2. Disorders of the Outer & Middle Ear
Causes a conductive hearing loss (CHL)
On the audiogram, you would find normal bone
conduction thresholds and abnormal air conduction
thresholds
Tympanograms (test of middle ear function) will be
abnormal
6. Outer Ear Pathologies
Anotia
o absence of the outer ear
Microtia
o malformation of the outer ear
Wax build-up
Otitis Externa
o aka swimmer’s ear or outer ear infection (bacterial)
Atresia
o absent or closed earcanal
Stenosis
o narrowing of EAC
Otomycosis
o fungal infection of EAC
Exostoses
o bony growth in EAC, common in cold water swimmers
Osteoma
o bony tumor in EAC
7. Tympanic Membrane Pathologies
Myringitis
o inflammation of TM
Tympanosclerosis
o thickening and scarring of the TM
Perforation
o hole or tear in the TM
o May be caused by fluid pressure due to otitis media,
barotrauma (rapid pressure change due to flying or
scuba diving), or self-inflicted (q-tip use)
8. Middle Ear Pathologies
Otitis media (OM)=middle ear infection
Otitis media with effusion (fluid)
May be acute (sudden onset) or chronic (long-lasting)
Eustachian tube dysfunction
malfunction of Eustachian tube
Causes retraction of TM and popping, crackling,
pressure, pain
Patulous Eustachian tube
Eustachian tube is stuck open (patent)
Autophony, hearing one’s own voice in head, is common
complaint
Otosclerosis
Bony growth over stapes footplate and fixation to oval
window
Ossicular chain discontinuity
Loss of connection between the ossicles; usually due to
head injury
9. Treatment for Conductive HL
Medical
Antibiotic eardrops, oral antibiotics for bacterial infections
Surgical
Myringotomy (incision in TM), pressure-equalization tubes,
ossicular repair, stapedectomy (removal of stapes and
prosthesis placement)
Amplification
CHL is very easy to fit with a hearing aid(s)
Because the sensory cells of the cochlea are healthy, CHL
only requires amplification to power through the middle ear
pathology. Once the sound gets past the middle ear
problem, it is clearly transmitted through the remainder of
the auditory system with ease.
10. Disorders of the Inner Ear
Results in a (primarily) sensorineural hearing loss
(SNHL)
On the audiogram, you would find abnormal bone
conduction and air conduction thresholds
Tympanograms (test of middle ear function) will
usually be normal
12. Normal Tympanogram
Tests middle ear function
= eardrum, ossicles,
eustachian tube
Measures changes in the
movement of the eardrum
Type A=normal
13. Inner Ear Pathologies Presbycusis
Age-related hearing loss; effects the high frequencies first
Noise-Induced Hearing Loss (NIHL)
Exactly like it sounds; dependent on intensity, duration, and
type of noise exposure, classic “noise notch” seen from 3 to
6 kHz, with recovery at 8 kHz
Meniere’s disease
Overacummulation of endolymph in the cochlea;
characterized by attacks of vertigo, tinnitus (roaring), low-
frequency SNHL (usually unilateral), nausea/vomiting
Ototoxicity
High-frequency SNHL due to damaging effects of certain
drugs (most notably aminoglycoside antibiotics and
platinum-based chemo drugs)
Perilymph fistula
Hole (fistula) at the oval window, in which perilymph leaks
into middle ear. Fluctuating HL (SNHL or Mixed HL) and
dizziness common.
Superior Semicircular Canal Dehiscence
Hole or thinning of the bony lining of the superior SCC;
symptoms: fullness, autophony, dizziness with/sensitivity to
14. A note about sudden hearing loss
Sudden, idiopathic sensorineural hearing loss is
any SNHL that occurs very suddenly with no
identifiable cause
Usually unilateral
May be partial or complete loss of hearing
Often accompanied by dizziness and tinnitus
Requires IMMEDIATE medical referral
Do not assume that a patient has wax, an infection,
or a broken hearing aid if they call complaining of a
sudden inability to hear. If you can’t see them
ASAP refer them to their primary doctor or an ENT
for a same-day appointment, if possible. Steroid
treatment that occurs within the first week of the
hearing loss may result in improved/recovered
hearing.
15. Treatment for SNHL
Hearing Aids
Hearing Assistive Technology
Cochlear Implants
16. Mixed HL in the Right Ear
Mixed hearing loss
(MHL) is a
combination of
sensorineural hearing
loss with a conductive
HL component
Commonly seen in
older adults with
presbycusis and
middle ear disorder
May be seen in cases
of perilymph fistula,
head injury,
barotrauma
Imagefrom:
asha.org
17. Treatment for MHL
Because MHL is a combination of CHL and
SNHL, the treatment should also take a combined
approach
Always refer to ENT for medical treatment FIRST
Finally, amplify the hearing loss that remains