Autoimmune encephalitis: what the radiologist needs to know

Area of Science:

• Neurology
• Immunology
• Radiology

Background:

• Autoimmune encephalitis is an immune-mediated central nervous system disorder.
• It was initially described as a paraneoplastic phenomenon but can also occur non-paraneoplastically, affecting limbic and extra-limbic structures.
• The varied clinical presentations, including cognitive, psychiatric, and seizure symptoms, necessitate increased awareness.

Purpose of the Study:

• To highlight the radiological characteristics of autoimmune encephalitis and its subtypes.
• To discuss differential diagnoses for suspected autoimmune encephalitis.
• To propose an optimal imaging work-up, including MRI protocols.

Main Methods:

• Review of radiological findings in autoimmune encephalitis.
• Comparison with alternative diagnoses such as other encephalitides, neoplasms, vascular conditions, and post-seizure alterations.
• Discussion of diagnostic imaging work-up and MRI protocols.

Main Results:

• Autoimmune encephalitis exhibits characteristic limbic and extra-limbic radiological features.
• Radiologists play a key role in suspecting autoimmune encephalitis, prompting further diagnostic evaluation.
• Understanding imaging findings aids in differentiating autoimmune encephalitis from other neurological conditions.

Conclusions:

• Early radiological identification of autoimmune encephalitis is vital for prompt therapeutic intervention and improved prognosis.
• Comprehensive diagnostic work-up, guided by imaging, is essential.
• Awareness of radiological patterns aids in timely diagnosis and management of this complex neurological disorder.