Entrance to the mastoid antrum

Entrance to the mastoid antrum
The medial wall and part of the posterior and anterior walls of the right tympanic cavity, lateral view.
Coronal section of right temporal bone.
Latin	aditus ad antrum mastoideum
Gray's	subject #230 1042
Dorlands/Elsevier	a_16/12113263

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

The entrance to the antrum is a large irregular aperture, which leads backward from the epitympanic recess into a considerable air space, named the tympanic or mastoid antrum.

The antrum communicates behind and below with the mastoid air cells, which vary considerably in number, size, and form; the antrum and mastoid air cells are lined by mucous membrane, continuous with that lining the tympanic cavity.

On the medial wall of the entrance to the antrum is a rounded eminence, situated above and behind the prominence of the facial canal; it corresponds with the position of the ampullated ends of the superior and lateral semicircular canals.

See also

• aditus
• mastoid antrum

External links

• Description at umich.edu

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.