Suprameatal triangle

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Bone: 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.
Latin	f. suprameatica
Gray's	subject #34 140
Dorlands / Elsevier	f_15/12377547

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, mastoid fossa, or MacEwen's triangle, through which an instrument may be pushed into the mastoid antrum.
In the adult, the antrum lies approximately 1cm deep to the suprameatal triangle. This is an important landmark when performing a cortical mastoidectomy. The supreameatal triangle lies deep to the cymba conchae. 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 As such, some of the information contained herein may be outdated.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.

v • d • e Bones of head and neck: the cranium of the skull Occipital Squama external (Inion/External occipital protuberance, Nuchal lines) - planes (Occipital, Nuchal) - internal (Cruciform eminence, Internal occipital protuberance, Sagittal sulcus, Internal occipital crest) Lateral parts Condyle (Condyloid fossa, Condylar canal) - Hypoglossal canal - jugular (Jugular process, Jugular tubercle) Basilar part Pharyngeal tubercle Other Foramen magnum Parietal Parietal eminence - Temporal line - Parietal foramen Frontal Squama Frontal suture - Frontal eminence - external (Superciliary arches, Glabella) - foramina (Supraorbital, Cecum) - Zygomatic process - internal (Sagittal sulcus, Frontal crest) Orbital part Ethmoidal notch - Lacrimal fossa - Trochlear fovea - Frontal sinus - Frontonasal duct Temporal Squama Articular tubercle - Suprameatal triangle - Mandibular fossa - Petrotympanic fissure - Zygomatic process Mastoid part Mastoid foramen - Mastoid process (Mastoid cells) - Mastoid notch - Occipital groove - Sigmoid sulcus - Mastoid antrum (Entrance) Petrous part Carotid canal - Facial canal (Hiatus) - Internal auditory meatus - Aqueduct of cochlea - Stylomastoid foramen fossae (Subarcuate fossa, Jugular fossa) - canaliculi (Inferior tympanic, Mastoid) - Styloid process - Petrosquamous suture (note: ossicles in petrous part, but not part of temporal bone) Tympanic part Suprameatal spine Sphenoid Surfaces Superior surface: Sella turcica (Dorsum sellae, Tuberculum sellae, Hypophysial fossa, Posterior clinoid processes) - Ethmoidal spine - Chiasmatic groove - Middle clinoid process - Petrosal process - Clivus Lateral surface: Carotid groove - Sphenoidal lingula Anterior surface: Sphenoidal sinuses Great wings foramina (Rotundum, Ovale, Vesalii, Spinosum) - Spine - Infratemporal crest - Sulcus for auditory tube Small wings Superior orbital fissure - Anterior clinoid process - Optic canal Pterygoid processes fossae (Pterygoid, Scaphoid) - pterygoid plates (Lateral, Medial) - Pterygoid canal - Hamulus Other Body - Sphenoidal conchae Ethmoid Plates Cribriform plate (Crista galli, Olfactory foramina) - Perpendicular plate Surfaces Lateral surface Orbital lamina - Uncinate process Medial surface Superior nasal concha - Superior meatus - Middle nasal concha - Middle meatus Labyrinth Ethmoid sinus - ethmoidal foramina (Posterior, Anterior)