The importance of the superficial venous anatomy of the abdominal wall in planning a superficial inferior epigastric artery (SIEA) flap: case report and clinical study.

The importance of the venous drainage of the anterior abdominal wall to free tissue transfer in deep inferior epigastric artery perforator flap surgery has been highlighted in several recent publications in this journal, however the same attention has not been given to superficial inferior epigastric artery (SIEA) flaps, in which the flap necessarily relies on the superficial venous drainage. We describe a unique case, in which the presence of two superficial inferior epigastric veins (SIEVs) draining into separate venous trunks was identified. The use of only one trunk led to a well-demarcated zone of venous congestion. A clinical study was also conducted, assessing 200 hemiabdominal walls with preoperative computed tomographic angiography imaging. The presence of more than a single major SIEV trunk was present in 80 hemiabdominal walls (40% of overall sides). There was considerable variability in the source of drainage of the SIEV, draining variably into the deep inferior epigastric vein, the great saphenous vein, the saphenous bulb, a common trunk with the superficial circumflex iliac vein or a common trunk with a second branch of the SIEV. These findings highlight the considerable variation in the number of SIEV trunks as well as their source of regional drainage, and show the importance of consideration of such variation.