Global brain atrophy and metabolic dysfunction in LGI1 encephalitis: A prospective multimodal MRI study

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Leucin-rich glioma-inactivated 1 protein (LGI1) encephalitis frequently leads to chronic cognitive deficits.
• Understanding the underlying structural and metabolic brain changes is crucial for predicting patient outcomes.

Purpose of the Study:

• To investigate structural and metabolic brain abnormalities in LGI1 encephalitis survivors.
• To correlate these findings with acute and long-term clinical outcomes.

Main Methods:

• Multimodal 3 Tesla MRI, including automated volumetry, diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS), was performed on nine patients.
• Follow-up imaging was conducted 33.1±18 months post-onset and compared to nine healthy controls.

Main Results:

• Diffusion tensor imaging revealed widespread white matter changes in the cerebral and cerebellar regions, particularly in the corona radiata, capsula interna, and corpus callosum.
• Magnetic resonance spectroscopy showed reduced glutamine/glutamate levels in white matter.
• Increased cerebellar gray matter volume correlated with better initial function, while larger putaminal volume was linked to improved cognition at follow-up.

Conclusions:

• Poor clinical outcomes in LGI1 encephalitis are associated with global brain atrophy and white matter tract disintegration.
• Pathological changes extend beyond temporomesial structures to affect frontal lobes and the cerebellum.