[Isolated spontaneous dissection of the superior mesenteric artery in two cases treated with conservative therapy].

We report two cases of isolated spontaneous dissection of the superior mesenteric artery (SMA). Both patients complained of abdominal pain with sudden onset and were given diagnoses of dissection of the SMA based on abdominal CT scanning. CT showed dissention of the SMA with thrombosis of the false lumen and narrowing of the true lumen. Therefore there were no symptoms of bowel ischemia, and after hospitalization both cases received conservative therapy with anticoagulation and antiplatelet therapy. Spontaneous dissection of the SMA without aortic dissection is very rare, and only 53 cases have been recorded in Japan.