Central motor conduction time in progressive multiple sclerosis. Correlations with MRI and disease activity

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Progressive multiple sclerosis (MS) is characterized by neurological decline.
• Spinal cord lesions and demyelination are key pathological features in MS.
• Understanding the relationship between motor pathway dysfunction and MS progression is crucial.

Purpose of the Study:

• To correlate motor conduction time abnormalities with spinal cord MRI lesions in progressive MS.
• To investigate the relationship between changes in motor conduction over time and clinical/MRI changes.
• To explore mechanisms of clinical deterioration in progressive MS.

Main Methods:

• Central motor conduction time (CMCT) measurements were performed at baseline and end-of-study.
• Serial MRI of the brain and spinal cord were conducted monthly for 12 months.
• Clinical evaluations using the Expanded Disability Status Scale were performed monthly for 12 months in 20 progressive MS patients.

Main Results:

• CMCT latencies correlated with disability (tibialis anterior) and cervical spinal cord MRI lesion load/atrophy (upper limb muscles).
• 15 of 19 patients showed clinical deterioration over 12 months.
• Increased motor response latencies were observed only in patients with new spinal cord lesions.

Conclusions:

• Prolonged CMCT is associated with spinal cord lesion burden in progressive MS.
• Changes in CMCT over time are linked to increases in spinal cord lesion load.
• Clinical deterioration in progressive MS may occur independently of new lesions or increased CMCT, potentially due to axonal degeneration.