Falciform crescent

The falciform crescent (or crista falciformis) is a horizontal ridge that divides the internal acoustic meatus into superior and inferior portions.

Superior

The facial nerve and superior vestibular nerve (SVN) travel in the superior portion of the IAM with the facial nerve anterior to the SVN and separated from it in the lateral portion by Bill's bar, a vertical ridge of bone.

Inferior

The cochlear nerve and inferior vestibular nerve (IVN) run inferior to the falciform crescent with the cochlear nerve situated more anteriorly.

Head and neck anatomy
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Article information

rID: 4518
System: Head & Neck
Tag: refs
Synonyms or Alternate Spellings:
  • Crista falciformis

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Cases and figures

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    Fig 1: nerves of the internal acoustic meatus
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