Tympanic antrum

Mastoid antrum
Coronal section of right temporal bone. ("Tympanic antrum" labeled at upper left.)
The medial wall and part of the posterior and anterior walls of the right tympanic cavity, lateral view. ("Mastoid antrum" labeled at upper left, in dark circle.)
Details
Identifiers
Latin	antrum mastoideum
Dorlands /Elsevier	a_50/12143566
TA	A15.3.02.028
FMA	55711
Anatomical terms of bone []

The mastoid antrum (tympanic antrum, antrum mastoideum, Valsalva's antrum) is an air space in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells and anteriorly with the epitympanic recess of the middle ear via the aditus to mastoid antrum (entrance to the mastoid antrum). These air spaces function as sound receptors, provide voice resonance, act as acoustic insulation and dissipation, provide protection from physical damage and reduce the mass of the cranium.

The mastoid air cell system is a major contributor to middle ear inflammatory diseases.

Left temporal bone showing surface markings for the tympanic antrum (red), transverse sinus (blue), and facial nerve (yellow).