The DIEA branching pattern and its relationship to perforators: The importance of preoperative computed tomographic angiography for DIEA perforator flaps

BACKGROUND: Abdominal donor-site flaps based on the deep inferior epigastric artery (DIEA) are the most common flaps used in autologous breast reconstruction. With significant variation in the vascular anatomy of the DIEA, preoperative imaging is desirable. Computed tomographic angiography, recently described for this purpose, uniquely demonstrates the branching pattern of the DIEA. The authors sought to correlate the DIEA branching pattern to the location and course of perforators as a preoperative planning tool for perforator flaps. METHODS: Forty-five cadaveric hemi-abdominal walls were used for contrast injection of the DIEA with subsequent radiographic imaging. The branching pattern on radiography was thus correlated to the location and intramuscular course of perforators, from the main DIEA trunk to the point of the penetrating rectus sheath. RESULTS: The DIEA branching pattern correlated closely with the course of perforators. A bifurcating (type II) branching pattern demonstrated a reduced transverse distance traversed by each perforator, whereas a trifurcating (type III) branching pattern demonstrated significantly greater transverse distances (p = 0.0002). Type I vessels were intermediate. Vessel branching type, however, displayed no significant correlation with the number of perforators (p = 0.56). CONCLUSIONS: The distances traversed by perforators were significantly reduced with a bifurcating branching pattern of the DIEA, particularly those originating from the lateral branch, and were greatest with a trifurcating branching pattern. Increased transverse distances correlate with greater rectus muscle sacrificed during perforator flap surgery. As computed tomographic angiography is the optimal modality for demonstrating this pattern preoperatively, the authors suggest its use for preoperative assessment in transverse rectus abdominis musculocutaneous and DIEA perforator flaps.