Download The inner ear

Surgical Anatomy of the Ear Lecture No. 1
The ear is divided to External,Middle and Inner ear.
The external ear:
It composed of auricle (pinna) and the external auditory meatus.
It’s function is to collect and transmit sound to the tympanic membrane
The auricle is composed of cartilage covered with perichondrium to which the
skin are very closely adherent
The lateral surface has characteristic prominences and depressions which are
different in every individuals even identical twins,the curved
rim is helix,anterior and parallel to it is another
prominence,antihelix.Superiorly this divided into two
crura,between which is is the triangular fossa,above the two
crura is the scaphoid fossa. In front of antihelix,and partly
encircled
by
it,is
the
concha
Below the crus of the hlix and overlapping the external
auditory meatus is the tragus.Opposite to it at the inferior
limit of antihelix is the antitragus,below the antitragus is soft
area composed oaf fibrous and adipose tissue called lobule.
The external auditory meatus:
The outer third is cartilaginous, t he inner two are bony ,
the outer cartilagenous portion is
covered with skin that contain hair follicles,sebaceous glands
and
cerminous glands which secrete wax While these structures are lost in the
inner bony meatus where the
skin is thin and hair-free
Owing to the tight union of cartilage and skin any inflammatory process will be
extremely painful
The EU canal extends from the concha of the auricle to the TM is
approximately 2.4 cm ,the diameter of the canal varies
greatly between individuals and between different races
In adult the cartilagenous portion runs inward and slightly
downwards and forward
Therefor the canal is straightened by gently moving the
auricle upwards and backwards to counteract the direction
of the cartilagenous portion.
.
In the neonate,there is vitually no bony external meatus as the tympanic bone
is not not yet developed
So that the auricle must be gently drawn downwards and backwards for the
best view of the tympanic membrane
Tympanic membrane:
The tympanic membrane or ear drum is oval in shape and measures about 1cm
indiameter and supported around its periphery by a fibrous
thickening (the annulus).This fibrous annulus fits in turn into
a slot in the tympanic bone.
Ther is small deficiency superiorly,called the notch of Rivinus.
Tne ear drum consists of three layers
The outer layer is epithelial layer continous with the skin.
The middle layer which is fibrous layer
The inner layer which is mucous layer continous with the
lining with tympanic cavity
The tympanic membrane is divided into two parts:
Pars tensa and pars flaccida
Pars flaccida is the most superior part occupying the notch of
Rivinus and its medial layer is comprised of irregular elastic
fibers,hence the flaccidity,,it issmall sometime difficult to
see,it called some time (attic),perforation in this area are
potentially unsafe.
The middle ear
The middle ear is an air-containing cavity in petrous part of
the temporal bone lined with mucous membrane ,it contain
the auditory ossicles,it is narrow,oblique,slit like cavity
whose long axis lies approximately parallel to the plane of
tympanic membrane.
It divided into:
●Epitympanum→ upper most portion or attic above the level
of the mallear fold
●Mesotympanum→ middle portion
●Hypotympanum→ lower portion
The middle ear cleft or tympanic cavity is an air filled space situated within
temporal bone ,it made up of:
1 mastoid air cell
2 middle ear cleft
3 tympanic membrane
4 Eustachian tube
Function of the middle ear
Transmit sounds,which reach the TM in the form of air pressure waves,to the
inner ear where a liquid wave is set up.
The sound energy is transmitted across the middle ear by a chain of three
bones malleus,incus and stapes called ossicles the ossicular
chain together with the ear drum amplifies the sound energy
The middle ear has six portions:
Roof(superior),floor(inferior),anterior wal,posterior
wall,medial wall,lateral wall
Floor
The Ossicles
The auditory ossicles are:
Malleus
Incus
Stapes
The malleus is largest ossicle,had a head,a neck,a handle or long process,an
anterior process,and alateral process
The head is rounded and articulate posteriorly with the
incus.The neck is cnstricted part below the head.
The handle pesses downward and backward and firmily
attach to the medial structure of the tympanic membrane,it
can be seen through the tympanic membrsne on otoscopic
eqxamination.
The anterior process is a specula of bone connected to the
anterior wall of the tympanic cavity by a ligament.
The lateral process project laterally and attached to the
anterior and posterior malleolar fold
The incus posses a large body and two processes
The body is rounded and articulates anteriorly with the head
of malleus
The long process descends behind and parallel to the handle
of malleus.Its lower end bends medially and articulates with
head of stapes.Its shadow on T.M can sometime be seen on
otoscopic examination.
The short process projects backward and is attached to the
posterior wall of tympanic membrane by a ligament
The stapes has a head,a neck,two limbs(crura) and a base(foot plat
The head is small and articulates with the long process of
incus.
The neck is narrow and receives the insertion of stapedius
muscle
The two limbs diverge from the neck and attached to the
oval base or foot plate
The foot plate is 3mm x1.4mm and it lies in the oval window
The Eustachian tube
The auditory tube extends from the anterior wall of
tumpanic cavity downwards,forwards,and medially to the
nasopharynx.
Its posterior third is bony,its anterior two-third is
cartilaginous.
It serves to equalize pressure of air in tympanic cavity and
nasopharynx..
