Otic capsule

Dr Craig Hacking and Dr Henry Knipe et al.

The otic capsule or osseous (bony) labyrinth refers to the dense bone of the petrous temporal bone that surrounds the membranous labyrinth of the inner ear. It is surrounded by the less dense and variably pneumatized petrous apex and mastoid part of the temporal bone.

From anterior to posterior, the osseous labyrinth is comprised of:

It is lined by periosteum. As the membranous labyrinth is slightly smaller than the osseous labyrinth, the two are separate by perilymph, which does not communicate with the endolymph contained in the membranous labyrinth.

There are 4 openings:

Related pathology

Anatomy: Head and neck
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Article information

rID: 40170
System: Head & Neck
Section: Anatomy
Tag: cases
Synonyms or Alternate Spellings:
  • bony labyrinth
  • osseous labyrinth

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Cases and figures

  • Figure 1: otic capsule (blue arrow)
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  • Case 1: PTB fracture involving otic capsule
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