Verification: Real Ear Measurements

Question 1

What is some probe mic measurement terminology?

Answer 1

REUR/G
REOR/G
REAR/G
REIG
RESR
RECD
REDD

Question 2

What does RE stand for in the acronyms?

Answer 2

Real ear

Question 3

What does the 3rd letter represent in the acronyms?

Answer 3

U = unaided
O = occluded
A = aided

Question 4

What does G or R mean in the acronym?

Answer 4

G = gain (difference between the output intensity and the input intensity)
R = response (absolute measure of the SPL output arriving at the tympanic membrane)

Question 5

What type of responses fall under response?

Answer 5

Expect a high SPL value >90 dB SPL for acronyms ending in ‘R’

Question 6

What type of responses should you expect for gain?

Answer 6

Low SPL value

Question 7

Is the measurement the same no matter if its G or R?

Answer 7

Yes, just the way we are looking at the data is different

Question 8

What is the real ear unaided response (REUR)?

Answer 8

The measurement of the absolute SPL level of an open ear canal resonance, across all frequencies, at the tympanic membrane (input+ gain+ resonance= output)
Measures the natural amplification created by the shape of the pinna & open ear canal

Question 9

What is real ear unaided gain (REUG)?

Answer 9

The measurement of gain increase resulting from pinna, ear canal, and head diffraction effects, as measured in an open ear canal
Degree of change
REUR - input level = REUG

Question 10

Why do we measure REUR?

Answer 10

Knowing an individual’s ear canal resonance improve accuracy of prescriptive fitting (we need to know how much additional gain to add)

Question 11

What changes REUR?

Answer 11

Size, texture, shape, or presence of abnormal anatomy
Age: Pediatric, adult, elderly
One person can have 2 different REUR’s (different amplification needs)

Question 12

What is real ear occluded response or real ear occluded gain?

Answer 12

A measurement of insertion loss caused by placing an earmold/dome in the ear canal

Question 13

What is REOR?

Answer 13

A measurement of the attenuation of an input signal, across all frequencies, when a hearing aid is inserted and turned off
How did the insertion loss effect the response that arrived to the TM

Question 14

What is REOG?

Answer 14

A measurement of the gain reduction, across frequencies, when the hearing aid is inserted and turned off

Question 15

Do you have insertion loss with a open dome?

Answer 15

No

Question 16

Is there insertion loss with the tulip dome?

Answer 16

Yes, some
Some occlusion

Question 17

Is there insertion loss with a power dome?

Answer 17

Yes
Most occlusion, most insertion loss

Question 18

Can a power dome hold low frequency energy in the ear canal?

Answer 18

No, it escapes

Question 19

What causes maximum insertion loss?

Answer 19

Custom mold with no vent

Question 20

Does insertion loss lessen with a larger vent?

Answer 20

Yes

Question 21

Why do we test REOR?

Answer 21

Lets us see if the vent effect is releasing low frequencies as expected
Let’s us see if an open dome truly “open” (acoustically transparent”)?
Let’s us see if closed or power domes supply needed LF gain

Question 22

Does REOR identify which low frequencies are released due to the vent effect?

Answer 22

Yes
Adding gain where there is a vent effect is useless
The sound will just come out of the ear canal

Question 23

Does the REOR show if the vent introduced undesired standing wave effects that would impact amplification characteristics?

Answer 23

Yes