R. Galbusera

University Hospital Basel and University of Basel Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research

Author Of 2 Presentations

Imaging Oral Presentation

FC03.03 - Depicting multiple sclerosis pathology at 160μm isotropic resolution by human whole-brain postmortem 3T magnetic resonance imaging

Speakers
Presentation Number
FC03.03
Presentation Topic
Imaging
Lecture Time
13:24 - 13:36

Abstract

Background

Postmortem magnetic resonance imaging (MRI) of formalin-fixed healthy and diseased human brains with ultra-high spatial resolution has the great potential to depict tissue architecture in fine detail, allowing a deeper understanding of pathological processes. Whole-brain imaging is important since it provides neuroanatomic relationships, reference points across distant brain regions, and a comprehensive view of pathologies affecting the brain. However, ultra-high-resolution whole-brain postmortem MRI is challenging and has been so far almost exclusively performed at 7T with specialized hardware.

Objectives

To develop a 3D isotropic 160µm ultra-high-resolution imaging (URI) approach for human whole-brain ex vivo acquisitions on a standard clinical 3T MRI system. To explore the sensitivity and specificity of the approach to specific pathological features of multiple sclerosis (MS).

Methods

A fixed whole human brain from a patient with secondary progressive MS was investigated. Acquisitions were performed on a clinical 3T Siemens Prismafit MRI system with standard hardware components. URI is based on a gradient echo sequence similar to the 7T approach by Edlow et al. 2019. However, it allows to acquire an isotropic 160µm resolution with low hardware demands and to directly reconstruct the image data on the standard 3T MRI system. URI images display a strong, susceptibility-enhanced tissue contrast.

Results

The reconstructed URI images depicted with remarkable quality the diseased human MS brain at 3T field strength. URI allowed to distinguish fine anatomical details such as the subpial molecular layer, the stria of Gennari as well as some intrathalamic nuclei. Additionally, because of the unprecedented spatial resolution and contrast at 3T, URI permitted to easily identify the presence of subpial lesions, detailed features of intracortical lesions such the presence of incomplete/complete iron rims or patterns of iron accumulation in the entire lesion core in both cortical and white matter lesions (CLs/WMLs), lesions affecting the convoluted layers of the cerebellar cortex and nascent submillimetric CLs/WMLs.

Conclusions

URI provides a comprehensive microscopic insight into the whole-human brain at 3T through the micrometric resolution and a tissue-specific, susceptibility-enhanced contrast. We propose URI as an excellent approach to investigate microscopic brain changes of complex pathologies like MS.

Collapse
Biomarkers and Bioinformatics Oral Presentation

PS09.05 - Value of serum neurofilament light chain levels as a biomarker of suboptimal treatment response in MS clinical practice

Abstract

Background

Serum neurofilament light chain (sNfL) reflects neuro-axonal damage and may qualify as a biomarker of suboptimal response to disease modifying therapy (DMT).

Objectives

To investigate the predictive value of sNfL in clinically isolated syndrome (CIS) and relapsing-remitting (RR) MS patients with established DMT for future MS disease activity in the Swiss MS Cohort Study.

Methods

All patients were on DMT for at least 3 months. sNfL was measured 6 or 12-monthly with the NF-light®assay. The association between sNfL and age was modeled using a generalized additive model for location scale and shape. Z-scores (sNfLz) were derived thereof, reflecting the deviation of a patient sNfL value from the mean value of same age healthy controls (n=8865 samples). We used univariable mixed logistic regression models to investigate the association between sNfLz and the occurrence of clinical events (relapses, EDSS worsening [≥1.5 steps if EDSS 0; ≥1.0 if 1.0-5.5 or ≥0.5 if >5.5] in the following year in all patients, and in those fulfilling NEDA-3 criteria (no relapses, EDSS worsening, contrast enhancing or new/enlarging T2 lesions in brain MRI, based on previous year). We combined sNfLz with clinical and MRI measures of MS disease activity in the previous year (EDA-3) in a multivariable mixed logistic regression model for predicting clinical events in the following year.

Results

sNfL was measured in 1062 patients with 5192 longitudinal samples (median age 39.7 yrs; EDSS 2.0; 4.1% CIS, 95.9% RRMS; median follow-up 5 yrs). sNfLz predicted clinical events in the following year (OR 1.21 [95%CI 1.11-1.36], p<0.001, n=4624). This effect increased in magnitude with increasing sNfLz (sNfLz >1: OR 1.41 [95%CI 1.15-1.73], p=0.001; >1.5: OR 1.80 [95%CI 1.43-2.28], p<0.001; >2: OR 2.33 [95%CI 1.74-3.14], p<0.001). Similar results were found for the prediction of future new/enlarging T2 lesions and brain volume loss. In the multivariable model, new/enlarging T2 lesions (OR 1.88 [95%CI 1.13-3.12], p=0.016) and sNfLz>1.5 (OR 2.18 [95%CI 1.21-3.90], p=0.009) predicted future clinical events (n=853), while previous EDSS worsening, previous relapses and current contrast enhancement did not. In NEDA-3 patients, change of sNfLz (per standard deviation) was associated with a 37% increased risk of clinical events in the subsequent year (OR 1.37 [95%CI 1.04-1.78], p=0.025, n=587).

Conclusions

Our data support the value of sNfL levels, beyond the NEDA3 concept, for treatment monitoring in MS clinical practice.

Collapse