Universidad de La Laguna EVALUATION OF THE BENEFITS OF FM SYSTEMS IN COCHLEAR IMPLANTS AND HEARING AID USERS Barajas, 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 - SPAIN Gobierno de Canarias Consejería de Educación, Cultura y Deportes 1 st Conference EHDI August Johannesburg - South Africa

CLASSROOM ACOUSTICS – Background Noise (BN). – Reverberation Time (RT). – Speech Audibility Index (SAI). FREQUENCY MODULATED SYSTEMS – Selection of Candidates – FM Fitting and Verification CANARIAS FM PROJECT Gobierno de Canarias Consejería de Educación, Cultura y Deportes

AVERAGE CLASSROOM (N=24) WIDTH: 6,31 m LENGTH: 9,78 m HEIGHT: 3,03 m

MEAN REVERBERATION TIME (N=24) UNE en ISO 3382 (2001) “Acoustic measurements of the reverberation time of rooms with referent to other. Acoustical parameters” (1997)

MEAN BACKGROUND NOISE (N=24) Noise Rating Curves (NRC) - ISO NOISE RATING CURVES (NRC)

CLASSROOMS ACOUSTIC N=24 SPEECH AUDIBILITY INDEX (SAI): 52% PSR = 90 % % Predicted Speech Recognition (PSR) % Speech Audibility Index (SAI) Normal Hearing Hearing Impaired PSR = 48 %

FM SYSTEM TRANSMITTERRECEIVER

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 Test LEXICAL FREQUENCY (% of correct phonemes recognition) High Frequency Words Examples: Vaca- casa peluche- cepillo Low Frequency Words Examples: Bufón- bizón, flácida- tímpano

PROCEDURE Speech Discrimination Test ☺☺NOISE ☺☺QUIET WITH FM WITHOUT FM

TEST CONDITION

FREQUENTLY WORDS WITH FM AND BACKGROUND NOISE CLASSROOM ACOUSTIC BN ICRA = 65 dBA RT 60 = 1,28 m seg SNR = 7 dB SAI = 52% HEARING CORRECTION FM = Phonak Campus + Micro Link HA= Phonak Supero 412 ☺

INFREQUENTLY WORDS WITHOUT FM AND BACKGROUND NOISE CLASSROOM ACOUSTIC BN ICRA = 65 dBA RT 60 = 1,28 m seg SNR = 7 dB SAI = 52% HEARING CORRECTION FM = Phonak Campus + Micro Link HA= Phonak Supero 412 ☺

RESULTS

BOX PLOT OF % PHONEMES RECOGNITION

MAIN EFFECTS HEARING CORRECTION FM

LEXICAL FREQUENCY BACKGROUND NOISE MAIN EFFECTS

INTERACTIONS FM X LEXICAL FREQUENCY FM X BACKGROUND NOISE

FM BENEFIT Dot Diagram WITH FM WITHOUT FM % SCORE PHONEMES RECOGNITION > 85 % Sens: 62,5 Spec: 60,3

FM BENEFIT: WORDS Receiving Operation Curves (ROC)

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