Value of magnetization transfer imaging in judging microchanges lesions in normal-appearing white matter of multiple sclerosis

Abstract

To explore the value of magnetization transfer imaging (MTI) in judging microscopic lesions in normal-appearing white matter of multiple sclerosis (MS). Forty-one patients with brain MS, 17 males and 24 females, aged 13 approximately 65, and 21 healthy people, 8 males and 13 females, aged 18 approximately 57, used as controls underwent magnetic resonance imaging (MRI) using 3D-spoiled grass (3D-SPGR) series, to scan the whole brain with saturated pulses on and off respectively. The signal values were measured directly in the pictures of these 2 series. The formula MTR = (M(0)-MS)/M(0) x 100% was used, where M0 represents the signal value of region of interest with the saturated pulses off, and Ms represents signal value of region of interest with the saturated pulses on, to calculate the MTR value. With reference to T(2)WI imaging, the MTR values of 17 regions of interest (ROI) in the normal-appearing brain white matter, including the white matter of pons, bilateral cerebellar peduncles, knees of internal capsules, splenium and genu of corpus callosum, and the white matter by the anterior horn and posterior horn of lateral ventricle, body of lateral ventricle, and deep in the frontal and parietal lobes, were measured. The average MTR value of the 17 ROI was used to represent the MTR value of the whole normal-appearing brain and used to make comparison with that of the healthy samples statistically. Compared with those of the healthy samples, the average MTR values of each ROI of the MS patients were lower at different degrees. The difference in the MTR values of the white matter of splenium of corpus callosum, and by lateral ventricle and deep in parietal lobe were especially bigger. The MTR value of the whole brain white matter in the healthy persons ranged from 22.76% to 25.42%, with an average value of 23.97%, both significantly higher than those of the MS patients (19.45% to 24.15%, and 22.44% respectively, both P < 0.05). MTI can be used to detect the microchange of normal appearing white matter in MS. MTR is a sensitive indicator to reflect the damage of structure of tissues.