Real Ear Measurement (REM)
Why is REM important?
REM are the most reliable and efficient method for assessing the benefit provided by the hearing aid.
Real ear measures involve positioning a probe tube in the patient’s ear canal approximately 6mm from the patient’s eardrum. Then, after testing to make sure that the probe tube is appropriately positioned, the hearing aid is also placed in the patient’s ear and the verification process commences. real ear measurement
REUR (Real-Ear Unaided Response)
The SPL, across frequencies, measured in the open (unaided) ear canal for a given input signal.
REAR (Real-Ear Aided Response)
The SPL, across frequencies, measured in the open (unaided) ear canal for a given input signal.
REIG (Real-Ear Insertion Gain)
The amount of gain provided by the hearing instrument alone calculated by subtracting the REUG from the REAG across frequencies or by subtracting the REUR from the REAR across frequencies. Facebook Page
REOR (Real-Ear Occluded Response)
The SPL across frequencies, measured in the ear canal, with the hearing aid in place and turned off. An REAR with the hearing aid turned off.
RECD (Real-Ear-to-Coupler Difference)
Difference in dB across frequencies, between the SPL measured in the real-ear and in a 2cc coupler, produced by a transducer generating the same input signal.
Why should you do it? RECD
Arguably the most useful application of the RECD is in the prediction of real-ear output when measuring hearing instruments in the 2cc coupler. Given that the RECD allows us to know the difference between output in the real-ear and the 2cc coupler, real-ear hearing aid output (e.g., REAR, RESR) can be accurately predicted to within approximately 2 dB (Seewald et al, 1999).
The ability to predict hearing instrument output offers a number of advantages, which, as described by Seewald (1997) include the following:
1. The audiologist will know the levels of amplified sound delivered into the patient’s ear canal. real ear measurement
2. The unique acoustic properties of the ear and earmold coupling (if the RECD is conducted with the earmold) will be accounted for. This helps avoid errors that can occur when using average values in the fitting process. real ear measurement
3. All hearing instrument response shaping can be performed in the hearing aid test chamber, under highly controlled acoustic conditions.
4. The degree of cooperation and amount of time required from the patient in the fitting process is greatly reduced. real ear measurement