CT Enterography & Multiphase CT,

Do I Need these Exams for

Abdominal Pain?

Kristen Bishop, MD

Assistant Professor

UTSW Dept. of Radiology

February 14, 2015

The most appropriate modality to work up

a patient with abdominal pain is:

A. X-ray

B. Ultrasound

C. CT

D. MRI

E. Depends on additional

details in the H&P

A. B. C. D. E.

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Computed Tomography

Godfrey Hounsfield – British

electrical engineer

Inventor of computed

tomography

Image an object in axial slices

Contrast Agents - Background

Coating radiolucent

structures with a metallic

powders or pastes made the

surface radio-opaque

1910 – barium sulfate first

used for GI imaging

Water soluble contrast agents

Iodine opaque to x-rays

1928 – First urographic

iodinated contrast agent

1968 - first nonionic agent

was developed

Some agents FDA approved

for oral use

Example of CT without and with contrast

The Multiple Phase Exam (Liver Tumor Protocol)

CT Urography

CT Enterography

CT Protocol Variables

IV contrast necessary?

–Some scans do not require

–Contraindications to contrast

If IV contrast necessary

–Number of postcontrast phases and timing for each phase

–Radiology selects a protocol based on provided clinical history

Use of oral contrast and type

–Standard barium, Volumen (CT enterography), or water soluble

Portions of anatomy scanned or excluded

–Abdomen vs. pelvis

Is CT even the best exam for the clinical question?

74176 CT, abdomen and pelvis; without contrast material

74177 CT, abdomen and pelvis; with contrast material

74178 CT, abdomen and pelvis; without contrast material, followed by contrast material(s) and further sections

74150 CT, abdomen; without contrast material

74160 CT, abdomen; with contrast material

74170 CT, abdomen; without contrast material, followed by contrast material(s) and further sections

72192 CT, pelvis; without contrast material

72193 CT, pelvis; with contrast material

72194 CT, pelvis; without contrast material, followed by contrast material(s) and further sections

74174 CT angiography, abdomen and pelvis, with contrast material(s), including noncontrast images, if performed, and image postprocessing

74175 CT angiography, abdomen, with contrast material(s), including noncontrast images, if performed, and image postprocessing

72191 CT angiography, pelvis, with contrast material(s), including noncontrast images, if performed, and image postprocessing

74261 CT colongraphy, diagnostic including image postprocessing; without contrast material

74262 CT colongraphy, diagnostic including image postprocessing; with contrast material

74263 CT colongraphy, screening including image postprocessing

CPT Codes

CMS Measure (for outpatients)

CMS Measure

(Abdominal CT Scans without and with

contrast)

But is CT without and with contrast ever indicated?

Yes! Exclusions from the CMS measure include ICD-9 codes for:

–Blunt abdominal trauma

–Hematuria, bladder cancer, urinary infection

–Adrenal mass

–Jaundice, liver lesion, liver or biliary cancer

–Pancreatic mass, hypoglycemic workup, pancreatitis

–Among others

How do I know which study is most appropriate?

ACR Appropriateness Criteria

Imaging Appropriateness Topics

Breast

Cardiac

Gastrointestinal

Musculoskeletal

Neurologic

Pediatric

Thoracic

Urologic

Vascular

Women’s Imaging

Interventional

Radiation Oncology

For example, your patient has abdominal pain

But does he have:

–Fever and abdominal pain

(or suspected abscess)?

–Acute pancreatitis?

–Blunt abdominal trauma?

–Crohn’s disease?

–LLQ pain – suspected diverticulitis?

–RLQ pain – suspected appendicitis?

–Right upper quadrant pain?

–Suspected small bowel obstruction?

–Acute flank pain – suspicion for stone?

–Acute pyelonephritis?

Need to have targeted workup approach –

No “generalized abdominal pain” listed

Gastrointestinal

Urologic

Example scenario

35 year old female with fever, dysuria, and unilateral

flank pain

– CBC with elevated WBC

– UA with + bacteria, + WBC, + nitrite

– No significant PMH

Workup using ACR

Appropriateness Criteria

Acute pyelonephritis

– Uncomplicated patient

– Imaging not usually indicated

– Unless patient does not respond to therapy within

72 hours

Workup using ACR

Appropriateness Criteria

– Contrast with the “complicated patient”

– Diabetes

– Immunocompromised, history of stones

– Urologic history

– Not responding to therapy

– Most appropriate is CT abdomen and pelvis without

and with contrast

Example Scenario #2

35 year old male with long history of crampy abdominal

pain and diarrhea

– Lab studies demonstrate iron deficiency anemia

– Family history of Crohn’s disease

Workup using ACR

Appropriateness Criteria

Crohn’s disease

– First presentation in an adult

– CT enterography highly preferred

– MR enterography also can be considered

Workup using ACR

Appropriateness Criteria

–Other scenarios to consider

–Known Crohn’s with worsening symptoms

–Standard CT with contrast and CT enterography

equally good

–Known Crohn’s with mild symptoms or surveillance

–CT enterography best

–Children or young adults

–Consider MR enterography

Example Scenario #3

45 year old female with right upper quadrant pain after

eating

– Ultrasound demonstrates gallstones

– Also 2 cm echogenic lesion within the liver

– No history of liver disease or risk factors for liver

disease

– No known primary malignancy

Workup using ACR

Appropriateness Criteria

Liver lesion > 1 cm, incompletely characterized

– Patient with no liver disease or known malignancy

– MRI without and with contrast best study

– CT without and with contrast slightly less preferred

Workup using ACR

Appropriateness Criteria

– Other scenarios

–Patient with liver disease

– MRI without and with contrast best study

– CT without and with contrast less preferred

– Consider biopsy

–Patient with known primary malignancy

– MRI without and with contrast best study

– CT without and with contrast or CT with contrast slightly

less preferred

– Consider biopsy

Try it out!

ACR Appropriateness Criteria

http://www.acr.org/Quality-Safety/Appropriateness-Criteria

CT abdomen with and without intravenous

contrast is appropriate in which of the

following situations:

A. To evaluate a focal hepatic lesion

B. To evaluate a focal pancreatic

lesion

C. To evaluate a focal renal lesion

D. To evaluate a focal adrenal lesion

E. All of the above, but MRI may

sometimes be more appropriate

than CT A. B. C. D. E.

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What is the name of the website which can

be used to find the most appropriate

radiologic workup for a given condition?

A. ACR Practice Guidelines

B. ACR Consensus Statements

C. ACR White Paper on the

Management of Incidental

Findings

D. ACR Appropriateness Criteria

E. ACR Decision Making Criteria

A. B. C. D. E.

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