Module 10 Flashcards
Decision-making parameters for selection of basic electro acoustic characteristics of HA
-How much gain will be provided at each frequency?
-Will the amount of gain vary dependant of the input (i.e. WDRC or linear processing?)
-What will the maximum power output (MPO) of the hearing aid be (comfort and safety)?
What is dynamic range and how large can it be in normal hearing listeners?
Area in dB HL between detection and level of discomfort. In normal hearing sensitivity listeners, dynamic range can be upwards of 100 dB
How does dynamic range vary with SNHL, CHL, and mixed loss?
-SNHL: dynamic range is REDUCED
-CHL: dynamic range is generally UNCHANGED
-Mixed: dynamic range is VARIABLE
When should you not select a hearing aid with volume control?
-Patients with dexterity issues may not be able to manipulate a VC button on the devices themselves or accidentally adjust
-Patients who prefer to have a “fully automatic” listening experience
-Patients with cognitive issues
-Pediatric patients
What are telecoils (t-coils)?
-Used as an alternative way to introduce a sound signal to a hearing aid wirelessly
-The t-coil picks up sound through an electromagnetic induction signal to wirelessly send directly to the hearing aid
-Generally used for wireless hearing in a public venue or with connection to landline phones (“T-rating”)
-Look for “T” on model description
Telecoils: Public Venue
Loop systems are used: provide enormous benefits when competing with background noise or distance. Can be in a room, area of the room, a chair, or a neck loop
Telecoils: Phone Use
-Landline telephones can be used in conjunction with telecoil
-Magnet in the receiver communicates with the telecoil (manual or automatic)
-Telecoils can prevent feedback for those with significant losses
-Placement matters to improve SNR
When to select a heard aid with telecoil
-More benefit from t-coil for patients with greater loss
-Patients who score poorly on SIN testing
-Patients who self-report difficulties in different listening areas. Can you reach out to those venues to inquire about loop systems?
Disadvantages of T-Coils
-Model potentially larger
-Patients need to learn when and how to use t-coil effectively
Should you select a hearing aid with directional microphones (DM)?
-YES (unless the instrument of choice does not have DM capability)
-There may be some listening situations where a patient either wants to override or “lock” a DM into a particular configuration
·Wheelchair users, in cars
Factors to consider when selecting a specific brand/model of HA
-Audiogram, SPIN testing
-Lifestyle
-Product’s electroacoustic parameters (i.e. is there sufficient gain, what controls are needed, what accessories are required, what coupling will be needed?)
-Manufacturer stipulations for repair, loss/damage
-Budget