The inner ear:
Called also the labyrinth,it consists of bony capsule that is almost embedded in
the petrous part of temporal bone ,it consists of:
Bony labyrinth,comprising a series of cavities within the bone
Membranous labyrinth,comprising of series of membranous sacs and ducts
contained within the bony labriynth
Bony labryrinth
It consists of three parts :
1-The vestibule
2-The semicircular canals
3-The cochlea
They are lined by endosteum and contain a clear fluid called the perilymph
The vestibule is the central part of the bony labyrinth .In its lateral wall is the
fenestra vestibule (oval window) which is closed by the base
of stapes,and the fenestra cochleae (round window) which is
closed by secondary tympanic membrane.
Logged within the vestibule are the saccule and utricle of the membranous
labyrinth
There are three semicircular canals,superior,posterior and lateral---open in
posterior part of the vestibule by five orifices
The superior and posterior are vertical while the lateral semicircular canal is set
in horizontal position
The cochlea resembles a snail shell,it opens in the anterior part of the
vestibule.It consists of a centeral pillar(the modiolus) around
which a tube makes two and one half spiral turn.The cochlea
is divided by a membrane into scala vestibule above and
scala tympani below
Membranous labyrinth
It is logged within the bony labyrinth and filled with endolymph and
surrounded by perilymph and consists of utricle and saccule
which are logged in the bony vestibule,also contain three
semicircular ducts which lie within the bony semicircular
canals,also contain the duct of cochlea which lie within the
bony cochlea
Physiology of hearing
Airborne sound consists of vibration of the atmosphere and the purpose of
auditory apparatus is toconvert this vibrations in air to
vibrations in the inner ear fluid,and then to nerve impulses
to be transmitted along the auditory nerve to the higher
centrese of hearing.
The auricle collect sound waves to some extent,then pass along the external
auditory meatus to the tympanic membrane,the vibration of
tympanic membrane are transmitted to the malleus,incus
and stapes.
Then the sound transmitted to the oval window,causing the vibration to be set
up in the endolymphatic and prilymphatic compartments of
the inner ear,so the middle ear structure convert the sound
from air to fluid
The stapes moves in a rocking rather than a piston motion and as the fluids
cannot be compressed,these vibrations are transmitted to
the round window membrane.
This
reciprocal action of the oval and round windows is essential.
In the normal ear the presence of tympanic membrane and air containing
middle ear prevents the sound pressure waves from reaching
the round window and opposing the out ward movement of
the round window membrane,this protection of the round
window is lost when there is large perforation of the
tympanic membrane,and this is one factor which may
produce deafness.
The tympanic membrane is at its most efficient when the air pressure in the
external auditory meatus and the middle ear is equal,and
this equalization is achieved by the Eustachian tube.
Then the vibration transmitted to the inner ear produce displacement of the
basilar membrane and shearing movement between the hair
cell and tectorial membrane of the organ of Corti which
intiates nerve impulse in the fibers of auditory nerve
Physiology of balance
The balance of the body is maintained by coordination of information from
three systems;
1.proprioception. i.e sensation from muscle,joints,tendons and ligament
2.the eye
3.the vestibular system
The vestibular system cosists of the semicircular canals,the utricle and the
saccule.
The semicircular canals respond to angular (rotatory) acceleration while the
utricle and saccule respond to linear acceleration.
Lecture No.2 18/10/2017
Diseases of external ear
Congenital abnormalities: The auricle develops from series of six
tubercles,anomalies of development may be
associated with others in the middle or inner ear or
congenital malformation of the face or lower jaw.
Accessory auricles
They are usually found in the preauricular region ,but may occur
anywhere along a line extending down to the
sternoclavicular joint.They may appear to be simple
skin tags but frequently contain cartilage.
Bat ear:
This is the most common congenital deformity of the ear,the
condition is usually bilateral ,and the child may be
teased at school.
Lop ear
Less common,the superior part of the pinna appears appear to be
falling forwards;just very low set skin tag
Anotia
Total absence of the auricle,no obvious external ear
Microtia
The pinna is rudimentary and malformed usually placed lower and
more anteriorly than normal
These anomalies usually associated with meatal atrasia and other
abnormalities of middle ear.
1/3 of patient presented with other genetic abnormalities like:
Defined syndrome 9%
Facial cleft and cardiac defect 30%
Injuries to the pinna
Trauma to the pinna may result in a simple
laceration or partial or complete avultion.The only
obvious abnormality sometimes is a swelling
resulting from haematoma formation,which is an
extravasation of blood between the cartilage and
overlying perichondrium
Haematoma auris is a collection of blood between the
auricular cartilage and
Perichondrium
The haematoma is painless and inflammation is
minimal.
If left untreated, the natural outcome is thought to be
deformity of the pinna and
the classic ‘cauliflower’ or ‘wrestler's’ ear. How much
deformity is caused by a
single incident and how much is cumulative is not
documented.
More rarely, supervening infection can lead to
perichondritis and cartilage
necrosis – particularly if the cause or the subsequent
treatment breach the skin
barrier.
The pinna appears swollen and blue and the ear may be tender
with a feeling of heat and discomfort, if untreated
the pinna may become distorted and thickened ,as
the haematoma resolved ,a "cauliflower ear" may
result.
Tteatment of haematoma
Aspiration or drainage should be done,if the swelling is liquefied
this is done by syringe and large bore needle and if a
solid or organised clot is present ,it should be
opened and evacuated under strict aseptic condition
.
