Background: Indocyanine green angiography (ICG-A) is a useful tool for evaluating mastectomy skin flap (MSF) perfusion during breast reconstruction. However, a standardized protocol for interpreting and applying MSF perfusion after mastectomy has not been established yet. The purpose of this study is to establish criteria for assessing MSF perfusion in immediate implant-based prepectoral breast reconstruction while correlating ICG-A findings with postoperative outcomes METHODS: This prospective observational study was conducted at a single institution and involved patients with breast cancer who underwent mastectomy and immediate implant-based prepectoral breast reconstruction between August 2021 and August 2023. The terms “hypoperfused flap” and “hypoperfused area” were defined according to ICG-A perfusion. MSF exhibited < 30% perfusion, excluding the nipple and the corresponding region, respectively. Data on the hypoperfused flap, hypoperfused area, and MSF necrosis were collected.
Results: Fifty-three breast cases were analyzed. Eight patients developed MSF necrosis (15.1%, 8/53). Of these, two patients underwent surgical debridement and revision within 3 months (3.8%, 2/53). There were nine cases of a hypoperfused flap, eight of which developed MSF necrosis. The hypoperfused flap was a significant predictor of the occurrence of MSF necrosis (p < 0.001). There was a tendency for increased full-thickness necrosis with a wider hypoperfused area.
Conclusions: The hypoperfused flap enabled the prediction of MSF necrosis with high sensitivity, specificity, positive predictive value, and negative predictive value. Considering the presumed correlation between the extent of the hypoperfused area and the need for revision surgery, caution should be exercised when making intraoperative decisions regarding the reconstruction method.