The normal facial nerve (CN VII) can demonstrate some enhancement post gadolinium administration in up to 76% of examinations, and in ~70% of cases is asymmetric left-to-right. It has been attributed to the circumneural facial arteriovenous plexus.
Typical sites of enhancement:
- anterior genu (geniculate ganglion)
- posterior genu (between tympanic and mastoid segments)
- some enhancement can also be seen in the tympanic and mastoid segments.
- proximal greater superfical petrosal nerve
No enhancement should be seen in:
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