Relationship Between Wound Complication Rates after Breast Reconstruction and Fluorescence Ratio of SPY Indocyanine Green Immunofluorescence: A Quantitative Study

Abstract

INTRODUCTION: Wound complications are dreaded outcomes of breast reconstruction and can be reduced by adequate perfusion of the mastectomy flap. The use of SPY (Novadaq) immunofluorescence technology gives a quantitative estimate of tissue perfusion. Our study aims to determine what percentage perfusion scores obtained from SPY imaging correlate with development of wound complications after breast reconstruction. METHODS: All female adult patients undergoing immediate breast reconstruction in which SPY was used intraoperatively from January 2018 through January 2021 were reviewed. There were 60 patients with 72 individual breast images. Demographics, number of reoperations, and postoperative wound complications were studied. Major wound complications were determined as return to the operating room for debridement or wound revision. Percent perfusion values were collected at various places on the flap: the incision margin (perfusion at margin, PAM), the lowest percent perfusion (LPP), the highest percent perfusion (HPP), and the average percent perfusion (APP) in the image. RESULTS: Wound complication rates were significantly higher when perfusion scores were lower for all 4 perfusion scores. Using ROC analysis, a cutoff LPP score of 22.5% and above showed a 91.4% negative predictive value (NPV; p = 0.01) and PAM of 33.5% and above showed a 83% NPV (p = 0.01) for having a major wound complication. The LPP, APP and PAM were negatively correlated with the number of re-operations. CONCLUSION: Our study provides a quantitative cutoff value to predict major wound complications in patients undergoing breast reconstruction.