Brigham & Women's Hospital
Department of Neurology, Laboratory for Neuroimaging Research

Author Of 1 Presentation

Imaging Oral Presentation

HT05.03 - Presentation 03 - 7T MRI cerebral leptomeningeal enhancement predicts gray and white matter lesion accumulation one year later in relapsing-remitting multiple sclerosis

Speakers
Presentation Number
HT05.03
Presentation Topic
Imaging
Lecture Time
10:39 - 10:51

Abstract

Background

We recently showed that 7T MRI leptomeningeal enhancement (LME) is common in relapsing-remitting multiple sclerosis (RRMS) and is related to gray matter (cortical/thalamic) and white matter (WMLs) lesions.

Objectives

To investigate the dynamics of LME longitudinal change and relationship to subsequent lesion accumulation using 7T MRI.

Methods

25 RRMS subjects [age 44.5±11.2 years (mean±SD), 68% women, Expanded Disability Status Scale (EDSS) 2.0±1.5, 92% on disease-modifying therapy-DMT] and 12 healthy controls (HC) underwent brain 3D MP2RAGE and FLAIR 7T MRI with 0.7 mm3 voxels at baseline and ~1 year. Gadolinium-enhanced 3D-FLAIR was evaluated for LME. WMLs, cortical lesions (CLs) and thalamic lesions (TLs) were expert-quantified. Wilcoxon rank-sum, two-sample t-tests and Spearman’s correlations were investigated.

Results

LME was found in 17/25 (68%) RRMS subjects at baseline and 18/25 (72%) at follow-up vs. a single stable focus in 1/12 HC (8.3%). In the RRMS group, 42 LME foci [mean 2.5±1.1 (range 1-5) per LME+ subject] were identified at baseline versus 48 foci [2.7±1.2 (1-5)] at follow-up. LME foci number at follow-up was unchanged in 18 (72%) RRMS subjects, increased in 6 (24%), decreased in 1 (4%). All 6 subjects with increased LME foci were on treatment [glatiramer acetate, interferon-β (2), rituximab, ocrelizumab, fingolimod]. The subject with LME resolution was treated with ocrelizumab. LME+ subjects had an on-study increase in volume of WMLs (baseline 11.0±14.4 vs. follow-up 12.6±16.3 ml, p<0.001), CLs (0.85±1.2 vs. 1.0±1.4 ml, p=0.002) and TLs (0.103±0.093 vs. 0.117±0.099 ml, p=0.005), whereas LME- subjects had an increase only in WML volume (2.7±2.3 vs. 3.3±2.6 ml, p=0.023). Baseline LME foci number correlated with 1-year change in CL (r=0.36, p=0.078) and WML (r=0.50, p=0.010) volumes. Minimal EDSS change over 1 year was noted. We used these data as the basis for a sample size calculation for a hypothetical trial of a putative therapy that would reduce the rate of MRI lesion accrual by 80% over 1 year. For a single-arm study with 1-year run-in on standard therapy and 1 year on new treatment to achieve 80% power, sample sizes of n=46, n=56 and n=79 were calculated for CL volume, TL volume and LME foci number, respectively.

Conclusions

The evolution of cerebral LME may be a dynamic process in the short term in RRMS, providing a monitoring tool, with about one quarter of patients showing new foci at one year. LME may pose a risk for the subsequent development of new lesions in widespread brain regions, implicating meningeal involvement as a marker or mediator of increased disease severity.

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