Whatever the method used a firm pressure dressing is applied in an
attempt to discourage more blood from clotting.
After partial or complete avultion the pinna can be reattached
,otherwise a bone anchored prosthesis can be fitted.
Infection of the pinna
Perichondritis
It is inflammation of the covering of the cartilage.It is either due to
infection of haematoma or other injury,or may
complicate severe otitis externa,or it may happen as
a complication of mastoid surgery when the
cartilage is cut in the presence of gross infection or
the infection may be introduced by aspiration or
incision, a frost bite or burn also play a
role.insertion of ear ring..
Signs and symptoms
The pinna is uniformly enlarge
The pinna become thickend
The surface of pinna is red,and shiny
Pain,sever pain
Constitutional symptoms may present
Treatment
A broad spectrum antibiotic "antipseudomonal"
A swab may be needed for culture and sensitivity
If subperichondrial abscess form,it should be incised and drain,but
incision should be delayed until definitive
fluctuation can be elicited as a premature incision
may result in further spread of infection
Skin infection of the pinna
Impetigo
It is an infection of skin by staphylococci and most commonly occur
in young children,it involve the auricle and
sometime the head and neck and face but it dose
not into the external auditory meatus.
Vesicle filled with serum arise on a reddish-purple base.
It may be secondary to the otorrhea of middle ear infection
Treatment
Removal of crust,which may be formed when the vesicle to
exudates serum which dries to form amber
crusts,the removal done with warm,sterile saline
Topical antibiotic daily for several days
Treatment of otitis media or externa
Herpes zoster
May appear around the ear as a part of Ramsay Hunt Syndrome
"Facial palsy due to the neuritis of the facial nerve
caused by herpes zoster virus ,it accompanied by
otalgia,hearing loss,vertigo"
The vesicle may heal spontaneously but painful neuralgia may
precede or follow their eruption
Tumours of the pinna
May be benign like papilloma,fibroma and chondroma
May be malignant like:
Sq.cell carcinoma present as an indurated ulcer with everted
margens,the regional lymph nodes may be involved
Basal cell carcinoma "Rodent ulcer"
Result from proliferation of basal cell of the epithelium,it is found
less commonly in the auricle than on the skin of face
and forehead.
It occur more likely over 50 year old usually asymptomatic,but it
can be invasive desrtroying the cartilage and bone it
began as flat,slightly raised lesion developed to
rolled edge with a penetrating ulce which bleeds
readily.
Conditions of EUM
Furanculosis
It is a localized form of OE resulting from infection of a single hair
follicle,which is present in lateral cartilaginous
portion of EUM ,so it confined to the lateral canal
Bacterial invasion of a single hair follicle will result in deep skin
infection,may progress to postule which may
progress to local abscess formation,often with
considerable associated odema and cellulitis.
Symptoms do not usually discriminate furunculosis from severe
otitis externa,the pinna and tragus are tender on
palpation ,otoscopic examination is difficult but it
can establish the diagnosis,samples for
bacteriological culture may guide therapy but do
not contribute to the diagnosis of the disease
Staphylococcus aureus is the most common organism causing
furunculosis,uncontrolled cases suggest that
pathogenic straine of staph.aurius are of different
phage types Staph.aurius causing other skin
infection like impetigo (furunculosis of all body site
not ontological only)
Sporadic cases happen when pathological organism are introduced
into the canal in the context of other risk factors
like: heat,humidity,trauma and maceration.
If untreated the infection usually progress to a localized abscess
which then discharge in to external ear canal ,the
infection can also spread towards the deeper tissues
where it may cause a diffuse soft tissue infection
spreding to the pinna,postauricular skin and parotid
gland.
Repeated infection can causa permanent scarring and fibrosis of
EUM which lead to subsequent meatal stenosis,this
will predispose to chronic diffuse otitis externa.
Management options
Oral antibiotic treatment is recommended in the early
stages(pencillinase resistant
penicillin,macrolide,cephalosporine,clindamycin and
quinolone.
Macrolid…..Erythromycin
Cephalosporin is one of B-lactam group
Quinololone…fluoroquinolone
….Ciprofluxacine,Norfluxacine,Levofluxacine
If there is sever spreading to soft tissue intravenous antibiotic
therapy
Foreign body in the ear
More commonly are cotton wool,insect,beads,paper,small
toy,small battery and eraser.
Most commonly seen in children inserted them into their own ear
present with pain,or discharge, caused by otitis
externa or may be asymptomatic . Live insects in the
ear are annoying due to discomfort created by noise
and movement.Removal may be very simple or
challenging and frustrating this depend in
1 nature of the FB
Living insect first killed by oil
Irregular\soft graspable non living object by pair of crocodile
forceps
Organic objects should not be syringed
Button battery should not be syringed may leak on exposure to
water
Inorganic round\smooth non graspable difficult to grasp syringing is
safe ,blunt ear hook may need microscope
2 the precise lacation of the FB
The easier access,widen diameter,elastic nature,lesser sensitivity of
canal make the removal easier
Complications
By the action of introduction of FB or FB itself or attempts of
removal,laceration of canal skin,otitis
externa.damage and perforation of TM ,multiple
attemps and use of multiple instrument are
associated with complication
Wax production
Wax is produced by the hair-bearing skin of EUM ,wax is a
combination of desequated skin and cerumen
formed by glands in the base of the hair
follicles.Hairs are present in the outer third of the
EUM .Most external canals are self-cleaning with
desequamated skin migrating up to the hair follicles
where it separated from the dermis and mixes with
the cerumen to form wax.the wax migrates down
the hair and falls out of the ear canal.
