Upload
asmaa
View
118
Download
2
Tags:
Embed Size (px)
Citation preview
Supervised by:
Dr. Ahmed Mehana
Presented by:
Asmaa Hassan 193
MIDDLE EAR CLEFT CONSIST OF :
a- the middle ear cavity(tympanic cavity)
b-the Eustachian tube
c- the mastoid air cells
A-THE MIDDLE EAR CAVITY (TYMPANIC CAVITY)
It contains:
Three bones (auditory ossicles)
Two nerves
Two muscles
Walls of middle ear cavity The middle ear is a six wall cavity
B-THE EUSTACHIAN TUBE (THE AUDITORY TUBE)
1- communicates the middle ear cavity with the nasopharynx 2-The tube is shorter, wider, and more horizontal in children than in adults3-. It opens during swallowing and yawing to ventilate the
middle ear.
C -THE MASTOID AIR CELLS -they are located within the mastoid process of the temporal
bone -The largest air cell is the mastoid antrum, which lies behind
the attic
Functions of the middle Ear1- Middle ear collects the sound waves from the outer ear in
the form of pressure waves. The middle ear is involved in transmitting sound from the outer ear to the inner ear.
2- The Eustachian tube functions to equalize air pressure of the eardrum
Otitis mediaWhat is otitis media?
Otitis media is an inflammation of the mucoperiosteal lining of the middle ear cleft
( eustichian tube,tympanic cavity,mastoid antrum and air cell)
Incidence:
they are most common in infants and young children. For the following causes:
A- a child's eustachian tubes are narrower and shorter than an adults', and it's easier for fluid to get trapped in the middle ear.
B- Blockage of the eustachian tubes may be caused by:
• Respiratory infection (cold)• Allergies• Exposure to cigarette smoke• Infected or overgrown adenoids (tonsils)• For infants, being fed lying down (drinking a bottle while lying on
the back)
MicrobiologyThe infection is initially commonly viral in originLater the middle ear mucosa becomes secondarily infected by
pathogenic bacteria. The bacteria commonly implicated in this disorder is :
A-Streptococcus pneumoniaeB-Haemophilus influenzae. C-Moraxella catarrhalis.
Pathogenesis:
Functions of Eustachian tube:a-Equalize pressure between the middle ear and
atmosphere-middle ear pressure slightly negative normally
b-protect the middle ear from nasopharyngeal secretions and sounds
C-drainage of secretions from the middle ear into the nasopharynx
Eustachian tube obstruction leads to negative pressure within
the middle ear ...Obstruction may be due to:
a-intrinsic narrowing
b- functional obstruction
C- Extrinsic obstruction
Flask model explaining the role of eustachean tube in middle ear infections
1-The mouth of the flask represents the nasopharyngeal end
2-the narrow neck, the isthmus of the Eustachian tube,
3-the bulbous portion, the middle ear and mastoid air chamber .
The fluid flow through the neck of the flask would bedependent on the pressure at either end, the radius and length of the neck, and the viscosity of the liquid
.Reflux of liquid into the body of the flask occurs if
the neck of the flask is excessively wide, or the length of the neck of the flask istoo short
.Because infants have a shorter eustachean tube than adults, reflux is more likely to occur in the baby.
Clincial features:
Acute suppurative otitis media passes through 4 stages:
1-Stage of hyperemia.2. Stage of exudation.3. Stage of suppuration.4. Stage of resolution. Stage of hyperemia
a-otalgia
b-fever
c- fullness in the affected ear
This stage is characterised by
a-oedema of the mucoperiosteum due to vascular engorgement.b-Otoscopy show dilated vessels along the handle of malleus
Stage of exudation
symptomsa-Pain is the most prominent feature of this stage .b- The patients may have fever and fullness in the ear.
Signs
Stage of suppurationThe exudate present in the middle ear cavity is a
very good culture medium and hence there is secondary bacrterial infection leading On suppuration
Stage of resolution is preceded by rupture of the ear drum leading
to a serous / serosanguinous / purulent disharge from the ear. When the middle ear is free from the exudate / pus the stage of resolution sets in.
complications:1- chronicity2-cranial and intra cranial complications
Diagnosis of Otitis Media1-can only be detected by examining the ear with
an otoscope.2-two tests may be performed .One of these tests
is an audiogram, The second test, called a tympanogram, measures
the air pressure in the middle ear
3-In recurrent cases or when an acute case does not respond to treatment, it may be necessary to obtain a culture from the middle ear,
Treatment:-Acute suppurative otitis media is a self limiting condition.
-If appropriate antibiotics is started early then it resolves .
-Amoxycillin is the drug of choice .-Cephalosporins may also be started in refractive cases .
