 10 minutes per view; if peak count density of leftventricle reaches 400 counts/pixel on the initial view inless than 10 minutes, take remaining images for theshorter time interval. Record time for images on clinicsheet.

SPECT:

Number of angles to collect. Half circle (180o) use 64angles.

Time per image. For men >200lbs, Women>175lbs.

Initial DelayMS-3: 25s/view-stress and 20s view restOrbiter: 20s/view-stress and 15s/view restElScint: 20s/view-stress and 15s/view rest

Time per image: For men<200lbs, Women<175lbs.


64x64x8 matrix

Computational AnalysisPlanar:

Normalization of images for interpretation and recordingon film: Read initial and delayed data sets (usually writ-ten together in the delayed set on disk). MOV Q1 to Q2,MOV Q3 to Q4. Use the baseline knob to determine theupper 10% of counts of initial to delayed. Use the ratiovalue to multiply the delayed image in that projection.

SPECT:

Images are reconstructed by the technologist at the workstation of each computer. For Tl-201 SPECT reconstruc-tion default parameters are: Butterworth filter withcutoff=0.5 and order=8. Use Comparison displayoption to photograph which is accomplished overnetwork link from Mac-ICON to Helios printer.

Note: This procedure is done routinely using isotopedoses that are greater than those listed in themanufacturer’s package inserts. The choice of theradiopharmaceutical and the dose for each proceduredescribed in this Procedure Manual is made by the physi-cian staff of Nuclear Cardiology, in order to acquire thebest results while complying with MGH Isotope and/orPharmacy Committee guidelines. The name of the nuclearmedicine physician ordering any test that is listed here ismaintained in the files of the radiopharmacy with thedata on the patient and radiopharmaceutical.

Alternative Forms of Pharmacological StressAdenosine and Dobutamine.

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Thallium Adenosine/DobutamineStress with

Reinjection

Adenosine Stress TestsRecommended Protocol

The patient walks on the treadmill at 0% grade at0.7 - 1.7 MPH depending on physical condition.

As soon as the patient begins walking and it is clear he/she can maintain the selected pace begin adenosineinfusion (140 ug/Kg/min X 5min by IV infusion pump).

At 2 minutes of adenosine infusion inject tracer (thalliumor Tc-99m-MIBI) and continue infusion for 3 additionalminutes provided no adverse effects occur.

Discontinue adenosine after the 5th minute of infusionbut continue to have the patient walk for 2 additionalminutes after adenosine has been turned off.

Exceptions/Special Cases

Patients who have had a stent placed within 4 weeks ofthe test may walk on the treadmill at 1.0 - 1.5 MPH and0% grade. If the patient cannot walk then arm weightsmay be used instead.

Elderly (> 80 years old) or any severely debilitatedpatient who cannot walk or use arm weights and whomay be at higher risk for high grade heart block withadenosine should be considered for dipyridamole instead.

Dobutamine Stress Tests

Stage Dose Duration (min) 1 10 mcg/kg/min 3 2 20 mcg/kg/min 3 3 30 mcg/kg/min 3 4 40 mcg/kg/min 3

Patients are studied in the supine position; no exercise isperformed. Dobutamine is given by IV infusion pump.Dobutamine solution is 250 mg dobutamine in 50 ml N/S(5mg/ml).

Isotope (Tl-201 or Tc-99m-MIBI) is injected at 11:00 ofthe protocol, or earlier if limiting symptoms develop.

Atropine 0.25 - 0.5 mg IV may be given at the discretionof the test supervisor if the heart rate responseto Dobutamine is well below 85% predicted maximum.Maximum dose = 2.0 mg.

Metoprolol 2.5-10.0 mg may be given IV to reverseDobutamine-related side-effects or ischemic ECGchanges.

See also Stress Testing and Cardiac Emergencies

To assess myocardial perfusion by a radiolabel which istaken up by intact myocardium roughly in proportion toblood flow. In conjunction with a stress test, coronaryblood flow reserve can be judged.

