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Quality of perceived sound after stapedotomy
Otolaryngology–Head and Neck Surgery (2007) 137, 443-449
ORIGINAL RESEARCH
Quality of perceived sound after stapedotomy Frédérique M.L. Tan, MD, Wilko Grolman, MD, PhD, Rinze A. Tange, MD, PhD, and Wytske J. Fokkens, MD, PhD, Amsterdam, The Netherlands OBJECTIVE: To evaluate the quality of perceived sound in relation to the audiometric result after stapedotomy. STUDY DESIGN: Ninety-eight patients with otosclerosis, who underwent stapedotomy between 2004 and 2005, participated in this retrospective study. Audiometric data were obtained before and after stapedotomy. Patients filled out two questionnaires: the Amsterdam Post Operative Sound Evaluation and the Operation Benefit Profile, which is based on the Glasgow Hearing Aid Benefit Profile. RESULTS: There were 83 responders and 15 nonresponders; 83% indicated that their hearing was now better compared to preoperatively. The sounds that gave the highest percentage of distortion were “high pitched sound” (15%) and “loud sound” (13%). The groups with an air-bone gap of 0 to 10 dB and 10 to 20 dB report a relatively high number of patients who experience distortion. The audiometric data correlate well with the Operation Benefit Score. CONCLUSIONS: Audiometric improvement does not necessarily mean an improvement in perceived sound and vice versa. But the audiometric outcome is significantly related to the patient’s experienced handicap, benefit of the operation, residual difficulty, and overall satisfaction. © 2007 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.
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n people with otosclerosis, stapedotomy is the operation to improve hearing.1 By restoring the mobility of the ossicular chain and the transfer at the stapes footplate, the conduction of sound is restored. This restoration is accomplished by implanting a prosthesis that replaces the stapes and is in contact with the perilymph via a perforation in the stapes footplate. In most clinics, an audiogram is performed both preoperatively and postoperatively. A successful procedure is described as diminishment of air-bone gap and improvement in air conduction. Improved speech reception according to pure tone audiogram is also seen as a parameter of successful outcome. However, patients sometimes state that the quality of sound is suboptimal, although their hearing ability has improved significantly.2 Assessment of quality of life (QOL) after ear surgery is getting more attention nowadays. In previous studies, QOL after ear surgery was measured by assessing the SF-36 and
disease specific Glasgow Benefit Inventory (GBI).3-5 However, little is known about the actual postoperative quality of sound that is perceived by patients who have undergone stapedotomy. How do they experience sound postoperatively? Does it sound good, too soft, too loud, or even distorted? Few questionnaires exist and studies were performed to measure this postoperative quality.2,6,7 In people with conventional hearing aids, the quality of sound and the benefit of a hearing aid are often evaluated by an instrument such as the Glasgow Hearing Aid Benefit Profile (GHABP).8 The primary objective of this study is to determine the quality of perceived sound and patient satisfaction after stapedotomy with an assessment of both existing and newly designed questionnaires. The second objective is to determine if quality of sound is related to postoperative audiometric result.
PATIENTS AND METHODS Ninety-eight consecutive adult patients, who underwent stapedotomy between January 2004 and August 2005, participated in this retrospective questionnaire study. The gender distribution was 33% male and 67% female. The median age of the population was 44 years (range, 19 to 66 years). All 98 patients had clinical evidence of otosclerosis, based on audiometric and peroperative findings. All 98 patients had clinical evidence of otosclerosis, based on audiometric data and clinical findings during surgery. Patients with findings of congenital chain abnormality, disarticulation of the middle ear ossicles or other chain pathoses were excluded from this study. Patient characteristics are listed in Table 1. Stapedotomy was performed via endaural approach and the micropick technique described by Marquet9 was used to create a small fenestra in the stapes footplate. All stapedotomies were performed by the second and third author, who are experienced ear surgeons. Audiometric data, expressed in decibel hearing level (HL), were obtained one week before the operation and two months after stapedotomy. All audiograms were performed by classified personnel according to the ISO-389 (1975)
Received December 5, 2006; accepted March 23, 2007.
