Conductive, Sensorineural and Mixed Hearing Loss (Congential and Acquired)

2. Mrs. Fozia Waqar
Lecturer(H.I)
GTCTD, GulbergII, Lahore

4. Outer Ear Middle Ear
Inner Ear
Pinna
External Auditory Canal
Tympanic Membrane
(Ear Drum)
Ossicles:
Eustachian Tube
(to nose and throat)
Hammer, Anvil, Stirrup
Cochlear
Auditory (or Cochlear) Nerve
Semicircular Canals
Vestibule

5.  There are four types of hearing loss;
 Conductive,
 Sensorineural,
 Mixed
 and
 Central.
 If any part of the hearing system is unable to
function,
the result is hearing loss.

6.  There are four types of hearing loss;
 Conductive,
 Sensorineural,
 Mixed
 and
 Central.
 If any part of the hearing system is unable to
function,
the result is hearing loss.

7. Sensorineural hearing loss results
from inner ear or auditory nerve
dysfunction. The sensory
component may be from damage to
the organ of Corti, an inability of the
hair cells to stimulate the nerves of
hearing or a metabolic problem in
the fluids of the inner ear. The
neural or retrocochlear component
can be the result of severe damage
to the organ of Corti that causes the
nerves of hearing to degenerate or
it can be an inability of the hearing
nerves themselves to convey neuro
chemical information through the
central auditory pathways.

8. A mixed hearing loss can be
thought of as a sensorineural
hearing loss with a conductive
component overlaying all or
part of the audiometric range
tested. So, in addition to some
irreversible hearing loss
caused by an inner ear or
auditory nerve disorder, there
is also a dysfunction of the
middle ear mechanism that
makes the hearing worse than
the sensorineural loss alone.

9.  Central hearing loss is
caused by a problem with
the auditory nerve or
sound centres. Sounds
waves may travel through
the ear but this nerve
pathway is unable to send
electrical impulses to the
brain. As a result the
hearing centres do not
receive the signals
correctly.

10. •
Conductive Hearing Loss - an impairment to the
physical mechanism of the outer and/or middle ear;
occurs as a result of trauma or Otitis Media (OM); OM
is caused by colds, flu, large adenoids or tonsils, and
allergies
• Sensorineural Loss – results from damage to the auditory
nerve or the workings of the inner ear
•
Mixed Loss – combination of conductive and sensorineural
loss
NB: Hearing impairment is not just a simple reduction in auditory
sensitivity. Perceived sounds may be distorted.

14. I. Cerumen (wax) build
up
II. Hematoma (blood
collection)
III.Foreign body in the
ear canal
 This is one of
most common causes of
hearing loss and easiest
to fix

15. Cause by direct
trauma such as;
1.Finger or cotton
swab
2.Middle ear
infections
3.Explosions

16. usually from
trauma to the ear (
dislocation of MIS)

17. Most common cause of transient
conductive hearing loss in children
I. Inflammation of the middle ear
II.Caused by Eustachian tube failure

18. Otitis Externa
infection of the ear canal that causes it to swell

19. Most common cause of transient
conductive hearing loss in children
I. Inflammation of the middle ear
II.Caused by Eustachian tube failure

20. More Surgical Treatment …
• Myringoplasty / Tympanoplasty – patches the eardrum;
not suitable for runny ears
• Mastoidectomy – removal of part of mastoid bone and
other parts of middle ear because of erosion by fluid over
long period of time
• Middle ear reconstruction

21. Behind-the-ear style sits behind ear,
amplified sound travels down a tube into
customised earmold
In-the-ear hearing aids fit inside ear
In-the-canal hearing aids are smaller and
fit the size and shape of ear canal
Completely-in-the-canal hearing aid is
worn deep inside canal and are almost
invisible.

