2017 Sec 1 Green Book

D. R. FRIEDMANN ET AL.

Speech perception both pre- and postoperatively was measured in quiet using consonant–nucleus–consonant (CNC) words as well as AzBio sentences and administered at 60 dB A. Hearing in Noise Hearing in background noise with various signal-to-noise ratios (SNR) was also tested with speech from the front and noise incident from the front, the better hearing ear, and the CI ear. Bamford–Kowal–Bench sentence-in-noise (BKB-SIN) (Etymotic Research 2005, Elk Glove Village, IL, U.S.A.) testing was administered for four adult subjects, whereas adap- tive hearing in noise test (HINT) testing was administered for the remaining six adult subjects. BKB-SIN is designed to assess sentence recognition in noise and consists of 36 lists of sentences presented in 4-talker babble noise. The sentences are presented at 65-dB SPL and the level of the noise is varied in 3 dB steps at fixed SNR beginning at þ 21 dB SNR (easy) descending to 6 dB SNR (hard) to obtain a speech reception threshold where the subjects can repeat key words 50% of the time (SNR-50); therefore, a lower score is indicative of better performance. The test was performed in the sound field in each ear individually and in the sound field in three conditions: speech front/noise front, speech front/noise right, speech front/noise left (n ¼ 4) or using Direct Connect (n ¼ 6) as noted above. Scores are indicated as dB SNR. In those patients tested in both sound field and using Direct Connect, results were found to be equivalent. As DC was integrated into our evaluations, we began using adaptive HINT testing in place of BKB-SIN for evaluating hearing in noise sentences on all new patients as well as for subsequent evaluations of previously implanted patients. Localization Localization testing was performed with the Direct Connect system as described above for five adult patients. A broadband noise from 1 of 12 virtual locations in the rear hemifield with locations numbered 1 through 12 on a response sheet, from right

to left, and positioned to represent an arc from 97.5 degrees (on the right) to 262.5 degrees (on the left) with 15 degrees separations between source locations. The task involves a verbal response corresponding to the perceived location of the sound. Localization testing is reported as the degrees root mean squared (RMS) error.

RESULTS

Adult Subjects, n U 12 Postoperative data were available for 10 adult patients (Table 3) as one transitioned care to another center whereas another was not a native English speaker. Data from most recent postoperative evaluation (3.4 yr 1.8) were used for performance comparison relative to pre- operative data. Table 4 demonstrates individual subject outcomes data. Speech Perception There was significant improvement in CNC word scores in the implanted ear with an average benefit of 54% (SE 8.4), p ¼ 0.001 in seven adult patients who underwent this test. Improvement in sentence scores on AzBio in quiet relative to the SSD ear was on average 82.5% (SE 14.5); however, this was not statistically significant ( p ¼ 0.11) as there were only two matched pairs. Sound field and direct connect results were equiv- alent in all patients. Hearing in Noise Speech-in-noise using binaural hearing BKB-SIN or adaptive HINT tests demonstrated that when noise was presented to the SSD/CI ear (speech front), the signal-to- noise ratio significantly decreased with an average reduction of 2.0 dB SNR (SE 0.8), p ¼ 0.047 in nine

TABLE 3.

Outcomes across clinical time points

1 year Postop (SD)

Most recent Postop

Preop vs Most Recent Postop p Value

Category

n

Preop (SD)

n

n

CNC words (% score) CI ear

9 4

2.9 (5.6) 98.0 (2.3)

8 8

55.4 (16.9) 98.0 (1.4)

7 7

57.7 (21.1) 95.7 (4.1)

0.001 0.594

Bilateral

AZ BIO (quiet) CI ear

5 5

6.6 (9.2)

3 3

95.0 (4.6)

2 2

92.0 (7.1)

0.111

—

Bilateral

100 (0)

100.0 (0)

100.0 (0)

HINT/BKB-SIN-noise front (SNR) Bilateral HINT/BKB-SIN-noise CI ear (SNR) Bilateral HINT/BKB-SIN-noise better ear (SNR) Bilateral

10

1.8 (1.9)

8

2.4 (1.0)

7

2.1 (1.3)

0.960

10

2.4 (2.7)

8

6.6 (2.5)

7

5.3 (3.0)

0.047

10

0.3 (3.1)

8

2.5 (2.0)

7

3.7 (1.5)

0.005

Localization (degrees RMS) CI ear

—

—

0 4

5 5

54.0 (11.6) 47.2 (9.4)

5 5

67.0 (15.1) 45.0 (16.6)

Bilateral

42.5 (7.7)

0.205

Speech perception of adult SSD patients who underwent cochlear implantation. p values calculated using dependent T test. ‘‘ — ’’ indicates measurement could not be calculated secondary to lack of matched pairs or the standard error of the difference being zero. As given in Table 1, the average time from surgery to the most recent post-op visit ( > 1 yr post-op) is 3.4 years (SD 1.8). AzBio (quiet) indicates Arizona biomedical sentences in quiet condition; BKB-SIN, Bamford–Kowal–bench sentence-in- noise test; CI, cochlear implant; CNC words, consonant–vowel nucleus–consonant words; HINT, hearing in noise test; RMS, root mean square; SNR, signal-to-noise ratio.

Otology & Neurotology, Vol. 37, No. 2, 2016

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