Assessing Lumbar Plexus and Sciatic Nerve Damage in Relapsing-Remitting Multiple Sclerosis Using Magnetisation...

Area of Science:

• Neuroscience
• Radiology
• Immunology

Background:

• Multiple sclerosis (MS) is increasingly recognized to affect the peripheral nervous system (PNS) alongside the central nervous system (CNS).
• Pathophysiological mechanisms in the PNS include demyelination and axonal degeneration.
• Previous research has primarily focused on CNS involvement in MS.

Purpose of the Study:

• To investigate PNS damage in relapsing-remitting multiple sclerosis (RRMS) at the lumbar plexus and sciatic nerve.
• To utilize magnetisation transfer ratio (MTR) as an imaging biomarker for myelin content alterations in the PNS.
• To compare MTR values between RRMS patients and healthy controls (HCs).

Main Methods:

• Magnetic resonance neurography (MRN) and MTR imaging were employed to assess the lumbar plexus and sciatic nerve.
• 15 RRMS patients and 11 HCs underwent MRI scans and clinical assessments (EDSS).
• Linear regression models analyzed differences in MTR values and their association with EDSS scores.

Main Results:

• Significantly lower MTR values were found in the sciatic nerve of RRMS patients compared to HCs.
• No significant MTR differences were observed in the lumbar plexus between RRMS patients and HCs.
• No correlation was found between PNS MTR measures and Expanded Disability Status Scale (EDSS) scores in the RRMS cohort.

Conclusions:

• This study provides evidence of PNS damage in RRMS patients, specifically in the sciatic nerve.
• The findings suggest demyelination occurring independently at different anatomical locations within the PNS.
• Further research is warranted to confirm these findings and elucidate the underlying pathophysiology.