Background : Feminizing Mammoplasty in the transfemale has unique challenges specific to the natal male chest and hormone therapy. As proposed by Branford et al in 2014, standard ideal breast dimensions include a 45:55 ratio of upper pole to lower pole volume, a gentle upward angle to the nipple (approximately twenty degrees), gentle concavity to the upper pole, with a smooth convexity to the lower pole. We utilized these established guidelines for the ideal female breast to quantitatively evaluate implant type effects on achieving optimal breast parameters.
Methods : A retrospective review of a single surgeon’s feminizing mammoplasty cohort was performed, utilizing post-operative photographs and operative reports for implant type. Each breast was analyzed independently, with 10 total smooth implant breasts and 32 anatomic/shaped implant breasts. The three-quarter lateral view was utilized to measure upper pole and lower pole ratios using the inframammary fold (IMF) to nipple for the lower pole, and nipple to upper border of the breast for the lower pole. Since we utilized the ratio as an absolute number, the variable focal distance was irrelevant. Gentle upper pole concavity, smooth lower pole convexity, and direction of nipple were all recorded as binary values of yes or no. Paired t-tests were utilized to compare pre and post-operative data, and t-tests with unequal variance were utilized to compare anatomic and shaped implants.
Results : With respect to achieving upper pole fullness with a gentle concavity post-operatively, both anatomic and round implants achieved convexity rather than concavity in upper pole slope (p
Conclusions : Anatomic implants have come under recent scrutiny due to the ubiquitous use of surface texturing and the association with BIA-ALCL (breast implant associated anaplastic large cell lymphoma). Regardless, many plastic surgeons in the United States, and especially Europe and Australia, still utilize these shaped implants for the proposed benefits. Our data suggests that the one potential benefit of shaped implants may be improved lower pole convexity and smooth contour. Our study was limited to a single surgeon. A larger-scale prospective study is warranted to best determine if there is a role for shaped implants despite the risk for ALCL in feminizing mammoplasty.