0194-5998/$32.00 © 2007 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved. doi:10.1016/j.otohns.2007.03.038
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Table 1 Patient characteristics Variable Gender Male Female Type of surgery Primary First revision Multiple revision Otosclerosis Unilateral Bilateral Prostheses K-Piston Clip àWengen Questionnaire response Responders Nonresponders
N (%) Total N ⫽ 98 32 (33%) 66 (67%) 75 (77%) 17 (17%) 6 (6%) 43 (44%) 55 (56%) 33 (34%) 65 (66%) 83 (85%) 15 (15%)
standard. Audiometry was reported according to American Academy of Otolaryngology–Head and Neck Surgery guidelines,10 except for thresholds at 3 kHZ, which were substituted for 4 kHz in outcomes that concerned boneconduction or air-bone gap. Both air and bone conduction were determined at the same audiometric test. Different studies10,11 have demonstrated that the inclusion of 4 kHz in the pure tone average (PTA) of air (AC) and bone conduction influences the success rate for hearing outcome. To allow comparisons with other studies, we report the 3-frequency PTA (0.5-1-2 kHz) as well as the two different 4-frequency PTAs (0.5-1-2-3 kHz and 0.5-1-2-4 kHz). Patients received two questionnaires: the Amsterdam Post Operative Sound Evaluation (APOSE) and the Operation Benefit Profile (OBP) that is based on the Glasgow Hearing Aid Benefit Profile(GHABP).8 The questionnaires were sent 15 months postoperatively (range, 4 to 23 months). Patients also received a postage-paid envelope to return the questionnaires. The APOSE questionnaire (Appendix 1: See online website: http://journal.entnet.org) was developed by the Amsterdam ear department and consists of two parts. The first part covers the overall postoperative hearing. The second part handles the quality of perceived sound; the postoperative perception of 10 different types of sound are to be judged in terms of “good,” “too loud,” “too soft,” “distorted,” or “other.” The 10 types of sound are “high pitched sound,” “low pitched sound,” “loud sound,” “male voice,” “female voice,” “one’s own voice,” “radio,” “television,” “phone conversations” and “music.” The Operation Benefit Profile (Appendix 2 See online website: http://journal.entnet.org) is based on the Glasgow Hearing Aid Benefit Profile (GHABP)8 in which the benefit of a hearing-aid is tested for various circumstances. The Operation Benefit Profile uses the same questions and situ-
ations as the GHABP, but focuses on the benefit of a stapedotomy rather than of a conservative hearing aid. Therefore, the column that dealt with the proportion of time that the patient wears his/her hearing aid was left out of the OBP questionnaire, as a stapedotomy is permanent and of course not a device that can be worn. As this is a retrospective study, the initial disability column was also excluded as it would rely too much on the patient’s recollection of preoperative disability, which is greatly susceptible to bias. The Operation Benefit Profile assesses four specific listening circumstances that commonly occur in the lives of hearing-impaired clients: watching television, conversation with background noise, conversation without background noise, and group conversation. The circumstances are assessed separately as to four different scales that are listed below. The outcome of the Operation Benefit Profile gives a score from 0 to 100 for each of the scales. The score needs to be interpreted differently for each scale: ●
●
●
●
Handicap scale. The effect or impact on the hearingimpaired listener’s life: 0, not at all; 25, only a little; 50, a moderate amount; 75, quite a lot; 100, very much indeed. Operation benefit scale. The extent to which the operation has contributed in hearing: 0, no use at all; 25, some help; 50, quite helpful; 75, great help; 100, hearing is perfect. Residual disability scale. The postoperative hearing difficulty: 0, no difficulty; 25, only slight difficulty; 50, moderate difficulty; 75, great difficulty; 100, cannot manage at all. Satisfaction scale. The patient’s satisfaction with his or her operation: 0, not satisfied at all; 25, a little satisfied; 50, reasonably satisfied; 75, very satisfied; 100, delighted.
The study was approved by the Institutional Review Board. Statistical analysis was performed in SPSS 12.0.1. To determine significant differences in hearing thresholds before and after surgery, a paired t test was performed. To determine significant differences between the postoperative air conduction bins in relation to the Amsterdam Post Operative Sounds Evaluation and Operation Benefit Profile, a 1-way ANOVA was carried out.
RESULTS Ninety-eight patients were included and 98 ears were operated on. No patients had surgery on both ears during our study period. Preoperative audiometric data were available for all 98 patients. Postoperative audiometric data were available for 97 patients. For 75 patients, it was the first surgery on that particular ear; for 17, it was the first revision; and for six patients, it was a multiple revision. Based on audiometric data, 44% had unilateral otosclerosis, whereas 56% had bilateral otosclerosis. We placed a titanium K-Piston in 33 patients (Heinz Kurz GmbH, Medizintechnik, Dulingen, Germany), and a Clip àWengen in 65 patients (Heinz Kurz GmbH, Medizintechnik).
