Restenosis after pulsed laser irradiation

This study was designed to assess the depth and extent of chronic lesions induced by clinically relevant doses of excimer or Ho:YAG laser irradiation in an animal model of normal arterial wall. Normal iliac arteries of 14 male New Zealand rabbits were irradiated with excimer laser and 7 contralateral sites were irradiated with Ho:YAG laser. The lasers were coupled to a 1.4 and 1.5 mm multifiber wire guided catheter for excimer and Ho:YAG laser, respectively. The catheter was introduced through the carotid artery and positioned coaxially over the guide wire into the common iliac artery. After 28 days the irradiated sites were excised for light microscopy. Arterial wall lesions were assessed at the site of irradiation and at 30 mm antegrade to the site of intervention. (1) Excimer and Ho:YAG induce chronic arterial wall damage, which may result in accelerated restenosis. (2) Ho:YAG results in deeper and more extensive lesions than excimer. (3) Both lasers induce an initial vasodilation in the irradiated vessel which disappears at follow-up.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.