(520) The Use of Gracilis Muscle Flap in Radial Forearm Free Flap Phalloplasty to Decrease Urethral Fistula Rate: Initial Outcome

Abstract

Abstract Introduction `- Chang and Hwang, in 1984, described the technique of Radial Forearm Free Flap Phalloplasty (RFFFP). It is now considered to be the standard surgery for phallic reconstruction. Urethral fistula is the most common complication reported in RFFFP and may reach up to 60-70%. Most commonly, the fistula site is at the anastomosis between the native urethra and the neo-urethra. Objective `- to study the impact of gracilis muscle flap wrapping around the native urethra/neo-urethral anastomosis on decreasing the fistula rate. Methods `- A prospective study was conducted at our urology department, from January 2018 till December 2020. - Patients presenting with a micropenis (Stretched penile length <7 cm) underwent RFFFP with gracilis muscle flap wrapping. - The free-flap was harvested from the non-dominant forearm. Under microscopic guidance, the radial artery was anastomosed with the inferior epigastric artery, the cephalic vein with the great saphenous vein, and the medial and lateral antecubital nerves with the ilio-inguinal and the dorsal penile nerves respectively. - A pedicled gracilis muscle flap was then wrapped around the neo-urethera/native urethral anastomosis to assess its possible role in decreasing the postoperative urinary fistula rate. Results `- Nineteen patients were included in the study with a median age of 26 years (16 - 43) and a BMI of 24 (22-25). The median hospital stay of 14 days (14 - 21) and the median follow-up was 11 months (4 - 13). The median cold ischemia time was 90 mins (70 - 100), estimated blood loss was 500 cc (400 - 500) and operative time was 11 hrs (10 - 12). - A viable phallus was achieved in 13 patients (overall free flap survival 68.4%). - Of the successfully viable phallus cases, 8 cases (42.1%) were complicated by complete disruption of the urethra and the remaining five cases (26.3%) had complete urethral tube. - One case of them developed a fistula at the neo-urethera/native urethral anastomosis, one case had a distal fistula and one case had a ring stricture at the site of anastomosis. - The gracilis muscle flap prevented urethral fistula formation in 4 out of 5 cases (80%) with complete urethral tube. Conclusions `- The use of pedicled garcilis muscle flap wrapping around the neo-urethra/native urethral anastomosis during RFFP might be helpful in reducing the urinary fistulae rates at this site. However, larger comparative studies are needed. Disclosure No