Author Of 2 Presentations
P0557 - Characterizing 1-year development of cervical cord atrophy across different MS phenotypes: a voxel-wise, multicenter analysis (ID 1115)
In multiple sclerosis (MS) the cervical spinal cord is often affected by demyelination and neuro-axonal injury, leading to irreversible tissue loss.
To use voxel-wise analysis to evaluate the distribution and changes over time of cervical cord atrophy in MS patients from a multicentre dataset acquired at 7 European sites.
Baseline and 1-year 3D T1-weighted cervical cord scans and clinical evaluation were obtained from 54 healthy controls (HC) and 110 MS patients (13 clinically isolated syndromes [CIS], 75 relapsing-remitting [RR] and 22 progressive [P]MS). A pipeline optimized for longitudinal analysis was used to co-register baseline and 1-year follow-up cervical cord scans to a cord template, obtained by averaging straightened HC images from all centers. Voxel-wise differences of cervical cord atrophy, their longitudinal changes and correlations with clinical variables were assessed using SPM12 and full factorial models (sex-, age-, center- and total cord volume-corrected).
Compared to HC, MS patients exhibited significant (p<0.05, family-wise error [FWE] corrected) baseline cervical cord atrophy, mainly located in anterior, posterior and lateral cord regions at C1/C2, as well as in posterior regions between C4 and C6. While CIS patients showed a slight cord tissue expansion vs HC at posterior C4, RRMS presented significant clusters of cord atrophy vs CIS, mostly in lateral and posterior C2-C4 regions, and PMS showed widespread cord atrophy vs RRMS patients at C4-C5 and C7 levels. During the follow-up, a significant progression (p<0.05, FWE) of cord atrophy was detected in MS patients, predominantly in the posterior and lateral cord at C2, and between C4 and C6. Such pattern of cord atrophy progression was mainly driven by RRMS patients, while CIS patients did not show cord tissue loss at follow-up vs baseline, and PMS patients showed circumscribed tissue loss in posterior regions at C2 and C6. A strong relationship (p<0.05, FWE) was found between baseline clinical disability and baseline cord atrophy in the posterior and lateral cord at C2-C4. Also, baseline atrophy in the lateral cord at C3-C4 correlated with clinical disability at 1-year follow-up.
Voxel-wise analysis of cervical atrophy allowed to detect a differential involvement of cord levels and to characterize 1-year evolution of tissue loss across phenotypes. Cord atrophy was clinically relevant and contributed to explain follow-up clinical disability.
P0610 - Multiparametric MRI investigation of enlarging and shrinking MS lesions (ID 1876)
Background: After cessation of contrast enhancement MS lesions may show enlargement or shrinkage on T1w MRI. The presence of hypointense lesion rims on susceptibility weighted MRI may be associated with ongoing inflammation and tissue damage/rearrangement. The relationship of enlarging and shrinking MS lesions on T1w MRI to hypointense rims on SWI is therefore of interest.
Objective: To investigate enlarging and shrinking non-enhancing multiple sclerosis (MS) lesion characteristics using a novel multimodal magnetic resonance imaging (MRI) approach.
Methods: Two high-resolution 3 D T1-weighted 3T MRI datasets obtained 12 months apart were analyzed in 67 MS patients. Non-enhancing enlarging and shrinking lesions were identified by voxel guided morphometry (VGM) demonstrating regional volume changes as compared to stable lesions without volume change. In addition the presence of hypointense lesion rims on susceptibility-weighted imaging (SWI) was evaluated. In order to estimate tissue damage within lesions, T1 signal intensity (SI) ratios and the apparent diffusion coefficient (ADC) were analyzed.
Results: Forty-three patients demonstrated chronic enlarging and/or shrinking lesions (active T1 lesions), while in 24 patients exclusively stable lesions were seen. Overall, we identified 444 chronic MS lesions (109 enlarging, 67 shrinking, 268 stable lesions). Chronic-enlarging/shrinking lesions were more frequently associated with hypointense rims compared to stable lesions (p < 0.05). Both, chronic-enlarging/shrinking lesions showed a stronger decrease of the T1 SI ratio and, conversely, an increase in ADC values at follow-up in comparison to stable lesions. Patients with enlarging or shrinking lesions had longer disease durations, higher EDSS scores, larger T2 lesion volumes and lower normalized brain volumes than patients without such lesions (p < 0.05).
Conclusion: Enlarging and shrinking lesions on T1w MRI frequently show hypointense rims on SWI. Those lesions are linked to progressive white matter damage and may indicate sustained inflammation and may therefore indicate low grade inflammatory changes, that could be a valuable marker of disease activity.