Microvascular anastomosis with a low-output carbon dioxide (CO2) laser. II. Histopathological features.

A low-output CO2 laser was applied for microvascular anastomosis. The healing process of the vessel wall was examined histopathologically using light and scanning electron microscopes, and compared with that following conventional suture anastomosis. A power level of 21-40 mW and an exposure time of 5-15 sec were used. Under these conditions the laser beam reached the adventitia and media but not the intima. This made it possible to perform microvascular anastomosis without causing damage to the intima. Inflammatory reactions in the vessel wall were milder and endothelialization of the lumen surface occurred somewhat earlier with the laser technique than with the conventional technique of manual suture anastomosis.