Universidad de La Laguna

EVALUATION OF THE BENEFITS EVALUATION OF THE BENEFITS OF FM SYSTEMS IN COCHLEAR OF FM SYSTEMS IN COCHLEAR IMPLANTS AND HEARING AID IMPLANTS AND HEARING AID

USERSUSERSBarajas , J.J. (3), Mora, R. (2), Fernández, R. (1), De Lucas, G. (1)

Zenker, F. (1)

(1) Clínica Barajas (2) Fundación Canaria Dr. Barajas para la Prevención e Investigación de la Sordera (3) Universidad de la Laguna

SANTA CRUZ DE TENERIFE - CANARY ISLANDS - SPAINSANTA CRUZ DE TENERIFE - CANARY ISLANDS - SPAIN

Gobierno de CanariasConsejería de Educación,

Cultura y Deportes

1 st Conference EHDI August 13-14 Johannesburg - South Africa

CLASSROOM ACOUSTICSCLASSROOM ACOUSTICS– Background Noise (BN).– Reverberation Time (RT).– Speech Audibility Index (SAI).

FREQUENCY MODULATED SYSTEMSFREQUENCY MODULATED SYSTEMS – Selection of Candidates– FM Fitting and Verification

CANARIAS FM PROJECTCANARIAS FM PROJECTGobierno de CanariasConsejería de Educación,

Cultura y Deportes

AVERAGE CLASSROOM AVERAGE CLASSROOM (N=24)(N=24)

WIDTH: 6,31 mLENGTH: 9,78 mHEIGHT: 3,03 m

MEAN REVERBERATION TIME MEAN REVERBERATION TIME (N=24)(N=24)

UNE en ISO 3382 (2001) “Acoustic measurements of the reverberation time of rooms with referent to other. Acoustical parameters” (1997)

MEAN BACKGROUND NOISEMEAN BACKGROUND NOISE (N=24) (N=24)

Noise Rating Curves (NRC) - ISO

NOISE RATING CURVES (NRC)

CLASSROOMS ACOUSTIC CLASSROOMS ACOUSTIC N=24N=24SPEECH AUDIBILITY INDEX (SAI): SPEECH AUDIBILITY INDEX (SAI):

52%52%PSR = 90 %

% P

redi

cted

Spe

ech

Rec

ogni

tion

(PS

R)

% Speech Audibility Index (SAI)

Norm

al H

earin

g

Hearing I

mpaired

PSR = 48 %

FM SYSTEMFM SYSTEM TRANSMITTER RECEIVER

SUBJECTS(n = 23)

RANGE OF AGE: 5 – 14 YEARS

UNILATERAL COCHLEAR IMPLANT

(n = 7)

HEARING AID

(n = 9)

BILATERAL

(n = 7)

UNILATERAL

(n = 2)

n=16

Speech Discrimination TestSpeech Discrimination Test

LEXICAL FREQUENCY LEXICAL FREQUENCY

(% of correct phonemes recognition)

High Frequency WordsExamples:

Vaca- casapeluche- cepillo

Low Frequency WordsExamples:

Bufón- bizón, flácida- tímpano

PROCEDUREPROCEDURESpeech Discrimination TestSpeech Discrimination Test

☺☺NOISENOISE

☺☺QUIETQUIET

WITH FMWITH FMWITHOUT WITHOUT FMFM

TEST CONDITIONTEST CONDITION

FREQUENTLY WORDSFREQUENTLY WORDSWITH FM AND BACKGROUND NOISE WITH FM AND BACKGROUND NOISE

CLASSROOM CLASSROOM ACOUSTICACOUSTIC

BNICRA = 65 dBA

RT60 = 1,28 mseg

SNR = 7 dB

SAI = 52%

HEARING HEARING CORRECTIONCORRECTION

FM = Phonak Campus + Micro Link

HA= Phonak Supero 412

☺

INFREQUENTLY WORDSINFREQUENTLY WORDSWITHOUT FM AND BACKGROUND NOISEWITHOUT FM AND BACKGROUND NOISE

CLASSROOM CLASSROOM ACOUSTICACOUSTIC

BNICRA = 65 dBA

RT60 = 1,28 mseg

SNR = 7 dB

SAI = 52%

HEARING HEARING CORRECTIONCORRECTION

FM = Phonak Campus + Micro Link

HA= Phonak Supero 412

☺

RESULTSRESULTS

BOX PLOT OF % PHONEMES RECOGNITIONBOX PLOT OF % PHONEMES RECOGNITION

MAIN EFFECTSMAIN EFFECTS

HEARING CORRECTION FM

LEXICAL FREQUENCY BACKGROUND NOISE

MAIN EFFECTSMAIN EFFECTS

INTERACTIONSINTERACTIONSFM X LEXICAL FREQUENCYFM X BACKGROUND NOISE

FM BENEFITFM BENEFIT Dot Diagram

WITH FM

WITHOUT FM

% S

CO

RE

PHO

NEM

ES R

ECO

GN

ITIO

N> 85 % > 85 %

Sens: 62,5Sens: 62,5

Spec: 60,3Spec: 60,3

FM BENEFIT: WORDSFM BENEFIT: WORDSReceiving Operation Curves (ROC)

CONCLUSIONSCONCLUSIONS

The lexical infrequent words in noise conditions subtest may be use as a selection criteria for establish FM candidates