Verifying Hearing Instruments Using REM
by Chelsea McDonald H.I.D & Ryan Steckley H.I.S
As Hearing Instrument Specialist, it is our job to provide our clients with the best hearing possible, using best practices. These best practices include a proper audiometric assessment, hearing aid selection, counseling, fitting and dispensing of hearing instruments. Proper fitting and programming practicing have a big influence on whether or not the client wears the hearing aid or puts it away for safe keeping.
Generally a hearing aid is programmed according to the client’s audiogram through the manufacturers proprietary fitting formula, in other words, “best fit”. After programming the hearing aid and receiving feedback from the client on how their current surrounding environments sound to them, minor adjustments are made so the client feels comfortable and not too overwhelmed with the new sounds they perceive. This is a universal practice when fitting a hearing aid. Using the real-ear measurement verification fitting method versus the generic “best fit” method has resulted in a remarkable improvement of clarity of clients’ hearing.
Here is a simplified overview of how we use Real Ear Measurements (REM) to precisely fit hearing aids to the client’s prescription based on their hearing assessment.
In order to provide the client with the best-fit possible the ear canal must be clean from any wax or debris. After calibrating the REM testing equipment, we then take a measurement of the client’s ear canal by placing a microphone probe tube into the ear canal, just millimeters in front of the eardrum. The probe tube microphone then reads how sound is travelling to the eardrum. A hearing aid is not a one-size-fits-all device. Every ear has a specific size and length, much like a fingerprint. We then place the muted hearing instrument into the ear (while the probe tube is still inserted) and take another measurement of how much sound is blocked with the hearing aid in the ear. After adding all the acoustic parameters (style of hearing instrument, vent sizes, testing equipment used, etc.) into the fitting software, we then perform fine-tuning.
As the hearing instruments are on and the probe microphone is right in front of the eardrum, speech in various languages is then played from the loudspeaker that is placed directly in front of the client. We are able to take an objective measurement of exactly how the sound is amplified to the eardrum. This allows the clinician to fit the hearing aids accurately to the prescription using the clients’ actual ear canal volume, not the “best fit” formula that is based on the average statistics. As speech is played through the speaker, the clinician makes volume adjustments in a range of different frequencies on the hearing instrument software until the hearing aid meets the prescription. Depending on if the client is a new user or a long-term hearing aid user, we then establish a comfortable listening volume based on the adjustments made from the REM fitting, as sometimes the volume can be a bit overwhelming for first-time users. Our goal with using REM is to provide more audible sounds and most importantly, clarity of speech.
Often clinicians do not use REM as standard protocol in their practiced due to costs of the testing equipment, more time being required than the “best-fit” method, and lack of confidence when using the testing equipment. (Ross, 2012) REM testing only takes about 15-25 minutes, and according to the MarkTrek V Study, more clients are satisfied with their hearing aids after verification using REM (Kochkin, 2000).
Client-centered hearing clinics provide each and every client with the best possible fitting and follow-ups, making sure the clients are satisfied with their hearing aid purchase. Real Ear Measurement testing has made a large impact on client satisfaction. This method should be common practice for all hearing instrument fitting.
If you have any questions regarding Real Ear Measurements, feel free to call Nu-Life Hearing Centre at 905-697-3838