The most common is partial obstruction of the canal,this is
amenable to removal by either syringing ,probe
removal,or removal under microscopic
control,syringing is popular with GPs and nurses.
Occlusive wax,especially if adherent to canal wall may need to be
softened prior to removal ,it can reduce the need to
syringe,to soften the wax the patient is asked to
turn their head on the side to allow the external
canal to be filled with ear softener . The tragus is
then pushed in and out to aid pentration into the
wax ,the patient should continue this for about 20
minutes prior to syringing ,if the wax remains
adherent and resistance to syringing ,the patient
should be sent home with instruction to repeat
manoeuvre regularly for the rest of the day and the
next morning before syringing is attempted again
Ear toilet and Syringing
Is indicated where wax obstruct the view of the TM
Mopping the ear canal
A mop can be to used
►dry the ear canal after syringing
►►remove discharge
►►►remove debris
This allows visualization of TM and make treatment as ear drops to
become into contact with EUC
LectureNo 3
26/10/2016
Otitis externa
Is a generalized condition of the skin of EUC is characterized by
general oedema and erythema associated with ichy
discomfort and usually an ear discharge
Acute otitis externa affects approximately 4 of every
1000 children and
adults per year
Approximately 80% of cases occur in the summer
Predisposing factors
❶ Anatomical
like Narrow EUM (heridatory,iatrogenic,exostosis,etc.)
Obstruction of the normal meatus(keratosis obturance,
FB,hearing aid,hirsute canal,etc.)
❷ Dermatological
like eczema,sebhorrhic dermatitis
❸ Allergic
like exposure to topical medication
❹ Physiological
like humid environment or immunocompromization
❺ Traumatic skin maceration (bathing), ear
probing,laceration,radiotherapy
❻ Microbiological
like in active CSOM,exposure
Pathology
The clinical course of OE has been divided to following stages
1 preinfalmmatory
The protective lipid/acid balance (normal pH 4-5) is lost and
stratum corneum become oedematus ,blocking off
the sebaceous and apocrine glands producing aural
fullness ,itching.With increase oedema and
scratching there is disruption of epithelial layer and
invation of resident or introduced organisms
and will result in stage 2
2 Acute inflammatory stage (Mild,Moderate or Severe)
More oedema,obliteration of the lumen Mild,Moderate or Severe
with thickening exudates. In severe cases increasing
pain ,auricular changes and cervical
lymphadeopathy,after six months or some consider
chronicity after inflammation lasting longer than
three weeks as entering the chronic phase,there is
some evidence that individuals whose skin has a
tendency to remain at low pH are more prone to
develop a chronic problem
3 Chronic stage
Is characterized by thickening of external canal skin and fibrous
canal stenosis .
Microbiology
Pseudomonas aeruginosa was the most common
bacteria responsible for infections.
Staphylococcus sp were the next most common pathogens.
Fungi were responsible for only 2% of cases, but may be
more prominent in casesof persistent or chronic
infection
Investigations
Investigations are rarely required for cases of otitis externa.
Cultures for
bacteria and fungus are indicated in cases of persistent or
refractory
infection, particularly to identify fungal infection
Clinical Manifestations
Pain is a common symptom associated with bacterial infection. The
pain may be severe and is exacerbated by manipulation of the
auricle or the tragus. Itching may be experienced in early bacterial
infections, and in fungal infections and in all forms of chronic otitis
externa. Aural fullness and decreased hearing may be experienced
in any case of otitis externa resulting in accumulation of debris in
the ear canal. Otorrhea is more common in bacterial infections.
Examination of the canal may reveal the following findings:
1. An erythematous canal with scant discharge in cases of early
bacterial otitis externa
2. An edematous canal filled with purulent-squamous debris in
cases of well-established bacterial otitis externa
3. An accumulation of white debris sprouting hyphae best seen with
the otologic microscope, typical of candidal otitis externa
4. An accumulation of a moist white plug dotted with black debris
(“wet newspaper”) typical of Aspergillus niger
5. A maculopapular eruption on the conchal bowl and in the ear
canal consistent with an allergic reaction to a topical agent (e.g.,
neomycin)
6. A thickened, erythematous canal associated with an allergic or
contact dermatitis
7. Granulation tissue in the canal and on the tympanic membrane
caused by chronic infection
Treatment
Careful débridement of the ear canal in any case of otitis externa is
crucial to facilitate clearance of the infectious organism and to
allow topical medications to reach the target tissue.
If the ear canal is so edematous that topical medication would not
reach its medial extent, an ear wick may be inserted.
Classically, the physician made these fromstrands of cotton.
Currently available Merocel wicks (Medtronic, Inc.), offer better
absorption of the drug, however, and
expand when wet to decrease canal edema substantially
Antibiotic drops remain the mainstay of treatment for otitisexterna.
For many years mainstay of treatment was a combination solution
of polymyxin, neomycin, and hydrocortisone (PNH)
Quinolone antibiotics are available in otic and ophthalmic solutions.
