2017 Sec 1 Green Book

SINGLE-SIDED DEAFNESS COCHLEAR IMPLANTATION

adult patients tested. When noise was presented to the better hearing ear (speech front), the signal-to-noise ratio significantly decreased with an average reduction of 4.6 dB (SE 1.0), p ¼ 0.005. Localization No significant difference in sound localization was found when comparing preoperative data to 1-year post- operative data with regards to root mean square (RMS) error values (n ¼ 4 matched pairs, p ¼ 0.61). Further- more, no difference was found when comparing preop- erative data to postoperative data from more than 1 year after surgery (n ¼ 2 matched pairs, p ¼ 0.21). Subjective Assessment All adult subjects were able to integrate the signal from the implanted ear (electrical) with the acoustic signal, without deterioration in speech understanding in their better hearing ear. All patients with tinnitus reported suppression since device activation. Pediatric Subjects (n U 4) Our institutional experience consists of four pediatric SSD patients implanted to date. The first child was implanted at the age of 10, and is now 14 years old. She has enlarged vestibular aqueduct (EVA) and a long duration of deafness in her left ear. Preoperatively, she obtained 0% on CNC words in the effected ear alone. Her score at the 1-year post-op interval was 18% but has since dropped to 6% by year three. Concurrently, there has been a progressive decline in the nonimplanted ear alone from 98 to 80% at her most recent evaluation. At 3 months and 1 year, BKB-SIN scores were significantly improved in all three conditions compared with preop- erative values, but have since declined to poorer than preimplant scores. Although she initially wore the device regularly, she now wears it only in school — though she does report subjective benefit during use as duly noted by her parents and teachers. Evidence from our experience with SSD patients after cochlear implantation is that although the quality of the auditory percept may not be acceptable, as they lose hearing in the nonimplanted hearing ear (as expected in patients of EVA, for example), they begin to better integrate and interpret the CI signal. This has not been the case to date with this patient as she has been wearing her device with less regularity over time. When questioned, she seems too focused over concern for her declining acoustic hearing to recognize the long-term benefit of using her implant more regularly. The second pediatric impatient was implanted at the age of six and had PBK-word scores of 20%, HINT-Q was 76% and HINT-N was 49% in implant only con- dition at 3-months poststimulation. Bimodal scores were 100% showing that the signal was not being degraded by the addition of an electrical stimulus to the normal hearing ear. Interestingly, despite the apparent increase in performance, he only wears the CI in school and sometimes complains that it ‘‘bothers’’ the good ear.

9 47 2.42 CPA lesion 7 73 16 54 2.0 1.0 0.5 1.3 1.0 0.3 — — AB 10 62 1.58 SSNHL 10 98 — 42 1.5 2.0 2.8 8.3 1.4 4.8 — 52 Nucleus

Bilateral Device

5 30 1 SSNHL 20 85 0 76 3.0 1.3 5.5 4.5 3.5 3.8 — — Nucleus

6 62 0.75 SSNHL 23 85 2 76 0.1 4.0 1.5 5.5 1.5 4.5 — — Nucleus

7 36 0.42 COM 10 112 0 66 1.5 3.0 6.0 6.3 3.5 0.8 — — Nucleus 8 56 3.42 SSNHL 17 90 0 84 0.5 1.6 0.5 1.5 0.8 4.5 — — Nucleus

4 27 1.08 SSNHL 0 100 0 49 1.9 2.9 0.4 8.3 5.5 4.3 31 45 Nucleus

2 64 21 Me´nie`re’s 18 83 0 24 6.5 3.3 3.5 8.6 0.3 3.1 48 44 Nucleus 3 65 1.75 SSNHL 5 78 8 63 0.5 1.9 5.5 7.8 2.3 1.0 45 35 Nucleus

1 58 0.92 SSNHL 17 95 0 69 0.6 4.0 1.4 7.4 4.8 3.1 46 60 Nucleus

1 Year

Postop,

Localization

(degrees RMS)

Preop,

Bilateral

1 Year

Postop,

Bilateral

HINT/ BKB-SIN, Noise Better Ear (SNR) Preop,

Bilateral

1 Year

Postop,

Bilateral

HINT/ BKB-SIN, Preop,

Noise CI Ear (SNR) Bilateral

One Year Postop,

Bilateral

HINT/BKB-SIN,

Noise Front (SNR) Preop, Bilateral

Individual adult subject outcomes data after SSD cochlear implantation. Pure-tone average (PTA) was calculated using air conduction lines at 0.5, 1, and 2 kHz. ‘‘ — ’’ indicates that data were unavailable. For subjects 6 and 8 in table (‘‘ID’’ column), data from 3 years post-op were used as 1 year post-op data were unavailable. AB indicates Advanced Bionics; COM, chronic otitis media; RMS, root mean square; SD, standard deviation; SNR, signal-to-noise ratio; SSNHL, sudden sensorineural hearing loss.

TABLE 4. Individual subject data CNC Words Score (% score) One Year Postop, CI Ear

Preop,

CI Ear

PTA of

SSD Ear

Normal Ear

PTA of

Deafness (yr) Etiology

Duration of

Age at

Implantation

ID

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