Importance of diffusion weighted magnetic resonance imaging in evaluation of the treatment efficacy in multiple sclerosis patients with acute attacks

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. In addition to clinical improvements, contrast-enhanced MRI is widely used in the evaluation of effectiveness of the treatment during acute MS attacks. However, there are a lot of studies about findings of diffusion-weighted magnetic resonance (DWMR) imaging related to MS in literature, but there is not any study to evaluate effectiveness of patient?s treatment during acute attacks. In this study, we planned to investigate contribution of DWMR to the treatment efficacy with ADC values which were measured in acute and chronic plaque before and after MS treatment. ADC changes in normal appearing white matter (NAWM) in patients with MS and healthy volunteers were also evaluated in this study.25 patients with MS and 30 healthy subjects with normal brain MR findings were included to our study. Contrast enhancement in plaque was evaluated as an acute, and non-contrast enhancement in plaque was evaluated as a chronic. ADC were measured using 3 different b values (b100, b500, b1000 sn/mm2) in 60 acute and 73 chronic plaques before the treatment and repeated remaining 23 acute and 73 chronic plaques after the treatment. Also, ADC measurements were performed using the same parameters in NAWM in plaque neighborhood and volunteers. Results were compared with appropriate statistical methods.ADC values from b100, b500, b1000 in acute and chronic plaques were decreased after the treatment, and these reductions were statistically significant for acute plaques in b500 and for chronic plaques in b500 and b1000. The mean ADC values were measured as 1.53±0.49x10-3 and 1.43±0.58x10-3 in acute plaques and 1.40±0.35x10-3 and 1.34±0.36x10-3 mm2/sec in chronic plaques before and after the treatment, respectively.As a result; we think that DWMR have important role due to quantitative measurement ability in the evaluation of the treatment efficacy of the MS patients with acute attack in addition to contrast-enhanced MR sequence.Key Words: Diffusion-weighted magnetic resonance imaging, magnetic resonance imaging, multiple sclerosis, diffusion-weighted imaging.