PC2. THREE-DIMENSIONAL TISSUE RENDERING AND VOLUME ANALYSIS OF A NOVEL MEDIAL THIGH FLAP USING CT ANGIOGRAPHY: THE CHIMERIC GRACILIS AND PAP FLAP

Abstract

PURPOSE: A common arterial pedicle supplying both gracilis and profunda artery perforator (PAP) flap perforasomes is a recently described anatomical variation, favoring the potential harvest of a chimeric gracilis and PAP flap. We sought to characterize this novel flap configuration with three-dimensional (3D) angiography. METHODS: Lower extremity CT angiograms were performed according to standard angiography technique: 5 ml/s contrast injection with bolus tracking. Thin slice (0.6mm) axial reconstructions created multiplanar and volume rendered 3D images. Post-processing (Visage 7.1.15b) consisting of vessel measurements and centerline reconstructions of gracilis and PAP pedicles. Tissues supplied by these vessels were identified by tracing perforator branches, tagging supplied muscle and overlying tissues using semiautomated volume selection. RESULTS: A total of 974 CT angiograms were reviewed, yielding a total of 1,940 lower extremities (RLE= 970, LLE= 970) for evaluation. A chimeric gracilis and PAP flap was found in 51% of patients (N=494/974). Average length of the common arterial pedicle was 31.1 ±16.5 mm (Range = 2.0-95 mm), with an average diameter of 2.8 ±0.7 mm (Range = 1.3-8.8 mm). Average length of downstream gracilis and PAP flap pedicles were 58.0 ±18.7 mm (Range = 9.8-123 mm) and 101.7±27.0 mm (Range = 42.2-183 mm) respectively. 3D rendering yielded an overview of chimeric flap anatomy, allowing for comprehensive volumetric assessment (197.1 ± 29.2 cm3) CONCLUSION: 3D rendering of a chimerically configured gracilis and PAP flap with CT provides an objective assessment of arterial anatomy, flap configuration, and tissue volume for potential use in a clinical setting.