Ciprofloxacin is available as an otic preparation combined with
hydrocortisone and as a newer
Fungal otitis externa can be treated with meticulous débridement
of the ear Clotrimazole
1% solution (Lotrimin) is available over the counter and provides
broad-spectrum antifungal activity
ketoconazole ointment are effective as well.
Complications
If untreated,mild attachs of otitis externa can spontaneously
resolve as the epithelial barrier becomes reestablished ,the piloapocrine unit produce normal
secreations and the pH of the canal returns to
normal.
If the inflammation progress faster than repair pain will increase
,otorrhea,and oedema of the canal
occur,lymphadenopathy due to rich lymphatic
drainage.
This can lead to perichondritis,chondritis,cellulits,parotitis and\or
erysipelas,in immunocompromised patient
malignant otitis externa can develop
Malignant otitis externa
Is an aggressive and potentially life threatening infection of the soft
tissue of the external ear and surrounding
structures. quickly spreading to involve the
periostium and bone of the skull base.it is not a
neoplastic process so it is a misnomer.
Sometime called necrotizing OE, or skull base osteomyelitis.
Staging
Stage 1 malignant OE with infection of soft tissue beyond the
EUM,but negative bone scan
Stage 2 soft tissue infection with positive bone scan
Stage 3 as above with cranial nerve paralysis
Stage 4 meningitis,empyema,sinus thrombosis or brain abscess
Lecture 4 Acute Otitis Media
The term Acute Otitis Media implies a viral or bacterial infection of
the mucosal lining of theMiddle ear and mastoid air
cell system
AOM is one of the commonest illness in childhood, defined as
inflammation of the middle ear cleft of rapid onset
and infective origin 25% of child prescriptions in
USA
The adult cases constitutes 16% of all cases seen,making it a not
infrequent event in healthy adult
AOM is of four subgroups:
1 Sporadic
Episodes occurs as frequent isolated events,typically occurring
with URTI
2 Resistant AOM
Persistence of signs and symptoms of middle ear infection beyond
3-5 days of AB treatment
3 Persistent AOM
Persistent or recurrence of symptoms and signs of AOM within six
days of finishing a course of AB
4 Recurrence AOM
Either three or more episodes of AOM occurring within a six
months period,or at
least four to six episodes within a 12 month period
Diagnosis
Diagnosis by symptomatology alone is inaccurate because of young
age of most patients,and nonspecific nature of the
symptoms.
One-third of children may have no ear related symptoms ,twothirds may be apyrexial
Symptoms:
1 Rapid onset otalgia
2 Hearing loss
3 Otorrhea
4 Fever
5 Excessive crying
6 Irritability,restlessness
7 Coryzal symptoms
8 Rhinitis
9 Cough
10 Vomiting
11 Poor feeding
12 ear pulling,rubbing of the ear
13 Clumsiness
Signs
The child may appear unwell ,and may rub his or her ear ,the
diagnosis is often confirmed by otoscopic
assessment of TM colour,position and mobility .
The TM usually opaque,most commenly yellow or yellowish pink,
being red in only 18-19%.
The position of TM reliably predect OME only when it is bulging
hypomobility demonstrated by pneumatic otoscopy
Mucopurulent otorrhea may be seen
While in adult the normal pearl grey and transparent with clear
light reflex exclude AOM ,the inject TM indicate
early otitis media
But this may also caused by crying or by a common cold .A clear
difference between both ears support the diagnosis
of AOM ,
an intensely red TM confirm the diagnosis as well
buldging
Of TM indicates the presence of liquid in the middle ear under
pressure ,perforation of TM with otorrhrea (with
acute clinical symptoms)also confirm the diagnosis
of AOM adult with AOM consults their physician
within 48 hrs which is more sooner on average than
children
Challenges in otoscopic examination
►poorly functioning otoscope
►►Moving child's head
►►►Narrow ear canal
►►►►Natural redness of TM in a screaming child
►►►►►Wax
►►►►►►Untrained eye
Investigations
1 tympanometry to establish the presence of middle ear effusion
2 Tympanocentesis and culture of middle ear effusion
3 Bacterial swab of persistent otorrhea
4 Nasopharyngeal swab for bacterial culture
5 tests for iron deficiency anaemia and white blood cell disorders
6 Immunoglobulin assay IgA,IgG,IgM
Differential diagnosis
1 pain may be referred from tonsillitis,teething,TM joint disorder
2 Red TM in screaming child
3 Acute mastoiditis
4 OME
5 Trauma
6 OE
7 Ramsey Hunt syndrome
8 Bullous maryngitis
9 Rarely,AOM may be the first indication of serous underlying
disease,such as leukeaemia and wegener's
granulomatosis
Microbiology
Viruses
Respiratory syncytial virus RSV
Influenza A virus
Parainfluenza viruses
Human rhinivirus
Adenovirus
Bacteria
While in adult
Haemophilus influenza 16-37%
same in adult 26%
Moraxella catarrhalis 11-23%
21%
streptococcal pneumonia 21
St. coccus pyogene
Moraxilla catarhalis
Staphylococcus aureus
streptococcus areus
Pneumococci
Routes of spread of infection
1 Eustachian tube
3%
3%
Is the main route by which the organisms reach the middle
ear,shorter,straighter,and more patulous is more
prone to develop infection in middle ear like in
native Americans more than white
2 TM
perforations
Pathogen entry through TM perforation or ventilation tube
(grommet)
Most commonly with water exposure
3 Haematogenic
Viral identification in the blood and middle ear was described
Risk factors
1 Genetic factors
There is familial tendency to develop OM and there is gene
association ,certain HLA human leukocyte antigen
classes have
been associated with increase risk
OM
2 Immune factors
Low level IgG2 subclass have been reported in several studies to
be more common in otitis prone child, Cytokines
like
interleukins affect host defence
and cause persistent infection
3Environmental factors
Seasonal URTI in winter,poor socioeconomic status,poor
housing,overcrowding,and bottle feeding as breast
feeding for
three months is protective against
AOM
4 Systemic disease and syndromes
Iron deficiency anemia
Turner's syndrome
Down syndrome
Cleft palate
Management
Most children with AOM will get better quickly without treatment
and,2\3 recover within 24 hour
Conservative treatment:
Most children will benefit from simple analgesias and anti-pyrexials
like paracetamol,ibuprofen
Antibiotics:
If not prescribed initially ,should be given if t he child failed to
improve after Watchful Waiting for 2-3 days, also
given to child with irregular illness course,and given
also to high risk child.
