The Ogilvie syndrome (colonic pseudo-obstruction) is best distinguished from mechanical large bowel obstruction by which finding?
- A No transition point on CT, with gas extending into the rectum ✓
- B Gross distension of the cecum exceeding 12 cm on plain radiograph
- C Air-fluid levels in the small bowel on erect plain radiograph
- D Absence of peristaltic sounds on clinical examination
Correct answer: A. No transition point on CT, with gas extending into the rectum
Explanation
Ogilvie syndrome (acute colonic pseudo-obstruction) is characterized on CT by massive colonic dilatation without a mechanical obstructing lesion — crucially, gas is present throughout the colon including the rectum and sigmoid, with no transition point. In mechanical large bowel obstruction, a distinct transition point (collapsed colon distal to the obstruction) is identified. Cecal dilatation >12 cm is the threshold for risk of perforation in Ogilvie syndrome but also occurs in mechanical obstruction. Absent bowel sounds occur in both.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.