Periventricular lesions help differentiate neuromyelitis optica spectrum disorders from multiple sclerosis

Area of Science:

• Neuroimaging
• Radiology
• Neurology

Background:

• Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOsd) are inflammatory demyelinating diseases of the central nervous system.
• Distinguishing between MS and NMOsd is crucial for appropriate treatment and management.
• Periventricular lesions are a common finding in both conditions but may exhibit different characteristics.

Purpose of the Study:

• To compare the imaging characteristics of periventricular lesions in patients with MS and NMOsd.
• To identify specific MRI features that can help differentiate MS from NMOsd.

Main Methods:

• Retrospective analysis of sagittal and axial fluid-attenuated inversion recovery (FLAIR) MRI sequences.
• Evaluation of periventricular lesions by two neuroradiologists in 20 NMOsd and 40 MS patients.
• Characterization of lesion borders (smooth vs. jagged) and presence of "Dawson's fingers".

Main Results:

• Smooth-bordered (Type A) periventricular lesions were found in 80-85% of NMOsd patients versus 5% of MS patients.
• Jagged-bordered (Type B) lesions were observed in 95% of MS patients compared to 15-20% of NMOsd patients.
• Dawson's fingers were present in 77.5-92.5% of MS patients but rarely in NMOsd patients (0-5%).

Conclusions:

• Jagged-bordered periventricular hyperintensities and Dawson's fingers are highly indicative of MS.
• These MRI findings are typically absent in NMOsd, offering a practical method for differential diagnosis.
• MRI lesion morphology plays a key role in distinguishing MS from NMOsd.