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Table 2A Audiometric results (air conduction) Air conduction (N ⫽ 97) 95 % CI Frequency KHz
Preoperative
Postoperative
Mean gain (dB)
SD*
Lower
Upper
Sign
0.125 0.25 0.5 1 2 3 4 8 PTA 0.5. 1. 2 PTA 0.5. 1. 2. 3 PTA 0.5. 1. 2. 4 PTA 1. 2. 4
62.3 61.4 56.2 53.6 47.8 45.8 49.2 54.3 52.6 50.9 51.7 50.2
40.7 39.3 36.0 32.9 32.8 32.8 (n⫽96*) 39.4 52.0 33.9 33.7 35.3 35.0
21.5 22.1 20.2 20.7 15.1 13.0 9.8 2.3 18.6 17.2 16.4 15.2
18.1 16.8 17.6 17.0 16.4 19.7 21.3 20.3 15.4 15.2 15.6 16.0
17.9 18.7 16.7 17.3 11.7 9.0 5.5 ⫺1.8 15.5 14.1 13.3 11.9
25.2 25.5 23.7 24.1 18.4 17.0 14.1 6.4 21.7 20.2 19.6 18.4
§ § § § § § §
Audiometric Outcomes Air conduction. The mean pre- and postoperative AC thresholds and the mean gain for each frequency are listed in Table 2A and in Figure 1. All thresholds are given in dB HL. We found a significant difference between the pre- and postoperative air conduction at 125, 250, 500, 1000, 2000, 3000, and 4000 Hz, but no significant difference at 8000 Hz. Furthermore, we measured a significant improvement over all four different calculated pure tone averages (0.5-1-2 kHz, 0.5-1-2-3 kHz, 0.5-1-2-4 kHz, 1-2-4 kHz). The average postoperative airconduction was 35 dB compared with 52 dB preoperatively. Preoperatively 3% of patients had an AC PTA between 20 and 30 dB; 97% had an AC PTA of more than 30 dB. Zero patients had a preoperative AC PTA of less than 20 dB (PTA 0.5,-1-2 and PTA 0.5-1-2-4). Postoperatively 1% of patients had an AC of less than 10 dB, 15% had an AC PTA between 10 and 20 dB, 28% had an AC PTA between 20 and 30 dB, and 56% had an AC PTA of more than 30 dB (PTA 0.5-1-2-4). Improvement of PTA AC of at least 20 dB was seen in 43% of the cases.
§ § § §
Bone conduction. The mean preoperative and postoperative BC pure-tone thresholds, mean gains and PTAs are listed in Table 2B and in Figure 1. At 250 Hz and 4000 Hz, we found a significant worsening of the BC of –3.0 dB and –3.9 dB, respectively. At 2000 Hz, we found a significant improvement of 2.8 dB. This might be due to the counteraction of the Carhart notch. The average preoperative BC was 23 dB compared with 23 dB postoperatively showing no change. Preoperatively 5% of patients had a BC PTA of less than 10 dB. Forty-six percent had a BC PTA between 10 and 20 dB; 30% had a BC PTA between 20 and 30. Finally 19% had a BC PTA of more than 30 dB. (PTA 0.5-1-2-4). Postoperatively 9% of patients had a BC of less than 10 dB, 38% had a BC PTA between 10 and 20 dB, 29% had a BC PTA between 20 and 30 dB, and 24% had an BC PTA of more than 30 dB (PTA 0.5-1-2-4). Air-bone-GAP. Preoperatively, the number of patients in the ABG categories (bins) of (0 to 10), (10 to 20), (20 to 30), (⬎30) dB, is 2 (2%), 19 (19%), 33 (34%), and 44 (45%), respectively (ABG 0.5-1-2-4 kHz). Postoperatively, the number of patients in the following ABG bins (0 to 10), (10 to 20), (20 to 30), (⬎30) dB is 47 (49%), 36 (37%), 10 (10%), and 4 (4%).
APOSE Questionnaire and Operation Benefit Profile Questionnaire
Figure 1
Preoperative and postoperative audiometric result.
The two questionnaires were sent to all 98 patients. We had 83 (85%) responders and 15 (15%) nonresponders. In the nonresponder group, it was determined that we did not have the correct address of three patients and one patient had moved abroad. We tried to contact the remaining 11 patients: 10 patients did not reply to our reminder and did not answer the phone and one patient declared that she did not want to administer the questionnaires because she was too busy.
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Table 2B Audiometric results (bone conduction) Bone conduction (N ⫽ 97) 95 % CI Frequency kHz 0.125 0.25 0.5 1 2 3 4 8 PTA 0.5. 1. 2 PTA 0.5. 1. 2. 3 PTA 0.5. 1. 2. 4 PTA 1. 2. 4
Preoperative
Postoperative
Mean gain (dB)
SD*
Lower
Upper
Sign
4.9 16.3 20.1 29.7 24.8 (^n⫽3) 23.8
7.8 18.3 21.1 27.0 31.3 (^n⫽7) 27.6
⫺3.0 ⫺2.0 ⫺1.1 2.8 ⫺6.5 ⫺3.9
9.7 10.1 11.7 11.5 20.5 13.4
⫺5.0 ⫺4.0 ⫺3.4 0.5 ⫺14.6 ⫺6.6
⫺1.0 0.1 1.3 5.1 1.6 ⫺1.2
‡
22.0
22.0
0.0
8.5
⫺1.7
1.7
22.5 24.5
23.3 25.0
⫺0.9 ⫺0.5
8.6 9.7
⫺2.6 ⫺2.4
0.9 1.5
‡ ‡
*Standard deviation. †CI, 95% confidence interval. ‡P ⬍ 0.05. §P ⬍ 0.001.
Operation Benefit Profile Questionnaire. The Operation Benefit Profile provides a score between 0 and 100 for each of the four scales. The average handicap outcome was 25 (median), which means that postoperatively the hearing worried, annoyed, or upset the patient “only a little.” The median operation benefit was 75, which meant that the operation had been “a great help.” The residual disability score (median) was 46, which indicated that since the operation the patients had “slight to moderate difficulty” in different circumstances. The overall satisfaction score was 75 (median), which may be interpreted that the patients were “very satisfied.”
