Low power CO2 laser-assisted microvascular anastomosis (LAMA) was used for saphenous artery autotransplantation in 40 rabbits. Eighty end-to-end anastomoses were performed by three methods (conventional interrupted suture, stay suture + laser, laser without stay suture). The long term patency rate in the three types of anastomosis is 93%, 93%, and 100%, respectively. The time needed for the laser procedure is half to one-third of that required for the interrupted suture method. The tensile strength of the bonding site can withstand up to 250 mm Hg of arterial pressure. We have demonstrated that the CO2 laser can be used in microvascular anastomosis with or without stay sutures. Aneurysm formation is a potential risk of LAMA. Accurate coaptation of the transected vessel, precise control of laser energy, and minimal area exposed to the laser beam are the key points for further improving anastomotic quality.

No abstract

A modified method of occluding the middle cerebral artery (MCA) by inserting a tiny copper wire into the lumen of the vessel to make a model for cerebral ischemia in the cat is described. Of 22 rats, 4 were controls and the remaining 18 were divided into two groups. Bipolar electrocoagulation was used in 9 cats and copper wire insertion was used in the other 9 to occlude the MCA through a transorbital approach. Two cats died after surgery and were excluded from this study. Of the 16 cats in two experimental groups, 13 of 14 showed hemiplegia and the other 2 were killed under anesthesia. Typical ischemic changes can be seen in the territory of the occluded MCA. Increased water content and decreased amplitude of somatosensory evoked potentials can be found in the ischemic hemisphere. Histochemical fluorescence study demonstrated that the sympathetic nerve fibers normally existing on the MCA can be completely destroyed by electrocoagulation but may remain intact with the copper wire method. This new method may have less influence on the vascular regulative function of the autonomic nervous system and be more similar to the pathological changes of cerebral infarction in man. We think our method can be useful for further research in cerebral ischemic disease and the regulative effects of the nervous system on brain vessels.