The relevance of cortical lesions in patients with multiple sclerosis

Abstract

BackgroundRecent studies suggest that cortical lesions in multiple sclerosis (MS) substantially contribute to clinical disease severity. The present study aimed at investigating clinical, neuroanatomical, and cognitive correlates of these cortical lesions with a novel approach, i.e. by comparing two samples of relapsing-remitting multiple sclerosis (RRMS) patients, one group with and the other without cortical lesions.MethodsHigh-resolution structural MRI was acquired from 42 RRMS patients and 43 controls (HC). The patient group was dichotomized based on the presence versus absence of DIR-hyperintense cortex-involving lesions, resulting in a cortical lesion group (CL, n = 32) and a non-cortical lesion group (nCL, n =10). Cognitive functioning was assessed in all participants with a comprehensive neuropsychological battery, covering mnestic, executive, and attentional functions.ResultsHighest densities of cortical lesions in the CL group were observed in the bilateral parahippocampal gyrus. Relative to HC, patients with cortical lesions - but not those without - showed significant global cortical thinning and mnestic deficits. The two patient groups did not differ from each other regarding demographic and basic disease characteristics such as EDSS scores.ConclusionThe appearance of cortical lesions in MS patients is associated with cortical thinning as well as mnestic deficits, which might be key characteristics of a 'cortically dominant' MS subtype.Electronic supplementary materialThe online version of this article (doi:10.1186/s12883-016-0718-9) contains supplementary material, which is available to authorized users.

Emerging Approaches for Validating and Managing Multiple Sclerosis Relapse

“…Cortical pathology and cognitive dysfunction are typically associated with progressive forms of late stage MS; however, recent studies suggest that gray matter damage begins earlier and can increase the severity and progression of RRMS (8). Historically, cortical demyelinating lesions could not be detected using conventional MRI techniques.…”

“…Although it has not yet been technically possible to perform a corollary analysis of this type in humans, pathological studies have indicated that the presence of these tertiary lymphoid follicles is associated with an increased severity of disease progression (11). Therefore, patients with and without cortical lesions or ectopic follicular structures may represent subpopulations with different disease trajectories, which could influence treatment options (8), and necessitates the development of better detection methods for these features.…”

Gray matter network reorganization in multiple sclerosis from 7‐Tesla and 3‐Tesla MRI data

“…In our study, the most notorious regional group and magnetic field differences appeared in the frontal, cingulate, and temporal cortices. These specific brain regions have been proved to be highly relevant for the clinical and pathological manifestation of MS 36‐38 . Early studies have proposed that the sensitivity of GWc to GM damage can overcome that of CT 19,29 .…”

Cognitive Impairment in Multiple Sclerosis Is Reflected by Increased Susceptibility to the Sound-Induced Flash Illusion

“…Furthermore, extensive cortical damage at the onset of the disease is associated with florid inflammatory clinical activity and predisposes to a rapid occurrence of the progressive phase of MS (32). Moreover, cortical lesions are associated with cognitive and physical disability in MS (33, 34). Thus, MS-related demyelinating of white matter tracts which support the interplay between cortical regions in the healthy brain as well as cortical MS lesions might be the common underpinning of the observed findings: once the common neural pathways are disrupted, both crossmodal information transfer and cognitive processing are diminished.…”