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.
Which structure lies deep to suprameatal triangle?
the antrum
In the adult, the antrum lies approximately 1.5 to 2 cm deep to the suprameatal triangle. This is an important landmark when performing a cortical mastoidectomy. The triangle lies deep to the cymba conchae.
What does mastoid antrum mean?
n. A cavity in the petrous portion of the temporal bone that communicates with the mastoid sinuses and epitympanic recess of the middle ear.
What is mastoid fossa?
The tegmen mastoideum forms part of the floor of the middle cranial fossa, separating the mastoid from the cranial cavity. The lateral extracranial surface of the mastoid is sometimes called the mastoid cortex. The anterior landmark is the MacEwen triangle including the spine of Henle.
Suprameatal triangle. D. Sigmoid bend of the transverse sinus. E. Point for trephining over the straight portion of the transverse sinus, exposing dura mater of both cerebrum and cerebellum. Outline of cerebral hemisphere indicated in blue; course of middle meningeal artery in red.
What is the most common type of suprameatal spine?
The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%).
What is the MacEwen triangle in dentistry?
MacEwen triangle. The MacEwen triangle (also called the suprameatal triangle or mastoid fossa) is a surgical landmark on the surface of the temporal bone just superior to the external auditory canal used to locate the level of the mastoid antrum. Three lines form the triangle: