What is Suprameatal triangle?

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 is the clinical significance of Suprameatal triangle?

Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls.

What is mastoid 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 is spine of Henle?

The suprameatal spine is a small spine, immediately below the posterior root of the zygomatic process, situated at the upper and posterior part of the orifice of the external acoustic meatus. It is a projection for attachment of the auricular cartilage.

What is Stylomastoid foramen?

The stylomastoid foramen is a rounded opening at the inferior end of the facial canal. It is located on the inferior surface of the petrous temporal bone, between the base of the styloid process and the mastoid process of the temporal bone.

What are the mastoid air cells?

The mastoid bone, which is full of these air cells, is part of the temporal bone of the skull. The mastoid air cells are thought to protect the delicate structures of the ear, regulate ear pressure and possibly protect the temporal bone during trauma.

Where is mastoid antrum located?

The mastoid antrum is located between the posterosuperior wall of the external canal and middle fossa floor deep to the depression behind the spine of Henle. B, A mastoidectomy has been completed to expose the capsule of the posterior and lateral canals and the tympanic and mastoid facial segments.

What does the mastoid antrum of the temporal bone communicate with?

The mastoid air cells are located posterior to epitympanic recess. They are a collection of air-filled spaces in the mastoid process of the temporal bone. The air cells are contained within a cavity called the mastoid antrum. The mastoid antrum communicates with the middle ear via the aditus to mastoid antrum.

What is a facial ridge?

12. A high facial ridge is defined as having bone overlying the facial nerve that is 2 mm or greater in thickness although lowering the ridge less than this is commonly desired.

Where is zygomatic process?

temporal bone
The zygomatic process is a long arched process, projecting from the lower part of the squamous part of temporal bone.

What nerve does the stylomastoid foramen transmit?

The facial nerve then exits the facial canal (and the cranium) via the stylomastoid foramen. This is an exit located just posterior to the styloid process of the temporal bone.

What nerve passes through stylomastoid foramen?

The facial nerve exits the skull from the stylomastoid foramen and passes obliquely inferiorly and laterally until it enters the parotid gland. The common facial divisions of the nerve are the temporal, zygomatic, buccal, marginal mandibular, and cervical divisions.

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 is 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.

What is the importance of suprameatal triangle?

Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls.

What is the backbone of Shipo 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 Mc Ewan’s triangle, through which an instrument may be pushed into the mastoid antrum.

What are the mastoid air cells?

The mastoid bone, which is full of these air cells, is part of the temporal bone of the skull. The mastoid air cells are thought to protect the delicate structures of the ear, regulate ear pressure and possibly protect the temporal bone during trauma.

What is spine of Henle?

The suprameatal spine is a small spine, immediately below the posterior root of the zygomatic process, situated at the upper and posterior part of the orifice of the external acoustic meatus. It is a projection for attachment of the auricular cartilage.

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 the Omoclavicular triangle?

The subclavian triangle (or supraclavicular triangle, omoclavicular triangle, Ho’s triangle), the smaller division of the posterior triangle, is bounded, above, by the inferior belly of the omohyoideus; below, by the clavicle; its base is formed by the posterior border of the sternocleidomastoideus.

What Fascies can we see in the Omoclavicular triangle?

Omoclavicular (subclavian) triangle

  • the subclavian artery.
  • the inferior part of the external jugular vein,
  • the investing layer of deep cervical fascia which separates the vessels mentioned above,
  • the trunks of the brachial plexus, which may be felt above and behind the triangle.

What is the location of the suprameatal triangle?

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 Mc Ewan’s triangle, through which an instrument may be pushed into the mastoid antrum.

Where is the suprameatal pit in the human body?

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 Mc Ewan ‘s triangle, through which an instrument may be pushed into the mastoid antrum.

What are the surface markings of the head?

—In addition to the bony points already described which can be determined by palpation, the following are utilized for surface markings: Auricular Point. —The center of the orifice of the external acoustic meatus. Preauricular Point. —A point on the posterior root of the zygomatic arch immediately in front of the external acoustic meatus. Asterion.

Which is the base line of the lambdoidal suture?

A line passing through the inferior margin of the orbit and the auricular point is known as Reid’s base line. The lambdoidal suture can be indicated on either side by the upper two-thirds of a line from the lambda to the tip of the mastoid process. The sagittal suture is in the line joining the lambda to the bregma.

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