Computed Tomography findings of Intersigmoid Hernia

Abstract Purpose To evaluate the computed tomography findings of intersigmoid hernias. Methods Between April 2010 and March 2018, seven patients who were surgically diagnosed with intersigmoid hernia from three institutions were enrolled in this study. Two radiologists evaluated imaging findings for the herniated small bowel, the distance between the occlusion point and bifurcation of the left common iliac artery, and its relationships with the surrounding structures. Results All patients were male ,and their mean age (standard deviation, range) was 61.0 (13.5, 36–85) years. The mean size of the bowel loops was 5.19 (1.34, 4.0-8.3) cm in the caudal direction, 3.59 (0.79, 2.5–5.1) cm in the lateral, and 3.43 (0.64, 2.5–4.7) cm in the anterior-posterior direction, 37.88 (27.79, 15.6–103.0) cm3 calculated by the length. The obstruction point was located 3.57 (0.59, 2.84–4.70) cm inferior to the bifurcation of the left common iliac artery. In all cases, the small bowel ran under the point that the inferior mesenteric vessels bifurcated to the superior rectal vessels and the sigmoid vessels and formed a sac-like appearance between the left psoas muscle and the sigmoid colon. The ureter ran dorsal to the point of the bowel stenosis, and the left gonadal vein outside the small bowel loops. Conclusion In all cases, the small bowel ran under the position of the inferior mesenteric vessel's bifurcation and became strangulated at the anterior of the left ureter, showing a sac-like appearance medial to the left gonadal vein. These findings may be characteristic of the intersigmoid hernia.