Peripheral Nerve Involvement at First Diagnosis of Multiple Sclerosis: A Prospective MR Neurography Study

Area of Science:

• Neuroimaging and Neuroscience
• Peripheral Nervous System Disorders
• Autoimmune Diseases

Background:

• Multiple Sclerosis (MS) is a central nervous system demyelinating disease.
• Peripheral nerve involvement in MS is not fully understood.
• Quantitative Magnetic Resonance (MR) neurography offers potential for assessing peripheral nerves.

Purpose of the Study:

• To evaluate peripheral nerve involvement in newly diagnosed MS patients using quantitative MR neurography.
• To correlate MR neurography findings with clinical, laboratory, electrophysiological, and central nervous system imaging data.
• To assess the diagnostic accuracy of MR biomarkers for peripheral nerve changes in MS.

Main Methods:

• Prospective study of 30 newly diagnosed MS patients and 30 healthy controls.
• High-resolution 3 T MR neurography of tibial and peroneal nerves using T2-relaxometry.
• Analysis of MR biomarkers (T2 relaxation time, proton spin density, nerve cross-sectional area) and correlation with clinical and imaging data.

Main Results:

• MS patients exhibited diffuse peripheral nerve changes: decreased proton spin density (PSD), increased T2 relaxation time (T2 app), and smaller tibial nerve cross-sectional area (CSA).
• Tibial PSD was the most effective biomarker for differentiating MS patients from controls (AUC = 0.876).
• Peripheral nerve changes correlated with intrathecal immunoglobulin synthesis, contrast-enhancing brain/spine lesions, and abnormal electrophysiology.

Conclusions:

• Quantitative MR neurography effectively reveals peripheral nerve alterations in early MS.
• The observed correlations suggest a potential primary affection of the peripheral nervous system in MS.
• MR neurography may serve as a valuable tool for understanding the full spectrum of MS pathology.