Temporal lobe perfusion asymmetries in schizophrenia.

Abstract

Structural and functional neuroimaging techniques have consistently demonstrated that abnormal lateralization of temporal lobes may be important in identifying the pathophysiologic processes in schizophrenia. The exact nature of these reported abnormalities has not been consistent. We examined temporal lobe perfusion using HMPAO-SPECT in 22 individuals with schizophrenia in an effort to establish whether temporal lobe perfusion asymmetry is seen in these individuals, as compared to a group of 22 age- and sex-matched controls. We found that the asymmetry index, a measure of perfusion differences between two homologous compared areas, was lower (more negative) in schizophrenic individuals. The asymmetry indices of patients considered with the results from globally corrected ROI means indicated that the left temporal lobes of individuals with schizophrenia were significantly hypoperfused when compared to controls. This finding does not appear to be caused by medication effects, demographic variables, handedness, imaging artifacts or analysis techniques. In our sample, patients with schizophrenia appear to have significant left hypoperfusion relative to right of their temporal lobes. Abnormal lateralization of temporal lobe blood flow may have important clinical implications by assisting with diagnosis and appropriate treatment for individuals with schizophrenia.