Prof K C Dube Poster Award

Abstract

INTRODUCTION:Clinical, neurophysiological and functional neuroimaging studies in schizophrenia suggest impaired frontal lobe function, especially of the dorsolateral prefrontal cortex (DLPFC). Prefrontal dysfunction has been found to be associated with negative symptoms. Despite these findings, structural neuroimaging studies have failed to show consistent abnormalities in the frontal lobe. This may be because existing techniques are not sensitive enough to detect structural abnormalities or that dysfunction in the frontal lobe is caused by lesions elsewhere.AIM:We aimed to measure N-acetylaspartate (NAA), a neuronal marker, to evaluate the neuronal integrity of the dorsolateral prefrontal region in schizophrenic patients with persistent negative symptoms and in healthy comparison subjects, using proton magnetic resonance spectroscopy (1H-MRS).METHODOLOGY:Thirty six patients who fulfilled ICD-10 criteria for schizophrenia and with SANS score of more than 20 were compared to 15 healthy controls matched for age and gender. Proton Magnetic Resonance spectra were collected from the left dorsolateral prefrontal region with a voxel size of a 1.5cm3. In vivo 1H-MRS analyses were processed using Tarquin 4.3.10 software. Total NAA corresponding to the sum of NAA and N-Acetyl-Aspartyl-Glutamate (NAAG), was determined. NAA levels were calculated relative to the unsuppressed water signal from the same voxel.RESULTS:There were no significant differences between the two groups for NAA levels. There was no significant correlation between severity of symptoms and NAA concentration in the schizophrenic patients.CONCLUSION:The lack of significant mean difference in NAA between the two groups suggests that there is no marked neuronal loss in the dorsolateral prefrontal region in schizophrenia.