APOSE questionnaire. The first part of the APOSE covers the overall postoperative hearing. Eighty-three percent indicated that their hearing was now better compared with preoperatively. Eleven percent indicated that the hearing had worsened, and 6% said it had not changed at all. The second part deals with the postoperative perception of sounds. The outcomes are listed in Table 3. A good perception of sounds was seen in more than 50% of the patients. The top four types of sound with highest percentage of good perception were female voice, own voice, radio, and music. The sounds that gave the highest percentage of distortion were high pitched sound (15%), loud sound (13%), low pitched sound (11%), and music (10%). Too soft perception was experienced namely in low pitched sound (30%), male voice (25%), television (24%), phone conversation (23%), and radio (20%). A too loud perception was mostly experienced by loud sounds (26%).
Audiometric outcome versus APOSE questionnaire. When comparing the audiometric data with the first section of the APOSE questionnaire, it can be seen that it does not correlate well (Fig 2). From the 10 patients who had gained over
Table 3 Perception of sound postoperatively (APOSE part II) Sound High pitched sound Low pitched sound Loud sound Male voice Female voice Own voice Radio Television Phone conversation Music
Good N (%) 51 43 41 50 57 63 56 48 48 51
(63%) (53%) (50%) (61%) (71%) (79%) (69%) (59%) (59%) (64%)
Too loud N (%)
Too soft N (%)
4 0 21 2 0 5 0 3 3 4
10 24 5 20 14 3 16 20 19 13
(5%) (0%) (26%) (3%) (0%) (6%) (0%) (4%) (4%) (5%)
(12%) (30%) (6%) (25%) (17%) (4%) (20%) (24%) (23%) (17%)
Distorted N (%) 12 9 11 6 6 7 4 6 8 8
(15%) (11%) (13%) (7%) (7%) (9%) (5%) (7%) (9%) (10%)
Other N (%) 4 5 4 3 4 2 5 5 4 3
(5%) (6%) (5%) (4%) (5%) (2%) (6%) (6%) (5%) (4%)
Responders 81 81 82 81 81 80 81 82 82 79
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30 dB in AC, all indicated that their hearing was better. However, from the 26 patients who had gained between 20 and 30 dB, 25 indicated that their hearing was better, but one stated it was worse than preoperatively. Twenty-four patients had an AC gain between 10 and 20 dB; 21 said their hearing had improved, but two said it was worse and one stated that it had stayed unchanged. From the 14 patients who had gained between 0 and 10 dB, 10 indicated that the hearing was better, two said it was worse and two stated that it had not changed. From the eight patients who did not have AC gain over 0.5-, 1-, 2-, 4-kHz, two patients still experienced their hearing as better, four as worse, and two as unaltered. When comparing the audiometric data with quality of sound, we evaluated the postoperative air-bone gap (ABG) with the patient’s opinion on his or her perception of sound. We specifically chose to look at the ABG instead of postoperative AC, as distortion of sound may be caused by factors with respect to the prosthesis and has a specific influence on the ABG closure. In the groups of 0 to 10 dB and 10 to 20 dB postoperative ABG, a relatively high number of patients can be found that experience distortion (Figs 3 and 4). Audiometric outcome versus Operation Benefit Profile. When the audiometric data are compared with the Operation Benefit Profile score, a relationship can be seen (Fig 5). When looking at the relationship between the handicap score (impact on patient’s life) and the postoperative AC, it can be seen that there is a significant difference in handicap score between the groups 20 to 30 dB and ⬎30 dB (P ⫽ 0.003), which means that patients with an AC loss of more than 30 dB experienced a greater handicap than patients with less hearing loss. As the groups 0 to 10 dB and 10 to 20 dB each only contained one person, no valid statement can be made about their intergroup difference. Still the mean handicap score of the ⬍30 dB AC group was only 23.5, which
Figure 2 Patient’s opinion on postoperative hearing compared to air conduction gain (PTA, 0.5-1-2-4 kHz).
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Figure 3
Quality of perception of high pitched sound.
indicated that their hearing had only a little impact on their lives. Patients with a postoperative AC ⬎30 dB were shown to have significantly less benefit from their operation than patients with a better postoperative air conduction (20 to 30 dB vs ⬎30 dB; P ⫽ 0.003). The difficulty patients still have in different circumstances (residual score) relates well to the audiometric outcome. An increasing residual score is seen when the postoperative AC is worse. Overall patient satisfaction clearly drops when the AC is greater than 30 dB. Their mean score is 36, which indicates little to reasonable
Figure 4
Quality of perception of loud sound.
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Figure 5
Operation Benefit Profile Score in relationship to postoperative air conduction (PTA AC, 0.5-1-2-4 kHz).
satisfaction. No significant difference in satisfaction can be seen between the groups of 10 to 20 dB and 20 to 30 dB, who were between reasonably and very satisfied with a mean score of 66.
