Cephalometric Comparison of Transgender Women Following Facial Feminization Surgery to Assigned Female at Birth Subjects

Abstract

Objective: Facial feminization surgery (FFS) consists of a set of procedures utilized in gender-affirming care. With the goal of transforming masculine craniofacial features to more anthropomorphically feminine ones, these procedures are performed to increase congruence between the patient physical appearance and self-identified gender. However, the literature characterizing the femininity of FFS postoperative results is limited. The present study addresses the discrepancy through a three-dimensional cephalometric comparison. Methods: Patients who underwent frontal sinus setback, suprabrow contouring, genioplasty, and gonial angle reduction and received postoperative computed tomography imaging were identified. Craniofacial landmarks were placed to define regions of interest for cephalometric measurements including volume, surface area, and region-specific parameters. A set of control measurements was calculated for comparison from a cohort of 5 assigned female at birth (AFAB) subjects. Similarity of postoperative and AFAB measurements was calculated and compared for forehead, chin, and gonial angle procedures using analysis of variance and pairwise t test analysis. Results: Analysis of 80 FFS patients revealed that genioplasty had a significantly higher AFAB similarity score for surface area measurements than forehead procedures (P < 0.05). Genioplasty volume was significantly more similar to the AFAB parameter than the gonial angle reduction volume (P < 0.001). Conclusions: The present study, to our knowledge, is the most comprehensive and quantitative comparison of FFS postoperative results to AFAB subjects. Genioplasty had greater AFAB similarity than forehead and gonial angle reduction. Incongruencies between FFS and AFAB controls offer lessons for gender-affirming surgeons.