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[Ablation of venous valves with Nd-Yag laser--an alternative to conventional valvulotomy?].

The careful removal of venous valves during in situ venous bypass procedures is a problem that has not been completely solved. In this experimental study, valve ablation with the Nd-Yag laser was compared with conventional valvulotomy. The investigation was performed in vitro using human vein segments with a length of 20 cm. Conventional valvulotomy was performed 16 times, 20 valves were removed with a 400 mu-fibre and 26 with the hot tip. The results were evaluated by endoscopy, light and electron microscopy. There were no vein perforations with the valvulotome and the hot tip. Endothelial damage was documented in 85% with the valvulotome and was reduced significantly to 58% with the 400 mu-fibre. With the hot tip endothelial lesions were seen in only 30%. Valve remnants were always present with the valvulotome and in no more than 15% with the hot tip. Electron microscopy supported these results in general. There was no endothelial damage in 69%.