Experimental studies of skin flaps with subcutaneous veins.

The authors have previously reported that skin flaps with subcutaneous veins nourished by arterial or venous inflow survived, despite being sited on recipient beds with poor circulation. In these previous studies, experimental models were based on axial pattern flaps of rabbit ears. However, for clinical application, there are problems in the use of axial pattern flaps with central vessels. This report classifies skin flaps with subcutaneous veins and produces experimental models that are suitable for clinical application and investigation of survival rates. Thirty-seven rabbits (74 ears) were used in this study. A 3.0-cm x 4.5-cm skin flap with only a "passing" vein (one that traveled through the tissue without major branches to that tissue) was raised at the level of the perichondrium on the dorsum of the auricular cartilage. The flaps were divided into three groups: Group A--composite flaps (n = 10); Group B--totally venous perfused flaps (n = 30); and Group C--afferent arterialized venous perfused flaps (n = 34). More than 80 percent of the flaps became necrotic in Group A. In Group B, 18 of 20 survived with partial superficial necrosis and two became more necrotic. In Group C, 18 of 21 flaps survived with superficial necrosis and three became more necrotic. Microangiographically, as concerns the "passing" veins in Groups B and C flaps, all of the flaps survived with only superficial necrosis. The skin flaps with subcutaneous veins survived as total venous perfusion flaps (TVPF) and as arterialized afferent venous perfusion flaps (AAVPF) even though the artery was not included in the flap. The experimental model is suitable for the investigation of the clinically unconventional flap.