HEARING LOSS Babak Saedi otolaryngologist

How the Ear Hears Structure Outer ear  The pinna is a collector of sound wave vibrations that are sent through the external ear canal. Middle Ear  A tympanic membrane and three tiny bones, incus, malleus and stapes, move in harmony to send the vibrations into the inner ear. Inner Ear  The vibrations are changed into electrical impulses that are sent to the brain to create what we understand as “hearing.”

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Types of Hearing Loss Conductive Hearing Loss Sensorineural Hearing Loss Mixed Hearing Loss Progressive Hearing Loss

Types of Hearing Loss Conductive Definition  Loss of hearing that originates in the outer or middle ear.  A mild hearing loss is caused from the fluid buildup in the middle ear from a middle ear infection, or otitis media.

Healthy tympanic membrane Acute otitis media with fluid Chronic otitis media Otitis media with tympanic membrane hole or perforation Otitis media treatment - tympanic membrane hole or perforation with a ventilator tube in place Conductive - Tympanic Membranes

Types of Hearing Loss Sensorineural Damage in the inner ear. Usually causes a permanent hearing loss

Types of Hearing Loss Mixed  Hearing loss that involves the middle and inner ear.

CONDUCTIVE HEARING LOSS Occurs from a dysfunction of the outer or middle ear Can usually be treated with medicine or surgery A deficit of loudness only

Characteristics of Conductive Loss:  Maintain soft speaking voice  Excellent speech discrimination when speech is loud enough  Typically either low frequency or flat hearing loss (equal at all frequencies)

TREATMENT: CONDUCTIVE HEARING LOSSES  Conductive hearing losses are due to problems that occur in the outer and middle ear which are usually temporary and/or treatable with antibiotics or surgery.  For those few people who have uncorrectable conductive hearing losses, hearing aids are of significant benefit as sound remains clear if it is made loud enough.

SENSORI-NEURAL HEARING LOSSES  Dysfunction of the inner ear or auditory nerve, usually permanent and untreatable  Results in loudness deficit and distorted hearing.  Nerve endings in cochlea or nerve pathways are damaged.  Message does not effectively reach the brain.  Middle ear structures are intact.

CAUSES OF SENSORI-NEURAL HEARING LOSS:  Genetics/Congenital  Disease Mumps, Measles Meningitis, CMV  Ototoxic drugs  Head trauma  Presbycusis  Meniere’s Disease  Acoustic Neuroma  Ototoxin Exposure  Noise Exposure: Prolonged exposure to hazardous noise causes hearing loss by the physical destruction of the hair cells in the cochlea.

Characteristics of NIHL: (noise induced hearing loss)  Loss can be sudden, as with acoustic trauma from an explosion.  More often a gradual onset that may go unnoticed. NIHL also known as noise induced permanent threshold shift (NIPTS), typically takes years of exposure, gradual erosion of hearing that eventually affects communication.

Characteristics of SNHL, con’t  Amount of loss varies from person to person  Risk of noise-induced progression stops if no longer in noise exposed, but aging invariably worsens loss For most, aging effects aren’t significant before age 50+

Audiogram – Picture of Hearing Levels Normal 0-15 Mild Moderate Severe Profound

Types of Hearing Loss Progressive  A gradual and increasing loss of hearing over time  Immediate medical referral and treatment is necessary

Amplification & Assistive Devices  Hearing Aids cannot fix a hearing loss  Hearing Aids only amplifies incoming sound for the child  Types of Hearing Aids

Teaching Strategies Acoustics  Noise Pollution Noise enters the room  Hallways  Heating and air conditioning vents  Outside noises – mowing, playground  Other classrooms Noise inside the room  Students talking  Rustling paper  Pencil tapping  Chair movements

cochlea Pinna (aruricle) external ear canal Tympanic membrane malleusincusstapes Cochlea & hair cells Ear Diagram Outer Ear Middle Ear Inner Ear

POINTS TO REMEMBER ABOUT HEARING LOSS  You can’t fix a hearing loss  Any hearing loss – even MILD – impact children’s learning  Improving classroom acoustics will improve learning for hearing and hearing impaired children  If children can’t hear, they can’t learn

Questions?

Success in Life Begins With Hearing!