Effectiveness of the proximal medial branch in DIEP flaps for breast reconstruction using Hartrampf zone IV

Abstract

BackgroundWhen performing breast reconstruction using a deep inferior epigastric artery perforator (DIEP) flap, including Hartrampf zone IV, the bipedicled DIEP flap has been argued to be necessary to ensure stable perfusion. However, a proximal medial branch (PMB), which is the most proximal perforator of the deep inferior epigastric artery, may make it possible to obtain adequate perfusion in a unilateral DIEP flap. This study aimed to clarify the detailed anatomical characteristics of PMB and its potential clinical application in breast reconstruction. MethodsThis retrospective study was conducted on breast reconstruction using the DIEP flap between May 2020 and July 2023. Data on PMB anatomy were collected from preoperative contrast-enhanced computed tomography angiography, and contralateral perfusion of the flap was estimated using intraoperative indocyanine green angiography. ResultsThe PMB was present in approximately 85% of cases, arising near the lateral border of the rectus abdominis, branching caudomedially in over half of the cases, and perforating 2.3cm laterally and 8.8cm caudally on average from the umbilicus. The average perfusion area of both zones II and IV significantly expanded to 96.5% and 74.2%, respectively, when the PMB was included in the DIEP flap, and 9 of 22 cases showed contrast extending to the entire zone IV. ConclusionsThe use of the DIEP flap with PMB is a good option for substantial-volume breast reconstruction. When utilizing the PMB, it is important to consider its specific anatomy, location of the main perforator, and pedicle length.