DISCUSSION A successful outcome of stapedotomy is in literature often described as an audiometric improvement of PTA and diminishment of ABG. In several studies,12-15 success rates of 78% to 80% are shown for a postoperative ABG of ⬍10 dB and 94% to 97% for an ABG ⬍20 dB. Revision stapes surgery is less likely to be successful than the primary operation. Closure of ABG to ⬍10 dB is then reported to be around 52%.16 Quality of life after ear surgery has been assessed by some authors and shows a significant change in SF-36 for six of the eight fields but is measured for all types of ear surgery together and not specified for stapedotomy alone.3 In this study, we found that the postoperative audiometric result is not always related to the quality of sound; some patients with good postoperative PTAs and ABGs do have problems with the quality of sound, whereas some patients with less successful PTAs and ABGs have no complaints about their sound perception. Furthermore, considerable audiometric improvement (AC GAIN), is not always experienced as such by patients. This is also true for audiometric worsening or unaltered state, which can still be experienced as an improvement. Different theories exist about the aforementioned. First of all, the postoperative perception of sound may be different from the preoperative perception. Patients will need to get used to the loudness and the new character of sound in general. It is seen that within the early postoperative period patients get normally accustomed to this new perception.2 Second, a physical explanation can be named. For an optimal postoperative sound conduction via the ossicular chain and prosthesis to the inner ear, a smooth movement of the prosthesis in the remnants of the stapes footplate is required. Suboptimal position of the prosthesis might give loss of sound quality and even distortion of sound, although the audiometric outcome may be good.
In the third place, otosclerosis does not only affect the middle ear, but also the inner ear. Although stapes surgery may restore the transfer of sound at the footplate, possible negative effect on the cochlea is not completely clear.2 All studies assessing quality of life or quality of sound in our case are subject to a number of limitations. First, a certain response bias may occur. Patients may report a more positive result to ensure that their relationship with the physician and treatment does not change. It can be thought that patients with a good postoperative outcome are more likely to participate in a questionnaire study than patients with a negative outcome, as they are willing to do the surgeon a favor in return. On the other hand, unsatisfied patients may want to express their disappointment and may give a negative answer to every question to let the surgeon know that the operation was unsuccessful and that it has major implications on the patient’s life. In our study, the audiometric postoperative result of the nonresponders was equal to the audiometric result of the responders. However, quality of sound and possible negative feelings toward it cannot be assessed with pure-tone audiometry. Another form of response bias in our study might be that patients have different expectations of the operation. For that reason patients with great expectations might end up with slight disappointment and therefore negative answers, whereas others, who expect only “some” improvement from the operation, might give a too-positive impression. Furthermore, a certain placebo effect might be present in some patients. A third limitation of quality of life or quality of sound studies is that the used questionnaires may be inappropriate to capture the desired information and therefore may not reflect the true quality of life or sound.17 A specific limitation of this study is that a newly designed questionnaire is used because hardly any questionnaires exist to test the true quality of sound after stapedotomy. Thus it is difficult to compare our outcomes with other studies. As this is a retrospective questionnaire study, we cannot compare the postoperative quality of sound with the preoperative situation. Therefore, we are planning a prospective study in which this comparison will be possible. Furthermore the designed APOSE questionnaire will also be
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tested in patients with hearing aids as in a control group to allow for comparisons in the future. Despite the aforementioned limitations, this quality of sound study gives a good impression of the perceived sound after stapedotomy and the difference in perception between patients. It shows that an audiometric improvement does not necessarily mean an improvement in perceived sound and vice versa. But is also shows that the audiometric outcome is well related to the patient’s experienced handicap, benefit of the operation, residual difficulty, and overall satisfaction.
ACKNOWLEDGMENT We wish to thank Bert Maat for his help in collecting the audiometric results, Ingrid van Tessel for her help in collecting the questionnaires, and Robert Lindeboom for his advice concerning the statistical analysis of the data.
AUTHOR INFORMATION From the Department of Otorhinolaryngology–Head and Neck Surgery, Academic Medical Center, University of Amsterdam, The Netherlands. Corresponding author: Wilko Grolman, MD, Department of Otolaryngology, Academic Medical Center, University of Amsterdam, Postbus 22660, 1100 DD Amsterdam, The Netherlands. E-mail address: [email protected].
FINANCIAL DISCLOSURE None.
REFERENCES 1. Shea JJ, Jr. Fenestration of the oval window. Ann Otol Rhinol Laryngol 1958;67(4):932–51.
