1Department of Hepatology and Gastroenterology, Toho University Medical Center Omori Hospital, 2Department of Clinical Functional Physiology, Toho University Medical Center Omori Hospital, 3Department of General Medicine and Emergency Care, Toho University Medical Center Omori Hospital
The patient was a 65-year-old man who had experienced upper abdominal pain during a round of golf on the previous day and was admitted to the hospital. Although the intimal flap was not delineated on abdominal ultrasonography (US), we noted mild dilation in the proximal part of the superior mesenteric artery (SMA), and antegrade signals on the dorsal side and flapping retrograde signals on the ventral side were observed on color Doppler ultrasonography. Because abdominal multi-detector row CT (MDCT) revealed dissection at the root of the SMA and localized thickening of the jejunal wall, a diagnosis of isolated superior mesenteric artery dissection (ISMAD) complicated by jejunal ischemia was made and anticoagulation therapy was initiated. The hemodynamics of the dissected part of the SMA and ischemic jejunum was monitored by US and MDCT. Both the true and the false lumen of the dissected SMA showed blood flow to about 2 cm distally from the root, but progressive narrowing of the true lumen resulting from dilation of the false lumen was confirmed by follow-up US. The thickened part of the jejunal wall, in which the contrast was attenuated on MDCT and contrast-enhanced US (CEUS), showed improvement in blood flow by CEUS on the 19th hospital day. Thereafter, the patient stopped complaining about abdominal pain, and oral intake of meals resumed on the 26th hospital day. However, pain in the left flank appeared postprandially on the 38th hospital day. Since a narrowed part was noted in the jejunum on barium radiography of the small intestine, open surgery was carried out on the 59th hospital day. Because the jejunum was narrowed over 30 cm from a point 20 cm anally to the ligament of Treitz, this segment was resected and, based on histopathological examination of the resected specimen, a diagnosis of delayed stenosis associated with ischemia was made. US proved extremely useful in evaluating the state of dissection of the SMA and the viability of the intestine during conservative treatment.