ROSH Gastrointestinal Practice Exam

Which diagnostic modality is typically used for evaluating suspected bowel obstruction?

1. MRI

2. Ultrasound

3. CT scan

4. X-ray

The correct answer is: CT scan

The CT scan is considered the gold standard for evaluating suspected bowel obstruction due to its high sensitivity and specificity. It provides detailed cross-sectional images of the abdomen, allowing clinicians to visualize the intestines, identify the site of blockage, and assess any associated complications such as perforation or infarction. CT scans can also help in determining the extent of the obstruction and any underlying causes, such as tumors or adhesions, which is critical for guiding management. Other options, while useful in certain contexts, are generally less effective for this specific indication. For instance, MRI is not commonly used for bowel obstruction evaluation due to the time required for the scan and the challenges associated with imaging moving organs. Ultrasound can be useful, especially in pediatric populations or during pregnancy, but it has limitations in assessing the entire bowel and may not provide sufficient detail in adult cases. X-rays can identify air-fluid levels and general bowel distention but lack the detailed diagnostic capability that a CT scan offers, often leading to missed diagnosis or inadequate information on the cause of obstruction.