OTITIS MEDIA

The most important disease of the middle ear and mastoid are inflammations of various kinds and hearing loses. Tumors of the middle ear are rare . In this chapter we'll mainly discussed acute suppurative otitis media (ASOM) and chronic suppurative otitis media (CSOM)

ASOM

Acute suppurative otitis media is one of the most common infections of childhood. It may accompany any upper respiratory tract infection such as the common cold, measles, scarlet fever, or influenza. When virulent bacteria invade the middle ear, an acute suppuration occurs.

Bacteriology

The haemolytic streptococcus, staphylococcus or the pneumococcus are most commonly responsible for the infection.

Infection route

①Bacteria or virus via the pharyngotympanic tube into middle ear is the maximum incidence in childhood.

②Infection via the external meatus is liable to occur when a tympanic membrance perforation is present.

③otitis media arising as a blood-borne infection is rare.

Pathology

1.tubal occlusion;2.presuppuration;3.suppuration;4.resolution.

severe, deep throbbing pain in the ear is the cardinal symptoms;

temperature elevation (more in infants or children)

hearing loss, dizziness, nausea, tinnitus Purulence (a mixture of blood and pus)

symptoms

Signs

examination shows the tympanic membrance is thick, red, and dull. If rupture has occurred, pus and the perforation may be seen.

conductive hearing loss. there is usually pain during

pressure over the mastoid antrum.

Differential Diagnosis external otitis or furunculosi

s of external auditory meatus: postauricular tenderness.

bullous myringitis: the earache may be intense but deafness only slight, the membrane may be obscured by a large haemorrhagic bleb or blebs.

Treatment

1.Antibiotics should be given in full dosage. Penicillin is the drug of choice for empirical selection, except when the patient is sensitive to this drug. In any case, antibiotic sensitivity studies are important. When sensitivity to penicillin is known to exist, erythromycin, or broad-spectrum antibiotics may be used.

2.ear drops: ① pre-rupture, 2%phenol glycerine; ②after rupture, antibiotics solution such

as : 0.25%chloromycetin solution, 0.3%ofloxacin solution.

3.myringotomy is indicated when there is bulging of the drumhead and pain not quickly relived by antibiotics. Myringotomy is usually performed to drain pus from the ear in patients with ASOM or to release serum from the middle ear in patients with secretory media.

CSOM OR COM Neglected or recurrent infection of the middle ear may

eventually produce a chronic change in the mucosa of the ear or destruction of the periosteum covering the ossicles, The infection then tends to become chronic. Chronic infection of the middle ear is much more common in persons who had ear disease in early children. Disease of the ear in infancy and early children may arrest the normal pneumatization of the mastoid. It is possible that the same process alters the mucosa of the middle ear, so that it is more susceptible to recurrent infection than is the normal ear.

Aetiology and pathology

1.Bacteriology: characteristic of the bacteriology of chronic otitis media is a shift towards a predominance of gram-negative bacilli, most frequently isolated bacteria include Pseudomonas aeruginosa, staphylococcus, proteus and corynebacterium.

2.It is also known that chronic infection occurs predominantly in nonpneumatizd clefts. Here it must be said that there is a difference opinion, some authorities holding that failed pneumatization is a result of infection and not a precondition.

3.The prevalence of CSOM is related to social conditions.

4.Although a cholesteatoma may form and gradually enlarge without contamination, it is more common for infection early to supervene upon a pre-existent cholesteatoma, or for a cholesteatoma to form as a result of infectin.

Cholesteatoma

Histologically, cholesteatoma are of two types, epidermoid cholesteatoma and cholesterol granuloma.

epidermoid cholesteatoma epidermoid cholesteatoma is a

bag-like cystic structure lined by keratinizing stratified squamous epithelium resting on a fibrous stroma of variable thickness. epidermoid cholesteatoma is a by-product of keratinizing squamous epithelium .

cholesterol granuloma cholesterol granuloma is a granu

lomatous structure formed by variable numbers of cholesterol crystals, sometimes with haemosiderin, surrounded by foreign body giant cells, and embeded in fresh granulation tissue. cholesterol granuloma results from deposition of cholesterol at a site of suppuration or haemorrhage, and is often associated with a blue drum.

Congenital cholesteatoma A congenital cholesteatoma is aetiol

ogically unconnected with chronic suppurative otitis and is generally anatomically unconnected with the middle ear cleft. It arises in an embryonic cell rest in any of the cranial bones and may remain undetected for years. If it arise in the temporal bone, i.e. petrous pyramaid, it may, by extension, make anatomical connection with the middle ear cleft and become infected therefrom..

