REM protocols on Open fit

[snoo-pie]

Hi all,

I've been asked to help write a protocol for performing Real Ear Measurements on open fit hearing aids (specifically Oticon Corda) and wondered if anybody has any pointers or would be willing to share their department's protocol.

I have the article by Lantz et al. but that's about it.

I know about using the substitution method and a sweep instead of FFT but I need more to back this up as there is quite strong opposition against REMing Cordas within the department and really want to be able to stand my ground.

Any help would be very much appreciated.

[DaveO]

Hi

have you seen this website?:

http://www.danalogic.info/advanced_fitting.php

It's the recommended way to open-fit GN Resound Danalogic aids, but I'm sure it applies equally to all open-fit hearing aids

As you say, you need to use the Pure Tone Sweep. Also make sure to check the "Use Open-REM method for REUR 1-4" box in the REM module settings. Do your unoccluded response, don't do the occluded response, and then go on to Insertion Responses.

Hope it helps
DaveO

[JasonS]

Hi,

Really it also depends on what equipment you're using. REM'ing on a Unity System is completely different from an Auricle.

Unity 2 recommends that you use ICRA 6 and mute the aid during the initial calibration tone, then REM as normal (as you would with a mould)

Auricle is very different, with as you say using a pure tone sweep not FFT. I recently had a long chat to the Otometrics audiologist about why they are still using a pure tone signal to verify, who basically said that in the next few months Auricle REM's will be changing considerably to be more like that of Unity.

Jason

[WASIELEWSKI]

hello , you can read its various documents on the web if it's not already done.

http://www.interacoustics.com/eprise...alFittings.pdf

http://journals.lww.com/thehearingjo...me_tips.6.aspx

http://www.bernafon.com/ca_en/_downl...Tech_Topic.pdf

[shaikha]

Hi all,

I've been asked to help write a protocol for performing Real Ear Measurements on open fit hearing aids ...

I have the article by Lantz et al. but that's about it.

Any help would be very much appreciated.

Me too!

The Danalogic website is quite good.

I've started with an outline about the different methods.

What do you think about DFS? should you enable feedback cancellation before or after REMs? - does anyone have any evidence for this (Lantz et al touch on it but no results have been given)

[sue]

Hi
Articles have appeared in audiology on line over the last couple of years that might help and give you more references. I suggest:

http://www.audiologyonline.com/askex...uestion_id=539

and

http://www.audiologyonline.com/artic...rticle_id=2046

and
http://journals.lww.com/thehearingjo...me_tips.6.aspx

[shaikha]

Hi all,

there is quite strong opposition against REMing Cordas within the department and really want to be able to stand my ground.

Any help would be very much appreciated.

Personally I feel REMs should be done on allhearing aids whether open-fits or not.
REMing 'personalises' the hearing aid fitting...

[mancie]

Personally I feel REMs should be done on allhearing aids whether open-fits or not.
REMing 'personalises' the hearing aid fitting...

I totally agree with this post. REMs should be done where possible. I regularly REM open fit (oticon corda) using Unity 2. (using the procedure already mentioned here, mute during the signal calibration phase then use the ICRA signals).

I have found that corda fits are often very low on gain 20dB or worse, although in some cases they can be spot on without adjustment. In mild hearing loss fittings (or the lower end of moderate) this often means that the hearing aid isn't doing much at all. I think I've posted on this before. REMS for corda really should be mandatory.

[snoo-pie]

Personally I feel REMs should be done on allhearing aids whether open-fits or not.
REMing 'personalises' the hearing aid fitting...

I completely agree, which is why I want to have a solid protocol to encourage everybody to do them.

Thanks for all of the links and info, will have a fish through and see what is what!

[lol26]

I completely agree, which is why I want to have a solid protocol to encourage everybody to do them.

Thanks for all of the links and info, will have a fish through and see what is what!

Hi

Does anyone know the REM protocol for a life mould. This is basically a meatal plug with a corda tube - so a mix of mould and corda.

I feel the ear mould protocol to be correct as the mould is not open and the vent size can be added to the fitting software, however the diameter of the tube must have an effect.

Any thoughts?

[Gephaudio]

Hi

Does anyone know the REM protocol for a life mould. This is basically a meatal plug with a corda tube - so a mix of mould and corda.

I feel the ear mould protocol to be correct as the mould is not open and the vent size can be added to the fitting software, however the diameter of the tube must have an effect.

Any thoughts?

You are quite correct. The 'open' REM protcol is used so the the reference microphone of the REM device, does not pick up the amplified signal leaking from the ear canal. This would affect the output from the loudspeaker.
Using a cord/life mould blocks the ear canal so little, to no sound leaks out.

Hope this helps

Would agree with all the other posters that REMs should be done.
What should be moved up the agenda is an open fit target for NAL NL and DSL i/o as both rationals assume an ear mould being used

[Rajesh Ravi]

You are quite correct. The 'open' REM protcol is used so the the reference microphone of the REM device, does not pick up the amplified signal leaking from the ear canal. This would affect the output from the loudspeaker.
Using a cord/life mould blocks the ear canal so little, to no sound leaks out.

Hope this helps

Would agree with all the other posters that REMs should be done.
What should be moved up the agenda is an open fit target for NAL NL and DSL i/o as both rationals assume an ear mould being used

Hi,
this has been an interesting debate whether we can use the existing target for open fit or not, as you have mentioned, both NAL and DSL formulae assume the use of an ear mould.
Are there any updates regarding this? Anybody consider a seperate formula for open fit?!!!

[Gephaudio]

Now the technology has moved on. Anyone with advice how to REM reciever in the canal devices, no earmould no size 13 tubing either. Onlt option to use manufactures' targets. Big difference between the two obviously due to the change in parameters as mentioned above