Lesion probability mapping to explain clinical deficits and cognitive performance in multiple sclerosis

Area of Science:

• Neuroimaging
• Neurology
• Multiple Sclerosis Research

Background:

• Lesion dissemination in time and space is a key diagnostic marker for multiple sclerosis (MS).
• The correlation between magnetic resonance imaging (MRI) lesion load and disability in MS is modest.
• Strategic lesion location may explain the 'clinico-radiologic paradox' in MS.

Purpose of the Study:

• To map lesion location probability using a non-parametric permutation-based approach in patients with MS.
• To correlate these lesion probability maps with neurologic and cognitive function assessments.
• To investigate the relationship between specific lesion locations and clinical manifestations in MS.

Main Methods:

• Studied 121 patients with clinically isolated syndrome, relapsing-remitting MS, or secondary progressive MS.
• Utilized T2-weighted MRI to identify MS lesions.
• Employed a non-parametric permutation-based approach for lesion location probability mapping.

Main Results:

• Expanded Disability Status Scale scores correlated with bilateral periventricular lesion location.
• Sensory and coordination deficits correlated with lesions in the thalamus and middle cerebellar peduncle.
• Cognitive deficits, including verbal fluency and spatial recall, showed correlations with specific lesion locations in the parietal, frontal, temporal lobes, and amygdala.

Conclusions:

• Lesion probability mapping supports the association between specific MS lesion locations and symptom development.
• However, specific lesion locations only partially explain the range of cognitive and neurological problems observed in MS patients.