Large Bowel Internal Hernia Secondary to Reimplanted Ureter

Internal hernias are difficult to diagnose clinically, and normal cross-sectional imaging has been documented in many patients. Transmesenteric hernias from congenital defects or prior abdominal surgery are most common. A 46-year-old previously healthy female presented to the emergency department with acute onset nausea and vomiting eight years after a right ureteral transection during a laparoscopic hysterectomy, with a delayed ureterolysis and reimplantation into the bladder. Rectal contrast CT scan demonstrated a partial large bowel obstruction that was unclear if it was due to an underlying mass, stricture, or internal herniation. The patient was taken for exploratory laparotomy which demonstrated redundant transverse colon herniated under the mobile right ureter; an extended right hemicolectomy was performed. This report describes alteration of retroperitoneal anatomy creating a potential space for colonic herniation and emphasizes that clinical suspicion must remain high for patients presenting with obstructive or partially obstructive symptoms.