Download tinnitus & hearing loss

HEARING LOSS
AND
TINNITUS
Charles Stewart
HEARING LOSS
Hearing loss to many is an insignificant disability
Why is this?
It is invisible
usually painless
It is a hurt that does not show
To the profoundly deaf, they live in a world
of silence, the emotional pain is devastating
HEARING LOSS
Hearing loss is important!

1 in 10 in the U.S. have some H.L.

1 in 100 has extreme difficulty with
understanding speech
The cost to society is in the billions per year
WE NEED TO BE MORE AWARE,
MORE SYMPOTHETIC, MORE
HELPFUL TO THOSE WITH HEARING
LOSS
HEARING LOSS
Types of hearing loss:

Conductive hearing loss

Sensorineural hearing loss
Sensory (cochlea)
Neural (8th nerve)

Mixed hearing loss

Functional hearing loss: non-organic
HEARING LOSS
Acoustics
Intensity of sound: loudness, measured in dB
Frequency of sound: Pitch, measured in Hz or
cps
Pure tone: single frequency sound, as
audiogram, rare in nature
Complex sound: more than one frequency;
noise is a complex sound
HEARING LOSS
Acoustics
Decibel scale (db): logarithmic scale, to measure
intensity of sound; dB=log of a ratio of two
sounds: reference sound & sound being described
Stimulus levels are stated with reference levels:
SPL: sound pressure level; .0002 dynes/cm2
HL: Hearing level; 0 dB HL on audiometer
SL: Sensation level
Hearing range: 10-20,000 cps; Intensity range 0-120
HEARING IMPAIRED: anyone with hearing loss
DEAF: anyone with profound SNHL
Categorizing hearing loss:
normal: 0-25 dB
mild H.L.: 26-45 dB
Mod.H.L.: 46-70 dB
Severe H.L.: 71-90 dB
Profound H.L.: >90 dB
PURE TONE AUDIOMETRY

Air conduction: actual hearing level: outer,
middle, inner ear

Bone conduction: Potential hearing level, inner
ear function

Conductive hearing loss: Difference between air
& bone conduction threshold, the ABG
AUDIOGRAM
Screening audiogram should include:
l. Pure-tone evaluation: bone/ air
threshold
2. Speech receptive threshold: (SRT)
3. Speech discrimination score (SDS)
THE MAJOR CAUSE OF
SENSORINEURAL HEARING LOSS IS
NOISE EXPOSURE
The cause of the hearing loss is :
l. Acoustic trauma:
single high intensity
sound, causing a conductive &/or
SNHL
2. Noise induced hearing loss: gradual
loss from prolonged or repetitious
noise exposure
EFFECTS OF NOISE EXPOSURE
Hair cell swelling (temporary threshold shift)
Hair cell destruction (permanent threshold shift)
CONTROL OF NOISE EXPOSURE
Environmental control:
reduce noise
Personal protection:
ear protection (ear plugs)
job rotation
job reassignment
test hearing periodically (annually)
TYPES OF HEARING LOSS THAT RAISE
AN INDEX OF SUSPICION
Sudden hearing loss in healthy individuals
Gradual hearing loss
Fluctuating hearing loss
Pronounced buzzing or roaring tinnitus
What suggestive clues or symptoms
does a person undergoing noise
induced hearing loss have?
Difficulty communicating at work
Head noise at work
Temporary loss of hearing
WHAT IS NEW FOR THE TREATMENT OF
HEARING LOSS?
BAHA
COCHLEAR IMPLANTS
BAHA
COCHLEAR IMPLANTS
COCHLEAR IMPLANTS
COCHLEAR IMPLANTS
TINNITUS
Definition: perception of noise in the absence of
acoustic stimulus
phantom auditory perception
Incidence: 40 million Americans have it
75% are not bothered by it
25% it interferes with their daily life
TINNITUS
DIFFERENTIAL DIAGNOSIS
Two types:
1. Objective tinnitus -others hear it too
2. Subjective tinnitus -patient only hears it
OBJECTIVE TINNITUS
l. Patulous eustachian tube:
2. Muscular:
1. Stapedius spasm: myoclonus of the stapedius causes
contractions of the TM seen with impedance bridge or
otoscope
2. Palatal myoclonus: myoclonus of the palate
3. TMJ: 28% of those with TMJ syndrome have tinnitus
TINNITUS
OBJECTIVE
3. Vascular
 AV shunts: Glomus tympanicum/jugulare tumour
Pulsating tinnitus, hearing loss
Bluish mass behind ear drum
 Arteriovenous malformation: Dxn. with MRI, MRA,
Angiogram; Tmt. Embolization
 Arterial bruits:
Aberrant carotid artery
Persistent stapedial artery
Venous hum:
HBP; Hyper/hypothyroidism; high jugular bulb
TINNITUS
TESTS
Audiogram, tympanogram: ENG & posturography not usually
necessary
Lumbar puncture: after CT, those with papillodema
BAER, ECOG:
MRI, MRA, CT
Blood tests: ANA,B12,FTA,ESR,SMA-24
Glucose,TSH,antimicrosomal antibodies
TINNITUS
TREATMENT
Tinnitus may be eliminated if a specific cause is found:
l. Tumors: glomus, AN,
2. Infections, wax
3. Meniere’s disease:
4. TMJ disorder
5. Otosclerosis
6. Vascular malformations
7. Medications
TINNITUS
TREATMENT
Medications:
 NSAIDS (motrin, naproxen, relafen, etc)
 ASA & other salicylates
 Lasix & other “loop” diuretics
 “mycin” antibiotics such as vancomycin( rarely macrolides as
azithromycin)
 Quinine
 Chemotherapy drugs as cis-platin
 Rarely, SSRI antidepressants as Paxil
SUBJECTIVE TINNITUS
l. Otologic:

