Nonsuture microvascular anastomosis using an Nd-YAG laser and a water-soluble polyvinyl alcohol splint

Anastomosis of rat common carotid artery was performed without sutures, using a neodymium (Nd)-YAG laser at 20 W for 100 msec; this power and exposure had been found optimal in preliminary experiments. An intraluminal intervascular splint made of water-soluble polyvinyl alcohol, which dissolved and disappeared within a few minutes after recirculation of blood, was used for precise "intima-to-intima" coaptation. No stay sutures or glue were required during the procedure. There was a 92% patency rate 24 hours after surgery, and the anastomosed vessels were still patent on the 7th and 30th postoperative days. Complications such as aneurysm formation or stenotic change were negligible. The fusion of the muscle layer and collagen fibers of the media in the anastomosis was confirmed histologically. A tensile strength test immediately following operation and 1 week later showed that this anastomosis was significantly better than that achieved with the usual manual suture method. The major advantages of this technique, combined with use of a water-soluble polyvinyl alcohol splint, are rapidity, consistency of results, and firm fusion with no residual foreign body.