An external validation of a novel predictive algorithm for male nipple areolar positioning: an improvement to current practice through a multicenter endeavor.
Floyd W Timmermans, Laure Ruyssinck, Sterre E Mokken, Marlon Buncamper, Kevin M Veen, Margriet G Mullender, Karel E Y Claes, Mark-Bram Bouman, Stanislas Monstrey, Timotheus C van de Grift
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引用次数: 1
Abstract
The correct positioning of nipple-areolar complexes (NAC) during gender-affirming mastectomies remains a particular challenge. Recently, a Dutch two-step algorithm was proposed predicting the most ideal NAC-position derived from a large cisgender male cohort. We aimed to externally validate this algorithm in a Belgian cohort. The Belgian validation cohort consisted of cisgender men. Based on patient-specific anthropometry, the algorithm predicts nipple-nipple distance (NN) and sternal-notch-to-nipple distance (SNN). Predictions were externally validated using the performance measures: R2-value, means squared error (MSE) and mean absolute percentage error (MAPE). Additionally, data were collected from a Belgian and Dutch cohort of transgender men having undergone mastectomy with free nipple grafts. The observed and predicted NN and SNN were compared and the inter-center variability was assessed. A total of 51 Belgian cisgender and 25 transgender men were included, as well as 150 Dutch cisgender and 96 transgender men. Respectively, the performance measures (R2-value, MSE and MAPE) for NN were 0.315, 2.35 (95%CI:0-6.9), 4.9% (95%CI:3.8-6.1) and 0.423, 1.51 (95%CI:0-4.02), 4.73%(95%CI:3.7-5.7) for SNN. When applying the algorithm to both transgender cohorts, the predicted SNN was larger in both Dutch (17.1measured(±1.7) vs. 18.7predicted(±1.4), p= <0.001) and Belgian (16.2measured(±1.8) vs. 18.4predicted(±1.5), p= <0.001) cohorts, whereas NN was too long in the Belgian (22.0measured(±2.6) vs. 21.2predicted(±1.6), p = 0.025) and too short in the Dutch cohort (19.8measured(±1.8) vs. 20.7predicted(±1.9), p = 0.001). Both models performed well in external validation. This indicates that this two-step algorithm provides a reproducible and accurate clinical tool in determining the most ideal patient-tailored NAC-position in transgender men seeking gender-affirming chest surgery.
期刊介绍:
The purpose of the Journal of Plastic Surgery and Hand Surgery is to serve as an international forum for plastic surgery, hand surgery and related research. Interest is focused on original articles on basic research and clinical evaluation.
The scope of the journal comprises:
• Articles concerning operative methods and follow-up studies
• Research articles on subjects related to plastic and hand surgery
• Articles on cranio-maxillofacial surgery, including cleft lip and palate surgery.
Extended issues are published occasionally, dealing with special topics such as microvascular surgery, craniofacial surgery, or burns. Supplements, usually doctoral theses, may also be published.
The journal is published for the Acta Chirurgica Scandinavica society and sponsored by the Key Foundation, Sweden.
The journal was previously published as Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery.