Intro to Hearing Aids - FINAL EXAM

What are the frequency ranges for acoustic plumbing?

What are the frequency ranges for acoustic plumbing?

• vents: up to 1500 Hz (lows)

• dampers: 750-3000 or 4000 Hz (mids)

• acoustic horns: 1500 and above (highs)

Short answer: why is speech-based stimuli better to use for verification of HAs than swept pure tones?

• swept pure tones are sometimes perceived as feedback, thus, the gain gets reduced

• speech mapping (Carrot Story/Intl Speech Signal) has all the sounds of speech in it to ensure they can all be measured, adjusted, and affected with the HAs' Rx formulae

• speech is always, always, ALWAYS better because humans are not robots!

Short answer: give the definition and rationale for the half-gain rule.

• intended for fitting linear HAs, as it provides the same gain for all inputs

• used to raise speech to MCLs (which is halfway between the HTLs and LDLs)

• really only ideal for flat (linear) losses

REUG

• real ear unaided gain

• measures the open, natural ear canal

REAG

• real ear aided gain

• measures HA in place and on

REIG

• real ear insertion gain

• the difference value between REAG - REUG

• use: verifies Rx targets

REOG

• real ear occluded gain

• measures HA in place and OFF

REUR

• real ear unaided response

• measures the open, natural ear canal

REOR

• real ear occluded response

• measures the HA in place and OFF

REAR

• real ear aided response

• measures output when aided

• use: verifies Rx targets

REAR 85/90

• measures REAR with an 85/90 dB SPL input

• use: determines real ear MPO for the HA, based on unaided LDL measures

Define gain.

• a difference measure between the input and what's happening in the real ear

Define response.

• an absolute measure

• the output of the HA in the real ear

What are the linear Rx formulae?

• 1/2 gain rule

• Rx of Gain and Output (POGO, POGO II)

• Nat'l Acoustics Lab (NAL, NAL-R, NAL-RP)

• Desired Sensation Level (DSL)

What are the non-linear Rx formulae?

• Desired Sensation Level (DSLv4.0 and v5.0)

• Nat'l Acoustics Lab Non-Linear 1 and 2 (NAL-NL1, NAL-NL2)

What describes the DSLv4.0 and v5.0 Rx formulae?

• more emphasis on high fx

• fewer correction factors (tonality, gender, etc.)

• has more gain

• ALWAYS used for children

What describes the NAL-NL1 and NAL-NL2?

• has less gain than the DSLv5.0

• has many correction factors (tonality, gender, etc.)

What are the three goals of amplification?

• make soft sounds audible

• make average sounds comfortable

• make loud sounds tolerable

What are 3 rules for target matching in Rx verification?

1. Dillon's rule

2. Venema's rule

3. Ricketts' rule

Define Dillon's rule regarding Rx verification.

measurements should be within +/- 5 dB from the target in the 250-4000 Hz range, IF the formula has evidence to support it

Define Venema's rule regarding Rx verification.

measurements should be at or slightly above target in the 500-4000 Hz range

Define Ricketts' rule regarding Rx verification.

• for 250-2000 Hz, measurements should +/- 5 dB

• for 3000 and 4000 Hz, measurements should +/- 8 dB

What is RETSPL?

• real ear to sound pressure level (the measurement of audiometer to coupler)

• converts HL LDLs to 2cc values (for earphones)

What is RECD?

• real ear to coupler difference

• the 2cc coupler response (output) MINUS the real ear response of the same earphone

• use: helps determine max output in the ear canal

What is REDD?

• real ear to dial difference

• a difference in dB between SPL of TM from the audiometer dial

• use: derive ear canal SPL display of audiometric and Rx output data for REAR verification

Short answer: Why are AuDs who don't perform verification measures in violation of their code of ethics?

• Texas licensure REQUIRES it..."verify appropriate fit...may include real-ear measures, functional gain measures, etc."

• nationally, "best practice methods" are a must at all times!!

Define verification.

• tasks completed by an AuD to ensure a well-fitting HA

• real-ear measures

• are we building the system right?

• does the HA act in the way we'd expect?

Define validation.

• assessments made by patients using outcome measures to determine if HAs have made a difference in their lives

• are we building the RIGHT system?

