Tympanic cavity

The tympanic cavity is an oblique space between the petrosal and tympanic parts of the temporal bone. It contains the auditory ossicles that transmit vibrations of the tympanic membrane to the perilymphatic space in the inner ear.

The tympanic cavity is divided into the epitympanic recess, the tympanic cavity proper, and occasionally a ventral cavity.

• The epitympanic recess is the smallest of the three areas and is occupied almost entirely by the head of the malleus and incus.

• The tympanic cavity proper is adjacent to the tympanic membrane. On the medial wall of the tympanic cavity proper, there is a bony eminence, the promontory of the petrous portion of the temporal bone, which houses the cochlea.

• The ventral part of tympanic cavity (ventral cavity; fundic part of tympanic cavity) is occupied by the ventromedial portion of the tympanic bulla and separated from the tympanic cavity proper by the septum bullae.