[The effects of vascular endothelial growth factor on survival of reverse flow axial skin flaps]

To research the effects of vascular endothelial growth factor (VEGF) on the survival of reverse flow axial skin flaps.

A 8 cm x 2 cm full thickness transverse dorsal flap based on right deep circumflex iliac artery was elevated in 20 Sprague-Dawley rats, which length crossing midline was 4.0 cm. The rats were randomized into two groups:experimental group n = 10), subcutaneous VEGF injections into the flap (200 ng, 200 microl) after flap elevation; control group (n = 10), subcutaneous saline injections into the flap (200 microl) after flap elevation. The flap was immediately sutured to its recipient beds then the injection was executed. Seven days after operation, the survival area of flaps and density of vessels were observed and measured, meanwhile its histological representation of the flaps was examined.

After 7 days of recovery, the mean survival area of flaps was 15.55+/-0.27 cm2 in experimental group and 13.42+/-0.57 cm2 in control group. The difference was significant between experimental group and control group (P<0.01). The mean vessel density of flaps was 21.00+/-3.16 in control group and 34.40+/-3.75 in experimental group. The difference was significant between experimental group and control group (P < 0.01). Histological analysis demonstrated that a qualitatively greater amount of granulation tissue, regular collagen fiber and a lot of fibrillated cells were observed in experimental group. Erythrocytes were leaked out from vessels, and inflammatory cells were observed around in control group.

In early survival of flaps, the VEGF can improve the survival of a reverse flow axial skin flap through improving angiogenesis and increasing the perfusion of vessel. It is an effective method of improving the survival of reverse flow axial skin flaps that VEGF is fully injected in subcutaneous flaps by single, when flaps are elevated.