(285) DOES A SEPARATE BLOOD SUPPLY TO THE URETHRA DECREASE COMPLICATIONS IN TRANSMASCULINE GENDER AFFIRMATION SURGERY? OUTCOMES OF RADIAL ARTERY URETHROPLASTY IN A LARGE COHORT

Abstract Introduction Transmasculine gender affirmation surgery (tGAS) is a highly morbid procedure in which the most frequent complications are fistulas and strictures, especially at the phallus level. We hypothesized that the construction of the urethra using the radial artery urethroplasty (RAU) technique, since the urethra is constructed with its own separated blood supply, may lead to an overall lower incidence of complications compared to the integrated phallus urethra construction. Objective The purpose of this study is to examine the urethral complication profile after RAU. Methods We included patients undergoing tGAS in a three-stage procedure (neophallus-join up-penile prosthesis) between 2014 and 2019 collected from our prospective institutional database. Fistula/stricture occurrence after RAU was recorded and analyzed using the Chi-squared test and univariable logistic regression. Results 314 individuals with a median follow-up of 4.3y were included. Types of phalloplasty include forearm flap (80.6%), anterolateral thigh flap (7.6%), and abdominal flap with free flap urethroplasty (11.8%). 13% of the patients underwent RAU to construct the urethra or to treat a panurethral stricture following the neophallus construction. 90.2% of the RAU were performed after an abdominal flap. Patients undergoing RAU had a significantly lower number of fistulas/strictures at the phallus level compared to integrated urethras (9.7% vs 39.2%, p = <.001). Logistic regression confirmed RAU as a protective factor (OR = .17, p = .001). A slightly greater number of scrotal or perineal fistulas after the join-up stage were recorded after RAU, however, the finding was not significant (14.6% vs 8.1%, p = .17). Conclusions We confirmed the hypothesis that constructing the urethra with a separate vascularization from the phallus assures fewer fistulas/strictures in the phallus, likely because of the better blood supply. We found a non-significant slightly higher incidence of scrotal and perineal fistulas after the join-up stage in individuals who underwent RAU however, larger cohorts are needed to accurately evaluate this aspect. Disclosure No.