Differential brainstem atrophy patterns in multiple sclerosis and neuromyelitis optica spectrum disorders

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are inflammatory demyelinating diseases of the central nervous system (CNS).
• Distinguishing MS from NMOSD is crucial due to differing treatments and prognoses.
• Brainstem involvement is a common feature in both MS and NMOSD.

Purpose of the Study:

• To investigate differential patterns of brainstem atrophy using volumetric analysis in MS and NMOSD.
• To determine if these atrophy patterns correlate with clinical disability in MS and NMOSD patients.

Main Methods:

• A case-control cross-sectional study involving 17 MS patients, 13 NMOSD patients, and 18 healthy controls (HC).
• Volumetric measurements of brainstem regions were performed using T1-weighted and T2-weighted spin-echo images acquired on a 3T scanner.
• Statistical analyses included t-tests, Mann-Whitney U-test, partial correlation, and multiple regression analysis.

Main Results:

• MS patients showed significantly reduced normalized whole brainstem, midbrain, and pons volumes compared to HC.
• NMOSD patients exhibited significantly reduced normalized medulla oblongata volume compared to HC.
• Normalized midbrain volume was smaller in MS than NMOSD, while normalized medulla volume was smaller in NMOSD than MS.

Conclusions:

• Distinct patterns of brainstem atrophy differentiate MS and NMOSD.
• MS primarily affects the midbrain and pons, whereas NMOSD predominantly impacts the medulla oblongata.
• Brainstem atrophy, particularly in the pons and medulla oblongata, is associated with increased clinical disability in NMOSD.