1. Diagnostic Procedures in Respiratory Disease

7/27/2019 1. Diagnostic Procedures in Respiratory Disease

1/41

Diagnostic Procedures inRespiratory Disease


2/41

Routine Radiography

The standard chest examination consists of a PA

(posterioranterior) and lateral chest x-rayUsed for evaluation of the pulmonary

parenchyma, the pleura, the airways and the

mediastinum

Lateral decubitus position => assess the volumeof pleural effusion and demonstrate whether a

pleural effusion is mobile or loculated


3/41

Portable Radiography

Used for acutely ill patients who cannot be transported or

cannot stand for PA and lateral views

Portable films are more difficult to interpret because of

several limitation:

1) the single AP projection

2) variability in over- and underexposure of film

3) a shorter focal spot-film distance leading to lack of edge

sharpness, and loss of fine detail

4) magnification of the cardiac silhouette and other anterior

structures by the AP projection


4/41

Chest Radiography

Normal PA Chest X-ray Normal Lateral Chest X-ray


5/41


6/41

Radiographic Patterns

Patient with severe emphysema. Chestradiograph shows hyperexpansion

of both lungs with bullous changes at the

right lung base and leftward mediastinal

shift.


7/41


Patient with hydrostatic

pulmonary edema due to left-sided heart failure. Chest frontal

radiograph demonstrates classic

batwing distribution of

pulmonary edema


8/41


Multifocal pulmonary opacities

Bilateral large and small pulmonary

nodules and masses due to metastatic

tumor


9/41


Basilar pneumothorax with visible pleural

reflection (red arrows)

Subcutaneous emphysema (yellow arrow).


10/41


Right upper lobe pneumonia Bilateral pleural effusion


11/41


The red arrows indicate the edge of

the collapsed right lung. Their is

also significant shift of the

mediastinum to the left


12/41

Computed Tomography

CT is particularly valuable in:

assessing hilar and mediastinal (valuableespecially in the staging of lung cancer)

identifying and characterizing the chest wall andspine disease

identifying areas of fat density or calcification inpulmonary nodules

distinguish vascular from nonvascular structures(particularly lymph nodes and masses fromvascular disorders) by using of contrast material


13/41

High-resolution CT (HRCT)

In HRCT the thickness of cross-sectional

images is ~ 1-2 mm, narrower than the usual7-10 mm in conventional CT

Used for diagnosis and the assessment of

interstitial lung disease such as lymphangitic

carcinoma, idiopathic pulmonary fibrosis,sarcoidosis, and eosinophilic granuloma and

other generalized lung diseases such as

emphysema , bronchiectasis
http://en.wikipedia.org/wiki/Interstitial_lung_diseasehttp://en.wikipedia.org/wiki/Interstitial_lung_disease


14/41

Multidetector CT

(MDCT 2 to 64 detectors)

Multiple slices in a single rotation and in a shorter period

of time = > increased image reconstruction ability

Shorter breath holds is beneficial for all patientsespecially for children ,the elderly and the critically ill

Improved imaging of the pulmonary vasculature and the

ability to detect segmental and subsegmental emboli

CT pulmonary angiography is the test of choice in theevaluation of pulmonary embolism


15/41

Magnetic Resonance Imaging

MR is less used than CT in the evaluation of the respiratory systemdisease because of several disadvantages:

poorer spatial resolution and less detail of the pulmonary parenchymaimages difficult to obtain in patients who cannot lie on their backs or

cannot hold their breaths as a require to get good MR images

Contraindications: - unstable and/or ventilated patients

- presence of metallic foreign bodies, pacemakersand intracranial aneurysm clips

MR is well suited to distinguish vascular from nonvascular structureswithout the need for contrast

MR is useful in the assessment of vascular abnormalities (pulmonaryemboli, aortic aneurysms or dissection) when radiation and IV contrastmedium cannot be usedGadolinium can be used as an intravascular contrast agent for MR

angiography


16/41

Nuclear Medicine Techniques

Nuclear imaging is based on the selective uptake ofvarious compounds by organs of the body

Radioactive isotopes can be administered by IV orinhaled routes, or both. The most commonly usedradionuclides are: technetium-99m (intravenous) andXenon-133 (gaseous)radiolabeled xenon gas inhalation is used to

demonstrate the distribution of ventilationVentilation-perfusion lung scanning is used for theevaluation of patients with impaired lung function whoare being considered for lung resection and those withpulmonary embolism


