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It has recently been suggested that new imaging methods such as magnetization transfer imaging (MTI) may play an important role in detecting subtle gray- and white-matter abnormalities in schizophrenia. The aim of the study was to investigate whether MTI, analyzed on a voxel-by-voxel basis, could identify areas of abnormal magnetization transfer ratio (MTR) in patients with schizophrenia.Twenty schizophrenic patients and 23 healthy controls matched for handedness and demographic variables underwent MTI and T1-weighted structural MRI in a 3-tesla scanner. Post-processing was performed with SPM99 and included co-registration of the MT-weighted and non-MT-weighted images, calculation of the MTR maps, spatial normalization, and smoothing. Differences in the MTR maps between groups were assessed using two-sample t-tests. Significant changes in MTR were detected at an individual voxel threshold of p0.05.Group comparisons revealed no significant MTR changes, although there was a trend towards MTR reduction in the left superior temporal gyrus, in the right occipital cortex, and left periventricular white matter in patients compared with controls prior to correction for multiple comparisons (p0.001, uncorrected).MTI and voxel-by-voxel statistical analysis used in the study failed to identify regions of significant MTR reductions in schizophrenic patients. Our results disagree with findings of widespread MTR abnormalities reported in recent literature.

Progress in the treatment of brain neoplasms requires accurate identification of tumor type and grade, before a proper treatment plan can be implemented. The aim of our study was to investigate the use of proton magnetic resonance spectroscopy in the differential diagnosis of neoplastic brain tumors and tumor-like processes.29 patients with ambiguous CT images of brain mass lesions were examined by MRI. 1H MRS was applied in this group as the primary option to improve differential diagnosis. In each case a routine MRI was taken in three orthogonal planes before and after i.v. administration of Gd-DTPA. 1H MRS was performed at 1.5 T using the PRESS (TE 136 ms) and STEAM (TE 20 ms) single voxel spectroscopy techniques. MRS was performed after i.v. administration of Gd-DTPA. The lesion types according to spectral patterns were compared to postoperative pathology or biopsy results.MRS-based diagnosis was consistent with pathology results in all cases of astrocytoma, glioblastoma and meningioma. In two cases distinguishing brain metastases from glioblastomas was difficult because of contamination of the voxel with brain tissue. Three cases of anaplastic oligodendrogliomas were misclassified as glioblastomas. In two cases MR spectra indicating an inflammatory-demyelinating process correlated with biopsy results and clinical course.1HMRS proved to be a useful tool in establishing tumor type and differentiating between neoplastic and large inflammatory tumor-like lesions.