The contribution of MRI in assessing cognitive impairment in multiple sclerosis
Cognitive impairment affects a large proportion of patients with multiple sclerosis (MS) and has a profound impact on their daily-life activities. Improving the knowledge of the pathophysiology of cognitive impairment in MS and of the mechanisms responsible for its evolution over time might contribute to development of better outcome measures and targets for innovative treatment strategies. Due to their ability to detect MS-related abnormalities, MRI techniques are a valuable tool to achieve
... se goals. Following an updated overview of the assessment methods and profile of cognitive impairment in patients with MS, this review provides a state-of-the-art summary of the main results obtained from the application of conventional and modern magnetic resonancebased techniques to quantify MS-related damage, in terms of macroscopic lesions, as well as involvement of the normal-appearing white matter and gray matter and their association with cognitive impairment. The possible role of brain cortical reorganization in limiting the clinical consequences of disease-related damage is also discussed. Finally, the utility of the previous techniques to monitor the progression of cognitive deficits over time and the efficacy of possible therapeutic strategies is considered. Neurology ® 2010;75:2121-2128 GLOSSARY AChEI ϭ acetylcholinesterase inhibitor; BMS ϭ benign multiple sclerosis; BRNB ϭ Brief Repeatable Neuropsychological Battery; CC ϭ corpus callosum; CIS ϭ clinically isolated syndrome; DIR ϭ double inversion recovery; DT ϭ diffusion tensor; FA ϭ fractional anisotropy; GM ϭ gray matter; 1 H-MRS ϭ proton MR spectroscopy; IFN ϭ interferon; MACFIMS ϭ Minimal Assessment of Cognitive Function in Multiple Sclerosis; MD ϭ mean diffusivity; MR ϭ magnetic resonance; MS ϭ multiple sclerosis; MSFC ϭ Multiple Sclerosis Functional Composite; MT ϭ magnetization transfer; MTR ϭ magnetization transfer ratio; NA ϭ normal-appearing; NAA ϭ N-acetylaspartate; PASAT ϭ Paced Auditory Serial Addition Task; RR ϭ relapsingremitting; SDMT ϭ Symbol Digit Modalities Test; SLF ϭ superior longitudinal fasciculus; SP ϭ secondary progressive; WM ϭ white matter.