Ileus

Preliminary Diagnosis: Ileus

I. What imaging technique is first-line for this diagnosis?

• Plain abdominal radiography

II. Describe the advantages and disadvantages of this technique for diagnosis of an ileus.

Advantages

• Quick, efficient, and cost-effective modality to evaluate for an ileus

• Uses less ionizing radiation than CT imaging and fluoroscopy

Disadvantages

• May not be able to localize a primary abdominal or pelvic inflammatory or infectious process that causes a secondary ileus

III. What are the contraindications for the first-line imaging technique?

• No significant contraindications to plain radiography exist.

IV. What alternative imaging techniques are available?

• Nonenhanced CT

• Fluoroscopy

• Upper GI examination

• Contrast enema

V. Describe the advantages and disadvantages of the alternative techniques for diagnosis of an ileus.

CT without contrast

Advantages

• May help evaluate for a partial obstruction and localize a transition point where the differential includes a dynamic ileus versus partial bowel obstruction

• May localize a primary abdominal or pelvic inflammatory process that may elicit a secondary dynamic ileus so that the primary process may be treated

Disadvantages

• Exposes the patient to much more ionizing radiation when compared to plain radiography

• Patients susceptible to more motion artifact as CT imaging scan times are longer than plain radiography

Fluoroscopy

Advantages

• Able to evaluate for a mechanical obstructing upper gastrointestinal lesion as contrast propagates distally

Disadvantages

• Exposes the patient to more ionizing radiation than plain radiography

Upper GI examination

Advantages

• Ingestion of oral contrast is patient dependent and may be time-consuming in noncooperative patients.

Disadvantages

• A normal upper GI examination may not rule out a distal bowel obstruction.

Contrast enema

Advantages

• Contrast enema may be therapeutic and stimulate bowel peristalsis.

• Normal contrast enema may rule out colonic mechanical obstruction.

Disadvantages

• Normal contrast enema may not rule out upper GI obstruction.

• Contrast enema examinations are painful and irritating as the contrast causes colonic distention.

VI. What are the contraindications for the alternative imaging techniques?

CT without contrast

• Contraindicated in pregnant patients, especially within the first two trimesters

Fluoroscopy

• Contraindicated in pregnant patients, especially within the first two trimesters

Upper GI examination

• Upper GI and contrast enema examination are contraindicated in patients with esophageal, stomach, or bowel perforation and associated free air

Contrast enema

• Contraindicated in patients with esophageal, stomach, or bowel perforation