Noise induced hearing loss

Presbycusis

Otitis media with effusion

Otosclerosis

Meniere’s disease

Cerumen

Foreign body against tympanic membrane
SUBJECTIVE TINNITUS
2. Drugs:
 ASA
 NSAIDS
 Aminoglycosides
 Antidepressants
 Heavy metal
3. Metabolic
 Vitamin A/B deficiency
 Hyperlipidemia
SUBJECTIVE TINNITUS
4. Neurologic:
Head trauma
MS
Meningitis
Acoustic neuroma
Temporal lobe tumour
5. Psychologic
Anxiety
Depression
TINNITUS & HEARING LOSS
COMMON QUESTIONS
90% of those with tinnitus have some hearing loss.
Noise exposure is the most common cause of
hearing loss & of tinnitus
Is ringing in my ear normal?
Is it possible for others to hear my tinnitus?
Can I “Toughen Up” My Ears?
How can I tell if Noise is Dangerous?
How is sound measured, and how does Frequency of
sound and Intensity of sound affect hearing
loss?
What is a Decibel?
NOISE EXPOSURE &
HEARING LOSS
How does noise cause hearing loss? Is it permanent?
What is loud?
0 dB faintest sound heard by human ear
30 Whisper, quiet library
40 Refrigerator hum
50 Rainfall
60 Normal conversation, typewriter, sewing machine, truck traffic
70 Washing machine
85 average traffic
95 MRI
100 Blow dryer, subway train,chainsaw, snowmobile
115 Sandblasting, rock concert, auto horn, screaming child
130 Jack hammer, jet engine plane
140 Shotgun blast, airbag deployment, firecracker, pain is experienced
in unprotected ears
TINNITUS & HEARING LOSS
Why has hearing loss increased significantly in young
people? Loud rock music along with the use of earphones with
portable radios
Can noise affect more than my hearing?
Tinnitus commonly occurs after noise exposure, and may
be permanent
Who should wear hearing protectors?
What are the laws for on the job?
TINNITUS &
HEARING LOSS
OSHA (Occupational Safety & Health Administration)
Guidelines
What is permissible Noise Level Exposure?
Hours per day
Sound level
8
90 dB
4
95 dB
2
100 dB
1
105 dB
.5
110 dB
85 dB or higher more than 8 hrs. requires hearing
conservation programs to protect workers.
TINNITUS & HEARING LOSS
What does OSHA recommend for Hearing Conservation?
l. Hearing protection devices:
2. Education: Sound less than 80 dB is unlikely to cause
hearing loss.
Over 85 dB a One time exposure or continuous
noise may cause temporary threshold shift, usually
disappears in 16- 48 hrs. after exposure.
3. Noise exposure for unprotected ear is 115 dB for 15
min/day (rock concert 115-120 dB)
4. Noise above 140 dB is not permitted unprotected
TINNITUS & HEARING LOSS
HEARING CONSERVATION TIPS
Be conscious of environmental noise: 3 foot rule
Wear earplugs at the movies, ask the manager to turn
the volume down
Wear earplugs at amusement parks, concerts
Wear earplugs or earmuffs using power lawn mower,
vacuum, power tools
Read labels on appliances, toys that generate sounds
TINNITUS & HEARING LOSS
How effective are hearing protectors?
Earplugs & earmuffs: are about equally effective, reduce noise
15-30 dB. Earplugs are better for low frequency sounds, earmuffs for
high frequency sounds
Combined use of earplugs & earmuffs: adds 10-15 dB more
protection, should be used if noise is above 105 dB
Can I get protection stuffing my ears with cotton?
Cotton reduces noise by 7dB
Common problems of Hearing Protectors: ½ of workers,
get ½ the needed protection because they are not worn continuously &
are poorly fit. 7 hrs. of protection is only 9 dB of protection
How do I know I’m getting protection? Your own voice is
louder & deeper
TINNITUS & HEARING LOSS
Can I understand other people & hear machinery well enough
with hearing protectors? They enhance speech discrimination in very
noisy places. Those with SNHL may have reduced ability to
understand normal conversation. Workers adjust to the lower level of
noise of machinery & still can detect problems.
How can I tell if my hearing is already damaged?
People seem to mumble, difficulty understanding, need people to
repeat frequently, & tinnitus is present
Hearing loss is painless, invisible & comes on slowly
Only sure way to tell is by a hearing test
TINNITUS
TREATMENT
As of 4/2002 the National Library of Medicine’s search
engine revealed 3900 research articles on tinnitus since
1966
What do you do if you have tinnitus & no specific cause?
l. Avoid noise exposure
2. Avoid stimulants, coffee, tea, coke, nicotine
3. Decrease salt intake (hydrops)
4. Avoid fatique, get adequate rest, daily exercise
5. Avoid ototoxic drugs, as ASA, non-steroidals, quinine
preparations
6. Balanced diet, normal amts. Of fruits & vegetables
TINNITUS
TREATMENT
Miscellaneus approaches:
l. Hearing aids:
2. Maskers
3. Psychological help:
4. Self help
5. TRT (Tinnitus Retraining Therapy):
TINNITUS
TREATMENT
Non-drug treatments: dubious
l. Acupuncture:
2. Electrical stimulation:
3. Electromagnetic stimulation
4. Magnetic stimulation:
5. Ultrasound
6. Surgery