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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
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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 LOSSAcoustics 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 LOSSAcoustics 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 ISNOISE 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
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
TINNITUSDIFFERENTIAL DIAGNOSIS Two types: 1. Objective tinnitus -others hear it too 2. Subjective tinnitus -patient only hears it
OBJECTIVE TINNITUS • Patulous eustachian tube: • Muscular: • Stapedius spasm: myoclonus of the stapedius causes contractions of the TM seen with impedance bridge or otoscope • Palatal myoclonus: myoclonus of the palate • TMJ: 28% of those with TMJ syndrome have tinnitus
TINNITUSOBJECTIVE • 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 jugularbulb
TINNITUSTESTS 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
TINNITUSTREATMENT • Tinnitus may be eliminated if a specific cause is found: • l. Tumors: glomus, AN, • 2. Infections, wax • Meniere’s disease: • TMJ disorder • Otosclerosis • Vascular malformations • Medications
TINNITUSTREATMENT • 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 • 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 LOSSCOMMON 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 30Whisper, quiet library 40 Refrigerator hum 50 Rainfall 60Normal 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 LOSSOSHA (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 LOSSHEARING 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 TREATMENTAs 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
TINNITUSTREATMENT Miscellaneus approaches: l. Hearing aids: 2. Maskers 3. Psychological help: 4. Self help 5. TRT (Tinnitus Retraining Therapy):
TINNITUSTREATMENT Non-drug treatments: dubious l. Acupuncture: 2. Electrical stimulation: 3. Electromagnetic stimulation 4. Magnetic stimulation: 5. Ultrasound 6. Surgery