通過静脈皮弁移植の実験的研究とその臨床応用

Abstract

In recent years, conventional flaps which make a sacrifice of main arteries as reported frequently in the early stage of their development have been reevaluated in the field of flap surgery. This movement has facilitated development of flaps vascularized by perforating branches measuring about 0.3 mm in diareter, and has also thrown light on the merits of venous flaps which make no sacrifice of main arteries. Looking back on the history of venous flaps, they initially attracted attention because, in contrast to conven- tional flaps, 1) they do not make a sacrifice of main arteries, 2) they are not limited by the conditions of the recipient site, and 3) preparation of the flap is technically easy and applicable to emergency operations. Because of these advantages, venous flaps have been used widely in the clinical setting, but the mechasism of flap survival remains conjectural. The present study was designed to determine the limits of venous flap viability supplied by one vein, which is one of the questions related to venous flap stirvival. A flom-through venous flap measuring 3.0×3.0 cm was prepared in the lateral margin of the auricle in rabbits, and the area of flap viability was determined. The influences of surrounding blood circulation on the area of flap viability were also investigated. As a result the width of flap covered by one vein was 11.0±4.8 mm as a whole, whereas it was 18.1±6.2 mm in the presence of good blood circulation in the surroundings, showing a significant effect of surrounding blood circulation. Based on these experimental data, flow-through venous flaps were applied to 25 patients and the stability of the flaps was confirmed. The presence of arteriolar systems in perivenous tissues has been demonstrated recently. To provide the venous flap with blood flow from the arteriolar system is another way to improve the viability of venous flaps.