The depressant actions of ethanol in the brain is known. SPECT is non invasive method to measure the regional cerebral blood flow (rCBF) and to evaluate indirectly the brain metabolism. The aim of the study is to evaluate morphologic and functional status of CNS using 99mTc-ECD SPECT in chronic alcoholics. METHODS Examined group consisted of 18 male alcoholic patients aged from 28 to 52 years (x = 42.1 +/- 5.4) treated at the Ward of Toxicology and Environmental Diseaes (Detoxification Unit). Only patients without prior head injury, CNS inflammatory changes, epilepsy, migraine, diabetes mellitus or other systemic injury were included. Alcohol dependence was diagnosed according to ICD-10 criteria. The intensity of withdrawal syndrome was measured using CIWA-A scale. The regional cerebral blood flow (rCBF) was measured using 99mTc-ECD SPECT with the double head E.CAM Siemens gamma camera. The reference group, necessary to obtain a normal values for the gamma camera applied, consisted of 31 healthy subjects (33.32 +/- 10.99 y). RESULTS The mean values of rCBF in all examined region of frontal and temporal lobes, and in basal ganglia bothsided were significantly lower in the group of alcoholic patients than in the control group. No significant difference between rCBF in occipital lobes except the occipital inferior region, and in parietal lobes except the parietal superior region. Symetrical hypoperfusion (rCBF-2SD) in the frontal lobes was stated in 11 (61.1%), in temporal lobes in 4 (22.2%), in parietal and occipital lobes in 3 (16.7%) of the patients examined. In 7 the patients examined rCBF disturbances in basal ganglia were found (bothsided in 4, leftsided in 2, and rightsided in 2 the patients). Focal rCBF changes in the parietal, frontal and temporal lobes localised mostly on the left hemisphere were stated in 27.8% of the alcoholics examined. In concusion, the metabolic disturbances and the brain morphological changes mostly in frontal and temporal lobes due to chronic alcoholism were detected in the pilot study. A further investigation on more numerous group of ethanol dependent patients and monitoring of the changes in alcoholics who maintain a long-term abstinence from alcohol is needed.