Five days treatment was enough in uncomplicated cases, in low risk
child, without recurrence or TM perforation
Amoxicilline remains the first choice higher than previously
recommended dose 80mg\kg\day
Antihistamines and decongestants:
There use could not be supported,but combining the two show
slightly reduce persistence AOM
Surgery:
Maryngotomy was practiced in pre-antibiotic era,many studies
show that AB plus maryngotomy had no advantages
over AB alone
Complications
Extracranial
1Tympanic membrane
TM perforation is associated with purulent or bloody otorrhea and
immediate relief of pain typically occur in posterior
half of pars tensa and may predispose to further
retraction pockets,the outcome of perforation is
one of these four
1 Healing of perforation in most cases
2 Resolve infection but perforation persists
3 Persist perforation and otorrhea manifested as CSOM usually
after 3 months
2 Acute mastoiditis
common in pre AB era
Mastoiditis was
Usually preceded by 10-14 days of middle ear symptoms and it is a
disease of childhood
Microbiology is little bit differ from AOM
St pneumonia
St pyogenes
Pseudomonas aeruginosa
Staph aurius
H influenza is less common
Presented in four stages
Stage 1
During episodes of AOM infection may naturally extend to mastoid
cavity and be visualized radiologically this is not
considered as complication and not associated with
typical sign of mastoiditis
Stage 2
Periosteitis infection may spread to periosteum via emissary veins
Stage 3
Osteitis when the infection has begun to destroy the bone of
mastoid air cell and subperiosteal abscess may
develop
Stage 4
Subacute or masked mastoiditis in incompletely treated AOM after
10-14 days of infection ,sign may be absent but
otalgia and fever persist this can also progress to
serious complications
Symptoms
Otalgia
Irritability
Pyrexia less common in thoe treated with AB
Otorrhea
On examination
Red or bulging TM,normal TM not exclude the diagnosis
Retroauricular swelling
Retroauricular erythema
Tenderness is typically on (MacEwen's triangle) on palpation
through the conchal bowl
Pinna protrution
Investigations
Full blood count
C-reactive protein
Blood culture
CT scan of mastoid may show evidence of osteitis,abscess or
intracranial complications
Differential diagnosis
AOM
OE
Furunculosis
Reactive lymphadenopathy
Management
Maryngotomy with or without ventilation tube
High dose IV AB
Drain of abscess with or without cortical mastoidectomy
3 Petrositis
Extension of infection to petrous apex, the classical features of
Grandenigo's traid are not always present (VI nerve
palsy+sever pain in trigeminal nerve
distribution+middle ear infection)
4 Facial nerve palsy
5 Labyrinthitis
Bacterial toxins may enter the round window due to change of it's
permeability during acute infection
Sever vertigo,nausea,vomiting,nystagmus,permanent
Intrcranial complications
Meningitis
Extradural abscess
Suubdural empyema
Sigmoid sinus thrombosis
Focal otitic encephalitis (cerebritis)
Brain abscess
Otitic hydrocephalus
Lecture 5 chronic suppurative otitis media
Chronic suppurative otitis mediaLecture 7
Chronic suppurative otitis media
Repeated or proloned bouts of acute otitis media ,often in
childhood,can cause damage to the tympanic
membrane and a non-healing perforation can
occur,the perforation may occupy either the pars
flaccida or the pars tensa.
The perforation may be further described as central or marginal
depending to their position relative to the annulus
of the drum
Pathological classification
Inactive mucosal COM (dry type)?
There is permanent perforation of the pars tensa ,but the middle
ear and mastoid
mucosa is not inflamed
Active mucosal COM (perforation with otorrhoea)?
