CO2 and Nd:YAG laser systems in microsurgical venous anastomoses.

A comparative study was undertaken in 81 rats to investigate a CO2 and Nd:YAG laser system for laser-welded anastomosis of the femoral vein. Conventionally sutured anastomoses (CMSA) served as controls. Laser-welded anastomosis (LAMA) was easier and could be performed 30% faster than CMSA. Postoperative investigations included patency tests, postmortem examinations and light and electron microscopy. Aneurysms were not seen. Foreign-body reaction was more pronounced in CMSA. Patency rates for CO2-LAMA and CMSA were equal, whereas Nd:YAG-LAMA resulted in significantly higher rate of early postoperative thrombosis (P less than 0.01). Because of its physical properties, the CO2-laser system seems to be better suited for laser welding of delicate structures such as the rat femoral vein.