Time course and spatial distribution of neodymium: yttrium-aluminum-garnet (Nd:YAG) laser-induced lesions in the rat brain

Journal Article · Mon Apr 01 04:00:00 EST 1985 · Neurosurgery; (United States)

DOI:https://doi.org/10.1227/00006123-198504000-00001· OSTI ID:5241141

Eggert, H R; Kiessling, M; Kleihues, P

Cerebral lesions made by focal neodymium:yttrium-aluminum-garnet (Nd:YAG) laser irradiation of the rat forebrain were studied in adult Wistar rats. For the analysis of time-dependent changes, the brains of 28 animals were irradiated with a constant energy density of 461 J/cm/sup 2/. In this series, survival time ranged from 0.5 hours to 80 days. Immediately after irradiation, a circular lesion appeared on the surface of the brain. This lesion was surrounded by an edematous area intensively stained with Evans blue. At energy levels higher than 30 J, this circular edema contained numerous thrombosed vessels. Histopathologically, the lesion consisted of three distinct zones: the central coagulation necrosis was surrounded by a zone of delayed colliquation necrosis and by perifocal edema. At approximately 80 days after irradiation, the resulting cortical defect was covered by a pial membrane. Edematous changes of the brain cortex and the adjacent white matter were observed as early as 1 hour after irradiation. In a second experiment, the energy density varied from 231 to 3077 J/cm/sup 2/. This series consisted of 84 animals that were allowed to survive 48 hours. The size of the lesion depended on the level of energy applied, but the depth of the lesion varied less than the diameter at the brain surface.

• Research Organization: Univ. of Freiburg, Germany, F.R.
• OSTI ID: 5241141
• Journal Information: Neurosurgery; (United States), Journal Name: Neurosurgery; (United States) Vol. 4; ISSN NRSRD
• Country of Publication: United States
• Language: English

Related Subjects

560400* -- Other Environmental Pollutant Effects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BIOLOGICAL EFFECTS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
DISTRIBUTION
EDEMA
ELECTROMAGNETIC RADIATION
LASER RADIATION
LASERS
MAMMALS
NECROSIS
NEODYMIUM LASERS
NERVOUS SYSTEM
ORGANS
PATHOLOGICAL CHANGES
RADIATIONS
RATS
RODENTS
SOLID STATE LASERS
SPATIAL DISTRIBUTION
SYMPTOMS
VERTEBRATES