Anatomy of the deep inferior epigastric artery perforator (DIEP) flap is unpredictable, which makes dissection of the flap tedious and increases the risk for inadvertent injury to the perforators. Futhermore, it is difficult to determine which perforators are important for perfusion of the flap. If insufficient perforators are selected, flap necrosis occurs. If too many perforators are selected, flap dissection becomes even more complex, and integrity of the rectus abdominis muscle can be compromised.

Pre-operative CT angiography is used to delineate the course of the deep inferior epigstric vessles, and to locate the perforators. Intra-operative tissue oximetry is used to gather information about the functional significance of each perforator. After the perforators are identified, baseline measurements are made. Then, in sequence, each perforator is temporarily occluded with a clamp, and tissue oximetery measurements are repeated. Thus, the contribution of each perforator to overall flap perfusion can be assessed. The insignificant perforators are divided without further dissection.

In the case demonstrated, we elevated the flap over the left inferior epigastric artery, and focused on two perforators based upon results of the CT angiogram. A perforator from each of the medial and lateral row was identified. Using tissue oximetry, the lateral perforator was found to be dominant, so the medial row perforator was sacrificed.

The video demonstrates our technique for refined DIEP flap design using CT angiography and intra-operative tissue oximetry. This may allow for more expedient and reliable preparation of the flap.