22. • Hearing hats/head bands – bone conduction
• Personal FM systems
• Sound Field Amplification Systems

25. Importance—profound effect
On individuals
• Hinder speech, language and cognitive
skill development in pre-lingual
children
• Slow progress in schools
• Difficulty in obtaining, keeping and
performing in any occupation
• Significant social isolation and
stigmatization- poor interpersonal
development
Social and economic
• Substantial cost of treatment and
rehabilitation
• Loss of productivity

26. • Hearing hats/head bands – bone conduction
• Personal FM systems
• Sound Field Amplification Systems

27.  sensorineural hearing loss (SHL), presumed to
be of viral origin, is an otologic emergency that
is medically treated with corticosteroids.
 Corticosteroids may also be used to reduce
cochlea hair cell swelling and inflammation after
exposure to loud noise.
 Sensorineural hearing loss can occur from head
trauma or abrupt changes in air pressure (e.g.,
airplane descent), which can cause inner ear
fluid compartment rupture or leakage, which
can be toxic to the inner ear. There has been
variable success with emergency surgery when
this happens.

28.  2. Postnatal causes
a. Rh incompatibility leading to
Kirnecterus which is neurotoxic
b. Infections; most important is
bacterial meningitis ( streptococcus )
Mumps, Measles, Influenza, Herpes
simplex, Herpes zoster, Syphilis

29. Importance—profound effect
On individuals
• Hinder speech, language and cognitive
skill development in pre-lingual
children
• Slow progress in schools
• Difficulty in obtaining, keeping and
performing in any occupation
• Significant social isolation and
stigmatization- poor interpersonal
development
Social and economic
• Substantial cost of treatment and
rehabilitation
• Loss of productivity

30.  8. Ototoxic drugs: certain drugs can affect
hearing by damaging the nerves involved in
hearing. Usually this occur when large or toxic
doses are used but may also occur with lower
doses
a. Antibiotic ; including aminoglycosides (
gentamicin, vancomycin ) erythomycins, and
minocycline
b. Diuretics including furosemide and etacrynic
acid
c. Salicylates ( aspirin ) and nonsteroidal anti-
inflammatories ( NSAIDs ) such as ibuprofen
and naproxen
d. Antineoplastics ( cancer drugs )

31.  9. Acoustic neuroma a tumor in the auditory
nerve. Usually associated with ringing in the ears
 10.Meniere’s disesse a disease that affects
hearing and balance. It is usually associated with
tinnitus, vertigo, nausea, vomiting and
progressive deafness. It has gradual onset and
often progresses to deafness and severe vertigo.
The cause is unknown.
 11.Presbycusis loss of ability to perceive or
discriminate sounds as a part of of the aging
process; the pattern and age of onset may

32. Bilateral progressive hearing loss over
several months, also diagnosed as
autoimmune inner ear disease, is
managed medically with long-term
corticosteroids and sometimes with
drug therapy. Autoimmune inner ear
disease is when the body’s immune
system misdirects its defenses against
the inner ear structures to cause
damage in this part of the body.

33. Fluctuating sensorineural hearing
loss may be from unknown cause or
associated with Ménière’s disease.
Symptoms of Meniere’s disease are
hearing loss, tinnitus (ringing in the
ears), and vertigo. Ménière’s disease
may be treated medically with a low-
sodium diet, diuretics, and
corticosteroids. If the vertigo is not
medically controlled, then various
surgical procedures are used to
eliminate the vertigo.

34.  Sensorineural hearing loss from disease in the
central nervous system may respond to medical
management for the specific disease affecting
the nervous system. For example, hearing loss
secondary to multiple sclerosis may be reversed
with treatment for multiple sclerosis.
 Irreversible sensorineural hearing loss, the
most common form of hearing loss, may be
managed with hearing aids. When hearing aids
are not enough, this type of hearing loss can be
surgically treated with cochlear implants.

35.  2. Postnatal causes
a. Rh incompatibility leading to
Kirnecterus which is neurotoxic
b. Infections; most important is
bacterial meningitis ( streptococcus )
Mumps, Measles, Influenza, Herpes
simplex, Herpes zoster, Syphilis