Suprameatal triangle

In the temporal bone, between the posterior wall of the external acoustic meatus and the posterior root of the zygomatic process is the area called the suprameatal triangle, suprameatal pit, mastoid fossa, foveola suprameatica, or Macewen's triangle, through which an instrument may be pushed into the mastoid 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.

Suprameatal triangle
Relations of the brain and middle meningeal artery to the surface of the skull. 1. Nasion. 2. Inion. 3. Lambda. 4. Lateral cerebral fissure. 5. Central sulcus. AA. Reid's base line. B. Point for trephining the anterior branch of the middle meningeal artery. C. 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.
Macewan's suprameatal triangle
Details
Identifiers
Latin	foveola suprameatica
TA98	A02.1.06.069
TA2	710
FMA	54960
Anatomical terms of bone [edit on Wikidata]

References

This article incorporates text in the public domain from page 140 of the 20th edition of Gray's Anatomy (1918)