Koshima 1989 - BJPS - DIEP

Summary

The inferior epigastric artery skin flap without rectus abdominis muscle is presented as an alternative to the conventional rectus abdominis musculocutaneous flap. This flap overcomes two main disadvantages of the rectus flap - bulkiness due to the muscle, and risk of abdominal herniation from removing the muscle.

Two case reports are presented. In the first, a 28x17cm inferior epigastric artery skin flap without muscle was raised in a 64 year old man to reconstruct a groin defect after tumor resection. The flap was based on a single muscle perforator from the inferior epigastric artery and vein. It survived completely except for a small area of necrosis at the distal end which required a skin graft. There was no abdominal wall herniation.

The second case was in a 44 year old man needing oral floor reconstruction after partial tongue resection for cancer. A 13x6cm free inferior epigastric artery skin flap without muscle was raised based on a single muscle perforator and microsurgically transferred. The flap survived completely without complications.

The key findings from the two cases are:

• Large flaps up to 28x17cm can survive on a single perforator from the inferior epigastric artery.

• Donor sites heal well with split skin grafts without risk of abdominal herniation as the rectus muscle is left intact.

• These flaps avoid the bulkiness of the conventional rectus abdominis musculocutaneous flap.

• The territory of the skin flap may be similar to a TRAM flap, although extension inferior to the inguinal ligament led to distal necrosis in the first case.

• Dissection and division of small muscle branches around the perforator allows it to be freed from the muscle and the flap raised.

• At least one suitable perforator can be found within the upper third of the lower abdomen down to the umbilicus.

In conclusion, the inferior epigastric artery skin flap without muscle provides a refinement of the rectus flap, overcoming its main limitations of bulkiness and abdominal wall weakness, while providing a large well vascularized flap for reconstruction of various defects. It offers advantages of less donor site morbidity and easier insetting compared to the musculocutaneous flap. Further experience will better define the safe dimensions and skin territory of this flap.