There is chronic inflammation within the mucosa of the middle ear
and mastoid ,with varying degree of
oedema,submucosal fibrosis,hypervascularity,and
infiltration with lymphocyte,plasma cells and
hiseocyt, thus simple closure of perforation in active
mucosal COM without surgical removal of infected
mucosa and granulation tissue from the mastoid is
fraught with failure to control the disease
Active mucosal COM is often associated with
resorption of parts or all of the oscular
chain(resorptive osteitis)
Healed COM
Thinning and/or local or generalized opacification of the pars tensa
without perforation or retraction
Chalk patches tympanosclerosis plaques or definition of healed
otitis media are thin replacement
membrane,usually circular in outline and suggestive
of an old perforation
?Inactive squamous epithelial COM (retraction,atelectasis and
epidermization)
Negative static middle ear pressure can result in retraction
(atelectasis) of the tympanic membrane,a retraction
pocket consists of an invagination into the middle
ear space of a part of the ear drum,and may be fixed
when it is adherent to structures of the middle ear
or free when it can move madially or laterally .
epidermizatin is a more advance type of the retraction and refers to
replacement of the middle ear mucosa by
keratinizing squamous epithelium without retention
of keratin debris,the area of epidermization may
involve part or all of the middle ear cavity.it doesnot
progress to cholesteotoma or active suppuration
.therefore epidermization in itself not an indication
for surgical intervention.
Active squamous epithelium COM (cholesteatoma)?
Cholesteatoma ia a poor name since this condition is not a tumour
and nothing to do with cholesterol infact it is acyst
or sac of keratinized squamous epithelium (skin)
and most commonly occur in the attic or
epitympanum part of the middle ear
the name keratoma will be more correct because it
is retention of keratin debris so it is a cyst or sac
filled with keratin and be quite dry or associated
with active bacterial infection leading to profuse
malodorous otorrhoea .
Cholesteatoma are potentially dangerous because of their potential
to incite resorption of bone leading to intratemporal
or intracranial complications.
Symptoms and signs of cholesteatoma
1 foul smelling discharge
2conductive hearing loss
3attic retraction filled with squamous debris
4Discharging attic perforation
5 attic aural polyp
Patient may present with complication of cholesteatoma
1 facial palsy
2vertigo
3intracranial sepsis
Cholesteatoma are rarely congenital,and these are though to arise
from squamous rest cell within the middle ear .
Aetiology
The exact aetiology is unknown ,negativre pressure within the
middle ear has a maximal effect on the thin pars
flaccida of the TM ,this will ballon backwards
forming a so-called retraction pocket
The migratory epithelium of the outer layer of the TM may now fall
into this pocket and in some cases cannot escape.
This ball of squamous debris slowly enlarges and invariably
becomee infected with pseudomonas,hence the
foul otorrhea.
It tends to grow upards into the attic and backwards into the
mastoid.
Cholesteatoma is able to erode bone and therefore can damage any
of the important structures in or around the middle
ear and mastoid like
1 ossicles lead to conductive deafness
2facial nerve lead to facial palsy
3labyrinth lead to vertigo
4Tegman tympeni (roof of the middle ear) erosion lead to
intracranial sepsis
Treatment
Surgical removal,the operation required depends on the size and
extent of the disease
Aetiology of COM
Why some individuals progress from acute otitis media to COM is
not clear but some risk factors are envolved
1 Genetic and race
There is high incidence of COM in native Americans
2 Environment
COM is higher in lower socioeconomic groups the reason is
multifactorial like
general health
scores,maternal smoking, and day care
attendance,the effect of breast feeding is weak and
doesn’t show statistical significant and there is
decrease in prevalence due to improvement of
health care and in housing condition
3 Eustachian tube dysfunction
ETD is more common in COM than in normal individuals,it is not
known however if the Eustachian tube dysfunction
is the intiating factor in COM or whether it is a
result of COM
4Gastro-oesophageal reflux
Recently there is a role of GERD in ear disease
5 Craniofacial abnormalities
The incidence of COM in cleft palate is high ,the tensor veli palatine
muscle is
hypoplastic in cleft palate childrena
and may predispose to ETD
6Autoimmune disease
One study present 29% of patient with ankylosing spondylitis
present with COM
7 Immune difficiency
There is no evidence that AIDS patient have higher risk of COM
although they
have higher risk of aural poyp.
Diagnosis and assessment
Otoscopy with the aid of microscope is the gold standered for the
diagnosis of COM
Otoscopy done for the patient and microscopic magnification to be
used with an appropriately sized speculum to held
the EUM open with facilities of aural toilet like
suction,irrigation,mopping and instrumental
removal.
Rigid endoscopy can give a good general overall view of anatomy
and pathology and be helpful in viewing the anterior
recess of the tympanic membrane which is often
blocked from view by an anterior canal bulge,and it
is good for teaching and to assess pathology and
finer ear anatomy but its resolution and colour is
not as good as microscope.
Prior to otoscopy operation scars will be looked for,endaural scar
and postauricular scarAnatomicaly the pars tensa
can be divided into four quadrants but
pathologically yhe perforation could be
anterior,posterior or inferior hence division into
thirds rather than quadrants is preferred,
percentage are preferred to non defined terms such
as smal,large or subtotal.
All perforations of the pars tensa are central indicative of
tubotympanic disease.
The pars flaccida in the attic has always be cleared to assess
pathology which may occur alone or with pars tensa
disease. All attic disease is attico-antral and
marginal , the term marginal goes along with the
absence of an annulus,which is not normally in attic
pars flaccida ,if the term marginal is applied to pars
tensa pathology ,its interpretation becomes
confusing and should be avoided.
