What MRI finding is characteristic of multiple sclerosis plaques?

What MRI finding is characteristic of multiple sclerosis plaques?

• A. Periventricular ovoid demyelinating lesions perpendicular to ventricles (Dawson fingers)
• B. Temporal lobe atrophy
• C. Hippocampal sclerosis
• D. Subcortical lacunar infarcts

Answer: (A)

Multiple sclerosis plaques characteristically form periventricular, ovoid demyelinating lesions that radiate perpendicular to the ventricles—the Dawson fingers pattern. This occurs because inflammation targets small veins in the deep white matter near the ventricles, so the demyelination extends outward from the ventricular surface in a finger-like orientation. On MRI, these lesions are best seen on T2-weighted or FLAIR sequences and often cluster around the ventricles, including the corpus callosum. Other options don’t fit MS: temporal lobe atrophy suggests neurodegenerative processes, hippocampal sclerosis is linked to mesial temporal epilepsy or degeneration, and subcortical lacunar infarcts reflect small-vessel ischemic disease rather than MS-specific periventricular demyelination.

Multiple sclerosis plaques characteristically form periventricular, ovoid demyelinating lesions that radiate perpendicular to the ventricles—the Dawson fingers pattern. This occurs because inflammation targets small veins in the deep white matter near the ventricles, so the demyelination extends outward from the ventricular surface in a finger-like orientation. On MRI, these lesions are best seen on T2-weighted or FLAIR sequences and often cluster around the ventricles, including the corpus callosum. Other options don’t fit MS: temporal lobe atrophy suggests neurodegenerative processes, hippocampal sclerosis is linked to mesial temporal epilepsy or degeneration, and subcortical lacunar infarcts reflect small-vessel ischemic disease rather than MS-specific periventricular demyelination.