Evaluation of Superior Mesenteric Artery Syndrome and Related Anatomy by MDCTA

[Objective] To study the influence of the third portion of the duodenum by the angle and distance of superior mesenteric artery(SMA) and abdominal aorta(AA) using MDCTA in normal and superior mesenteric artery syndrome(SMAS).[Materials and Methods] The angle and the distance of SMA and AA between them at the third portion of the duodenum of 108 normal person and 17 patients with SMAS syndrome were studied and compared.[Results] In each SMAS patient,MDCT demonstrated gastric and proximal duodenal dilatation with abrupt narrowing of the third portion of the duodenum between the aorta and SMA.of 108 normal person and 17 patients with SMAS,the mean angle of SMA and AA was 46.3° ±16.5° and 14.3° ±5.6°.The mean distance between SMA and AA at the third portion of the duodenum between the aorta and SMA was 14.7 ± 4.4mm and 4.5 ± 0.8mm respectively.[Conclusion] MDCTA enables direct visualization of obstructed bowel owing to duodenal compression by the SMA and AA.MDCTA can be used to confirm the CT criteria of decreased aortomesenteric angle and distance in SMAS.