1. BENEFIT OF BINAURAL HEARING WITH COCHLEAR IMPLANT AND HEARING AID Osaka Prefecture (840 million population) Takeshi Kubo, M.D. Department of Otolaryngology Osaka University School of Medicine

2. Chronological changes of CI cases and CI centers in Japan (120 million population)

3. Bilateral Cochlear Implantation on the same day

4. 1) Sound direction identification 2) Speech perception in quiet 3) Speech perception in noise a) Noise from front a) Noise from front b) Noise from right and left b) Noise from right and left Binaural hearing with CI/HA or CI/CI

5. Mechanism of sound source detection Inter-aural time difference (ITD) Inter-aural time difference (ITD) Inter-aural level difference (ILD) Inter-aural level difference (ILD) Normally hearing subjects ITD; 10 μsec ITD; 10 μsec ILD; 0.5 -1 dB ILD; 0.5 -1 dB can detect the difference in 2º Sound direction identification with bilateral ears Bilateral cochlear implant subjects ITD; 400 μsec-1msec ITD; 400 μsec-1msec ILD; 1 dB ILD; 1 dB can detect the difference in 10-25º.

6. Sound direction identification in bimodal (CI/HA) hearing mode

7. ③ 1.3m 1.3m ① ② ④ ⑤ Audiometer SCB-40 Methods Stimulation: 5 speakers at 45º separation 5 speakers at 45º separation white noise with 65dB SPL for 1 sec white noise with 65dB SPL for 1 sec 20 times from each speakers at random sequence 20 times from each speakers at random sequenceStimulation: 5 speakers at 45º separation 5 speakers at 45º separation white noise with 65dB SPL for 1 sec white noise with 65dB SPL for 1 sec 20 times from each speakers at random sequence 20 times from each speakers at random sequence Judgment: correct 2 correct 2 near-miss1 near-miss1 error0 error0Judgment: correct 2 correct 2 near-miss1 near-miss1 error0 error0

8. Subjects: Two HA users whose hearing levels were symmetric. Two HA users whose hearing levels were symmetric. T.S.T.S.T.S.T.S. M.K.M.K.M.K.M.K.○ ○ ○ ○ ○ ○ ○ × ×× × × × × × × × × ○ ○○ ○ 0dB 50dB 100dB ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ × ×× × × × × × × × × ○ ○ ○○ ○ ○○ ○ ○ ○ ○ × × × × × × × × × × × ○ ×× × × × × ×× × × × ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Result of bilateral HA users Only 5 errors to the adjacent speakers out of 100 trials Speakers: trials (scores) L （ - 90° ） F （ 0° ） R （ 90° ） RA （ 45° ） LA （ - 45° ） 19/20 （ 39/40 ） 20/20 （ 40/40 ） 18/20 （ 38/40 ） 19/20 （ 39/40 ） 95/100 （ 195/200 ）

9. Threshold Time for use CaseAge Gender Cause Deafness Duration deafness CI HAC IH A 1 2 48MUnknown3 y111.3118.81y4y 3 59FUnknown １ ｙ１ ｙ１ ｙ１ ｙ S.O.101.32y10m20y 4 65FUnknown ４ ｙ４ ｙ 106.392.51y6m8y 5 71 M Unknown １ ｙ１ ｙ 101.396.33y4y 6 80 F Unknown １ ｙ１ ｙ 108.8107.51y10m27 ｙ 84M Labyrinthitis １ ｙ１ ｙ 98.8112.53y4m8y Threshold Time for use CaseAge Gender Cause Deafness Duration deafness Rt LtRtLt 1 2 62MUnknown5 y111.3118.86 y3 y 32FUnknown 17 y S.O.110.33 y Subject CI/HA CI/CI