• is this assisting the patient in the way we'd expect?

Short answer: Define directionality, and explain why it may improve speech understanding in background noise.

Clinical complaint: voice sounds hollow, boomy, speaking in a barrel. Possible problems and solutions?

1. earmold/shell is excessively blocking the ear canal = increase area and/or decrease the vent length; electrically cancel the occlusion-generated sounds

2. HA distorts when the patient speaks = source-to-ear distance is too short; SPL level of own voice may be high; compare their voice to the AuD's loud voice to see if same issues occur; they may want less gain for their own voice

3. HA is excessively amplifying low fx sounds = patient may have forgotten what their own voice sounds like

Clinical complaint: volume control can't be increased w/o whistling (occurs during chewing, talking, wearing hats, etc.)Possible problems and solutions?

1.HA makes a ringing noise when certain sounds occur (problem is feedback oscillation) = make sure REAG has no excessive peaks, decrease vent size, change from closed to open dome, decrease high fx again or the high fx compression ratio, or increase the high fx compression threshold in the relevant channel

• be aware that these 3 things may affect speech intelligibility or sound quality

2. other solutions = remake/recoat ear mold (takes extra time and expense); change to HA with a more effective feedback system

Clinical complaints about Tonal Quality can be...

1. excessive high fx = sounds shrill, harsh, sharp, metallic, and tinny

2. excessive low fx = sounds muffled, unclear, dull

What are some solutions for clinical complaints regarding Tonal Quality?

• change the balance of the high and low fx gain

• can involve 3 complications

1. excessive peaks in a response with balanced and high fx gain

2. complaints may only be for low level or high level inputs

3. pts may not be used to high or low sounds that they've missed for a long time

What are some possible complaints regarding Noise, Clarity, and Loudness?

1. excessive amplification of noise

2. inadequate speech clarity

3. inappropriate loudness of wanted signals

What is important to know regarding clinical complaints regarding Noise, Clarity, and Loudness?

know whether the pt is unhappy with the loudness of weak, medium, and loud sounds

Possible problems and their solutions associated with complaints about Noise, Clarity, and Loudness.

1. HA is noisy in quiet places = internal noise may be amplified in quiet; external noise means patient may not realize that others can hear these sounds

2. soft speech in quiet places can't be heard = provide more gain to low level sounds

3. HA is sometimes too loud and needs to be shut off = decrease OSPL90 or improve input-output characteristics (compression ratios)

4. background noise makes difficult for understanding speech = check if noise reduction is working or suggest directional/remote mics

5. people in background are easier to understand than those close by (close speech may trigger higher compression) = adjust output, use compression limiting, have an excessively low or high compression ratio

Short answer: Explain verification procedures as you would to a patient.

Ok, so today is all about you! I am going to make sure your hearing aids are working correctly according to your hearing loss. I'll put them in this test box, and then make some adjustments on how they pick up sound. All these changes are based off your audiogram that I've put into the computer.

List 5 device related topics that should be covered within HA orientation

1. insertion/removal

2. HA features

3. battery specs

4. warranty info

5. care and maintenance

List 5 effective communication strategies.

1. reduce background noise

2. speak at normal/slower pace

3. speak in short, clear sentences

4. talk face-to-face

5. ensure good lighting (avoid shadows)

Advantages of the COSI validation measure

• most patient specific/focuses on pt needs

• helps guide treatment

• quick

• provides specifics on what has worked, and what hasn't D

Disadvantages of the COSI validation measure

• norms not available

• too much variability

ECHO validation measure advantages

• short

• has norms

• unique for expectationsE

ECHO validation measure disadvantages

• complicated to score

SADL validation measure advantages

• short

• has norms

• unique for satisfactionS

SADL validation measure disadvantages

• hard to score

COAT validation measure advantages

• easy to administer and interpret

• takes 10 minutes to do

• can function as a basis for counseling during HA selectionC

COAT validation measure disadvantages

• no norms

APHAB advantages

• has reversed items for validity of responses

• measures pre and post-intervention

• available in 15+ languages

APHAB disadvantages

• hard to score

• steps not equidistant

• may be difficult for elderly to give exact answers

• confusion between answering for both unaided and aided conditions at the same time