Otoscopy Inactive (mucosal) COM
Permanent perforation of the pars tensa but the middle ear
mucosa is not inflamed
The diagnosis implies permanent perforation of the pars tensa and
the middle ear
mucosa that seen through the perforation is inactive
Otoscopy Active (mucosal) COM
Permanent defect of the pars tensa with an inflamed middle ear
mucosa which produces mucopus that may
discharge ,activity is evident usually with generally
inflamed middle ear mucosa ,but sometime with
granulation tissue that is localized
and may become polypoidal
Otoscopy Inactive (squamous epithelial) COM
Retraction of the pars flaccida or pars tensa .pars tensa
retractions are primarly of the posterior TM ,many
classifications used to document their degree like
Sade and Berco.
The rtraction of pars tensa may be totally in view or there may be
area out of view.
Pars flaccida retraction was clssified by Tos et al into four stages
Otoscopy Active (squamous)COM
Retraction of the pars flaccida or tensa that has
retained squamous epithelial debris and is
associated with inflammation and the production of
pus,often from adjacent mucosa Cholesteatoma are
the end stage retraction of pars tensa or flaccida
Management of csom
Active mucosal CSOM
Two main symptoms which is otorrhea and hearing impairment.
It may remain active,become inactive,or progress to
complication.continuing activity may be the result
of infection with a particularly virulent or persistent
organism ,commonly pseudomonas,impaired
immunity group and deprived communities in the
developing world should be kept in mind.
Continuing activity of CSOM is likely to result in damage to the
ossicular chain and potentially to the inner ear
(relatively rare) ,this due to infected with multiple
organism,and due to inflammatory reaction in the
middle ear associated with granulation tissue which
is most likely factor in ossicular damage this will
result in nonspecific changes in bone with
osteoclastic and osteoblastic activity which result in
resorption and remodeling of the bone mainly to
the long process of incus and stapes super structure
Aural toilet
Suction clearance with otoscopic aid or microscope,some clinitian
use gentle syringing with saline or antiseptic agent
cotton ,aural toilet may be carried with cotton wall
on probe,but now it is not effective only effective
for patient to clean his or her own ear perior to
insertion of topical medication
Topical medication
topical antibiotic is the most effective means of treatment of active
otorrhea in active CSOM
Topical antibiotic are more effective than oral or intramuscular
(meta -analysis of randomized controlled trails )
Topical antibiotics with steroid are commonly used ,gentamicine or
neomycin with hydrocortisone is most popular
agent used for many years ,other combination is
topical quinolone (ciprofluxacine,ofloxacine),topical
combination polymyxine B,neomycine,and HC
(otosporine)
Aminoglycoside is ototoxic in parenteral admistration and some
anecdotal repots of ototoxic effect in topical use in
human,but it is difficult to separate the effects of
treatment from the effects of the disease itself
Although quinolones are less effective in reducing otorrhea than
aminoglycoside but quinolones are preferable to
aminoglycoside in active CSOM
Reccurance of activity 4-6 weeks after completion of treatment
was reported in 5-43%
Surgery
In those cases that do not become inactive on medical treatment
Cortical mastoidectomy with myringoplasty ,maryngoplasty alone
can be done when make active ear inactive
In some cases aural polyps are found protruding from the middle
ear ,this can be removed or partially removed ULA
or UGA remembering that polyp can be attached to
stapes superstructure or facial nerve.
Cauterization of polyp with silver nitrate on a astick is helpful
Laser used in removal of aural polyp to reduce bleeding on removal
Inactive mucosal COM
Surgery
Myringoplasty….reconstruction of TM and/or ossicular
chain,myringoplasty is tympanoplasty without
ossiculoplasty
Underlay graft of temporalis fascia or prechonderium,
In spite of that thedegree of hearing loss depend on size of
perforation Myringoplasty has a small
improvement in hearing it does not make the ear
the normal ear ,Air bone gap of 35dB or more is due
to erosion or fixation of ossicular chain
Ossiculoplasty
Put a prosthesis between handle of malleus and head of
stapes,when stapes overstructure is missing the
handle of malleus is connected to the stapes
footplate
2 hearing aid
Inactive squamous COM
Retraction of the pars tensa or pars flaccida with a potential to be
active with retained debris (cholesteatoma)
1Aural toilet
Small retraction pocket can be managed by regular suction
2Management of nasal disease
Ther is evidence that a poorly function ET plays a role in the
pathogenesis ot tympanic retraction ,so we have to
look for sinonasal diseases like allergy and infection
3 surgery
Surgery for the TM,surgery for ventilating the middle ear
Restore the normal anatomical appearance of TM
A excision without graft
B excision with myringoplasty
C excision with myringoplasty and cortical mastoidectomy
Ventilation of the middle ear
Active squqmous AOM
Surgical removal is the only effective treatment in cholesteatoma
Healed otitis media
HA
Young patient need ossiculoplasty success rate is limited
Complications of COM,OM,
Complication occur when the infection spread outside the middle
ear
It is either extracranial or intracranial ….
………
Extracranial
1 Sensoryneural hearing loss
2 Labrynthine complication Acute bacterial labrynthitis
3 Facial nerve complication
Intracranial
1 meningitis
2 Intracranial abscess
3 Lateral venous sinus thrombosis
4 Otitic hydrocephalus