Aural Rehabilitation Audiology Appointment Notes
Aural Rehabilitation Audiology Appointment
Steps to a Hearing Evaluation
- Case history
- Otoscopy
- Middle ear testing
- Tympanometry
- Acoustic reflex
- Audiometry
- Pure tone testing
- Speech testing
- Otoacoustic Emissions (OAEs)
- Auditory Brainstem Response (ABR)
Intervention for Hearing Loss
- If hearing loss is present, intervention is the next step.
- Audiologic rehabilitation:
- For adults or those who need to modify communication skills due to acquired hearing impairments.
- Audiologic habilitation:
- For children or those learning to use speech and language skills for the first time.
- Intervention depends on several factors:
- Social impacts
- Psychological impacts
- Communication impacts
- Degree of hearing loss: Increased hearing loss = increased difficulty understanding speech.
- Acceptance of hearing loss.
- Motivation for seeking assistance.
- Cosmetic concerns.
Amplification
- Wearable Devices:
- Hearing Aids
- FM systems
- Assistive listening devices
- Over-the-counter hearing aids
- Implantable devices
- Osseointegrated devices (BAHA)
- Cochlear Implant (CI)
History of Hearing Amplification
- Ear Trumpet (17th Century) - non-electronic
- Vactuphone (1920s)
- Transistors (1950s) - led to concealed body aids and eyeglass-mounted hearing aids
- Analog hearing aids (1960s)
- Digital hearing aids (1990s - present)
Hearing Aid Styles
- Completely-in-canal (CIC)
- In-the-canal (ITC)
- In-the-ear (ITE)
- Behind-the-ear (BTE)
- Receiver-in-canal (RIC) / Receiver-in-the-ear (RITE)
- BTE open fit
Hearing Aids
- Devices that fit on or in the ear, designed to amplify sound reaching the ear drum.
- Deliver sound through normal air conduction pathway.
- Increase sound intensity in the frequency region of hearing loss.
- Functions like an EQ on a car stereo, boosting certain frequencies (called gain).
- Usually can restore conductive hearing loss to normal range.
- Usually cannot restore sensorineural hearing loss to normal range.
Hearing Aid Selection
- Factors to consider:
- Type & degree of hearing loss (biggest factor)
- Cosmetic preferences
- Binaural/monaural fitting
- Prior use/experience
- Age
- Environment of use
- Controls/compatibility
- Different levels of technology (Basic, middle, premium)
- Bluetooth accessibility
Hearing Aid Fitting
- Audiologist uses expertise and patient's desires to make a selection.
- Once aid arrives, audiologist performs electroacoustic analysis.
- At initial fitting, audiologist inputs patient's hearing thresholds.
- Computer program adjusts the output gain accordingly.
- Usually set lower than recommended on first fitting.
- Aids are placed on patient and turned on.
- Audiologist can (should) perform real-ear measurements.
- Small microphone (probe-tip) is placed in the ear.
- Gives reading of what amplification is actually reaching the ear drum.
- Audiologist makes adjustments according to patient comfort.
Follow-up Appointments
- Audiologist can see how much patient has used the aids (data logging).
- Can make adjustments: increase/decrease gain.
- Design programs for certain listening environments.
- Standard maintenance & upkeep:
- Cleaning
- Replacing worn out parts
Bone-Anchored Hearing Aids (BAHA)
- For severe conductive loss where the cochlea is functioning normally.
- Prosthetic device surgically implanted into the skull (abutment).
- Bone-conduction hearing aid is attached to the abutment.
- Bypasses the outer & middle ear, stimulates the inner ear via vibrations in the skull.
- Can also be used for single-sided deafness: transmits sound across the skull to functioning cochlea.
- Ideal candidates:
- Microtia
- Conductive hearing loss
- Mild or moderate SNHL
Research on Hearing Aid Users
- Socialize more
- Perform better in school (younger people)
- Reduce cognitive decline (older people)
- Reduce impact of tinnitus
Why Hearing Aids Aren’t More Popular
- Only about 20% of people who need them seek them out.
- Usually a period of 7-10 years between needing them and getting them.
- More than 80% of users are satisfied with them.
- Fit, comfort, maintenance can be a hassle.
- Sometimes have unrealistic expectations.
- Cost: range from 2000 to 5000 for a pair.
- Psychological factors, social stigma, cosmetic appearance
Over-the-Counter (OTC) Hearing Aids
- Law passed in October 2022 made OTC hearing aids available to the public.
- Available at Walgreens, CVS, Best Buy, online.
- Price range: 200-1000
- Available for adults 18+ years old.
- No audiologist involved in purchase.
- For perceived mild to moderate hearing loss.
- Users can control and program HAs themselves.
- Most include a smartphone app.
- Not included: Audiologist's expertise (programming, maintenance, etc.)
Cochlear Implants (CI)
- Implantable device that electrically stimulates the auditory nerve.
- Bypasses the outer, middle, and inner ear and stimulates the nerve directly.
- Provides sound input for people with moderate to profound sensorineural hearing loss.
- Doesn't “cure” hearing loss, it works around it.
CI Candidacy Criteria
- Adults (18+):
- Moderate to profound sensorineural hearing loss in both ears.
- Limited benefit from amplification: <50% sentence recognition in the ear to be implanted and <60% in the opposite ear or binaurally.
- Children (2-7):
- Severe to profound sensorineural hearing loss in both ears.
- Limited benefit from binaural amplification.
- Multisyllabic Lexical Neighborhood Test (MLNT) or Lexical Neighborhood Test (LNT) scores <30%.
- Children (9-24 months):
- Profound sensorineural hearing loss in both ears.
- Limited benefit from binaural amplification.
CI Surgery
- Hole drilled in the mastoid bone behind the ear.
- Internal receiver placed under the skin.
- Electrode inserted through middle ear space into the cochlea, usually through the round window.
- Electrode threaded upward along the cochlear spiral.
After CI Surgery
- Sound processor converts external sound into electrical impulses.
- Transmitted from the external processor to the internal receiver.
- Receiver transmits them to the electrode array in the cochlea.
- Electrode array bypasses the hair cells and stimulates the auditory nerve directly.
Benefits of a CI
- Post-lingual adults (adults that have spoken language):
- Pre-lingual children:
- Typically 6 months or older.
- Younger is better: greater chance for success.
- Auditory input at a young age is critical for spoken language development.
- Early implantation can lead to near-normal spoken language skills.
- Adults deaf most of their life can get a CI but are unlikely to develop speech understanding or production. Can still hear sounds.