HISTOLOGICAL-CHANGES IN BRAIN-TISSUE AND VASCULATURE AFTER INTRACAROTID INFUSION OF ORGANIC-SOLVENTS IN RATS

Organic solvents, such as ethanol or dimethyl sulphoxide (DMSO), have been used in liquid embolic agents. To investigate the effects of thes e solvents on the cerebral blood vessels and cerebral tis sue, we subj ected Wistar rats weighing 250-300 g to internal carotid artery infusi on of 0.2 mi diluted ethanol (10 %, 40 % or 70 %) or anhydrous DMSO (1 00 %). Some rats were sacrificed 5 min after the infusion and the rema inder at 10 days. Rats injected with ethanol at high concentration or DMSO showed extensive exudation of Evans blue at the site of injection 5 min after infusion, together with full-thickness necrosis of the wa ll of vessels and swelling of brain cells, In contrast, rats injected with 10% or 40 % ethanol solution showed necrosis of only the intimal layer and partial necrosis of the medial layer and no brain swelling w as observed. These findings suggest that ethanol at low concentration can be used as a relatively safe solvent for liquid embolic substances .