10. CI/HA: trials (scores) L （ - 90° ） F （ 0° ） R （ 90° ） RA （ 45° ） LA （ - 45° ） 11/20 （ 28/40 ） 11/20 （ 30/40 ） 10/20 （ 29/40 ） 6/20 （ 23/40 ） 6/20 （ 23/40 ） 9/20 （ 26/40 ） 9/20 （ 26/40 ） 46/100 （ 135/200 ） CI alone: trials (scores) L （ - 90° ） F （ 0° ） R （ 90° ） RA （ 45° ） LA （ - 45° ） 7/20 （ 19/40 ） 9/20 （ 29/40 ） 9/20 （ 29/40 ） 8/20 （ 240/40 ） 8/20 （ 240/40 ） 7/20 （ 24/40 ） 7/20 （ 24/40 ） 5/20 （ 209/40 ） 5/20 （ 209/40 ） 36/100 （ 115/200 ） K.K.L-CI/R-HA HA CI/HA CI Sound direction identification in binaural (CI/HA ) subjects HA: trials (scores) L （ - 90° ） F （ 0° ） R （ 90° ） RA （ 45° ） LA （ - 45° ） 4/20 （ 15/40 ） 4/20 （ 15/40 ） 4/20 （ 16/40 ） 4/20 （ 16/40 ） 7/20 （ 23/40 ） 7/20 （ 23/40 ） 5/20 （ 19/40 ） 5/20 （ 19/40 ） 4/20 （ 12/40 ） 4/20 （ 12/40 ） 25/100 （ 85/200 ）

11. Comparison of sound direction identification scores in CI, CI-HA, HA conditions 100 0 50 50 HA CI+HACI P=0.001 ＊ P=0.0197 ＊ ＊ ＊ CI/HA group Binaural hearing with CI and HA showed significantly better score than monaural hearing (CI or HA alone) condition.

12. Comparison of sound direction identification scores in CI alone and bilateral CI conditions Bilateral CI subjects showed better score than monaural listening with poorer CI, but showed similar performance when listening with the better CI.

13. Summary for sound direction identification study Binaural hearing with CI/HA had advantages for sound direction identification. Benefits: Aware for the direction of alarm sign. Can identify the speaker Can identify the speaker while talking with many people.

14. 1) Sound source detection 2) Better speech perception especially in noisy circumstances 1) Sound source detection 2) Better speech perception especially in noisy circumstances Advantages of binaural hearing Mechanisms of better hearing with two ears Summation effect Summation effect Binaural unmasking effect Binaural unmasking effect (binaural squelch effect) Head shadow effect (advantage) Head shadow effect (advantage) Mechanisms of better hearing with two ears Summation effect Summation effect Binaural unmasking effect Binaural unmasking effect (binaural squelch effect) Head shadow effect (advantage) Head shadow effect (advantage) CI N S CI HA

15. 2) Speech perception in quiet - summation effect – - summation effect – Speech perception score (%) Speech perception score (%) Speech reception threshold (SRT in dB) Speech reception threshold (SRT in dB) Binaural hearing with CI/HA or CI/CI

16. Binmodal (CI/HA) hearing under quiet condition Binmodal (CI/HA) hearing under quiet condition

17. * * * * ** 0 10 20 30 40 50 60 70 80 90 100 * * * * * * * * * * 40 5060708085905565753545 (dB) * Comparison of speech perception sores in three conditions (HA, CI, CI/HA) * * * 0 10 20 30 40 50 60 70 80 90 100 * * * 405060708085 90 5565753545 (dB) * * * * * HA CI/HA CI

18. Correct % for mono-syllabic words in binaural and monaural conditions (%) (CI/HA, CI-, HA-alone) (%) (CI/CI, CI alone)

19. Two parameters for speech perception tests Speech reception threshold (dB) Speech reception score (%)

20. Speech reception threshold (SRT) for HINT sentences under quiet condition Six bimodal (CI/HA) subjects dB(A) * Two bilateral CI subjects dB(A)

21. Both speech perception score (%) and reception threshold (SRT) were better in listening with two ears than listening with CI alone condition. Summary for speech perception in quiet - Summation effect - Sound from front CIHAS If SRT is better in 2dB, it corresponds to 10 15% better speech perception.

