Noncalcified Gallstone Ileus in Computed Tomography (CT) Abdomen and Pelvis With Contrast.

Gallstone ileus is a rare but serious complication of chronic cholecystitis, causing mechanical small bowel obstruction. Contrast-enhanced computed tomography (CT) plays a key role in radiological diagnosis. The classic findings are known as Rigler's triad, comprised of pneumobilia, small bowel obstruction, and calcified gallstones. We report a unique case of a 74-year-old female patient who presented with hallmark clinical features of bowel obstruction. CT revealed bowel obstruction and pneumobilia but did not show calcified gallstones, deviating from the usual Rigler's triad. Following midline laparotomy, a noncalcified gallstone was confirmed causing bowel obstruction. This case underscores the need to consider gallstone ileus in small bowel obstruction even in rare cases where conventional CT findings are not present, alongside the value of comprehensive radiological analysis and maintaining a high degree of clinical suspicion. Timely recognition of such atypical cases is vital for effective surgical treatment and better patient outcomes.