Download External Ear

THE EAR
External Ear
Pinna
Tympanic
membrane
External Auditory
Canal
Pinna/Auricle
Location: oval-shaped appendage
on the lateral surface of the
head.
Auricleelastic cartilage+skin
Ear lobuleno cartilage (fat and
subbutaneous tissue)
Function: sound localization and
amplification.
Composition:
-thin skin with hair follicles
- sweat glands and sebaceous
glands covers supporting
structure of elastic cartilage
Diseases of the Pinna
Perichiondritis
Definition:
- An acute inflammation of
the skin and the
perichondrium that involves
the articular cartilage
- Most commonly due to
bacterial infection stemming
from a small injury in the
conchal cavity or the auricle.
(close attachment of the
skin to the perichondrium)
- Causative organisms:
staphylococci, pseudomas
Symptoms
- Severe pain (rapid onset)
- Feeling of tension
- Auricular contours are effaced
- Swelling of the concha with
marked tenderness
- Earlobes are spared
- Regional lymph nodes maybe
painful and enlarged
- Fever may occur
Treatment
– Systemic antibiotics
– Cleaning of the auricle and
ear canal
– Antiseptic/antibiotic
containing ointments
– Oral analgesics for pain
Trauma
EAR
TRAUMA
Ear Trauma
• Auricle- skin-covered cartilage, with only a thin padding of connective
tissue.
– The entire cartilage framework is fed by a thin covering membrane
called the perichondrium (meaning literally: around the cartilage)
• Accumulation of fluid (swelling) or blood (injury) between the
perichondrium and the underlying cartilage puts the cartilage in danger of
being separated from its supply of nutrients  Ear deformity (lumpy,
distorted)
•
•
•
Wrestler's Ear (cauliflower ear)repeated trauma causing thickened
auricle that resembles a vegetable.
– wrestling is one of the most
common ways such an injury occurs.
Ear lobe- devoid of cartilage, covered
with adipose tissue.Instead, it is a
wedge of adipose tissue covered by
skin.
– Tears of the earlobe can be
generally repaired with good
results. Since there is no cartilage,
there is not the risk of deformity
from a blood clot or pressure injury
to the ear lobe.
Other injuries causing major deformity.
– Lacerations, bite injuries, avulsion
injuries, cancer, frostbite, and burns
External Auditory canal
• S-shaped, approx 2.5 cm long
• Outer 1/3  cartilage , hair, cilia,
mucus, sebaceous glands,
ceruminous gland (secretes a
brown-like substance, wax-like
cerumen “ear wax”)
• Inner 2/3  bone (tympanic and
squamous portion of temporal
bone) , anteroposteriorly , only
epithelial lining on the periostium
– Skin is very thin, directly overlying the
periosteum  temperature and pain
sensitivity.
– The ear's self-cleaning mechanism moves old skin cells and cerumen
to the outer part of the ear.
– Epithelial migration of the lining of the EAC is a well-known
phenomenon and is essential for the self-cleansing mechanism of this
structure.
– In most cases, the epicenter of this migratory process appears to
reside in the vicinity of the umbo of the tympanic membrane.
– The epithelial migration takes place at a rate of approximately
0.07mm/day and serves to cleanse the canal of debris, foreign bodies,
and bacteria.
Cerumen and Cerumen impaction
Cerumen
- forms a protective film in which the fatty acids, lysozymes and the
creation of an acid milieu bacteriostatic and bactericidal) effectively
protects the skin of the ear canal.
- Consists of a combination of desquamated epithelium, thick sebaceous
gland secretions, and thinner apocrine gland secretions
- Water resistant, traps debris
Cerumen impaction
- Disturbance of the normal self cleaning mechanism or excessive cerumen
secretion.
Cerumen plug
- Sebum, exfoliative debris, contaminants
Symptoms:
- pressure sensation in the ear, concomitant hearing loss, occasional vertigo
and tinnitus
Cerumenolytics
• Ceruminolytics – “cerumen softeners”
– Hydrogen peroxide
– Mineral oil, baby oil
– Commercially prepared otic drops (Otosol,
Auralgan)
– Water
Foreign Body
• Classification
– Animate (living)
•
•
•
•
Bugs
Mosquito
Cockroach
Lice/mites
– Inanimate (non-living)
• Cotton
• Pebbles
• Small marbles
Foreign Body
Foreign Body: treatment
• Methods of removal of foreign body from the
ear:
1. Hooking out
- care is taken not to push the foreign body deeper
into the ear canal or through the tympanic
membrane.