The stress test employed will vary with clinicalcircumstances and may use any of the following:

Treadmill exercise

Adenosine

Dipyridamole

Dobutamine.

Instruments and EquipmentAny regular field of camera accompanied with acomputer using high resolution collimator on MS-3, Gapcollimator on Elscint and Orbiter. For SPECT use Orbiter,ElScint or MS-3.

RadiopharmaceuticalTc-99m-MIBI

Dose296 MBq at stress and 888 MBq at rest.

Tc-99m-MIBI Exercise Stress Study

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Time of ImagingCommencing at least 30 minutes after stress injectionand at least 60 minutes after rest injection. If hepaticactivity exceeds myocardial activity, imaging should bedelayed an additional 30 minutes, whenever possible.

Patient PreparationPatient should be fasting before exam and remain fast-ing except for water until initial images are completed.

Start I.V. with 0.9% saline, except in the case of ahypertensive person were D5W is to be used. Insert21 gauge intracath into right arm, avoid using theantecubital fossa unless absolutely necessary.

The patient should be asked to refrain from eating (asmuch as possible) between initial and delayed images.

AdministrationWhen instructed by the cardiologist, inject the tracer intothe diaphragm of the I.V. tubing clamping off the tubingproximal to the diaphragm to prevent the tracer frombacking up into the tubing.

Once injected, open I.V. fully and let run until patient ismoved to stretcher, then I.V. can be slowed down.

Patient PositioningPlanar:

Initial images anterior H1, 50o LAO H5, 70o LAO H9.Delayed images anterior H2, 50o LAO H6, 70o LAOH10.

SPECT:

Patient supine on imaging table of SPECT camera.Data AcquisitionPlanar:

Using 140 keV Tl-201 photopeak with 20% window.Target mean count density over left ventricle of 700counts/pixel on the initial view in less than 10 minutes,take remaining images for the same time interval.

Write digital data to disc and record time for images onclinic sheet. Use 64x64 word mode matrix. While aprecise mean count density is dificult to determine, the700 CTS/MIN figure should apply to normal myocardium,not for example, to a “hot” Papillary muscle.

SPECT:

Because an SPECT collection requires specifying manypieces of information an SPECT study should be set upahead of time.

The following parameters are “hard-wired” in pre-definedprotocols:

Number of angles to collect. Half circle (180o) use 64angles.

Time per image. For men >200lbs, Women>175lbs.


Time per image. For men<200lbs, Women<175lbs.


64x64x8 matrix

After completion of initial scans the patient, whilesitting quietly, is given a second injection of 888 MBq ofTc-99m-MIBI.

The patient returns 1-2 hours later and the secondseries of images are recorded in the same positions asthe initial series. Retrieve the initial study form disk andrecord delayed images.

Computational AnalysisPlanar:

Normalization of planar images for interpretation andrecording on film: Read initial and delayed data sets(usually written together in the delayed set on disk).MOV Q1 to Q2, MOV Q3 to Q4. Use the baseline knob todetermine the upper 10% of counts on the initial and onthe delayed images. Use the ratio value to multiply thedelayed image in that projection.

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SPECT:

Images are reconstructed by the technologist at the workstation of each computer. For Tc-99m-MIBI SPECTreconstruction default parameters are: Butterworthfilter with cutoff=0.6 and order=8. Use Comparisondisplay option to photograph which is accomplished overnetwork link from Mac-ICON to Helios printer.

Tc-99m-MIBI Adenosine Stress

Tc-99m-MIBI Dipyridamole Stress

Tc-99-MIBI Dobutamine Stress

S e e

Thallium Adenosine/DobutamineStress

with Reinjection

And


See also Stress Testingand Cardiac Emergencies

S e e

Dipyridimole ThalliumStress Study

withReinjection

And



And

Tc-99m-MIBI Exercise StressStudy


S e e

Thallium Adenosine/DobutamineStress

with Reinjection

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CLINICAL PRACTICES


Vascular Shunt Imaging

Right to Left Shunt Angiographic Method

Premature appearance of injected label on the left sideof the circulation is an indication of R->L shunt; it maybe difficult to isolate the level of the shunt.

