The sinus tympani (ST) is a critical anatomic region of the temporal bone. It lies medial to the facial nerve, between the ponticulus and the subiculum, and therefore is not easily visualized by routine surgical approaches to the middle ear and mastoid.

Where is sinus tympani?

The sinus tympani is located on the medial wall of the tympanum between the subiculum and the ponticulus. It extends in a posterior direction, medial to the pyramidal eminence, stapedius muscle, and facial nerve and lateral to the posterior semicircular canal.

What is Retrotympanum?

Retrotympanic Spaces. The retrotympanum is a complex structure consisting in different spaces lying in the posterior aspect of the tympanic cavity. Different Authors studied this particularly anatomical region because microscopic view alone is inadequate to explore these posterior spaces.

What is middle ear cleft?

Definition: The middle ear cleft is a space which consists of the middle ear cavity or tympanic cavity, the Eustachian tube, the mastoid air cell system and the mucosal lining the system.

What is processus Cochleariformis?

The processus cochleariformis is a spoon-shaped bony angular process above the promontory at he end of the canal for the tensor tympany and at the anterior end of the vestibular window, forming a pulley over which the tendon of the tensor tympani muscle plays.

What are the types of sinuses?

• The ethmoidal sinuses are located between your eyes.
• The maxillary sinuses are located below your eyes.
• The sphenoidal sinuses are located behind your eyes.
• The frontal sinuses are located above your eyes.

What is sinus plate?

Sigmoid sinus dehiscence, also known as sigmoid plate dehiscence, refers to a defect in the sigmoid plate such that the sigmoid sinus is not separated by bone from the air in the mastoid air cells.

Where is the mastoid antrum?

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 is Jacobson nerve?

Jacobson’s nerve is a tympanic branch of the glossopharyngeal nerve, arising from its inferior ganglion. It enters the middle ear cavity through the inferior tympanic canaliculus, runs in a canal on the cochlear promontory and provides the main sensory innervation to the mucosa of the mesotympanum and Eustachian tube.

What is meatus of ear?

Anatomical terminology The ear canal (external acoustic meatus, external auditory meatus, EAM) is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the pinna to the eardrum and is about 2.5 centimetres (1 in) in length and 0.7 centimetres (0.3 in) in diameter.

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What is Mesotympanum?

[mes″o-tim´pah-num] the portion of the middle ear medial to the tympanic membrane.

How can I see my middle ear?

The otoscope can “see” the tympanic membrane (eardrum) which separates the external ear from the middle ear. Because the eardrum is thin and translucent, it is possible to see some of the structures of the middle ear.

What is pyramidal eminence?

The pyramidal process or eminence of the petrous temporal bone is a small hollow anterior osseous protrusion from the posterior wall of the mesotympanum that separates the sinus tympani medially from the facial recess laterally.

What is chorda?

53228. Anatomical terms of neuroanatomy. The chorda tympani is a branch of the facial nerve that originates from the taste buds in the front of the tongue, runs through the middle ear, and carries taste messages to the brain.

What is the vestibular window?

a circumscribed opening in a plane surface; called also fenestra. … oval window an oval opening in the inner wall of the middle ear, which is closed by the stapes; called also vestibular window and fenestra vestibuli.

What is Stapedius muscle?

The stapedius muscle is the smallest striped muscle of the human body and contracts reflexive in response to acoustic stimulation. The stapedius muscle puls the neck of the stapes in the direction of the stapedius tendon.

What is sinus problem?

When you have a sinus infection, one or more of your sinuses becomes inflamed and fluid builds up, causing congestion and runny nose. View Larger. When you have a sinus infection, one or more of your sinuses becomes inflamed and fluid builds up, causing congestion and runny nose.

What is dehiscence of sinus?

A dehiscence over the sigmoid sinus means there is no bone over the sinus in the area of the dehiscence. A diverticulum is an abnormal outpouching or protrusion of the sinus. A diverticulum may occur in an area of weakness in the wall of the sinus.

What is meant by sigmoid sinus?

The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the pars sigmoid, are venous sinuses within the skull that receive blood from posterior dural venous sinus veins.

What causes sinus problems?

Sinusitis is usually caused by a virus and often lasts even after other upper respiratory symptoms are gone. In some cases, bacteria — or, rarely, fungus — may cause a sinus infection. Other conditions such as allergies, nasal polyps, and tooth infections can also contribute to sinus pain and symptoms.

How do I clear my sinuses?

1. Use a humidifier or vaporizer.
2. Take long showers or breathe in steam from a pot of warm (but not too hot) water.
3. Drink lots of fluids. …
4. Use a nasal saline spray. …
5. Try a Neti pot, nasal irrigator, or bulb syringe. …
6. Place a warm, wet towel on your face. …
7. Prop yourself up. …
8. Avoid chlorinated pools.

What are the four sinuses?

Four sets of paired sinuses are recognized: maxillary, frontal, sphenoid, and ethmoid (see the image below).

What nerves supply ears?

Anatomy of the ear is shown below. Anatomy of the ear. Four sensory nerves supply the external ear: (1) greater auricular nerve, (2) lesser occipital nerve, (3) auricular branch of the vagus nerve, and (4) auriculotemporal nerve.

What does the facial nerve supply?

The facial nerve provides motor innervation of facial muscles that are responsible for facial expression, parasympathetic innervation of the glands of the oral cavity and the lacrimal gland, and sensory innervation of the anterior two-thirds of the tongue.

Where does the tympanic nerve come from?

The tympanic nerve arises from the inferior ganglion of the glossopharyngeal nerve traversing through the tympanic canaliculus into the middle ear. On the promontory it coalesces with sympathetic fibres from the carotid chain forming the tympanic plexus.

Is mastoid antrum present at birth?

In a histologic study of the temporal bones of newborns, conducted by Valtonen and Karmody, the mastoid antrum was noted to be present in all subjects, without significant differences for age, gender, or laterality (right versus left).

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 ear attic?

In human ear: Middle-ear cavity. The cavity of the middle ear is a narrow air-filled space. A slight constriction divides it into an upper and a lower chamber, the tympanum (tympanic cavity) proper below and the epitympanum above. These chambers are also referred to as the atrium and the attic, respectively.

What is the function of the meatus?

The middle meatus is the nasal passageway that lies between the inferior meatus and the middle meatus. This space is important for: Drainage of three of the paranasal sinuses; the maxillary, frontal, and front (anterior) ethmoid sinuses. Airflow through the paranasal sinuses which creates the tones of our voices.

What is an ear hole called?

external auditory canal, also called external auditory meatus, or external acoustic meatus, passageway that leads from the outside of the head to the tympanic membrane, or eardrum membrane, of each ear. The structure of the external auditory canal is the same in all mammals.

What are the ear muscles?

There are two muscles within the middle ear that function to protect it from loud noses — the Tensor Tympani and the Stapedius. Cartoon of the middle ear showing muscles that attach to ossicles (ear bones), and ear drum.