Innovative DIEP flap perfusion evaluation tool: Qualitative and quantitative analysis of indocyanine green-based fluorescence angiography with the SPY-Q proprietary software

Background: Perfusion-related complications remain the most common concern in DIEP flap breast reconstruction. Indocyanine green-based fluorescence angiography can be used for the real-time intra operative assessment of flap perfusion. The SPY Elite system is the most widely used device in this setting. The main objective was to describe the use of SPY-Q proprietary software to perform qualitative and quantitative analysis of flap perfusion. Methods: This retrospective cohort study was performed at the Curie Institute between 2013 and 2017. We included patients undergoing unilateral DIEP flap breast reconstruction for whom indocyanine green-based angiography videos were of sufficient quality for analysis. Videos were recorded with the SPY Elite System and analyzed with SPY-Q proprietary software. Results: We included 40 patients. We used real-time dynamic color analysis to describe three different patterns of flap perfusion. SPY-Q proprietary software provides quantitative flap perfusion parameters. Our quantitative analysis confirmed that zone I is the best perfused part of the flap and zone IV the less perfused one. There was no significant association between flap perfusion pattern and perforator anatomy, patients’ clinical characteristics or postoperative outcomes. After exploratory univariate analysis, quantitative perfusion parameters were significantly impaired in young patients with diabetes mellitus or under hormone therapy by tamoxifen. Conclusions: We here describe a new approach to assess DIEP flap perfusion using the SPY Elite System proprietary software. It provides interesting qualitative and quantitative analysis that can be used in further studies to precisely assess DIEP flap perfusion.