الفهرس 
Review
Anatomy of the middle earOnly 14 pages are availabe for public view
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Abstract
The middle ear cleft consists of the tympanic cavity, the Eustachian tube and the mastoid air cell system.
The tympanic cavity contains three ossicles, two muscles, the chorda tympani nerve, and the tympanic plexus .
Both the internal and external carotid arteries supply the tympanic cavity while the anterior tympanic and the stylomastoid arteries are the biggest.
The Eustachian tube is a dynamic channel that links the middle ear with the nasopharynx.
The tensor palati, the salpingopharyngeus, and the levator palati muscles are attached to the Eustachian tube.
The functions of the Eustachian tube are pressure equalization between the middle ear and the atmospheric pressure, mucociliary clearance and protection of the middle ear from nasopharyngeal bacteria and loud noises.
The function of the middle ear is coupling of sound pressures presented at the ear drum to fluid pressures within the cochlea.
The tympanic membrane is formed of outer epidermal, middle fibrous, and inner mucosal layers.
Otitis media with effusion [Glue ear] is defined as chronic inflammation of the middle ear mucosa characterized by the retention of fluid [behind an intact tympanic membrane] within the middle ear space without signs or symptoms of an acute ear infection.
It is highly prevalent during childhood , with more than 50% of children experiencing OME in the first year of life, increasing to more than 60% by 2 years .
The most common complication of OME is hearing loss, and it is the commonest cause of hearing loss in children.
The pathogenesis and risk factors of OME is multifactorial and commonly involves dysfunction of the Eustachian tube, upper respiratory tract infections, impaired mucociliary clearance, allergy (such as Allergic rhinitis), insufficient aeration of the mastoid cells, adenoid disease, immunologic disorders, craniofacial anatomy, secondhand smoke, day care centers, lack of breast-Feeding, bacterial biofilms. Gastroesphageal reflux and laryngopharyngeal reflux (LRR) was recently implicated in the disease pathogenesis of many upper airway and otologic disorders, including OME.