Falciform crescent

Dr Jeremy Jones et al.

The falciform crescent 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
Share article

Article Information

rID: 4518
System: Head & Neck
Section: Anatomy
Tag: refs
Synonyms or Alternate Spellings:

Support Radiopaedia and see fewer ads

Cases and Figures

  • Drag
    Nerves of the internal acoustic meatus (diagram)
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.