Instruments and EquipmentRegular field of view Anger camera equipped with an allpurpose collimator interfaced to a computer.

Radiopharmaceutical99mTc -labeled DTPA or RBC.

Time of ImagingImmediately

Dose400-800 MBq - adultWebster’s rule -pediatric


AdministrationBolus injection using Oldendorf technic and angiocath.

Patient PositionSupine. Anterior View.

Data AcquisitionAnalog - None

Digital - 64X64 matrix0.3 seconds DSKAQ for 200 frames after completion oracquisition. Data reconfiguration analysis is required.

This technique provides qualitative detection of R-L shunt.Recommend performance of study in LAO projection to

detect premature appearance of left-atrial/ventricularactivity.

Quantification requires much stricter acquisition terms.

Computational AnalysisSUM first, 50 frames. Set regions over superior venacava, right atrium, right ventricle, right and left lungs.Generate curves from each region for review.

ReferencePeter et al, Circulation 1981;64:572-577

Right to Left Shunt MAA Technique

There is minimal normal physiological shunting; thus mostof injected albumin micropheres should be trapped in thelung. The percentage found outside the lung relates tothe extent of R-L shunt.

Instruments and EquipmentRegular or large field of view Anger camera with allpurpose collimator interfaced to a computer.

RadiopharmaceuticalMacroaggregated albumin (less than 100,000 particleslabeled with 99mTc ; reduced if infant or child.

Dose150 MBq - adultWebster’s rule - pediatric

Time of Imaging Immediately after injection.

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Patient PositionSupine

Data AcquisitionQualitative technique:Anterior image of brain, palmar image of hand, or otherprojections as indicated by staff physician for 5 minutes.

Quantitative technique:Obtain whole body image on computer using ScanningWhole Body Camera at 5 cm/min.Flag whole body and lungs. Determine SUMR for each.Amount of R-L Shunt = 1 - [Lung/Whole Body]

Note: This procedure is done routinely for indicationsthat are not specifically listed in the manufacturer’s pack-age inserts. The choice of the radiopharmaceutical andthe dose for each procedure described in this ProcedureManual is made by the physician staff of Nuclear Cardi-ology, in order to acquire the best imaging results whilecomplying with MGH Isotope and/or Pharmacy Commit-tee guidelines. The name of the nuclear medicine physi-cian ordering any test that is listed here is maintained inthe files of the radiopharmacy with the data on thepatient and radiopharmaceutical.

ReferenceEditorial: Am Rev Resp Disease 1977;115:553-557

Left to Right Shunt

To determine the presence and magnitude of an intracar-diac or systemic-pulmonary shunt. The study is usuallyperformed with the patient at rest, but may be performedduring a physiological maneuver designed to increase themagnitude of the shunt.

Instruments and EquipmentGamma camera with an all purpose parallel holecollimator. Computer equipped with a fixed disk (torecord at high data rates).

RadiopharmaceuticalTc-99m RBC (washed).

Use conventional modified in-vivo approach, but washcells in syringe and re-suspend in saline prior tore-injection.

The maximum volume of the injectate should be <3ml.



AdministrationOldendorf injection through a large ante-cubital vein,preferably in the right arm.

Data collection should start prior to injection. Thequality of the vein and the optimization of injection arecritical to a successful study, since the detection of shuntdepends on assessment of the transit of the bolus throughthe cardiac chambers. A poor injection makes thisdetermination difficult, or impossible.

