Kyoung Moo Im
We report a case of acute-on-chronic mesenteric ischemia (AOCMI) in an 85-year-old woman presenting with progressive postprandial abdominal pain, signs of panperitonitis, and free intraperitoneal air. Emergency laparotomy revealed diffuse small bowel ischemia without clear demarcation, reflecting acute ischemia superimposed on chronic hypoperfusion. Intraoperative indocyanine green (ICG) fluorescence angiography enabled selective resection of nonviable bowel, preserving potentially salvageable intestine. Delayed recognition of a nine-month history of chronic mesenteric ischemia (CMI) prompted staged endovascular revascularization of the superior mesenteric artery (SMA). Despite transient short bowel syndrome (SBS) requiring parenteral nutrition, bowel continuity was ultimately restored. This case highlights the diagnostic challenge of AOCMI and demonstrates that selective bowel salvage combined with staged multidisciplinary intervention can preserve bowel function and quality of life even in elderly high-risk patients.