22. 3) Speech perception in noise a) Noise from front a) Noise from front - examination for bilateral unmasking (squelch) effect - Binaural hearing with CI/HA or CI/CI

23. Binaural hearing (CI/HA) under noisy circumstance

24. Sound and Noise from front CIHANS Speech perception scores (%) under the noise from front 100 ** CI/HA Noise 0 20 40 60 80 CI Quiet CI Noise CI/HA Quiet % Binaural unmasking (squelch) effect Speech Sound: 65dBSPL Multi-talker noise: 60dBSPL

25. Hearing in noise test (HINT) in binaural hearing subjects Sound and Noise from front CIHANS ● ● ● ● ● ●● ● ○ ● ● ●● ○ ○ ○ ○ ● ○ ○○ ○ ○ ○ 1 1 1 13 2 486 579 10 11 12 13 16 18 17 15 1420 19 1 Intensity of noise (dB) (dB) Speech Sound: 65dB Speech Sound: 65dB Multi-talker noise with variable intensities at 2 dB steps. Multi-talker noise with variable intensities at 2 dB steps.

26. HINT under the noise and speech from the front Binaural performance was better or as good as performance with the better ear alone under the condition with the speech and noise from front: binaural unmasking (squelch) effect !! S/N ratio (dB) P=0.04 *

27. 3) Speech perception in noise b) Noise from different directions b) Noise from different directions - examination for head shadow effect - - examination for head shadow effect - Binaural hearing with CI/HA or CI/CI

28. S/N (dB) Noise from Lt N CI CI S S/N (dB) Noise from Rt CI CI N S “ Head shadow advantage” Monaural hearing under the noise from right or left

29. ** S/N (dB) Binaural hearing (CI/HA) under the noise from three directions For noise on the left or right side, binaural performance can utilize “Head shadow advantage”. CI HA S N N N

30. N S CI CI N N Binaural hearing (CI/CI) under the noise from three directions S/N (dB)

31. Conclusion -2- For the binaural hearing under the noise condition “the head shadow advantage” was large, while “binaural unmasking effect” contributed little. Karaoke bar in Osaka

32. END OF PRESENTATION

33. P=0.04 A. S and N from front S N B.Noise from CI side CI HA N S C.Noise from HA side N HA CI S

34. ** S/N (dB) Head shadow advantage Head shadow advantage Comparison of SRT scores under the noise from three directions in binaural (CI/HA) hearing subjects  For noise on the left or right side, binaural performance was better or as good as performance with the contralateral ear. Noise from HA side HA CI NS

35. Sound from front Noise from Right Noise from Right Sound from front Noise from Left   Loudness summation ?   Head shadow effect ?   Binaural unmasking (squelch) effect ? Speech and noise from different directions S N S N

36. Noise from CI side CI HA N S Noise from HA side N HA CI S Head shadow effect Head shadow effect Binaural squelch Binaural squelch

37. Head shadow effect Head shadow effect Advantage of binaural hearing when the noise come from the better CI side. Noise from Rt. side Rt-CI Lt-CI N S S/N (dB)

38.  Binaural squelch Examination for binaural hearing : the noise comes from the poorer CI side Noise from Lt. side N CI CI S S/N (dB)

39. Sound direction identification in bimodal subjects 100 0 50 50 HA CI+HACI P=0.001 ＊ P=0.0197 ＊ ＊ ＊ I.M.L-HA/R-CI K.K.L-CI/R-HA HA CI/HA CI

40. S.M. COMBI 40+ M.T. Esprit 22 ＋ Esprit 24 Esprit 22 ＋ Esprit 24 Sound direction identification in Binaural subjects L-CICI/CI R-CI

