[Autoimmune Encephalitis/Meningitis]

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Autoimmune encephalitis (AE) diagnosis can be challenging, with less than half of cases showing brain MRI abnormalities.
• Identifying specific MRI patterns is crucial for prompt diagnosis and effective treatment of AE and related neurological conditions.

Purpose of the Study:

• To highlight the diagnostic utility of specific brain MRI findings in autoimmune encephalitis.
• To correlate particular MRI patterns with distinct neurological conditions.

Main Methods:

• Review of MRI findings in autoimmune encephalitis cases.
• Analysis of diffusion-weighted imaging (DWI) and FLAIR sequences for hyperintensity lesions.
• Correlation of lesion locations and patterns with specific diagnoses.

Main Results:

• DWI and FLAIR images commonly show hyperintensity lesions in cortical/subcortical regions, cerebellum, or brainstem.
• Limbic cortex hyperintensity on DWI suggests N-methyl-D-aspartate receptor (NMDAR) encephalitis.
• RA or polychondritis-related meningitis exhibits bright dot or linear signals on convexities on DWI.
• Area postrema syndrome is a characteristic finding in neuromyelitis optica.

Conclusions:

• Specific MRI patterns, particularly on DWI and FLAIR, are valuable for diagnosing autoimmune encephalitis.
• Prompt identification of these MRI signatures facilitates timely and effective therapeutic interventions for various neurological disorders.