Spontaneous dissecting aneurysm of the main trunk of the superior mesenteric artery: report of a case.

A 47-year-old man with a sudden onset of abdominal pain was diagnosed as having an aneurysm of the main trunk of the superior mesenteric artery (SMA), which induced ischemic colitis of the transverse colon probably because of a transient decrease in the SMA blood flow. The patient was successfully treated by resection of the aneurysm and an end-to-side anastomosis of the SMA to the aorta. A histological examination revealed a spontaneous dissecting aneurysm of the SMA.