Acute Haemorrhagic Encephalomyelitis (AHEM): MRI Findings

Abstract

Acute disseminated encephalomyelitis (ADEM) comprises a group of demyelinating disorders of the CNS, of which a haemorrhagic variant indicates the most severe clinical course (AHEM). It is supposed to be caused by an overshooting immunological response following an infection or a vaccination. Restricted diffusion of protons could be demonstrated using DW-MRI in a case of rapidly progressive disease with additional haemorrhage. Hence, the addition of DWI adds to the diagnostic power of MRI in the setting of post-infectious demyelinating disorders of the CNS.

Key words

ADEM - MRI - AHEM - DWI

References

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