Primary acquired cholesteatoma

Primary acquired cholesteatoma refers to those tumors arising without a previous otitis media

Genesis of primary acquired cholesteatoma

Obstruticed attic by embryonic remnants

Negative attic pressure

membrane Invagination

Embryonic cell rest Normal pavement

epithelium

Subclinnical infection added

epithelial metaplasia

Squamous epitheliumin middle ear

cholesteatoma

Tubal occlusion

secondary acquired cholesteatoma

while secondary acquired cholesteatoma occurs in ears known to been the seat of a previous infection, or to be currently infected.

Genesis of secondary acquired cholesteatoma

if a previous acute otitis media has resulted in necrosis of the tympanic membrane and of middle ear mucosa there may be a tendency, especially if the perforation is marginal, for squamous epithelium to migrate into the middle ear from the external meatus. Especially, if a marginal perforation or attic perforation exists, the alternating processes of healing and degeneration may result in the advance of squamous epithelium into the middle.

Signs and symptoms The principal symptom of com is purulent otorrhoea,

while the principal sign is the observation of pus coming from the middle ear via a perforation. Otorrhoea may have been proceeding for years before the patient seeks advice.

Conductive deafness is inevitable in com; Increase smell or blood-staining, polypus at the m

eatus, pain, vertigo, or headache, that often brings the patients to the doctor, and not infrequently these symptoms are indicative of complication requiring urgent surgical intervention.

The safe ear(benign com) and unsafe ear(dangerous com)

safe ear unsafe ear

disease area tubotympanic attic-antrum perforation anterior or central attic or marginal pus mucoid, odourless, profuse thick, fetid, scanty granulations uncommon common polypus if present, usually pale, usually hyperaemic, oedematous fleshy deafness conductive, usually conductive or mixed, slight to moderate moderate to severe cholesteatoma uncommon common

Diagnosis

Signs and symptomsCT or X-ray film

Treatment

Treatment has two main objectives; first to arrest disease, and second to secure conditions that will permit return of tissues to normal or that will allow recovery of function. It is, a general ideal of treatment to secure these objectives by medical, if possible, in preference to surgical means.

Medical treatment

Topical antibiotic application: ① 0.25%chloromycetin solution ② 0.3%ofloxacin solution ③ 4%bonic acid alcohol aural toilet is an essential precursor to any

topical application, ear drops should be applied by the displacement method.

Surgical treatment

Primary objects of operative treatment: ① to render the patient safe ② to prevent further deterioration of function

operation methods

cortical mastoidectomy(simple mastoidectomy, Schwartze opration)

classical radical mastoidectomy modified radical mastoidectomy, attic-antros

tomy anterior tympanotomy combined-approach mastoidectomy posterior tympanotomy

reconstructive surgery

myringoplastyossiculoplastytympanoplasty

tympanoplasty

tympanoplasty without mastoidectomy (Closed technique)

tympanoplasty with mastoidectomy (Opened technique)

思考题

慢性化脓性中耳炎的临床分型及特点

Reference book

Textbook of otolaryngology David d. decease, MD sixth edith

Disease of the ear Stuart R. mawson fourth edith

The end

Thank you

分泌性中耳炎 （ secretory otitis media SOM ）

分泌性中耳炎是以鼓室积液及传导性聋为主要特征的中耳非化脓性疾病。又名卡他性中耳炎等。可分为急、慢性两种，为小儿常见病。

病因

总之是尚未完全明确。可能病因有： 1 、咽鼓管功能障碍 2 、感染 3 、免疫反应

临床表现

1 、症状：听力减退，耳痛，耳鸣 2 、检查：鼓膜改变。电测听为传导性聋，声阻抗

示 B 或 C 型鼓室导抗图

鉴别诊断

1 、胆固醇肉芽肿，颈静脉球体瘤 2 、脑脊液耳漏 3 、鼻咽肿瘤

治疗

1 、清除积液，改善通气引流： ① 鼓膜穿刺抽液 ②鼓膜切开冲洗 (Myringotomy)

③ 鼓室置管术 (Gromnet insertion) 2 、积极治疗原发疾病：鼻及鼻咽疾病等 3 、药物治疗 ： ① 抗生素 ②激素 ③沐舒坦等

思考题 分泌性中耳炎的临床表现及诊断

参考书 耳鼻咽喉科学 第五版 田勇泉主编