IOI-HA advantages

• quick administration

• easy to score

• quick check on key areas post-HA fitting

IOI-HA disadvantages

• post-HA fitting measure only

• may lack specificity in determining HA outcomes

PHAST advantages

• takes 10 minutes to administer and score

• results used to ID HA tasks the pt needs further instruction/counseling

PHAST disadvantages

• only measures practical skills

• doesn't take patient's feelings into account

FM system advantages

• used inside and outside

• has mobility

• broadcast possible to an unlimited amount of FM receivers

• access is easy through built-in receivers in HAs (can also be accomplished through DAI)

FM system disadvantages

• expensive $$$

• requires frequent maintenance

• doesn't ensure privacy

infrared system advantages

• transmits high quality signal to listeners

• doesn't limit seating (provided there is a direct line of sight)

• privacy is assured (infrared can't pass through walls)

Infrared system disadvantages

• expensive (each listener needs a receiver)

• affected by sunlight which degrades the signal

• has possibility of light reflecting off of the room's surfaces

• requires more light emitting diodes (sensors) in larger roomsI

Induction loop system advantages

• provide accessibility to listeners with telecoil-equipped HAs/CIs

• allows for freedom of movement within the loop

• available for relatively low expense

Induction loop system disadvantages

• requires telecoil in receiver

• subject to interference from a variety of sources (60-cycle hum, fluorescent lights)

• subject to spill-over from adjacent rooms

Short answer: How are children and infants different form adults in their rehab characteristics?

a. auditory closure and filling in blanks b. importance of audibility for inaudible sounds c. listening demands d. role of the patient's family/caregiver

Explain auditory closure and filling in blanks.

• children are learning language

• they can't fill in blanks for inaudible sounds like adults can

Explain the importance of audibility for speech development in children.

• children spend more time listening to other children and women (higher fx than male speech)

• thus, it's important to make high fx cues audible

• children have to be able to use info acquired with amplified hearing and processed sound (ALL speech cues must be made audible!!)E

Explain listening demands regarding children.

• children have MANY MORE listening demands than adults (especially in difficult listening situations)

• Rx targets may specify greater output in quiet situations

• remember the 2nd grade landmark = goes from learning to read, to reading to learn

Explain the role of the pediatric patient's family/caregiver.

• children's HA use is often heavily mediated by their caregiver

• thus, parents/caregivers have to know the ins and outs of HA maintenance and use

Short answer: Why are BTEs the choice HA style for peds patients?

• Children are CONSTANTLY growing, thus, there's no point in custom devices because they'd have to be remade

• adolescent children could probably use a RIC/RITE

• BTEs are extremely durable for everything a child does (running, jumping, etc.)

• BTEs can be used with a variety of HAT systems for educational and social settings

• BTEs are also big enough to have indicator lights, tamper-proof doors, etc.

What is a HAT system?

• hearing assistive technology

• NOT a medical deviceWh

What are the 4 communicative needs a HAT system addresses?

1. live, face-to-face communication

2. broadcasting and other electronic media

3. telephone conversation

4. sensitivity to alerting signals and environmental stimuli (e.g. doorbells, smoke alarms, timers, crying kid, etc.)

What are some situations where HAT systems can be used?

1. at home

2. in the community

3. school

What are some examples of personal HAT systems?

• personal FM (common for school)

• hardwired systems

• telephone amplifier

• telecoil

• telecommunication devices for the deaf (TDD)

• television

• alerting devices

What are some examples of large area HAT systems?

• infrared system

• induction loopW

What are some HAT systems that can help with telephone communication?

• Whistle-stop (goes over phone receiver)

• inline amplifier (amplifies sound signals by plugging into phone)

• amplified telephone (captioned and/or amplified)

• portable amplifier

• replacement handset

• TDDWh

What are some HAT systems that can help with environmental awareness of sounds?

• Ring Max (helps with auditory alerts)

• Shake Awake

• visual and auditory smoke detectors

• Lifetone HL (bedside fire alarm and clock)

• phone flasher

• wireless flasherW

What are some HAT systems that can help with face-to-face communication/television listening?

• pocket talker