41. 100 50 T.K. K.K.T.S.Y.F. I.M. Total チャンスレベル HA 単独装用、 CI 単独装用、 * ** *** <0.05, <0.01, <0.001 バイモーダル装用時 Error bar ： Srandard deviation 【バイモーダル装用】 T. K. （左 CI ） I. M. （右 CI ） Y. F. （左 CI ） T. S. （左 CI ） K. K. （左 CI ） 左（ - 90° ） 前（ 0° ） 右（ 90° ） 右前（ 45° ） 左前（ - 45° ） 6 /20 （ 25 ） 6 /20 （ 25 ） 3 /20 （ 23 ） 3 /20 （ 23 ） 5 /20 （ 22 ） 5 /20 （ 22 ） 10/20 （ 29 ） 11/20 （ 30 ） 12/20 （ 31 ） 11/20 （ 29 ） 6 /20 （ 20 ） 6 /20 （ 20 ） 8 /20 （ 23 ） 8 /20 （ 23 ） 7 /20 （ 26 ） 7 /20 （ 26 ） 3 /20 （ 17 ） 3 /20 （ 17 ） 5 /20 （ 21 ） 5 /20 （ 21 ） 11.4/20 （ 30.0 ） 9.8/20 （ 28.8 ） 5.6/20 （ 23.0 ） 8.8/20 （ 25.6 ） 46.2/100 （ 135.6 ） 13/20 （ 33 ） 9 /20 （ 29 ） 9 /20 （ 29 ） 18/20 （ 38 ） 13/20 （ 32 ） 14/20 （ 34 ） 7 /20 （ 26 ） 7 /20 （ 24 ） 8 /20 （ 22 ） 10/20 （ 27 ） 7 /20 （ 26 ） 8 /20 （ 24 ） 15/20 （ 32 ） 15/20 （ 35 ） 10.6/20 （ 28.2 ） 10.2/20 （ 24 ） 10.6/20 （ 29.2 ） 9.8/20 （ 28.8 ） 6.4/20 （ 23.8 ） 9.2/20 （ 26.6 ） * * * * * * * * * * * * * * * * * * * * * * * * 44/100 （ 137 ） 44/100 （ 137 ） 48/100 （ 140 ） 48/100 （ 140 ） 43/100 （ 121 ） 29/100 （ 114 ） 67/100 （ 166 ）

43. 結果（症例２・３） 補聴器単独装用、 人工内耳単独装用、 人工内耳と補聴器の両耳装用時 （ 補聴器とバイモーダル装用の検定は省略 ） * ** *** <0.05, <0.01, <0.001 症例 ２ 0 10 20 30 40 50 60 70 80 90 100 405060708085 90 55657545 (dB) S/N （ dB ） 静寂下 正面 右 (CI 側 ) 左 (HA 側 ) 雑音負荷 0 10 20 30 40 50 60 70 80 12 0 8 4 10 6 2 * * * * 症例 ２ 67-S 語 表 (dB) Japanese HINT 症例 ３ 0 10 20 30 40 50 60 70 80 90 100 405060708085905565753545 (dB) * * * * * * * * * * * * * * * * * S/N （ｄ B ） 10 20 30 40 50 60 70 80 0 静寂下 正面右 (HA 側 ) 左 (CI 側 ) 雑音負荷 16 12 8 4 0 20 * * * * * * * * * * * * 67-S 語 表 Japanese HINT 症例 ３

44. Threshold Time for use CaseAge Gender Cause Deafness Duration deafness Rt LtRtLt 1 2 62MUnknown5 y111.3118.86 y3 y 32FUnknown 17 y S.O.110.33 y Subject Pre-op. threshold CI side Case 123456 AgeGender 84M71M59F80F65F48M Length CI use 2y10m2y6m2y3m1y4m1y6m Length HA use 8y 8y10m20y27y 3y 3y 1y3y4m15y5y4y4y Causedeafness labyrinthitisunknownunknownunknownunknownunknown Type CI CI N22N24N24N24N24N24112.5 96.25 96.25111.2 107.5 107.5 92.5 92.5118.7 98.7 98.7101.2 S.O. S.O.108.7106.2111.2 Threshold HA side HA side Durationdeafness

45. Summary (1) ？ ？

46. Comparison of sound direction identification between CI-HA and CI/CI groups 100 0 50 50 HA CI+HACI P=0.001 ＊ P=0.0197 ＊ ＊ ＊ CI/HA group 100 0 50 50 Lt CI Bil CI Rt CI ＊ n.s. CI/CI group P=0.024 ＊

47. Auditory and visual information processing in auditory cortical areas of cochlear implant users ． - PET activation study -

48. Ménière’s disease;

49. Speech perception score Speech perception score (%)