-Patients who are refractory to medical management may under go myringotomy in order to decompress the middle ear cavity
Presented by :
Asmaa Beltagy. 194
Introduction
Definition:• persistent inflammation of mucosa of the
middle ear cleft
• recurrent or persistent ear discharge (otorrhoea) over 6-12 weeks through a perforation of the tympanic membrane.
• Pathology is usually irreversible and doesn't resolve spontenously.
Predisposing factors of CSOM:1. Acute necrotizing otitis media:
• occur in ill children with low immunity & suffering from measles or mumps.
• Virulent organism.
• Large ear drum perforation.
• Lead to atticoantra CSOM
• with secondary cholesteatoma
2. Eustachian tube dysfunction and obstruction:
increased negative pressure induces a chronic engorgement
a contributing factor towards lessened resistance in the event of infection occurring.
Predisposing factors of CSOM:
3. Improper treatment of ASOM.
4. Mixed infection with multiple organisms.
5. Large perforation of tympanic membrane
6. Retraction of tympanic membrane and formation of cholesteatoma.
7. General low resistance of the patient
8. Infection of mastoid process predisposes to osteitis.
Predisposing factors of CSOM:
•Microbiology of CSOM:
• gram negative bacilli i.e. Ps. aeruginosa, E. coli, and B. proteus.
Types of chronic suppurative otitis media:
Another classification:
Inactive: with only perforation.
Active: with cholesteatoma.
1. Tubotympanic disease (safe
type).
2. Atticoantral disease (unsafe
type).
Tubo-tympanic CSOM
• also known as safe disease • serious complications less commonly
occur.• infection is limited to the mucosa and
the anteroinferior part of the middle ear cleft
• The infective activity of it is related to the frequency of URT infections, the discharge tending to increase with increasing frequency of URI infections.
Etiology:• inadequately treated acute otitis media.
• Acute suppurative otitis media causing persistent perforation which is infected from bacteria in the external auditory canal.
Clinical features of tubotympanic disease:
Symptoms:1. The discharge (otorrhea) • Profuse, • Mucopurulent,• odourless, • intermittent between dry and
discharging stages
2. Conductive deafness due to• perforation of tympanic membrane • accentuated by thickening of round
window membrane due to the presence of secretions.
• Hearing loss is usually about 30 - 40 dB.
Symptoms:
• Signs (otoscopic finding):
1. Discharge:
2. Central perforation.
3. Mucosa.
4. Poylpi
Tuning fork tests show: • Rinne - Negative on the affected side• Weber - Lateralized to the good ear
Pathology of tubotympanic disease:Active stage: • ear is actively discharging. • The mucosa of the middle ear cavity
is hypertrophied, and congested.
Inactive stage: • dry perforation of ear drum, in its
antero inferior part,• The middle ear mucosa is normal.
Quiescent stage:• Perforation of ear drum is present,• the middle ear is dry and mucosa may be
normal or hypertrophied.Healed stage: • perforation of ear drum has healed by
formation of thin scar.• There may even be tympanosclerotic
patches / chalky deposits on the ear drum. • The ossicular chain is invariably intact.
Investigations:
1. Pure Tone audiometry• Show conductive hearing loss. • The hearing loss is invariably under 40 dB
2. Mastoid X-ray• Hazy mastoid3.Culture and sensitivity
Radiogram showing sclerotic (poorly pneumatized) mastoid air cells.
Radiogram showing well-pneumatized mastoid air cells.
Prognosis:• Less liable to form complication
•Main problems of the patient are otorrhea and hearing loss.
Management of tubotympanic disease:1.Conservative management:• Aural toileting • Suction method • Syringing the affected ear with warm
saline mixed with acetic acid (1.5%).
• antihistamines and nasal decongestants.
Role of antibiotics in the management of tubotympanic disease:
• depending on the culture report. • The best route of administration is topical• Ototoxic drugs are to be avoided • Ciprofloxacillin can be administered
topically • Oral amoxicillin or penicillins in adequate
doses may be beneficial.
1.Conservative management:
• Precautions:1. The ear must be kept dry.
2. Avoid blowing of the nose during URT infection
3. Pre existing sinus infections if any must be treated aggressively.
4. Presence of focal sepsis in the throat (tonsils commonly) must be ruled out.
1.Conservative management:
2. Surgical management:• Adenotonsillectomy
• myringoplasty
• Tympanoplasty (myringoplast + ossiculoplasty)
2. Surgical management:
•Cortical Mastoidectomy
Attico-antral CSOM• This is termed as unsafe
• This condition mainly affects the attic region of the middle ear.