Patient PositioningRAO 30 degree view - unless the chest radiograph orEKG indicates marked cardiac rotation. In thoseinstances, the patient should be positioned to produce aview comparable to the RAO 30 degree position. If thereis any doubt about the position of the heart, the patientshould receive a small dose (eg 37 MBq) of radiopharma-ceutical and positioning optimized using the persistencemode of the computer.

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CLINICAL PRACTICES


Data AcquisitionSet camera pulse height analyzer for Tc-99m with a 30%window.

Set computer disk acquisition for a preset time of 100millseconds/frame in hexant (64x64) format for a totalof 600 frames (60 seconds) in byte mode.

Start computer 1-2 seconds prior to injection.

CommentsAfter acquisition is completed, the computer will say:“RECONFIGURATION DATA SET”; only after this iscompleted can the data be reviewed.

Stress Testing and Cardiac Emergencies

Computational AnalysisPerform a DSID to review the data, determine theadequacy of the bolus visually, and select the frames foraddition to set regions. On completion of this prelimi-nary review, use the Read+. command to add therequired frames to identify the superior vena-cava, rightatrium and ventricle, left ventricle and lungs.

Separate regions should be set over each of these areas,and the respective time-activity curves generated.

If the full-width-half maximum count density curve fromthe superior vena cava exceeds 3 seconds, the bolus ispoor and the study will have to be repeated.

The study is positive for a shunt if the pulmonary curvesshow a second peak at the time of filling of the leftventricle. A second peak is often seen in the rightventricular curve, due to overlap of the right and leftventricles in the RAO 30 degree position.

General Considerations

Proper preparations and careful precautions areessential for the production of the highest qualityelectrocardiographic monitoring and for the preventionof untoward complications.

Careful consideration of indications and contraindicationsof testing is essential. The purpose of a stress test inany given patient should be clear. The supervisor of thetest must be fully familiar with the entire procedure aswell as with the interpretation of the test.

Cardiopulmonary resuscitation equipment including adefibrillator and commonly used emergency cardiac drugsare essential and must be readily available.

Medical as well as paramedical personnel working in theexercise laboratory should be capable of providingcardiopulmonary resuscitation.

Before the stress test is performed, an informedconsent form should be obtained.

Patient PreparationPatients should be instructed to come to the stresslaboratory either after an overnight fast or at least fourhours after a light meal. They should be dressedcomfortably with lightweight shoes and the exerciselaboratory should be kept at a comfortable temperatureranging from 68 - 74oF with 40-60% humidity.

A careful history should be obtained and a brief physicalexamination should be performed, focusing on thecardiopulmonary system.

The supervisor of the test must evaluate its purpose andcarefully consider indications and contraindications totesting. A careful search much be made for factors whichmay produce false positive or false negative ECGresponses.

The entire testing procedure should be explained to thepatient in detail. This may include a brief demonstrationof actually walking on the treadmill. The patient shouldbe instructed to immediately report unusual orsignificant symptoms, e.g. chest pain, dizziness,

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lightheadedness, etc. The patient may request thetermination of exercise prematurely whenever necessary.

After the signing of informed consent, the skin must beprepared properly. The superficial keratinized layer ofepidermis should be removed by gentle skin abrasion witha dental burr, emery board, fine-grain sand paper, orvigorous rubbing with gauze. This should be washed awayby light cleansing with alcohol or other organic solvents.This eliminates excessive lipid content. Excessivelyvigorous debridement should be avoided in order toprevent edema formation and an increase in electricalresistance at the electrode-skin interface.

A 12-lead system, modified for use in the exercisingpatient, is then applied. Resting 12-lead electrocardio-grams are then obtained in the supine and standingpositions. Following this a 12-lead electrocardiogram isobtained with 30 seconds of hyperventilation.

Indications for Stress Testing

Diagnosis of ischemia.

Evaluation of the extent and location of ischemia.

Angiographic correlation.

Evaluation of the efficacy of medical therapy.

Follow up of CABG or PTCA.

Evaluation of prognosis in patients with recent orremote myocardial infarction.

