The employment of photoablative effect on coronary artery angioplasty has been a new exciting field as a treatment option. Guided by good results in the literature, our group decided to study the laser/tissue interaction on carotid arteries with the intent of a less invasive treatment of intracranial and extracranial obstmcted disease in vascular neurosurgery. We studied human carotid arteries from ten male autopsy specimens with an average age of 53 years (34-37 years old) which a total of 22 laser applications were perfonned. Using the same repetition rate and energy, 20 Hz and 30 mJ, we compared the effect of the laser energy on 'normal and "pathologic areas of the carotid arteries. The pathologic specimens, presenting calcified and non-calcified plaques, the same as the macroscopical "normal" specimens, were submitted to the energy of the Excimer Laser with 308 nm wavelength. The laser beam was delivered perpendicularly through continuous flushing of saline on the targeted artery wall varying from 200 to 4000 pulses.Histological studies were done and statistical analysis was performed. The results showed that the depth of penetration varied from 1 13 urn to 1200 urn, with a width of the lesion ranging from 150 um -1500 urn. In our study we found that the range between non-effective and destructive effect caused by the laser was around 400 pulses. We encountered minimal degree of carbonization while lasenng on calcified plaques. We concluded that Excimer laser is a feasible and secure tool to prevent thermical complications of laser treatment, which will allow neurosurgeons in the future athermic laser angioplasty. Progress in this field must rely on further in vitro and in vivo research, before it can be clinically applied as well as improvements in delivery systems.