Single-voxel proton magnetic resonance spectroscopy of the pons and cerebellum in patients with schizophrenia: a preliminary study

Abstract

Magnetic resonance spectroscopy (MRS) is a non-invasive functional imaging technique that can measure various brain tissue metabolites such as N-acetylaspartate (NAA), choline (Cho), creatine-phosphocreatine (Cr), myo-inositol (mI) and other metabolites. Morphological studies have indicated the pons and cerebellum as possible sites of abnormal functioning in schizophrenic patients. This study examines schizophrenic patients for the presence of abnormalities in proton MRS ( 1H-MRS) measured metabolites in two regions of the posterior fossa. Twelve schizophrenic patients and eight non-schizophrenic control subjects were studied by measuring the ratios of NAA/Cr, Cho/Cr and mI/Cr from 1H-spectra obtained from the pons and right or left cerebellum using an integrated MRI/MRS protocol. Spectra were obtained from a voxel in the pons and voxels from the left and/or right lateral cerebellum. Data were analyzed in the absorption mode and fitted to Lorentzian lineshapes using a Marquart algorithm. Significantly lower NAA/Cr ratios were found in the pons of schizophrenic patients than in the control subjects, but not in the cerebellum. This study is the first to measure brain tissue metabolites using 1H-MRS in the pons and cerebellum of schizophrenic patients. Significant alterations of 1H-MRS metabolites may suggest the involvement of the posterior fossa as a part of the pathological substrate underlying schizophrenia.