Caudate size in first-episode neuroleptic-naive schizophrenic patients measured using an artificial neural network

Background: Structural brain imaging studies have demonstrated an increase in caudate volume in schizophrenic patients medicated with typical neurolep tics and a volume decrease following treatment with atypical neuroleptics, The measurement of striatal volume in patients who have never been treated with neuroleptics may indicate whether these changes are superimposed on in trinsic basal ganglia pathology in schizophrenia or are solely neuroleptic- induced. Methods: We studied 36 first-episode, neuroleptic-naive schizophrenic patie nts and 43 control subjects using an artificial neural network (ANN) to ide ntify and measure the caudate nucleus. The resulting volumes were analyzed using an ANCOVA controlling for intracranial volume, age, gender, and socio economic status. Results: The mean volume difference between the caudate nuclei of patients and control subjects was .297 mL, the caudate nuclei of the patients being smaller than those of controls. When we covaried for intracranial volume, t his was a statistically significant difference in caudate volume (n = 79; d f = 1,75; F = 4.18; p > .04). Conclusions: Caudate nuclei of neuroleptic naive schizophrenic patients are significantly smaller than those of controls. This suggests that patients suffering from schizophrenia may have intrinsic pathology of the caudate nu cleus, in addition to the pathology observed as a consequence of chronic ne uroleptic treatment. Biol Psychiatry 1999;46:712-720 (C) 1999 Society of Bi ological Psychiatry.