Thalamus volume and ambulation in multiple sclerosis: a cross-sectional study

Area of Science:

• Neuroimaging
• Neurology
• Biomedical Science

Background:

• Multiple Sclerosis (MS) is a chronic neurological disease.
• Ambulation impairment is a common symptom in MS patients.
• Subcortical gray matter (SGM) involvement is increasingly recognized in MS.

Purpose of the Study:

• To investigate if subcortical gray matter (SGM) structures explain differences in timed 25-foot walk (T25FW) speed between MS patients and controls.
• To determine the relationship between SGM volumes, T2 lesion volume (T2LV), and T25FW speed in MS.
• To assess the role of specific SGM structures, particularly the thalamus, in MS-related gait impairment.

Main Methods:

• Cross-sectional study design.
• Brain MRI including 3D T1-weighted imaging for SGM volume calculation (thalamus, caudate, putamen, pallidum).
• Timed 25-foot walk (T25FW) test for gait speed assessment and T2 lesion volume (T2LV) quantification.

Main Results:

• Significant differences in T25FW speed, SGM volumes, and T2LV were observed between MS patients and controls.
• T25FW speed demonstrated associations with SGM volumes and T2LV in both groups.
• Thalamic volume was found to partially mediate the difference in T25FW speed between MS patients and controls.

Conclusions:

• Reduced thalamus volume is a significant factor associated with compromised ambulation in multiple sclerosis.
• SGM integrity, particularly thalamic volume, plays a crucial role in maintaining gait function in MS.
• These findings highlight the importance of subcortical structures in the pathophysiology of MS-related mobility issues.