(077) A Proposed Urachus-Based Peritoneal Hinge-Flap for Repair of Genito-Urinary and Recto-Vesical, Urethral and Vaginal Fistulae in Men and Women

Abstract Introduction We developed a pedicled urachus-based peritoneal hinge-flap for gender-affirming salvage vaginoplasty (Smith and Garcia, Sex Med, 2022) and have found the technique simple and durable. We considered other uses for this versatile, well-vascularized pedicle flap, and found that this flap can be useful to cover the repair site for various lower urinary tract, rectal and vaginal fistulae, as well. The flap can be rotated on either side of the bladder, or between the bladder and rectum, or, on either side of vagina, to cover and reinforce a variety of common fistula repair sites. Objective Our objective was to describe the flap, its anatomic margins, and, report on our experience using it in 7 cases. Methods The flap contains three layers, each with an independent blood supply: peritoneum, urachus/medial umbilical ligaments, and Transversalis fascia. The flap is taken just lateral to the medial umbilical ligaments and can be elevated caudally as far as the posterior wall of the bladder, depending on the length needed. When harvested from the level of the umbilicus, 24 cm of flap length can be reliably achieved. Flap width (at mid-length) is 8-9 cm. Maximum caudal reach of the flap is to the level of 2-3 cm from the perineum. Results We have used this flap to cover 1 bladder diverticulum excision site (endoscopic circumferential excision Video provided), 4 colo-vesical repair sites (3 Robotic, 1 lap), and 2 vesico-vaginal fistulae (Robotic). In each case, the flap easily reached the repair site and was sutured into place, without detectable sequellae. We cover the repair site with the peritoneal surface of the flap. Conclusions As shown in Figure 1, the flap’s anatomic location and dissection is very familiar to urologist laparoscopic surgeons. The flap’s reliable blood supply, long available length, and ability to rotate the flap as desired, makes it a useful adjunct to complex repairs for urologists to consider. Disclosure No