A case of colovesical fistula associated with pelvic arteriovenous malformation.

Arteriovenous malformations (AVMs) are rare, especially in the pelvis. Colovesical fistulas (CVFs) occur when fistulas form between the intestine and bladder. The treatment for CVFs is generally intestinal resection and fistula resection between the colon and the bladder. However, in patients with pelvic AVMs, colectomies may increase the bleeding risk or exacerbate the AVMs due to vascular resection or blood flow changes. A 67-year-old man was diagnosed with an asymptomatic pelvic AVM during preoperative testing for a CVF associated with sigmoid diverticulitis. Laparoscopic sigmoid resection was performed for the CVF, and he recovered without complications. In bowel resections associated with CVFs complicated by asymptomatic pelvic AVMs, safe laparoscopic bowel resection is possible by preoperatively identifying the AVM's inflow and outflow vessels and evaluating their relationship to the resected bowel. Herein, we report a case where a laparoscopic sigmoidectomy was performed for a sigmoid CVF associated with an asymptomatic pelvic AVM.