Natalizumab Treatment for Relapsing Multiple Sclerosis Stabilises Normal-Appearing White Matter Microstructure: A...

Area of Science:

• Neuroimaging
• Neurology
• Biomedical Engineering

Background:

• Natalizumab effectively reduces relapses and inflammatory activity in multiple sclerosis (MS).
• Chemical exchange saturation transfer (CEST) MRI offers high-resolution, sensitive in vivo brain tissue analysis.
• Ultra-high field (7 Tesla) MRI enables detailed investigation of brain microstructural changes.

Purpose of the Study:

• To assess if natalizumab prevents microstructural tissue damage progression in normal-appearing white matter (NAWM) using 7 Tesla MRI over one year.
• To investigate natalizumab's effects on tissue microstructure in patients with active relapsing-remitting MS.
• To evaluate microstructural changes using quantitative MRI sequences sensitive to magnetisation transfer (MT) effects.

Main Methods:

• A one-year prospective longitudinal study involving patients with active relapsing-remitting MS.
• Clinical assessments and ultra-high field (7 Tesla) MRI scans at baseline, 6 months, and 12 months post-natalizumab infusion.
• Quantitative imaging included sequences for magnetisation transfer (MT) effects: amide proton transfer (MTRAPT) and nuclear Overhauser effect (MTRNOE).

Main Results:

• No significant difference in T1 relaxation times at 6 and 12 months, indicating no accumulated tissue damage.
• Improvements in MTR (MTRAPT and MTRNOE) at 12 months suggest a tissue repair effect.
• Clinical and conventional MRI measures showed expected lack of worsening in disease activity.

Conclusions:

• Natalizumab effectively prevents microstructural brain damage in MS patients during the first year of treatment.
• Ultra-high field MRI reveals that natalizumab promotes improved white matter microstructure.
• The findings support natalizumab's role in mitigating neurodegenerative processes in MS.