Pre-op for non-cardiac surgery.

Assess for arrhythmia.

Evaluation of functional capacity.

Establishment of a baseline prior to beginning anexercise program.

Screening of patients with cardiac risk factors orthose involved in high-risk activities or occupations,e.g. airline pilots.

Contraindicationsto

Stress Testing

Absolute

Acute myocardial infarction.

Unstable or crescendo angina.

Serious cardiac arrhythmias (ventricular tachycar-dia, advanced or complete AV block).

Acute cardiac illnesses such as myocarditis,pericarditis, endocarditis or rheumatic fever.

Critical aortic stenosis.

Acute or severe congestive heart failure.

Marked arterial hypertension (BP>180/100).

Acute pulmonary embolism or infarction.

Any acute, serious, or uncontrolled non-cardiacdisorder.

Inability to give informed consent.

Protocols for Stress Testing

Bruce Protocol

Stage Speed Grade Duration (mph) (%) (min)

1 1.7 10 3 2 2.5 12 3 3 3.4 14 3 4 4.2 16 3 5 5.0 18 3 6 5.5 20 3 7 6.0 22 3

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1 1.7 0 3 2 1.7 5 3 3 1.7 10 3 4 2.5 12 3 5 3.4 14 3 6 4.2 16 3 7 5.0 18 3 8 5.5 20 3 9 6.0 22 3

Modified Bruce Protocol MGH Modified Bruce


1 1.7 0 3 2 1.7 10 3 3 2.5 12 3 4 3.4 14 3 5 4.2 16 3 6 5.5 20 3

Dipyridamole-ThalliumTc-99m-MIBI Test Protocol

0-4 min Dipyridamole infusion of 0.56 mg/kgover 4 min.

4-6 min Recline.

6-11 min Low level treadmill exercise,or arm weights, if able.

Isotope is injected at 10:00 inpatients who complete the exerciseprotocol, or in those unable toexercise.

In patients who are able to exercise,but unable to complete the exerciseprotocol, thallium is injected oneminute prior to the terminationof exercise.

50-100 mg Aminophylline are injectedIV after completion of the initialanterior image, of earlier if symptomswarrant.

Dobutamine-Test Protocol

Stage Dose Duration (min)

1 10 mcg/kg/min 3 2 20 mcg/kg/min 3 3 30 mcg/kg/min 3 4 40 mcg/kg/min 3

Patients are studied in the supine position; no exerciseis performed.

Isotope (Tl-201 to Tc-99m-MIBI) is injected at 11:00 ofthe protocol, or earlier if limiting symptoms develop.

Atropine 0.25 - 0.5 mg IV may be given at the discretionof the test supervisor if the heart rate response toDobutamine is well below 85% predicted maximum.

Maximum dose = 2.0 mg

Metoprolol 2.5-10.0 mg may be given IV to reverseDobutamine-related side-effects or ischemic ECGchanges.

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Adenosine Stress Test

The patient walks on the treadmill at 0% grade at0.5 - 1.7 MPH depending on physical condition.

As soon as the patient begins walking and it is clear he/she can maintain the selected pace begin adenosine in-fusion (140 ug/Kg/min) using IV infusion pump.

At 2 minutes of adenosine infusion inject tracer and con-tinue infusion for 3 additional minutes provided no ad-verse effects occur.

Discontinue adenosine after the 5th minute of infusionbut continue to have the patient walk for 1-2 additionalminutes after adenosine has been turned off.

Exceptions/Special Cases

Patients who have had a stent placed within 8 weeks ofthe test may walk on the treadmill at 1.0 - 1.5 MPH and0% grade. If the patient cannot walk then arm weightsmay be used instead.

Elderly (> 80 y-o) or any severely debilitated patientwho cannot walk or use arm weights and who may be athigher risk for high grade heart block with adenosineshould be considered for dipyridamole instead.

