The branching pattern of the deep inferior epigastric artery revisited in-vivo: a new classification based on CT angiography.

The deep inferior epigastric artery (DIEA) is a reliable pedicle in the design of DIEA perforator flaps, with variations in its anatomy infrequent. Previous studies describing its branching pattern have all been based on cadaveric anatomy and described the following three branching patterns: Type 1 (single trunk), Type 2 (bifurcating trunk), and Type 3 (trifurcating trunk). The increased use of preoperative imaging, particularly with computed tomographic angiography (CTA), has enabled visualization of the DIEA and its branches in vivo, providing a functional view of this anatomy. We undertook a study of 250 patients (500 hemiabdominal walls) undergoing preoperative CTA before DIEA perforator flaps for breast reconstruction. The branching pattern of the DIEA and correlation to the contralateral hemiabdominal wall were assessed. The branching patterns of the DIEA were found to be different in vivo compared with cadaveric studies, with a higher than previously reported incidence of Type 1 patterns and lower than reported incidence of Type 3 patterns, and that some patterns exist which were not included within the previous nomenclature (namely, Type 0 or absent DIEA and Type 4 or four-trunk DIEA). There was also shown to be no overall concordance in the branching patterns of the DIEA between contralateral sides of the same abdominal wall; however, there was shown to be a statistically significant concordance in cases of a Type 1 DIEA (51% concordance, P = 0.04). As such, a new modification to the classification system for the branching pattern of the DIEA is presented based on imaging findings.