The pyramidal eminence is a hollow conical projection upon the posterior wall of the

tympanic cavity The tympanic cavity is a small cavity surrounding the bones of the middle ear. Within it sit the ossicles, three small bones that transmit vibrations used in the detection of sound. Structure On its lateral surface, it abuts the external audit ...

of the

middle ear The middle ear is the portion of the ear medial to the eardrum, and distal to the oval window of the cochlea (of the inner ear). The mammalian middle ear contains three ossicles (malleus, incus, and stapes), which transfer the vibrations ...

. The

stapedius muscle The stapedius is the smallest skeletal muscle Skeletal muscle (commonly referred to as muscle) is one of the three types of vertebrate muscle tissue, the others being cardiac muscle and smooth muscle. They are part of the somatic nervous syste ...

arises in the hollow of the eminence and its tendon exits through its apex. The pyramidal eminence is situated inferior to the aditus to mastoid antrum, immediately inferior to the

oval window The oval window (or ''fenestra vestibuli'' or ''fenestra ovalis'') is a connective tissue membrane-covered opening from the middle ear to the cochlea of the inner ear. Vibrations that contact the tympanic membrane travel through the three ossicl ...

(fenestra vestibuli), and anterior to the vertical portion of the

facial canal The facial canal (also known as the Fallopian canal) is a Z-shaped canal in the temporal bone of the skull. It extends between the internal acoustic meatus and stylomastoid foramen. It transmits the facial nerve (CN VII) (after which it is nam ...

. The apex of the eminence is directed anteriorly toward the oval window. The cavity in the pyramidal eminence is prolonged inferoposteriorly anterior to the facial canal, with which it communicates by a minute aperture which transmits the nerve to the stapedius from the facial nerve (CN VII). The space lateral to the pyramidal eminence is the facial recess, which is accessed during surgery for

cochlear implant A cochlear implant (CI) is a surgically implanted Neuroprosthetics, neuroprosthesis that provides a person who has moderate-to-profound sensorineural hearing loss with sound perception. With the help of therapy, cochlear implants may allow for imp ...

. The space medial to the pyramidal eminence is the sinus tympani.

References

Auditory system {{anatomy-stub