17/41

Positron Emission Tomographic (PET)

Scanning

Used to identify malignant lung lesions based

on their increased uptake and metabolism ofglucose

The technique involves injection of F-fluoro-2-

deoxyglucose (FDG) which is taken up by

metabolically active malignant cellsUsed in the evaluation of solitary pulmonary

nodules and in staging lung cancer


18/41

Positron Emission Tomographic (PET)

Scanning

The hybrid PET/CT scans provide images that helppinpoint the abnormal metabolic activity to anatomical

structures seen on CT

more accurate diagnoses thanthe two scans performed separatelyFDG-PET can differentiate benign from malignant

lesions as small as 1 cmFalse-negative findings: low metabolic activity lesions

(carcinoid tumors, bronchioloalveolar cell carcinomas) orlesions< 1cmFalse-positive findings: due to FDG uptake in

inflammatory conditions (pneumonia and granulomatousdiseases)


19/41

Whole body PET CT

coronal images show

abnormal focal FDGuptake in right lung mass

lesion - Primary Ca lung

(First image is contrast-

enhanced CT, next is

corresponding PET slice

and third is fused PET CT)


20/41

Pulmonary Angiography

Visualization of pulmonary arterial system after

injection of a radiopaque contrast medium through a

catheter placed in the pulmonary artery

Indications:

pulmonary embolism (most common)

pulmonary arteriovenous malformation

pulmonary arterial invasion by a neoplasm


21/41

Ultrasound

US produces images using reflection of the ultrasound beamfrom interfaces between tissues with differing acoustic

properties US involves no exposure to X-ray or magnetic waves, which

it makes safe to use in pregnant patients and patients withimplanted medical devices

Used for:

detection of pleural abnormalities guiding percutaneous needle biopsy of peripheral lung,

pleural or chest wall lesions

identifying septations within loculated collections

placement of a needle for sampling of pleural liquid


22/41

Collection of Sputum

Sputum can be collected by spontaneous

expectoration or by sputum induct ion(after

inhalation of an irritating aerosol such as

hypertonic saline)

Sputum can be processed for:

staining and culture for routine bacterialpathogens, mycobacteria, fungi, viruses,

Pneumocystis jiroveci

cytologic staining for malignant cells


23/41

Percutaneous Needle Aspiration

(Transthoracic)

Can be used to aspirate material from a

pulmonary lesion through a needle inserted

through the chest wall

Used to obtain a diagnosis or to decompress or

drain a fluid collection

Usually performed under CT or US guidanceSampling error due to the small size of the tissue

sample is a disadvantages of the technique


24/41

Thoracentesis

Is an invasive

procedure to removefluid orairfrom the

pleural space for

diagnostic or

therapeutic

purposes(palliation ofdyspnea)

Performed by blind

needle aspiration or

by US guidance
http://en.wikipedia.org/wiki/Pleural_effusionhttp://en.wikipedia.org/wiki/Pneumothoraxhttp://en.wikipedia.org/wiki/Pleural_cavityhttp://en.wikipedia.org/wiki/Pleural_cavityhttp://en.wikipedia.org/wiki/Pneumothoraxhttp://en.wikipedia.org/wiki/Pleural_effusion


25/41

Thoracentesis

Analysis the pleural fluid to determine the cause

and to determinewhether the effusion is atransudate or an exudate

pleural fluid glucose,

amylase

Lactate dehydrogenase


26/41

Transudative or exudative pleural

effusions ?

Exudativepleural effusions meet at least one of thefollowing criteria :

1. Pleural fluid protein/serum protein >0.5

2. Pleural fluid LDH/serum LDH >0.6

3. Pleural fluid LDH more than two-thirds normal upper limitfor serum

transudative pleural effusions meet none


27/41

Transudative Pleural Effusions:

Congestive heart failure

Cirrhosis

Pulmonary embolization

Nephrotic syndrome

Peritoneal dialysis

Superior vena cava obstruction

Myxedema

Urinothorax


28/41

Exudative Pleural Effusions:

