Morphology-Specific Discrimination between MS White Matter Lesions and Benign White Matter Hyperintensities Using...

Area of Science:

• Neuroimaging
• Radiology
• Neurology

Background:

• North American Imaging in Multiple Sclerosis guidelines recommend a specific radiologic definition for MS white matter (WM) lesions and mimics.
• Accurate differentiation of MS from benign WM lesions is crucial for diagnosis and management.

Purpose of the Study:

• To utilize susceptibility-weighted imaging (SWI) and magnetization-prepared FLAIR images for sensitive differentiation of MS from benign WM lesions.
• To identify specific morphologic characteristics of WM lesions indicative of MS.

Main Methods:

• Seventeen relapsing-remitting MS patients and 18 healthy controls underwent 7T MRI, including FLAIR and multiecho gradient-echo sequences.
• Optimized postprocessing generated single-slice SWI of cerebral veins, which were registered with FLAIR images.
• Three readers assessed lesion morphology, location, and assessment time, analyzing lesions >3 mm, nonconfluent lesions >3 mm, and nonconfluent lesions >3 mm with no or a single central vein.

Main Results:

• The SWI/FLAIR protocol effectively assessed central veins and hypointense rims in WM lesions.
• Nonconfluent lesions with at least one central vein demonstrated the highest specificity and sensitivity for differentiating MS patients from controls.
• A threshold of 67% perivenous WM lesions achieved 94% sensitivity and 100% specificity in separating MS patients from controls.

Conclusions:

• Nonconfluent WM lesions greater than 3 mm with at least one central vein are the most sensitive and specific MRI indicators for distinguishing MS from control subjects.
• This imaging approach aids in establishing a precise radiologic definition for MS WM lesions, aligning with recent guidelines.