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2. Lundman L, Mendel L, Bagger-Sjoback D, et al. Hearing in patients operated unilaterally for otosclerosis: self-assessment of hearing and audiometric results. Acta Otolaryngol 1999;119(4):453– 8. 3. Morzaria S, Westerberg BD, Anzarut A. Quality of life following ear surgery measured by the 36-item Short Form Health Survey and the Glasgow Benefit Inventory. J Otolaryngol 2003;32(5):323–7. 4. Chandarana S, Parnes L, Agrawal S, et al. Quality of life following small fenestra stapedotomy. Ann Otol Rhinol Laryngol 2005;114(6): 472–7. 5. Stewart MG, Coker NJ, Jenkins HA, et al. Outcomes and quality of life in conductive hearing loss. Otolaryngol Head Neck Surg 2000;123(5): 527–32. 6. Meyer SE, Megerian CA. Patients’ perceived outcomes after stapedectomy for otosclerosis. Ear Nose Throat J 2000;79(11):846 –2, 854. 7. Ramsay H, Karkkainen J, Palva T. Success in surgery for otosclerosis: hearing improvement and other indicators. Am J Otolaryngol 1997; 18(1):23– 8. 8. Gatehouse S. A self-report outcome measure for the evaluation of hearing aid fittings and services. Health Bull (Edinb) 1999;57(6):424 – 36. 9. Marquet J. “Stapedotomy” technique and results. Am J Otol 1985; 6(1):63–7. 10. Committee on Hearing and Equilibrium guidelines for the evaluation of results of treatment of conductive hearing loss. Otolaryngol Head Neck Surg 1995;113(3):186 –7. 11. Berliner KI, Doyle KJ, Goldenberg RA. Reporting operative hearing results in stapes surgery: does choice of outcome measure make a difference? Am J Otol 1996;17(4):521– 8. 12. Zuur CL, de Bruijn AJ, Lindeboom R, et al. Retrospective analysis of early postoperative hearing results obtained after stapedotomy with implantation of a new titanium stapes prosthesis. Otol Neurotol 2003; 24(6):863–7. 13. Somers T, Govaerts P, Marquet T, et al. Statistical analysis of otosclerosis surgery performed by Jean Marquet. Ann Otol Rhinol Laryngol 1994;103(12):945–51. 14. Raske M, Welling JD, Gillum T, et al. Long-term stapedectomy results with the McGee stapes prosthesis. Laryngoscope 2001;111(11 Pt 1): 2060 –3. 15. de Bruijn AJ, Tange RA, Dreschler WA. Comparison of stapes prostheses: a retrospective analysis of individual audiometric results obtained after stapedotomy by implantation of a gold and a teflon piston. Am J Otol 1999;20(5):573– 80. 16. Gros A, Vatovec J, Zargi M, et al. Success rate in revision stapes surgery for otosclerosis. Otol Neurotol 2005;26(6):1143– 8. 17. Hunt SM, McKenna SP. Validating the SF-36. BMJ 1992;305(6854): 645.
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APPENDIX 1 THE AMSTERDAM POST OPERATIVE SOUND EVALUATION Instructions: Please choose only one response to each question PART 1 How is your hearing now compared to before the operation? □ better □ worse □ unchanged PART 2 Since the operation, how is your perception of the following sounds? High pitched sound □ good □ too loud Low pitched sound □ good □ too loud Loud sound □ good □ too loud Male voice □ good □ too loud Female voice □ good □ too loud One’s own voice □ good □ too loud Radio □ good □ too loud Television □ good □ too loud Phone conversation □ good □ too loud Music □ good □ too loud
□ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other
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APPENDIX 2 THE OPERATION BENEFIT PROFILE (BASED ON THE GLASGOW HEARING AID BENEFIT PROFILE) Does this situation happen in your life? LISTENING TO THE TELEVISION WITH OTHER FAMILY OR FRIENDS WHEN THE VOLUME IS ADJUSTED TO SUIT OTHER PEOPLE 0 ___ No 1 ___ Yes For this situation, how In this situation, since In this situation, how How much does any satisfied are you with your the operation how much has your difficulty in this situation operation? much difficulty do you operation helped you? worry, annoy, or upset still have? you? 0___N/A 0___N/A 0___N/A 0___N/A 1___Not at all 1___No use at all 1___No difficulty 1___Not satisfied at all 2___Only a little 2___Some help 2___Only slight difficulty 2___A little satisfied 3___A moderate amount 3___Quite helpful 3___Moderate difficulty 3___Reasonably satisfied 4___Quite a lot 4___Great help 4___Great difficulty 4___Very satisfied 5___Very much indeed 5___Hearing is perfect 5___Cannot manage at 5___Delighted all Does this situation happen in NO BACKGROUND NOISE 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? HAVING A CONVERSATION WITH ONE OTHER PERSON WHEN THERE IS
Does this situation happen in 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? CARRYING ON A CONVERSATION IN A BUSY STREET OR SHOP
Does this situation happen in 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? HAVING A CONVERSATION WITH SEVERAL PEOPLE IN A GROUP
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted
ORIGINAL RESEARCH
Quality of perceived sound after stapedotomy Frédérique M.L. Tan, MD, Wilko Grolman, MD, PhD, Rinze A. Tange, MD, PhD, and Wytske J. Fokkens, MD, PhD, Amsterdam, The Netherlands OBJECTIVE: To evaluate the quality of perceived sound in relation to the audiometric result after stapedotomy. STUDY DESIGN: Ninety-eight patients with otosclerosis, who underwent stapedotomy between 2004 and 2005, participated in this retrospective study. Audiometric data were obtained before and after stapedotomy. Patients filled out two questionnaires: the Amsterdam Post Operative Sound Evaluation and the Operation Benefit Profile, which is based on the Glasgow Hearing Aid Benefit Profile. RESULTS: There were 83 responders and 15 nonresponders; 83% indicated that their hearing was now better compared to preoperatively. The sounds that gave the highest percentage of distortion were “high pitched sound” (15%) and “loud sound” (13%). The groups with an air-bone gap of 0 to 10 dB and 10 to 20 dB report a relatively high number of patients who experience distortion. The audiometric data correlate well with the Operation Benefit Score. CONCLUSIONS: Audiometric improvement does not necessarily mean an improvement in perceived sound and vice versa. But the audiometric outcome is significantly related to the patient’s experienced handicap, benefit of the operation, residual difficulty, and overall satisfaction. © 2007 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.