Neoplastic diseases

Infectious diseases

Pulmonary embolization

Gastrointestinal disease

Collagen vascular diseases

Post-coronary artery bypass surgery

Asbestos exposure

Sarcoidosis

Meigs' syndrome Drug-induced pleural disease

Radiation therapy

Hemothorax

Iatrogenic injury

Pericardial disease


29/41

Bronchoscopy

direct visualization of the tracheobronchial tree

I. flexible fiberoptic bonchoscopy

II. rigid bronchoscopy


30/41

I. Flexible Fiberoptic Bronchoscopy

Usually performed in an awake but sedated patientThe bronchoscope is passed through the mouth or the

nose , between the vocal cords and into trachea andpermit to visualize virtually all airways to the level ofsubsegmental bronchiUsed to identify endobronchial pathology (tumors,

granulomas, bronchitis, foreign bodies and sites ofbleeding)

To take samples from airway lesions by specificmethods including washing, brushing, and biopsy

To take samples from the distal pulmonaryparenchyma (bronchoalveolar lavage, transbronchialbiopsy)


31/41

II. Rigid Bronchoscopy

Performed in an operating room on a patient

under general anesthesia

Rarely used, in some situations (the retrieval

of a foreign body and the suctioning of a

massive hemorrhage) because of a largersuction channel


32/41

Transbronchial Needle Aspiration

TBNA is a minimally invasive procedure that

provides a nonsurgical means to diagnose and

stage bronchogenic carcinoma by sampling the

mediastinal lymph nodes

allows also sampling of peripheral, submucosal,

and endobronchial lesions involves use of a needle passed through the

bronchoscope for sampling of tissue through the

trachea or bronchial wall


33/41


34/41

Transthoracic needle aspiration and

biopsy

Transthoracic needle aspiration and biopsy(TTNA/B) is a safe rapid method used to

achieve definitive diagnosis for most thoracic

lesions, whether the lesion is located in the

pleura, the lung parenchyma, or themediastinum


35/41

Autofluorescence Bronchoscopy

(AFB) uses bronchoscopes with an additional lightsource that allows distinguish between normal and

abnormal tissue

Used for screening of premalignant lesions(airway dysplasia) and carcinoma in situ among

high-risk patients


36/41

Medical Thoracoscopy/Pleuroscopy

A minimally invasive procedure that allows access

to the pleural space using a combination of

viewing and working instruments

Used fordiagnostic (evaluation of a pleural

effusion or biopsy of presumed parietal pleural

carcinomatosis) and therapeutic procedures(pleurodesis for prevent recurrent pleural effusion

or pneumothorax)


37/41

Therapeutic Bronchoscopy

Therapeutic bronchoscopy includes removalof foreign body, control of active bleeding

(hemoptysis) management of benign airway

stenosis, laser bronchoscopy, cryotherapy,

endobronchial brachytherapy, photodynamictherapy and airway stents


38/41

Mediastinoscopy and Mediastinotomy

Surgical procedures used to examine andsampling mediastinal masses and lymph nodes

Mediastinoscopy via a suprasternal incisionprovides access to mediastinal masses andlymph node levels 2R, 2L, 3, 4R, 4L

Mediastinotomy (the Chamberlain procedure)

via a parasternal incision allows access to thestation 5 and 6 lymph nodes

An alternative to surgery procedures is thecombination of EUSFNA and EBUSFNA


39/41

Video-assisted thoracoscopic surgery

(VATS)

VATS is a keyhole surgical procedure in the

operating room, under general anesthesia with

one-lung ventilation using disposable instruments,

generally for therapeutic purpose

Used to biopsy lesions of the pleura, peripherallung tissue or to remove peripheral nodules for

both diagnostic and therapeutic purposes


40/41

Indications for video-assistedthoracoscopic surgery (VATS)

General intrathoracic cavity

Diagnosis or biopsy of any intrathoracic structure

Laser application for treatment of tumors

Diagnosis and drainage of pleural effusions

Treat chylothorax

Lungs

Wedge resection, segmentectomy, lobectomy

Closure of persistent/recurrent pneumothorax

Identification of broncho-pleural fistula

Pleura

Lysis of adhesions

Pleurodesis

Mediastinum

Removal of mediastinal cysts

Thymectomy

Resection of posterior mediastinal neurogenic tumors


41/41

Thoracotomy

Now is frequently replaced by VATS

Can be used to biopsy and/or excise lesionsthat are too deep or too close to vital structuresfor removal by VATS

The choice between VATS and thoracotomyneeds to be made on a case-by-case basis

Documents

1. Diagnostic Procedures in Respiratory Disease