Early and long-term evaluation of perfusion changes in free DIEP-flaps for breast reconstruction via IC-view and duplex ultrasound: autonomous or peripheral perfusion?

Controversy surrounds the question whether free flaps remain dependent for blood supply on their vascular pedicle or if there is an autonomization by neovascularization from the surrounding wound bed. This becomes important when flap shaping or repositioning are performed. Our study involved 23 patients who received a deep inferior epigastric perforator (DIEP) flap for breast reconstruction. IC-View laser video angiography (Pulsion Medical Systems AG, Munich, Germany) was executed immediately and 18 months postoperatively. Two zones (close and distant to the pedicle) and the contralateral breast were compared quantitatively. Via duplex ultrasound, late perfusion changes were measured to analyze flow volume, velocity, and diameter of the internal thoracic artery and the DIEP-flap pedicle. In the long term, early postoperative flap hyperperfusion changed to flap hypoperfusion. No enhanced flow from the flap surrounding into the flap borders was measured. These results might indicate a long-term increase in total peripheral vascular resistance of the transplanted tissue. Postoperative perfusion after 18 months remains dependent on the anastomosed vascular pedicle.