I
n people with otosclerosis, stapedotomy is the operation to improve hearing.1 By restoring the mobility of the ossicular chain and the transfer at the stapes footplate, the conduction of sound is restored. This restoration is accomplished by implanting a prosthesis that replaces the stapes and is in contact with the perilymph via a perforation in the stapes footplate. In most clinics, an audiogram is performed both preoperatively and postoperatively. A successful procedure is described as diminishment of air-bone gap and improvement in air conduction. Improved speech reception according to pure tone audiogram is also seen as a parameter of successful outcome. However, patients sometimes state that the quality of sound is suboptimal, although their hearing ability has improved significantly.2 Assessment of quality of life (QOL) after ear surgery is getting more attention nowadays. In previous studies, QOL after ear surgery was measured by assessing the SF-36 and
disease specific Glasgow Benefit Inventory (GBI).3-5 However, little is known about the actual postoperative quality of sound that is perceived by patients who have undergone stapedotomy. How do they experience sound postoperatively? Does it sound good, too soft, too loud, or even distorted? Few questionnaires exist and studies were performed to measure this postoperative quality.2,6,7 In people with conventional hearing aids, the quality of sound and the benefit of a hearing aid are often evaluated by an instrument such as the Glasgow Hearing Aid Benefit Profile (GHABP).8 The primary objective of this study is to determine the quality of perceived sound and patient satisfaction after stapedotomy with an assessment of both existing and newly designed questionnaires. The second objective is to determine if quality of sound is related to postoperative audiometric result.
PATIENTS AND METHODS Ninety-eight consecutive adult patients, who underwent stapedotomy between January 2004 and August 2005, participated in this retrospective questionnaire study. The gender distribution was 33% male and 67% female. The median age of the population was 44 years (range, 19 to 66 years). All 98 patients had clinical evidence of otosclerosis, based on audiometric and peroperative findings. All 98 patients had clinical evidence of otosclerosis, based on audiometric data and clinical findings during surgery. Patients with findings of congenital chain abnormality, disarticulation of the middle ear ossicles or other chain pathoses were excluded from this study. Patient characteristics are listed in Table 1. Stapedotomy was performed via endaural approach and the micropick technique described by Marquet9 was used to create a small fenestra in the stapes footplate. All stapedotomies were performed by the second and third author, who are experienced ear surgeons. Audiometric data, expressed in decibel hearing level (HL), were obtained one week before the operation and two months after stapedotomy. All audiograms were performed by classified personnel according to the ISO-389 (1975)
Received December 5, 2006; accepted March 23, 2007.
0194-5998/$32.00 © 2007 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved. doi:10.1016/j.otohns.2007.03.038
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Table 1 Patient characteristics Variable Gender Male Female Type of surgery Primary First revision Multiple revision Otosclerosis Unilateral Bilateral Prostheses K-Piston Clip àWengen Questionnaire response Responders Nonresponders
N (%) Total N ⫽ 98 32 (33%) 66 (67%) 75 (77%) 17 (17%) 6 (6%) 43 (44%) 55 (56%) 33 (34%) 65 (66%) 83 (85%) 15 (15%)
standard. Audiometry was reported according to American Academy of Otolaryngology–Head and Neck Surgery guidelines,10 except for thresholds at 3 kHZ, which were substituted for 4 kHz in outcomes that concerned boneconduction or air-bone gap. Both air and bone conduction were determined at the same audiometric test. Different studies10,11 have demonstrated that the inclusion of 4 kHz in the pure tone average (PTA) of air (AC) and bone conduction influences the success rate for hearing outcome. To allow comparisons with other studies, we report the 3-frequency PTA (0.5-1-2 kHz) as well as the two different 4-frequency PTAs (0.5-1-2-3 kHz and 0.5-1-2-4 kHz). Patients received two questionnaires: the Amsterdam Post Operative Sound Evaluation (APOSE) and the Operation Benefit Profile (OBP) that is based on the Glasgow Hearing Aid Benefit Profile(GHABP).8 The questionnaires were sent 15 months postoperatively (range, 4 to 23 months). Patients also received a postage-paid envelope to return the questionnaires. The APOSE questionnaire (Appendix 1: See online website: http://journal.entnet.org) was developed by the Amsterdam ear department and consists of two parts. The first part covers the overall postoperative hearing. The second part handles the quality of perceived sound; the postoperative perception of 10 different types of sound are to be judged in terms of “good,” “too loud,” “too soft,” “distorted,” or “other.” The 10 types of sound are “high pitched sound,” “low pitched sound,” “loud sound,” “male voice,” “female voice,” “one’s own voice,” “radio,” “television,” “phone conversations” and “music.” The Operation Benefit Profile (Appendix 2 See online website: http://journal.entnet.org) is based on the Glasgow Hearing Aid Benefit Profile (GHABP)8 in which the benefit of a hearing-aid is tested for various circumstances. The Operation Benefit Profile uses the same questions and situ-
