INTRODUCTION: In the last years, there have been reports of abnormalities in brain blood flow of cocaine abusers, detected by single photon computed emission tomography (SPECT). This abnormal pattern of brain perfusion has been associated with cognitive impairments but not with changes that could be seen by the use of structural neuroimaging techniques. One of the problems with most of the published papers on the subject is the inclusion of a large number of heroin users in the studied samples. Heroin also seems to affect the pattern of brain perfusion, particularly during withdrawal states. METHODS: Fourteen cocaine-dependent inpatients (none of them under the use of opiates) and 14 healthy volunteers (control group) were submitted to 99m-technetium ethyl-cysteinate dimer SPECT. The analysis of SPECT exams was made by visual qualitative analysis of the reconstructed images (standard method in clinical practice), performed by a radiologist unaware of the subjects' diagnoses. RESULTS: Visual analysis showed a pattern suggestive of irregularities in the cerebral blood flow in nine patients, but in only two controls (p = 0.018; two tailed Fisher's exact test). CONCLUSIONS: Abnormal brain circulation may be related to cognitive impairments reported in cocaine dependent subjects. Although brain perfusion deficits associated with cocaine use may be irreversible, there have been reports in the literature of treatments for these blood flow changes. There are abnormalities in the cerebral blood flow associated with cocaine dependence even in the absence of opiate abuse or dependence.
Cocaine; Crack; Substance abuse; Cerebral blood flow; SPECT
