Auditory Problems

How many dB is normal hearing?

0-15 dB

Conditions in middle and outer ear; impairs the transmission of sound

Conductive hearing loss

Causes of conductive hearing loss

• Otitis media with effusion

• Impacted cerumen (ear wax)

• Perforation of the tympanic membrane

• Otosclerosis

• Narrowing of the external auditory canal

Impairment of function of the inner ear or vestibulocochlear nerve (VIII)

Sensorineural hearing loss

What are clinical manifestations of sensorineural hearing loss?

• Ability to hear sound, but not understand speech

• Ability to hear high-pitched sounds

• Sounds become muffled and difficult to understand

What are causes of sensorineural hearing loss?

• Aging (presbycusis)

• Systemic infections

• Paget’s disease of the bone

• DM

• Bacterial meningitis

• Trauma and noise trauma over time

• Meniere’s disease

• Ototoxicity or ototoxic drugs

Hearing loss caused by emotional and psychological factors; physical reasons may not be identified

Central and functional hearing loss

What are causes of central and functional hearing loss?

• Hx of deafness in the family

• Refer patient to psychological counseling and speech therapy as needed

Combination of both conductive and sensorineural hearing loss

Mixed hearing loss

Early signs of hearing loss include:

• Answering questions inappropriately

• Not responding to questions when not looking at the speaker

• Asking others to speak up

• Showing irritability with others who do not speak up

• Answering questions inappropriately

• Not responding to questions when not looking at the speaker

• Asking others to speak up

• Showing irritability with others who do not speak up

• Bilateral tinnitus

These are clinical manifestations of what condition?

Early signs of hearing loss

What are behaviors that suggest hearing loss?

• Straining to hear

• Cupping ear

• Reading lips

• Increased sensitivity to slight increases in noise level

• Often patient is unaware of minimal hearing loss

• Rapid loss of hearing

• Loss is usally in one ear

• Can happen either at once or over several days

• Medical emergency → immediate evaluation of HCP

Rapid hearing loss

Cause of this disease is unknown. Symptoms include:

• Episodic vertigo

• Tinnitus

• Fluctuating sensorineural hearing loss

• Aural fullness

Meniere’s disease

• Accumulation of endolymph in membranous labyrinth (though cause is unknown)

• Usually affects only one ear

• Excess fluid and pressure → hearing and balance problems

Meniere’s disease

What symptoms in Meniere’s disease happen prior to a veritgo attack?

• Fullness in ear

• Tinnitus

• Muffled hearing

• Experience the feeling of being pulled to the ground (“drop attacks”)

Abnormal eye movements or blurred vision. Often seen as twitching of the eyeball or described as blurring of vision with head or eye movement.

Nystagmus

Person or objects moving or spinning; stimulated by head movement. Dizziness is a sensation of being off-balance.

Vertigo

First symptom of hearing loss, especially in older adults

Bilateral tinnitus

What is characteristic of a vertigo episode in Meniere’s disease?

Sudden, severe attacks of vertigo can result in NV, sweating, nystagmus, and pallor and may cause significant disability. These attacks can last for hours or days and may occur several times a year

• Vertigo caused by free-floating debris (“ear rocks”) in semicircular canal with head movements (e.g., changing positions)

• Symptoms: nystagmus, loss of balance, nausea (bothersome, but falls are rare)

• NO HEARING LOSS

Benign Paroxysmal Positional Vertigo (BPPV)

Diagnosis of BPPV

• Diagnosis: auditory and vestibular tests

• Treatment: Epley maneuver 

Moves ear debris to areas of the inner ear that are less sensitive. Can be taught to the patient. 

Epley maneuver

Treatment of Meniere’ disease

• No cure; treaments is to reduce frequency of vertigo attacks

• Acute attack (decrease vertigo and NV) → antihistamines, anticholinergics, benzos, antiemetics

• Between attacks → antihistamines, low sodium diet, limit caffeine and ETOH, vestibular exercise

• Surgery

• Gentamicin injections (damages inner ear that reduces endolymph production)

Treatment of acute attacks of Meniere’s disease

Antihistamines, anticholinergics, benzos, antiemetics

Treatment of Meniere’s disease between attacks:

• Antihistamines

• Low sodium diet

• Limit caffeine and ETOH

• Vestibular exercise

Surgical intervention for Meniere’s disease

• Decompression

• Vestibular nerve section

• Ablation of labyrinth (unilateral disease)

Patient education for Meniere’s disease

• Protection for injury between attacks

  • Lie or sit with onset of dizziness

  • Home safety (fall precautions)

  • No underwater swimming

  • Avoid high places

• Practice balance therapy exercises and vestibular exercises

• Limit caffeine and ETOH + low sodium diet

Diagnostic tests for Meniere’s disease

• Audiogram → Assesses low frequency sensorineural hearing loss

• Spontaneous vertigo on two occasions

• Abnormal vestibualr tests

• Glycerol test

• Perception of sound that originates in the head

• “ringing in ears” or “head noise”

• Bilateral tinnitus may be first symptom of hearing loss, especially in older adults

  • May be soft or loud, high pitched or low pitched

Tinnitus

What can cause tinnitus?

• Noise exposure

• More than 200 drugs cause tinnitus

• TMJ, stroke, head and neck injuries

• Aging

Age-related hearing loss that causes:

• Loss of peripheral auditory sensitivity

• Can hear vowels; not consonants

• Causes decreased ability to understand speech

• Can lead to confusion, embarrassment, isolation

Presbycusis

Gerontological considerations for hearing loss

• Presbycusis—sensorineural hearing loss due to aging

• Tinnitus—ringing in ears

  • Reduced transmission of sound— atrophy of cerumen glands; dry earwax

• Atrophy of vestibular structures 

  • Decline in balance, slow motor responses, musculoskeletal limitations

Most with hearing loss of 90+ dB are →

Congenitally deaf

• Problem in CNS (brain) causes inability to interpret sound/speech

• Usually cases of deafness within family

Central hearing loss

• Emotional or psychologic causes

• Lack of hearing or response to pure-tone subjective hearing tests; no physical reason identified

• Psychologic counseling may help

Functional hearing loss

• Affects external and middle ear

• Decrease sound intensity and/or distortion

• Earwax, otitis media, TM perforation, otosclerosis, allergies, benign tumors

• Patient speaks softly; may hear better in noisy environment

Conductive hearing loss

• Congenital and hereditary factors, noise exposure, aging (presbycusis), Ménière’s disease, trauma, ototoxicity

• Can hear sound

• Difficulty understanding speech

• Others do not understand the problem

• Hearing aid makes sounds louder but not clearer

Sensorineural hearing loss

Health promotion for hearing loss and deafness

• Environmental noise control 

  • Noise is most preventable cause of hearing loss

  • Acoustic trauma destroys hair cells of organ of Corti

  • Noise-induced hearing loss:

    • How loud, how close you are, how long you listen