Diffusion tensor MRI tractography and cognitive impairment in multiple sclerosis

Abstract

Lesions in strategic brain WM tracts contribute to cognitive impairment in MS through a multisystem disconnection syndrome.

Extensive White Matter Dysfunction in Cognitively Impaired Patients with Secondary-Progressive Multiple Sclerosis

“…Our decision to examine patients with SPMS with cognitive impair- ment means that our results are therefore not directly comparable with previous DTI studies of MS and cognition. [8][9][10][11]13,34 However, our data do demonstrate structural differences between patients with SPMS with and without cognitive impairment and provide insight into the diffuse WM tract disturbances that occur with disease progression. Differences between impaired and nonimpaired patients with SPMS may also provide a potential surrogate marker for new therapeutic interventions to forestall the onset of cognitive impairment even in advanced disease.…”

“…Similarly, a recent study that also dichotomized patients according to performance on multiple cognitive tests demonstrated significantly higher EDSS scores in patients with MS with cognitive impairment. 34 It has also been shown that patients with benign MS with cognitive impairment did not significantly differ from patients with SPMS with respect to normalized brain volume, global WML load, or GM mean diffusivity. 35 In contrast, benign patients without cognitive impairment demonstrated significant differences.…”

“…The present cohort of patients with SPMS is relatively well populated (n ϭ 45), but larger DTI studies of cognition in MS have been performed using different analytic approaches (n ϭ 82). 34 It is also possible that fatigue may have impacted the cognitive testing as it was not assessed. In addition, TBSS is a semi-automated technique that relies on a somewhat arbitrary FA threshold of 0.2 to define WM.…”

Hippocampal and Deep Gray Matter Nuclei Atrophy Is Relevant for Explaining Cognitive Impairment in MS: A Multicenter Study

“…2,4,6 GM damage was also variously related to cognitive impairment in these patients. In particular, higher cortical lesion (CL) volume on double inversion recovery (DIR) sequences, 7,8 reduced neocortical and total GM volume, 7,9 and structural abnormalities within strategic GM regions, such as the thalamus, putamen, and hippocampus, were related to the presence and severity of cognitive symptoms.…”

MRI Predicts ALVAL and Tissue Damage in Metal-on-Metal Hip Arthroplasty

“…Sensitivity, specificity, and predictor importance scores were pooled over 10 forests of 10,000 trees for each of the independent outcomes. Random forest analysis has been used previously in MRI research [21]. All inferential analyses were performed using the SAS System for Windows 9.2 (SAS Institute Inc, Cary, NC, USA).…”