Foramen of Winslow/lesser sac internal hernia containing cecum and terminal ileum

Case Discussion

Uncommon case of foramen of Winslow hernia containing a hypermobile cecum and terminal ileum. The foramen of Winslow is a normal anatomic structure separating the peritoneal cavity from the lesser sac and results from rotation of the upper abdominal viscera during fetal development. 

This is a case that requires careful attention and following of the bowel into and out of the internal hernia to understand which segments are involved. The distal ileum can be followed into the lesser sac to the TI/IC valve and cecum, which fills much of the upper abdomen and gastric curvature. The ascending colon can be followed from the inverted and displaced cecum out of the hernia and into the pelvis along the colon's redundant and elongated course. Notice how stretched the main portal vein is, which has diminished flow. 

The operative note details..."the cecum was noted to be absent from the right lower quadrant. The terminal ileum was followed cephalad to its entry through the foramen of Winslow. The transverse colon was very redundant with the midtransverse colon in the pelvis. With gentle traction in the terminal ileum and transverse colon, the appendix came into view. The mesoappendix was grapsed and pulled toward the RLQ, and there was sudden reduction of the entire right colon and terminal ileum, including a very dilated but viable cecum. A cecopexy was performed..."