2. Syringing
3. Removal under the microscope
Otitis externa
Definition:
- Inflammation of the external
auditory canal caused by
factors that interfere with the
normal defenses against
infection.
Barriers to infection:
- Normal cerumen film
(acidic pH, fatty acid
content- antibacterial)
- Lateral migration of the
epithelium
Predisposing factors:
1. Exogenous factors
- Water (maceration),
shampoos (alteration in
pH), manipulations with
cotton-tipped
(overcleaning/daily)
swabs, earphones/plugs
2. Endogenous factors
- eczema, allergies, metabolic
disorders
3. Local changes
- exostoses, stenoses
• S/Sx:
– Tragal tenderness
– Pain and itching of the
ear canal
– Erythema
– Edema
– Canal debris, discharge
• Treatment:
– Instructions for
prevention
– Appropriate canal
cleaning
– Antibiotics
– Pain control (analgesics)
Tympanic Membrane
-
Separates the outer ear from the
middle ear.
Consists of 2 portions: pars tensa,
pars flaccida
3 layers of the pars tensa:
1. Outer- cutaneous layer; smooth
muscle, stratified squamous
epithelium that reflects the light
2. Middle- lamina propria; with 2 layers
of connective tissue fibers. Outer
(radiate layer), inner (circular layer)
3. Inner- mucosal layer; single layer of
squamous epithelium
Pars Flaccida (Sharpnell membrane)
- Superior to the malleolar folds
- It lacks the reinforcing fibrous layer present in the pars tensa ---retracts
first in response to negative pressure in the middle ear  epithelial
pocket
Myringitis
-
Inflammation of the tympanic
membrane
Characterized by:
-
-
inflammation
Hemorrhage
Effusion of fluid into the tissue at the
end of the external car canal and the
tympanic membrane.
This self-limiting disorder
(resolving spontaneously within 3
days to 2 weeks) often follows
acute otitis media or upper
respiratory tract infection and
frequently occurs epidemically in
children.
Bullous myringitis
• Symptoms:
• Causes:
- severe ear pain
– Viral infection
- tenderness over the mastoid
– Bacteria (pneumococci,
process
Haemophilus
- Small, reddened, inflamed blebs
form in the canal, on the
influenzae,
tympanic membrane
betahemolytic
- Fever and hearing loss are rare
streptococci,
unless fluid accumulates in the
staphylococci)
middle ear or a large bleb totally
obstructs the external auditory
– organism that may
meatus.
cause acute otitis
-Bloody discharge- with ruptured
media.
blebs
- No hearing impairment
• Treatment:
– Self-limiting
– Analgesics
– Topical antibioticsprevent secondary
infection
Granular Myringitis
• Localized chronic inflammation of
pars tensa with granulation tissue
• Sequalae of primary acute
myringitis, previous otitis externa,
perforated TM
– Common organisms:
Pseudomonas
– Proteus
• s/sx:
–
–
–
–
–
–
Foul smelling discharge
Often asymptomatic
No hearing loss/significant pain
No TM perforations
“peeping granulations”
TM obscured by pus
• Treatment:
– Careful and frequent
debridement
– Topical antipseudomonal antibiotics
– Steroids
– 2 weeks of therapy
Bulging Tympanic membrane
•
Bulging tympanic membrane:
bulging tympanic membrane occurs
due to fluid collection in the middle
ear cavity.
Causes:
- Acute otitis media
- Serous effusion
- Glue ear
- Tumors
Total bulging
- a convex-appearing tympanic
membrane with loss of visualization
of the lateral process and/or the
manubrium of the malleus bone.
- diagonal cleft in the bulging
tympanic membrane where its fibers
are tightly adherent to the handle of
the malleus.
Partial bulging
- fullness of an opacified, convex
tympanic membrane with
preservation of the outline of either
the manubrium or the lateral process
of the malleus bone.
- Mobility is impaired during negative
and positive pressure.