[Comparison of right thalamus and temporal cortex metabolite levels of drug-naive first-episode psychotic and chronic schizophrenia in patients].

OBJECTIVE The aim of this study was to use Magnetic Resonance Spectroscopy (MRS) to investigate whether patients with chronic schizophrenia have different brain metabolite levels in the temporal cortex and thalamus than drug-naive first-episode patients. METHOD We compared right-handed male first-episode patients (n=13) and chronic schizophrenic cases (n=15) with gender- and handedness-matched controls (n=10). Right temporal and right thalamic N-Acetylaspartate (NAA)/Creatine (Cre), NAA/Choline (Cho), and Cho/Cre ratios were obtained with MRS. RESULTS Right temporal NAA/Cre, NAA/Cho, and right thalamus NAA/Cre ratios were significantly lower both in the chronic and first-episode patient groups when compared to normal controls (p<. 001), suggesting decreased neuronal integrity in both patient groups. There were no significant correlations between symptom severity and functional status with MRS variables (p=.027). These results suggested that both patient groups had neural integrity problems. Duration of illness (days) in the first-episode patients was significantly correlated with right temporal NAA/Cre and NAA/Cho. CONCLUSIONS These results suggested that first-episode and chronic patients had significantly impaired neural integrity, particularly in the temporal cortex. It seems that in the acute phase of the first-episode, neural integrity impairment increased along with days elapsed without treatment.