Experimental in-vivo study of laser-tissue interaction on the brain: influence of gaseous environment

Autor: Manuel Dujovny, Maria Cristina Chavantes, Federico Vinas, Lucia J. Zamorano, Ljubisa Dragovic
Rok vydání: 1990
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
DOI: 10.1117/12.17630
Popis: The present study attempted to assess the in vivo effects of Nd-YAG laser irradiation in different gaseous environments on liver and brain. Such an investigation is critical for determining the extent of injury under such conditions for improving further clinical applications. We intended to define the influence on laser-tissue interaction of Room Air, 30% Oxygen, Helium, and Nitrogen. The anesthetized rats were placed in a special chamber and kept breathtng via a tracheostomy tube to the outside, and craniotomy or laparotomy was performed. Nd-YAG laser fiber was directed with a fixed distance at the exposed brain/liver. The staining drug for brain study was 2,3,5 triphenyltetrazolium chloride, which was injected into the aorta before sacrificing the animals. The 44 rats studied were divided into: liver and brain groups. The resulting lesions were photographed macroscopically. In the liver group, statistical analysis showed that laser-liver tissue interaction in helium and nitrogen created a well defined and less hemorrhagic lesions. Macroscopically, in the brain group, we found that the target zones were well delineated with Nitrogen concentration. Moreover, we observed smaller lesions and more sharply defined areas with Helium concentration. In Room Air and Oxygen concentrations, more carbonized and bloodish lesions were found. Laser-tissue interaction in Helium and Nitrogen environments produces more sharply defined lesions with less involvement of the sorrounding tissue, less hemorrhagic lesions to the target, and reduce smoke production. This effect may be of benefit in clinical application of Nd YAG laser, where a more specific target-laser interaction could be achieved avoiding undesired complications due to penetration on the surrounding healthy tissue.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Databáze: OpenAIRE