Magnetization transfer ratio in neuro-Beh�et disease

Abstract

The aim of this study was to determine the contribution of magnetization transfer ratios (MTRs) in detecting disease in normal-appearing brain regions of patients with neuro-Behçet (NB) disease. Thirty-two patients with NB disease were assessed. Fifteen healthy volunteers were examined as the control group. Magnetic resonance (MR) imaging of the head was performed without and with magnetization transfer (MT) contrast. Signal intensity measurements were obtained from ten anatomical regions (centrum semiovale, corona radiata, internal capsule, forceps major, forceps minor, thalamus, substantia nigra pars compacta, substantia nigra pars grisea, inferior pons and middle cerebellar peduncle) in both groups. Also measured in the NB group were parenchymal lesions in the brain stem, basal ganglia and cerebral deep white matter. MTR was calculated for each measurement. Statistical analysis was performed with Mann-Whitney U and independent t-tests with computer-based SPSS 11.0 for Windows software. A P value below 0.05 was considered statistically significant. The mean MTR of the parenchymal lesions in the NB group was lower than the mean MTR of the normal-appearing parenchyma in both the NB patients and the normal group. For the normal-appearing parenchyma the mean MTR in the NB group was higher than that for the controls for all regions except the corona radiata; however, the difference was statistically significant only for the thalamus. The MRI-visible parenchymal involvement of Behçet's disease causes a decrease in MTR. For the normal-appearing brain, although lacking statistical significance for the most regions studied, the tendency for higher MTR in NB patients compared with controls may offer an insight into the pathophysiology of Behçet's disease.

Evaluation of Normal Appearing White Matter in Multiple Sclerosis

“…therefore, a low Mt ratio (Mtr) indicates a reduced capacity of the macromolecules in brain tissue to exchange magnetization with the surrounding water molecules, thus possibly reflecting matrix damage to myelin or to the axonal membrane [1,18,19,[35][36][37]. the analysis of MT changes can be performed on a regional basis providing information regarding individual lesions or discrete areas of the NAWM and MTR can be calculate for each ROI based measurement or, on a more global basis, using MTR histograms [30,35]. In this study ROI based measurements were performed changes in myelin content are associated with changes in MT in MS patients [37] and Mtr decreases with acute demyelination and increases with remyelination.…”

Magnetic resonance imaging findings and outcome of neuro‐Behçet's disease: the predictive factors

“…1,2 Magnetic resonance imaging (MRI) is by far the most helpful ancillary investigation for the diagnosis of NBD. Conventional imaging techniques, [3][4][5][6][7][8][9][10][11][12][13] magnetization transfer ratio 14 and MR spectroscopy 15 have been used for the assessment of NBD patients.…”