Magnetization transfer ratio histogram analysis of gray matter in relapsing-remitting multiple sclerosis

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Multiple sclerosis (MS) is a white matter disease that can affect gray matter.
• Magnetization transfer ratio (MTR) is a sensitive imaging marker for structural abnormalities in MS.
• Previous studies have frequently utilized MTR in MS imaging.

Purpose of the Study:

• To evaluate gray matter MTR in relapsing-remitting MS patients versus healthy controls.
• To assess the correlation between gray matter MTR abnormalities and neurologic disability (EDSS) in MS.
• To investigate the relationship between gray matter MTR and T2 lesion volume in MS.

Main Methods:

• Acquired fast spin-echo dual-echo and magnetization transfer (MT) images from 18 MS patients and 18 controls.
• Segmented gray matter using a semiautomated system.
• Analyzed gray matter MTR histogram parameters, EDSS, T2 lesion volume, and gray matter volumes.

Main Results:

• Significant differences in gray matter MTR (mean and median) were observed between MS patients and healthy subjects.
• Gray matter MTR histogram normalized peak heights inversely correlated with EDSS (r = -0.65, P =.01).
• An inverse correlation was found between mean gray matter MTR and total T2 lesion volume.

Conclusions:

• Gray matter MTR differs significantly in MS patients, indicating MS is a diffuse disease affecting the whole brain.
• Neuronal damage in MS appears to accumulate with increasing T2 lesion volume.
• Gray matter MTR measurement may serve as a useful tool for assessing clinical disability in MS.