Hearing preservation and clinical outcome of 32 consecutive electric acoustic stimulation (EAS) surgeries

Figures & data

Table I. Clinical features of cases undergoing electric acoustic stimulation (EAS).

Case no.	Gender	Age at time of surgery (years)	Operative side	Inheritance mode	Onset age (years)	Responsible gene	Implant	Insertion depth (mm)	Surgeon
1	F	59	R	Sporadic	43	–	PULSAR FLEX24	24	S.U.
2	F	71	R	AD	30	–	PULSAR FLEX24	24	S.U.
3	F	45	R	Sporadic	25	–	PULSAR FLEX24	24	S.U.
4	F	38	L	Sporadic	28	–	PULSAR FLEX24	24	S.U.
5	F	46	R	AD	30	–	PULSAR FLEX24	24	S.U.
6	M	29	R	AD	7	–	PULSAR FLEX24	24	S.U.
7	M	39	L	AD	11	ACTG1	PULSAR FLEX24	24	S.U.
8	F	35	L	Sporadic	25	–	PULSAR FLEX24	24	S.U.
9	M	52	R	Mit	3	Mt.1555A>G	PULSAR FLEX24	24	S.U.
10	F	52	L	Sporadic	48	–	PULSAR FLEX24	24	S.U.
11	F	59	L	Sporadic	38	–	PULSAR FLEX24	24	S.U.
12	F	38	R	AD	13	–	PULSAR FLEX24	24	S.U.
13	F	52	L	Sporadic	37	–	PULSAR FLEX24	24	S.U.
14	M	45	L	Sporadic	35	–	PULSAR FLEX24	24	S.U.
15	M	54	R	Sporadic	52	–	PULSAR FLEX24	24	S.U.
16	M	21	R	AD	7	–	PULSAR FLEX24	24	T.T.
17	F	54	L	Sporadic	32	–	PULSAR FLEX24	24	T.T.
18	M	34	R	Sporadic	7	–	PULSAR FLEX24	24	T.T.
19	F	51	R	Sporadic	3	–	PULSAR FLEX24	24	T.T.
20	F	38	L	Sporadic	18	–	PULSAR FLEX24	24	Y.N.
21	F	58	L	Sporadic	35	–	PULSAR FLEX24	24	Y.N.
22	F	43	R	AR	30	–	PULSAR FLEX24	24	Y.N.
23	M	35	L	AD	10	–	PULSAR FLEX24	24	Y.N.
24	F	69	L	Sporadic	20	–	PULSAR FLEX24	24	H.T./Y.K.
25	M	39	R	Sporadic	30	–	PULSAR FLEX24	24	S.U.
26-1	F	45	L	Sporadic	25	–	PULSAR FLEX24	24	S.U.
26-2	F	48	R	Sporadic	25	–	PULSAR FLEX24	24	S.U.
27-1	F	38	L	AR	10	TMPRSS3	PULSAR FLEX24	24	S.U.
27-2	F	40	R	AR	10	TMPRSS3	PULSAR FLEX24	24	S.U.
28	F	60	R	Sporadic	40	–	Combi 40+ Standard	31.5	S.U.
29	M	68	R	Sporadic	52	–	PULSAR FLEX SOFT	31.5	S.U.
30	F	64	L	Sporadic	42	–	PULSAR FLEX SOFT	31.5	S.U.

AD, autosomal dominant; AR, autosomal recessive; F, female; L, left; M, male; Mit, mitochondrial mutation; R, right.

Figure 1. Hearing preservation results of group 1 with FLEX24 electrode. The lines indicate preoperative, and 1, 3, 6, and 12 months postoperative audiograms. Shadow indicates the audiological criteria for electric acoustic stimulation (EAS) clinical trial (patient nos. 1–24 fulfilling the audiological criteria for EAS, nos. 25–27 not fulfilling the criteria for the clinical trial for EAS).

Figure 2. (A) Average audiogram of group 1. The lines indicate preoperative, 1, 3, 6, and 12 months postoperative audiograms. Note that good hearing preservation could be achieved. (B) Hearing level of group 1 with electric acoustic stimulation (EAS).

Table II. Average hearing thresholds of electric acoustic stimulation (EAS) patients in group 1.

	Air conductive hearing level (dB)							Bone conductive hearing level (dB)
Timing	125 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz	8000 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz
Preoperative	27.8	35.5	52.4	85.2	106.9	110.7	104.1	29.3	42.6	67.9	73.6	64.5
1 month	40.3	53.8	76.7	93.8	107.4	111.2	104.5	35.2	54.8	72.7	73.8	63.9
3 months	38.1	51.2	76.4	95.0	109.7	112.4	104.8	35.9	55.0	73.3	73.6	63.6
6 months	38.8	50.7	78.0	97.5	110.5	112.1	104.5	33.7	56.4	73.6	74.3	63.9
12 months	41.9	55.2	79.8	96.7	109.0	111.6	104.3	37.6	59.3	73.0	73.9	63.9

Figure 3. Hearing preservation results of group 2 (cases with less residual hearing and receiving longer electrodes (no. 28 with standard electrode, nos. 29 and 30 with FLEXSOFT electrode). The lines indicate preoperative, and 1, 3, 6, and 12 months postoperative audiograms. Note that good hearing preservation could be achieved.

Figure 4. (A) Average audiogram of group 2. The lines indicate preoperative, and 1, 3, 6, and 12 months postoperative audiograms. Note that good hearing preservation could be achieved. (B) Hearing level of group 2 with electric acoustic stimulation (EAS).

Table III. Average hearing thresholds of electric acoustic stimulation (EAS) patients in group 2.

	Air conductive hearing level (dB)							Bone conductive hearing level (dB)
Timing	125 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz	8000 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz
Preoperative	43.3	55.0	86.7	110.0	110.0	106.7	105.0	36.7	63.3	75.0	75.0	65.0
1 month	58.3	71.7	88.3	98.3	113.3	113.3	103.3	48.3	58.3	73.3	75.0	65.0
3 months	58.3	68.3	85.0	98.3	115.0	115.0	105.0	53.3	63.3	73.3	75.0	65.0
6 months	45.0	66.7	83.3	106.7	115.0	115.0	105.0	48.3	61.7	75.0	75.0	65.0
12 months	63.3	80.0	95.0	105.0	113.3	113.3	103.3	47.5	62.5	75.0	75.0	65.0

Figure 5. Speech discrimination and perception scores of group 1 (with FLEX24 electrode). Speech discrimination and perception scores were improved postoperatively with electric acoustic stimulation (EAS). SNR, signal-to-noise ratio.

Figure 6. Speech discrimination and perception scores of group 2 (standard electrode or FLEXSOFT electrode with less residual hearing). Speech discrimination and perception scores were improved postoperatively with electric acoustic stimulation (EAS). SNR, signal-to-noise ratio.