Cognitive deficits in multiple sclerosis: correlations with T2 changes in normal appearing brain tissue.

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Multiple sclerosis (MS) disease load is typically assessed using T2 lesion volumes.
• Changes in T2 relaxation times within normal-appearing brain tissue (NABT) in MS are often overlooked.
• Cognitive impairment is a significant challenge for MS patients, impacting quality of life.

Purpose of the Study:

• To investigate whether T2 changes in NABT correlate with cognitive impairment in MS.
• To determine if NABT T2 changes supplement traditional T2 lesion volume measurements in assessing MS impact.
• To explore the relationship between MR-detected T2 changes and clinical outcomes in MS patients.

Main Methods:

• Retrospective analysis of magnetic resonance (MR) imaging data from 50 patients with clinically definite MS.
• Neuropsychological testing across eight cognitive domains.
• Voxel-wise T2 estimates and total T2 lesion volume correlated with cognitive dysfunction factor (CDF), MSIS, and EDSS scores.

Main Results:

• Distinct clusters of voxels in NABT showed T2 estimates correlating with cognitive dysfunction, processing speed, verbal fluency, and MSIS.
• Total lesion volume negatively correlated with cognitive dysfunction, verbal intelligence, processing speed, visual problem solving, and complex motor speed.
• No significant correlation was found between total lesion load and clinical measures EDSS and MSIS.

Conclusions:

• MR imaging detects T2 changes in NABT in MS patients, suggesting underlying pathology.
• These NABT T2 changes are associated with cognitive impairment in MS.
• NABT T2 changes may serve as a valuable supplement to lesion volume in understanding MS-related cognitive deficits.