Endpoints at which to TerminateStress Testing

Absolute IndicationsPatient request.Significant, reproducible reduction of blood pressure and/or heart rate during increasing work loads.Significant symptoms or signs: severe chest pain, ataxia,vertigo, visual or gait disturbances.Serious arrhythmias: new ventricular tachycardia,ventricular fibrillation.Acute myocardial infarction or transmural ischemia.Malfunctioning equipment, e.g. treadmill, ECG monitor,etc.Marked hypertension (systolic blood pressure > 220mmHg or diastolic pressure > 110).

Urgent (i.e. Relative) IndicationsLess serious symptoms: significant chest pain, dizziness,marked fatigue or dyspnea.Leg cramps or claudication.Marked (2 mm or more) horizontal or down-sloping STsegment depression or marked (2 mm or more) STsegment elevation.Frequent or multifocal PVCs and persisting supraven-tricular tachyarrhythmias.

Criteria for Positive ECG Response to Stress

> 1mm of horizontal or down-sloping ST segmentdepression.

Upsloping ST segment depression > 2 mm beyond 0.08seconds from the J point.

Ancillary Signs of Stress-Induced IschemiaExercise-induced hypotension.Inverted U waves.Ventricular tachycardia provoked by mild exercise.Exercise-induced typical angina.Increased R wave amplitude(?).New third or fourth heart sound or heart murmurimmediately after exercise.

Factors which May Cause False PositiveStress ECG Responses

Drugs: digitalis, diuretics, antidepressants, sedatives,estrogen.Electrolyte imbalance: hypokalemia.Pre-existing ECG abnormalities: non specific ST-Tchanges, left ventricular hypertrophy, left bundle branchblock, right ventricular hypertrophy, right bundle branchblock (right precordial leads), Wolf-Parkinson-Whitesyndrome.Cardiac disorders: mitral valve prolapse syndrome, Wolf-Parkinson White Syndrome, cardiomyopathy, myocardi-tis, pericarditis, hypertensive heart disease, rheumaticheart disease.Miscellaneous: female gender, hyperventilation, food-glucose intake, pectus excavatum.

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Factors which May Cause False NegativeStress ECG Responses1

Drugs: antianginals, procainamide, quinidine,phenothiazines.

Inadequate exercise or heart rate response (less than 85%predicted maximum).

Improper lead system.

Single-vessel coronary artery disease.

Miscellaneous: left axis deviation, left anterior hemiblock.


Management of Complications During Stress Testing

General Statement

For the safety of patients, we have developed thefollowing guidelines in the event of clinical instability.

The condition will be discussed with the referringphysician and if necessary, patients will be sent to theEmergency Room after initial stabilization, or emergentlyas appropriate.

1 Chang, E.K. Exercise Electrocardiography - PracticalApproach, Williams and Wilkins, 1983.

(SBP>220 mmHG, or DBP>110 after treatment.)

Other medical conditions that a staff physician feels thatit is unsafe to send the patient home: (e.g.: Acute asthma,psychosis, seizure).

Arrhythmia and AV ConductionAbnormality

High degree of malignant arrhythmia that is diagnosedby stress test.Pacemaker malfunction or AICD malfunction during stresstest.New onset of high degree A-V block.New onset of arrhythmia: Atrial fibrillation, atrial flutter,supra ventricular tachycardia, junctional rhythm, brady-cardia or tachycardia that persist.Cardiac arrest.....Follow ACLS guidelines.

A copy of specific ACLS guidelines for treatment ofthe above conditions is located in the work area of thestress lab.

Non Arrhythmia Ischemia, LV Failure, or Other Medical

Problems

ECG and/or clinical evidence of evolving severe ischemiaor acute myocardial infarction despite appropriatetherapy.

Congestive heart failure not responding to initialtreatment.

Hypotension that is not responsive to the initialtreatment.

Markedly positive stress test and a staff physician feelsthat it is unsafe to send the patient home.Extreme hypertension that is not responding to initialtreatment.

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