Module 12

Question 1

Real-ear unaided response (REUR)

Answer 1

-REUR is the SPL, across frequencies, measured in an open and unaided ear canal for a signal that is delivered
-Variability in this measure across patients due to unique shape of their ear canal

Question 2

What is the typical adult resonance?

Answer 2

Increase in SPL usually between 1500-7000 Hz, with a peal nearing 2700-3000 Hz

Question 3

Real-ear unaided gain (REUG)

Answer 3

The gain or “boost” in sound provided by the pinna and ear canal itself when un-occluded (typically 10-20 dB of gain)

Question 4

How to measure REUR & REUG

Answer 4

-Otoscopic exam
-Probe tube is placed in the ear canal, placed to approximately 5 mm of the TM (black marker to inter-tragal notch)
-Patient is placed in front of the verification equipment speaker
-Select and deliver a stimulus (usually broadband sound)
-Measure the REUR/REUG

Question 5

Real-ear aided response (REAR)

Answer 5

-A REAR looks at the total response of the hearing aid delivered in the ear canal, taking into account the gain provided by the hearing aid and the patient’s ear canal when a signal is delivered
-Measured in dB SPL

Question 6

Real-ear aided gain (REAG)

Answer 6

-A REAG looks at the total gain of the hearing aid delivered in the ear canal, taking into account the gain provided by the hearing aid and the patient’s ear canal when a signal is delivered
-REAG = difference of input and output with hearing aid active

Question 7

Real-ear insertion gain (REIG)

Answer 7

-REIG is another method of verifying the hearing aid output (in dB)
-Insertion gain = real ear AIDED response - real ear UNAIDED response

Question 8

T/F: REAR is preferred today over REIG

Answer 8

TRUE: it shows the total effect (hearing aid gain AND individual characteristics) and the performance of the hearing aid/benefit on our patient

Question 9

Real-ear occluded response (REOR)

Answer 9

-The REOR measures how the hearing aid or earmold changes the REUR when the hearing aid is in and place and is turned OFF

Question 10

Real-ear to coupler difference (RECD)

Answer 10

-Difference, as a function of frequency, between the output of the hearing aid in the ear and in coupler
-RECD takes into account unique differences in ear canals—creating a more tailored fitting
-Coupling to measure RECD may be done with an insert earphone or the patient’s earmold

Question 11

Why is achieving RECD measures on pediatric patients ideal?

Answer 11

Smaller ear canal volumes will mean higher SPL than a standard 2cc coupler

Question 12

What are some factors influencing RECD values (4)?

Answer 12

-Ear canal volume size (age dependant)
-Vents, slit leaks, open fittings
-Myringotomy tubes
-Perforations

Question 13

T/F: microphone location effect (MLE) causes slightly less gain in CIC than BTE

Answer 13

FALSE: MLE causes slightly more gain in CIC than BTE

Question 14

If we have 2cc values and wish to know the estimated real-ear equivalent (TEREO), we add the values of ___ and ___ together

Answer 14

RECD + MLE

Question 15

If we have ear canal SPL values and we wish to know the coupler equivalent, we subtract values of ___ and ___

Answer 15

RECD - MLE

Question 16

How much reserve gain do we ideally want at each frequency?

Answer 16

10-15 dB

Question 17

Why is having reserve gain important (3)?

Answer 17

-Hearing sensitivity changes (aid can be reprogrammed to meet needs)
-Volume control (accounts for listening preference)
-Minimizing distortion (aid is not working at its maximum level)

Question 18

Output Sound Pressure Level with 90 dB Input (OSPL90)

Answer 18

-How much power output is the hearing aid capable of?
-Measuring a 90 dB stimulus, across a frequency range is presented, and the output is measured in the coupler

Question 19

High frequency average output sound pressure level 90 dB input (HFA-OSPL90)

Answer 19

-Measuring the average output of the frequencies of 1000 Hz, 1600 Hz, and 2500 Hz with a 90 dB stimulus

Question 20

Response curve full-on gain with 50 dB inputs (FOG)

Answer 20

Measuring the output of the hearing aid when hearing aid gain is set to maximum, with a softer input (using a 50 dB stimulus)

Question 21

High frequency average full-on gain (HFA-FOG)

Answer 21

Measuring the average output with a 50 dB input of the frequencies of 1000 Hz, 1600 Hz, and 2500 Hz

Question 22

Reference test gain (RTG)

Answer 22

-Measuring the response of the HA at an appropriate user setting with a softer input of 60 dB (near average speech)

Question 23

Total harmonic distortion (THD)

Answer 23

-Measuring if there’s good fidelity of the signal from input to output
-Distortion measured in percentages

Question 24

Equivalent input noise (EIN)

Answer 24

Measuring how much internal noise the hearing aid is creating itself

Question 25

Battery current drain

Answer 25

-Measuring if the drain of the battery is reasonable (in mA)
-Measured with 65 dB and 90 dB inputs