Hearing loss ppt

1. By:
Rabiu Hassan Musa

2. DEFINITION
The World Health Organization defines
“disabling hearing impairment” in
children under the age of 15 years as an
unaided hearing threshold level in the
better ear of 31 dB HL or more using
pure tone averages at 0.5, 1, 2 and 4
kHz.

3. On the other hand, Hearing loss exists when
there is diminished sensitivity to the sounds
normally heard. The terms hearing impairment
or hard of hearing are usually reserved for
people who have relative insensitivity to sound
in the speech frequencies. The severity of a
hearing loss is categorized according to the
increase in volume above the usual level
necessary before the listener can detect it.

4. Deafness is defined as a degree of impairment
such that a person is unable to understand
speech even in the presence of amplification.
In profound deafness, even the loudest sounds
produced by an audiometer (an instrument
used to measure hearing by producing pure
tone sounds through a range of frequencies)
may not be detected. In total deafness, no
sounds at all, regardless of amplification or
method of production, are heard.

5. SPEECH PERCEPTION
Another aspect of hearing involves the
perceived clarity of a sound rather than its
amplitude. In humans, that aspect is usually
measured by tests of speech perception. These
tests measure one's ability to understand
speech, not to merely detect sound. There are
very rare types of hearing impairments which
affect speech understanding alone

6. INCIDENCE AND PREVALENCE
 Globally hearing loss affects about 10% of the
population to some degree.
 It caused moderate to severe disability in
124 million people as of 2004 (108 million of
whom are in low and middle income countries).
Of these 65 million developed the condition
during childhood.
 The problem of hearing loss is particularly
significant in older adults, affecting about 30% to
35% of people between the ages of 65 and 74, and
more than 40% of those over age 75.

7.  The prevalence of childhood hearing loss is 1.2
to 1.7 cases per 1000 live births and the
prevalence increases up to 6 years of age as a
result of meningitis, delayed onset of genetic
hearing loss, or delayed diagnosis.
 The prevalence is greater still in developing
countries because of lack of immunization,
exposure to ototoxic drugs, and consanguinity.
 Profound hearing loss (hearing loss > 90 dB)
has far-reaching, lifelong consequences in
children.

8. RISK FACTORS
 Aging: Exposure to sounds over the years can
damage the cells of your inner ear.
 Heredity: Genetic makeup may make you more
susceptible to ear damage from sound or
deterioration from aging.
 Occupational noises: Jobs where loud noise is a
regular part of the working environment, such as
farming, construction or factory work, can lead to
damage inside your ear.
 Recreational noises: Exposure to explosive noises,
such as from firearms and jet engines, can cause
immediate, permanent hearing loss.

9.  Some medications: Drugs, such as the
antibiotic gentamicin and certain
chemotherapy drugs, can damage the inner
ear. Temporary effects on your hearing,
ringing in the ear (tinnitus) or hearing loss
can occur if you take very high doses of
aspirin, other pain relievers, antimalarial
drugs or loop diuretics.
 Some illnesses: Diseases or illnesses that result
in high fever, such as meningitis, may damage
the cochlea.

10. CLASSIFICATION
 Conductive hearing loss,
 Sensorineural hearing loss, or
 Mixed hearing loss.

11. ETIOLOGICAL FACTORS
Conductive Hearing Loss
 External ear conditions
 Impacted ear wax or foreign body
 Otitis externa
 Middle ear conditions
 Trauma
 Otitis media
 Otosclerosis
 Tumors

12. Sensorineural Hearing Loss
• Aplasias
• Abiotrophies
• Intrauterine/perinatal damage
• Trauma e.g. head injury, middle ear surgery
• Sudden (idiopathic) sensoryneural hearing loss
• Noise induced hearing loss
• Central nervous system infections (e.g., meningitis)
• Degenerative conditions
• Age related presbyacusis
• Vascular conditions
• Ototoxic drugs
• Acoustic neuroma
• Meniere’s disease

13. Mixed Conductive and
Sensorineural Hearing Loss
 Middle ear conditions
 Temporal bone fractures

14. PATHOPHYSIOLOGY

15. CATEGORIES OF HEARING LOSS
 Slight hearing loss : 16 - 25 dB
 Mild hearing loss : 26 - 40 dB
 Moderate hearing loss: 41 - 55 dB
 Severe hearing loss : 71 - 90 dB
 Profound : More than 90 dB
(American National Standards Institute)

16. CLINICAL MANIFESTATIONS
 Muffling of speech and other sounds
 Difficulty understanding words, especially against
background noise or in a crowd of people
 Trouble hearing consonants
 Frequently asking others to speak more slowly,
clearly and loudly
 Needing to turn up the volume of the television or
radio
 Withdrawal from conversations
 Avoidance of some social settings

17. DIAGNOSIS
 Air Conduction, Conventional or Standard
Audiometry
 Bone Conduction
 Rinne and Weber tests
 Audiometry
 Tympanometry
 Acoustic reflex testing
 Word Recognition
 Acoustic Immittance
 Otoacoustic Emissions (OAEs)
 Auditory Brainstem Response (ABR)

18. Medical Management
Antibiotics
Analgesics
MANAGEMENT

19. Surgical Management
Stapedectomy
Tympanoplasty
 Cochlear implant

20. Nursing Management

21. PATIENT’S PROBLEMS
 Disturbed Sensory Perception: Auditory
 Impaired Verbal Communication
 Social Isolation

22. REHABILITATION
Audiologic rehabilitation classes
Learning good listening strategies
Establishing guidelines for
communicating with those around
you

23. Assistive Listening, Hearing
Enhancement and Alerting
Devices
 Signaling or Test Display Devices
 Assistive Listening Devices