What is suprameatal triangle?
The suprameatal triangle (Macewen, mastoid fossa) is an area between the posterior wall of the external acoustic meatus and the posterior root of the zygomatic process. In this area, an instrument may be pushed into the tympanic antrum.
What structures form Macewen triangle boundaries?
Boundaries of Macewen’s triangle are as follows:
- Superiorly: Suprameatal crest.
- Anterior-inferiorly: Posterior margin of external auditory canal.
- Posteriorly: A tangential line from the posterior canal wall cutting the suprameatal crest.
What is Aditus ear?
56797. Anatomical terminology. The aditus to mastoid antrum (otomastoid foramen or entrance or aperture to the mastoid antrum) is a large irregular cavity that leads backward from the epitympanic recess into a considerable air space named the tympanic or mastoid antrum.
Where are the temporal bones?
The temporal bones are two major bones in the skull, or cranium. They help form the sides and base of the skull, where they protect the temporal lobe of the brain and surround the ear canal. The other major bones in the skull are: the two parietal bones that make up the top of the skull.
What is the tympanic antrum?
The mastoid antrum (plural: mastoid antra) (also known as tympanic antrum or Valsalva antrum) is an air space (up to 1 cm in size) lying posterior to the middle ear and connected to it by a short passageway, the aditus ad antrum.
What type of bone is temporal?
Temporal bones. This is a pair of irregular bones located under each of the parietal bones.
Which bone is anterior to the temporal bone?
There is an anterior projection from the squamous part of the temporal bone, the zygomatic process. This is located on the lower portion of the squamous part. It initially projects laterally, then turns to pass anteriorly to articulate with the temporal process of the zygomatic bone to form the zygomatic arch.