Sound therapy for cochlear implant users with tinnitus

Figures & data

Figure 1. Flowchart of the study. Phase 2 was optional and included a baseline period (without sound therapy) of at least 2 weeks with a maximum duration of 3 weeks, followed by a take-home evaluation (with sound therapy) of at least 5 weeks with a maximum duration of 6 weeks. CART: Cochlear™ Active Relief from Tinnitus.

Table 2. Background sound use in phase 2.

Subject	Most frequently used background sound	Average CI use per day (hours)		Average background sound use per day (hours)	Background sound use / CI use (%)	Preferred volume level*
U-02	‘Beach Surf’	15.6		3.1	20	4
U-04	‘Water Creek’	8.4		1.3	15	3
U-05	Electronic datalogs showed non-use of background sounds during intervention period
U-07	‘Water Creek’	15.2		9.7	64	9
U-08	‘Ocean’	11.2		7.6	68	6
U-12	‘Water Creek’	15.4		10.5	68	12
U-13	‘Calming Waves’	5.5		5.5	100	5
M-01	Electronic datalogs missing due to a technical issue
M-02	‘Breaking Waves’	14.9		12.0	81	11
M-03	‘Shoreline’	13.9		8.5	61	8
M-04	‘Breaking Waves’	14.8		4.0	27	5
M-06	‘Water Creek’	16.2		4.8	30	6
M-10	‘Water Creek’	17.0		12.8	75	5
M-15	‘Water Creek’	17.0^†		6.1	36	12
Median (range)		15.1 (5.5–17.0)		6.9 (1.3–12.8)	62 (15–100)	6 (3–12)

Note: Data on the subject's CI and background sound use were extracted from the electronic datalogs of the sound processor and remote control. *The volume of the background sound could be adjusted by the subject from 0 (minimal audible level) to 20 (maximum level), with a linear distribution of the electrical Dynamic Range. †Estimated from previous electronic datalogs, due to a technical issue.

Table 1. Subject demographics.

Subject	Sex	Age (years)	Tinnitus before CI	Implanted side	CI use (years)	Tinnitus side	Tinnitus at visit 1 (CI on)			Completed phase 2
							VAS-L	VAS-A	TFI
U-01	M	65	Yes	Left	1	I	3.7	3.8	18	No
U-02	M	67	Yes	Left	13	B	6.2	6.9	20	Yes
U-03	M	33	Yes	Left	14	B	7.3	5.5	52	No
U-04	F	44	Yes	Right	14	B	5.0	5.0	57	Yes
U-05	F	62	Yes	Right	21	B	9.1	9.1	59	Yes
U-06	M	56	Yes	Right	16	C	2.2	3.1	18	No
U-07	M	55	Yes	Right	16	C	5.7	2.6	23	Yes
U-08	F	59	Yes	Right	8	B	5.7	3.9	39	Yes
U-09	M	78	Yes	Left	1	I	6.1	6.0	61	No
U-10	F	58	Yes	Right	13	C	6.9	5.5	20	No
U-11	F	44	Yes	Left	1	B	6.5	5.5	56	No
U-12	F	50	Yes	Right	3	C	6.6	2.9	58	Yes
U-13	F	52	Yes	Right	15	B	7.7	5.1	17	Yes
U-14	M	40	Yes	Right	3	B	8.9	8.3	45	No
U-15	M	74	Yes	Left	13	B	8.6	3.7	8	No
U-16	F	70	Yes	Right	3	B	6.4	3.6	66	No
M-01	F	62	Yes	Left	6	I	4.9	5.3	24	Yes
M-02	M	66	No	Left	12	C	4.2	4.0	40	Yes
M-03	M	73	Yes	Left	2	B	7.8	6.3	54	Yes
M-04	F	69	Yes	Right	6	B	8.7	8.5	61	Yes
M-05	M	66	Yes	Left	11	B	7.5	7.8	14	No
M-06	M	71	Yes	Right	11	B	5.6	5.1	35	Yes
M-07	M	70	Yes	Right	2	I	1.0	0.8	12	No
M-08*	M	78	Yes	Left	14	I	0.0	0.0	8	No
M-09	M	70	Yes	Left	7	B	0.2	0.2	10	No
M-10	F	68	Yes	Right	8	B	8.0	7.0	42	Yes
M-11^†	F	62	Yes	Left	1	I	0.3	0.2	0	No
M-12^‡	M	74	No	Right	6	I	0.0	0.0	0	No
M-13	F	73	Yes	Left	6	B	5.9	5.7	46	No
M-14	M	72	Yes	Right	6	C	1.5	1.6	29	No
M-15	M	66	Yes	Right	5	B	5.5	4.8	40	Yes
M-16	M	32	No	Right	2	I	6.7	5.6	60	No
n/mean (SD)	19:13 (M:F)	62 (13)	29:3 (y:n)	14:18 (l:r)	8 (6)	18:6:8 (B:C:I)	5.3 (2.8)	4.5 (2.5)	34.2 (20.6)	14:18 (y:n)

Note: *Participant only experienced tinnitus in his car. †Participant reported that tinnitus only appeared sporadically and did not experience tinnitus for the last 3 weeks. ‡Participant did not experience tinnitus in the week before visit 1 due to reconfiguration of the CI. B: bilateral; C: contralateral; CI: cochlear implant; I: ipsilateral; M-: Maastricht University Medical Center+; U- = University Medical Center Utrecht; TFI: Tinnitus Functional Index; VAS-A: Visual Analogue Scale for tinnitus annoyance; VAS-L: Visual Analogue Scale for tinnitus loudness.

Figure 2. VAS on tinnitus annoyance and loudness. Baseline = individual scores averaged across 2 weeks without use of sound therapy; Intervention = individual scores averaged across five weeks with use of sound therapy. *p < 0.05, ^†Participant withdrew from the study and did not complete phase 2 (no data of baseline and/or intervention period), ^‡Calculated for the 14 participants that completed phase 2. VAS: Visual Analogue Scale.

Figure 3. Tinnitus Functional Index (TFI). Baseline = individual scores averaged across two weeks without use of sound therapy; Intervention = individual scores averaged across five weeks with use of sound therapy. ^†Participant withdrew from the study and did not complete phase 2 (no data of baseline and/or intervention period), ^‡Calculated for the 14 participants that completed phase 2.

Figure 4. Speech perception in quiet was tested at 65 and 50 dB SPL with participant’s most preferred background sound off and on, using open-set Dutch consonant-vowel-consonant (CVC) monosyllabic words in a free-field-condition in a sound-treated booth.