Transcript The benefit of using the Microlink MLx and MLxS FM radio aid systems, over distance and in noise, with the Nucleus ESPrit 3G.

The benefit of using the Microlink
MLx and MLxS FM radio aid
systems, over distance and in noise,
with the Nucleus ESPrit 3G speech
processor
Sarah Flynn and Elizabeth Wood
South of England Cochlear Implant Centre
University of Southampton
Paula Greenham Cochlear Europe Ltd
Acknowledgements
Mark Lutman
South of England Cochlear Implant Centre
University of Southampton
Cochlear Europe Ltd
Phonak UK
How FM radio aids help
the Signal to Noise ratio
Reduce speaker to ear distance
Desired sound predominates over
background noise
Research rationale
• Older children and adults for sound quality rating
• Word discrimination testing with McCormick
Automated Toy Discrimination Test (ATT)
• Tested in pink noise with noise behind subject to
simulate classroom conditions
• Tested at 10 metres from the radio aid transmitter
to simulate distance from speaker
• Trials with different microphone options
• Trials with different gains for MLxS / Campus S
• No change to processor sensitivity setting
Phonak Microlink MLxS
Microphone options
Handy mic with MLx
In noise
Omni setting same or better
than zoom (0 and 4dB
difference) or superzoom
(0 and 5dB difference)
Over distance
Omni slightly better than
zoom (2 and 3dB difference)
and better than superzoom
(10 and 7dB difference)
Campus S with MLx
In noise
Omni microphone
setting better than
directional (3.3 and 2.5
dB difference)
Over distance
Omni microphone
setting better than
directional (5 and 9dB
difference)
ATT scores at 10 metres
with different MLxS gains
dB(A) level for 71% correct
65
60
55
55
50
50
45
41
40
35
35
31
30
25
20
no FM 3 m
MLxS10
MLxS16
MLxS20
MLx
1
2
3
4
5
6
7
8
mean
Signal to noise ratio benefit
for different MLxS gains
25
S:N ratio benefit
20
15
10.2
8.3
10
8.3
4.9
5
0
MLxS10
-5
MLxS16
MLxS20
MLx
1
2
3
4
5
6
7
8
mean
MLxS with the 3G
• Mean results showed that MLxS receivers with
gains of 10, 16 and 20 gave a significant
improvement in noise (all p<0.03)
• At 10 metres, a gain of 16 was significantly
better than 10 (p<0.01), but 20 gave marginal
benefit over 16 (p=0.05)
• 4/8 subjects said the 10 gain MLxS was too
quiet to listen to for a long time
• 3/7 subjects said the 20 gain MLxS was too
loud to listen to for a long time
• The best sound quality rating was for 10 gain
(87%) and the worst was for 20 gain (67%)
Conclusions
• Microlink MLx and MLxS radio aids can be used
with cochlear implants
• MicroLink MLx
– significantly lower speech discrimination scores at 10m
than MLxS (p<0.001)
– not significantly different than MLxS in noise (p>0.07)
• Microlink MLxS –
– Gain of between 10 and 16dB appropriate for most users
but one level is unlikely to suit all users
– Probable saturation at >16
• Need for patient feedback and good communication
between clinic and education professionals
References
McCormick B (1977)The Toy Discrimination Test: an aid for
screening the hearing of children above the mental age of
2 years. Public Health London 91, 67-69
Ousey J, Sheppard S, Twomey T and Palmer A (1989) The
IHR /McCormick Toy Discrimination Test - description and
initial evaluation. British Journal of Audiology 23, 245-251
Wood E, Flynn S, Eyles J and Greenham P (2003) The benefit
of using an FM radio aid over distance and in noise, with
the Nucleus Esprit 3G speech processor. Poster at 9th
Symposium on Cochlear Implants, Washington DC.
Wood E, Flynn S and Greenham P (2003) The benefit of using
an FM radio aid over distance and in noise, with the
Nucleus Esprit 3G speech processor. Poster at ACCESS
Conference, Chicago.