Preoperative estimation of vertical profunda artery perforator flap weight using computed tomography angiography for breast reconstruction

Abstract

AbstractBackgroundThe vertical profunda artery perforator (v‐PAP) flap is limited in terms of the tissue volume that can be harvested but is a suitable graft for Japanese patients with relatively small breast sizes. The objectives of this study were to identify the parameter most closely correlated with v‐PAP flap weight on computed tomography angiography (CTA) images and to create an easy‐to‐use v‐PAP flap weight estimation formula by linear regression analysis using the identified parameter.Patients and MethodsThirty v‐PAP flaps in 25 patients who underwent breast reconstruction were retrospectively analyzed. Mean age was 46.1 (range: 32–73) years, and mean BMI was 20.0 (range: 15.3–23.6) kg/m2. On a CT horizontal section of the thigh taken at level of the center of the long axis of the flap, the following parameters were measured from the anterior margin of the gracilis muscle to the posterior margin of the semimembranosus muscle using image processing software: fat area, fat thickness, thigh circumference, and skin paddle area. Linear regression analysis was then performed with the weight of the harvested v‐PAP flap as the objective variable and the above parameters as explanatory variables to predict skin flap weight.ResultsCorrelations with v‐PAP flap weight of each parameter were as follows: r = 0.66 (p < .0001) for fat thickness, r = 0.32 (p = .081) for total thigh area, r = 0.36 (p = .054) for thigh circumference, r = 0.27 (p = .153) for skin paddle area, and r = 0.84 (p < .0001) for fat area. Thus, the fat area had the strongest correlation with v‐PAP flap weight. The v‐PAP flap weight estimation formula obtained by linear regression analysis including fat area was as follows: 7.3 × fat area + 114 (coefficient of determination: R2 = 0.70, p < .0001, RMSE = 24). The engraftment rate of the 30 v‐PAP flaps was 100%. One patient developed postoperative venous thrombosis at the vascular anastomosis site, but underwent successful microsurgical revision, leading to flap salvage. During the >6‐month follow‐up period, there were no notable complications in the reconstructed breasts and donor sites.ConclusionsThe v‐PAP flap weight estimation formula we developed in this study showed a high correlation with measured values, allowing for easy estimation using only a single CTA horizontal section of the thigh.