Refining the abdominal wall perforasome with clinical application.

[BACKGROUND AND PURPOSE] Perforator selection is critical during operative planning for deep inferior epigastric artery perforator (DIEP) flap reconstruction. This study aimed to evaluate the anatomical variations in deep inferior epigastric artery (DIEA) perforators and their primary subcutaneous branching patterns within the perforasome, using three-dimensional computed tomography angiography (CTA) to develop a new nomenclature system.

[METHODS] Abdominal CTA scans of 180 patients undergoing preoperative imaging for DIEP flap reconstruction were evaluated. Maximum intensity projection (MIP) and volume-rendering technique (VRT) reconstructions were used to map perforator anatomy. Branching patterns were correlated to the location and subcutaneous course of the perforators, at emergence from the anterior rectus sheath.

[RESULTS] Perforators were classified into 3 main categories and further sub-classified based on the orientation of tributaries. Type I perforators were the most common (87.2%) and coursed as a single trunk (IA) or bifurcated with an internal angle ≤30° (IB). Type II perforators (7.5%) bifurcated at 180 ± 20° (IIA) or between 30° and 160° (IIB). Type III perforators (5.3%) produced 3 or more primary branches. On an average, there were 2.9 ± 1.6 perforators per hemi-abdomen. Larger caliber vessels were found closer to the umbilicus (P < 0.005). Most perforators (80.5%) exited the rectus sheath caudal to the umbilicus and coursed in an inferolateral direction.

[CONCLUSIONS] This study provides a novel classification of the primary subcutaneous perforasome branching patterns of DIEA perforators and highlights the clinical implications for improved flap design and operative outcomes.