Real Ear Measurements

Question 1

The frequency Response of the patient’s ear canal including any amplifications produced by the HA is tested with the use of this

Answer 1

Real Ear Measurements

Question 2

In order to have accurate, repeatable REM’s, it is critical to have a good test environment. What should the ideal test room look like

Answer 2

• Large room as possible (Sound booth is ideal)
• Free of vertical and horizontal reflective surfaces such as chairs and desks and other office furniture
• Reflective surfaces should be at least twice as far away from pt as the sound field speaker
• Sound treated ceiling if possible
• Carpeted floor and curtains

Question 3

What position should the sound field speaker be during a REM

Answer 3

-pointed away from any nearby walls or corners

Question 4

How should the specialist performing the measurement be position

Answer 4

Should be where they can operate the real analyzer and yet out of the way of the path of the sound field speaker

Question 5

How should the pt be positioned during a REM

Answer 5

• Position pt 12-30” from sound field speaker
• either at 0 degrees (in front of pt) or 45 degrees (off to the side) is debatable so specialist should use their discretion.

Question 6

What should be done before REMS can be performed

Answer 6

The real ear analyzer microphones should be calibrated and the sound field leveled.

Question 7

REMS typically use two speakers what are they?

Answer 7

• a reference microphone speaker outside the ear and a probe microphone inside the ear canal

Question 8

What is positioned in the Pt’s ear to measure the signal exactly as the pt hears it

Answer 8

Probe tube which is connected to the probe microphone

Question 9

How should the probe tube be positioned inside the canal

Answer 9

As close to the ED as possible

The end of the probe tube should be within 5mm from the eardrum

Question 10

What are the two methods of probe insertion

Answer 10

Otoscopic Examination-
1.use otoscope to examine and estimate length to ED, still using otoscope carefully advance it until it reaches within 6mm of ED, then mark tube at intertragal notch.

Unaided measurement-
Set up REM including calibration and leveling and place pt in front of speaker ear hook on ear and probe ready for insertion, introduce continuous broadband and slowly insert probe

Question 11

What are the most commonly encountered real ear targets

Answer 11

• NAL-RP- Most common and verified RE target
• 1/2 Gain- Gain of HA should equal 1/2 of hearing loss
• Berger-one of the first comprehensive procedures
• POGO- Prescription of Gain Output- it is an insertion gain method similar to 1/2 gain rule
• POGO II- For severe Hearing losses
• Libby- 1/3 Gain, 2/3 Gain- Moderate Losses should be fit equal to 1.3 of loss and severe at 2/3 of the loss

Question 12

What does the Insertion Gain Method

Answer 12

Specialist measures Pt’s Real ear Unaided gain (REUG) then the Real ear aided gain (REAG) the analyzer calculates the differences between the two measurements to obtain the Real ear Insertion Gain (REIG)

REIG=REAG-REUG

Question 13

REIG

Answer 13

Real ear insertion Gain- The amount of gain that the HA is providing above and beyond the natural resonance of the ear.

Question 14

REUR

Answer 14

Real Ear Unaided Response- the measured frequency response in dB SPL with a probe tube microphone int he unaided, unoccluded ear canal- used to measure ear canal resonance

Question 15

REOR

Answer 15

Real Ear Occluded Response- Measures the frequency response in dB SPL with a probe microphone in the canal with the earmold in place and HA turned off- measures resonance breathed by interaction between earmold and canal volume

Question 16

REIR

Answer 16

Real Ear Insertion Response— The mathematical difference between the REAR and REUR when both are measured at the same point in the canal with the same sound field

REAR-REUR=REIR

Question 17

REAR

Answer 17

Real Ear Aided Response— Represents the in situ aided frequency response measured in dB SPL with a probe tube mic in the aided external Auditory Canal AKA the HA response as opposed to changes in the ear canal.

Question 18

What is not a coupler used for measuring HA performance

Answer 18

Zwisks Ear Simulator

Question 19

A real ear measurement system incorporates all of the following

Answer 19

Signal Generator, reference microphone, measurement microphone, display device

Question 20

REUR Measurements are taken in

Answer 20

An open human ear canal

Question 21

At what distance from the Tympanic Membrane should the end of the probe tube be placed

Answer 21

Within 5 mm

Question 22

When testing compression hearing aids, which signal type is best to use

Answer 22

Fast Fourier Transform

Question 23

Loud Speaker placement should be

Answer 23

1 meter at 45 degrees azimuth

Question 24

Which of the following is not included in correct test protocols

Answer 24

Plugging the HA vent to control feedback

Question 25

RESR measurements for compression HA’s have been replaced with

Answer 25

A family of curves starting at a soft level and gradually increasing in intensity

Question 26

Which of the follow real ear targets has been documented to be the best for Non Linear HA’s

Answer 26

None have been proven to be better than any other

Question 27

Insertion Loss occurs when

Answer 27

The level in the ear canal with a HA inserted is less than the input level