Effects of Nd-YAG laser radiation on different parts of arteries

Various dosage of Nd-YAG laser energy were adopted on the normal coronary artery, arotid àrtery, aorta and iliac artery （within 72 hours after death） and 155 slides from 70 pecimens of them were studied for the effects of Nd-YAG laser radiation upon normal arteries.There were vaporized craters in the center of exposed areas with charred lining and urrounding coagulated necrotic zone. The depth of vaporized crater was correlated possitively o the laser energy exposed （P＜0.01）. Partial penetration of the medial layer of similar ascular wall needs 30 joules for the coronary artery whereas 50-70 joules for the carotid rtery, aorta and iliac artery. It is necessary to have the maximum dose of laser energy to erforate the wall of aorta （140 joules）, as compared with other arteries.Since the thickness f essel is different from each other, the energy of laser adopted should be different. Lower ower density, shorter exposure time and non-continuous radiation of the laser are better for voiding the perforation of blood vessels. Different media affects the result of laser adiation ifferently. For example, the reaction is stronger in the blood than that in saline（P＜0.01）. hese data of quantitative effects of Nd-YAG laser on normal blood vessels are valuable as a reparation for the clinical application oflaser angioplasty.