• Pathology of attico-antral CSOM
1. cholesteatoma;
2.Osteitis , bone erosions and granulation tissue
1. Cholesteatoma:
• Cholesteatoma is defined as a cystic bag like structure lined by stratified squamous epithelium on a fibrous matrix
Types of cholesteatoma:• 1. Congenital cholesteatoma
• 2. Primary acquired cholesteatoma
• 3. Secondary acquired cholesteatoma
Congenital cholesteatoma:
• arise from embryonic cell rests present in the middle ear cavity.
• Infact congenital cholesteatoma is seen as a whitish mass behind an intact tympanic membrane.
Criteria to diagnose congenital cholesteatoma:
• The patient should not have previous episodes of middle ear disease
• Ear drum must be intact and normal• It is purely an incidental finding• If discharge and ear drum perforation is
present then it should be considered that congenital cholesteatoma has managed to erode the tympanic membrane.
Acquired CholesteatomaPrimary acquired cholesteatoma: • no history of previous episodes of otitis
media or perforation.• arise from the attic region of the middle
ear.Secondary acquired cholesteatoma: • follows active middle ear infection which
destroy the ear drum along with the annulus through marginal perforation.
• It follow acute necrotizing otitis media following exanthematous fevers like measles
Theories to explain pathogenesis of cholesteatoma:
• Cawthrone theory• Theory of immigration (invasion
theory)• Theory of invagination• Metaplastic theory • Implantation theory:
Cawthrone theory
• cholesteatoma always originated from congenital embryonic cell rests present in various areas of the temporal bone.
Theory of immigration (invasion theory)
• cholesteatoma was derived by immigration of squamous epithelium from the deep portion of the EAC. into the middle ear cleft through a marginal or a total perforation of the ear drum
• as seen in acute necrotizing otitis media.
• It explains secondary cholesteatoma
Theory of invagination• states that persistent negative
pressure in the attic region • invagination of pars flaccida causing
a retraction pocket.• This retraction pocket becomes later
filled with desquamated epithelial debris
• which forms a nidus for the infection to occur later.
• This theory is the best explaining primary acquired cholesteatoma
attic retraction pockets is classified into 4 grades:
• Grade I: The retracted pars flaccida is not in contact with the neck of the malleus.
• Grade II: The retracted pars flaccida is in contact with the neck of the malleus
• Grade III: Here in addition to the retracted pars flaccida being in contact with the neck of the malleus there is also a limited erosion of the outer attic wall or scutum.
• Grade IV: In this grade in addition to all the above said changes there is severe erosion of the outer attic wall or scutum.
Metaplastic theory: • The attic area of the middle ear cavity is
lined by epithelium.• This epithelium undergoes metaplastic
changes in response to sub-clinical infections.
• This metaplastic mucosa is squamous in nature thereby forming a nidus for cholesteatoma formation in the attic region.
Implantation theory: implantation of squamous epithelium
from external ear into the middle ear following surgery or trauma to the tympanic membrane
2. Osteitis, bone erosions and granulation tissue:
• There is sequestration of bone and the sequestrated bone is surrounded by granulation tissue.
• Bone lesions are explained by:• Pressure theory :
• Enzymatic theory:
• Pyogenic osteitis:
Clinical features of attico-antral CSOM:
Symptoms:• Ear discharge: • Hearing loss and tinnitus:
Sensory hearing loss
CHL• Vertigo • Facial palsy
Signs:oDischarge:oPerforation: Attic or in the postero-superior
quadrant Marginal oCholesteatomatous flakes and
granulation tissue may be seen through the perforation like cotton wooly
oThere is associated sagging of the posterior superior meatal wall.
o Polypi are common and hyperemic
Tunning fork tests:• Usually conductive hearing loss• Rinne`s negative in the diseased ear• Weber`s is lateralized to the
diseased ear• TFT can show mixed hearing loss
Investigation:• PTA: Early stages: conductive hearing loss with
AB gap. Late stages : mixed hearing loss • X-Ray mastoid: may show sclerosis. presence of cavity.• CT scan: show extent of bone complications
by cholesteatoma.• MRI: to show intra cranial complications.
Prognosis:• More liable to form complications
• The patient is disturbed by continous discharge and hearing loss
Treatment:• It is only surgical. No medical treatment• The aims of the surgical procedure are
as follows:
1. To exteriorise the disease
2. To create adequate ventilation to the middle ear cavity
3. To give the patient a safe dry ear.
4. To keep ear functioning if possible.
Surgical procedures are:• Atticotomy: removal of lat attic wall to get access to
attic cholesteatoma
• Canal up mastoidectomy.
• Tympanomastoidectomy
• Canal down mastoidectomy.