ations as the GHABP, but focuses on the benefit of a stapedotomy rather than of a conservative hearing aid. Therefore, the column that dealt with the proportion of time that the patient wears his/her hearing aid was left out of the OBP questionnaire, as a stapedotomy is permanent and of course not a device that can be worn. As this is a retrospective study, the initial disability column was also excluded as it would rely too much on the patient’s recollection of preoperative disability, which is greatly susceptible to bias. The Operation Benefit Profile assesses four specific listening circumstances that commonly occur in the lives of hearing-impaired clients: watching television, conversation with background noise, conversation without background noise, and group conversation. The circumstances are assessed separately as to four different scales that are listed below. The outcome of the Operation Benefit Profile gives a score from 0 to 100 for each of the scales. The score needs to be interpreted differently for each scale: ●
●
●
●
Handicap scale. The effect or impact on the hearingimpaired listener’s life: 0, not at all; 25, only a little; 50, a moderate amount; 75, quite a lot; 100, very much indeed. Operation benefit scale. The extent to which the operation has contributed in hearing: 0, no use at all; 25, some help; 50, quite helpful; 75, great help; 100, hearing is perfect. Residual disability scale. The postoperative hearing difficulty: 0, no difficulty; 25, only slight difficulty; 50, moderate difficulty; 75, great difficulty; 100, cannot manage at all. Satisfaction scale. The patient’s satisfaction with his or her operation: 0, not satisfied at all; 25, a little satisfied; 50, reasonably satisfied; 75, very satisfied; 100, delighted.
The study was approved by the Institutional Review Board. Statistical analysis was performed in SPSS 12.0.1. To determine significant differences in hearing thresholds before and after surgery, a paired t test was performed. To determine significant differences between the postoperative air conduction bins in relation to the Amsterdam Post Operative Sounds Evaluation and Operation Benefit Profile, a 1-way ANOVA was carried out.
RESULTS Ninety-eight patients were included and 98 ears were operated on. No patients had surgery on both ears during our study period. Preoperative audiometric data were available for all 98 patients. Postoperative audiometric data were available for 97 patients. For 75 patients, it was the first surgery on that particular ear; for 17, it was the first revision; and for six patients, it was a multiple revision. Based on audiometric data, 44% had unilateral otosclerosis, whereas 56% had bilateral otosclerosis. We placed a titanium K-Piston in 33 patients (Heinz Kurz GmbH, Medizintechnik, Dulingen, Germany), and a Clip àWengen in 65 patients (Heinz Kurz GmbH, Medizintechnik).
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Table 2A Audiometric results (air conduction) Air conduction (N ⫽ 97) 95 % CI Frequency KHz
Preoperative
Postoperative
Mean gain (dB)
SD*
Lower
Upper
Sign
0.125 0.25 0.5 1 2 3 4 8 PTA 0.5. 1. 2 PTA 0.5. 1. 2. 3 PTA 0.5. 1. 2. 4 PTA 1. 2. 4
62.3 61.4 56.2 53.6 47.8 45.8 49.2 54.3 52.6 50.9 51.7 50.2
40.7 39.3 36.0 32.9 32.8 32.8 (n⫽96*) 39.4 52.0 33.9 33.7 35.3 35.0
21.5 22.1 20.2 20.7 15.1 13.0 9.8 2.3 18.6 17.2 16.4 15.2
18.1 16.8 17.6 17.0 16.4 19.7 21.3 20.3 15.4 15.2 15.6 16.0
17.9 18.7 16.7 17.3 11.7 9.0 5.5 ⫺1.8 15.5 14.1 13.3 11.9
25.2 25.5 23.7 24.1 18.4 17.0 14.1 6.4 21.7 20.2 19.6 18.4
§ § § § § § §
Audiometric Outcomes Air conduction. The mean pre- and postoperative AC thresholds and the mean gain for each frequency are listed in Table 2A and in Figure 1. All thresholds are given in dB HL. We found a significant difference between the pre- and postoperative air conduction at 125, 250, 500, 1000, 2000, 3000, and 4000 Hz, but no significant difference at 8000 Hz. Furthermore, we measured a significant improvement over all four different calculated pure tone averages (0.5-1-2 kHz, 0.5-1-2-3 kHz, 0.5-1-2-4 kHz, 1-2-4 kHz). The average postoperative airconduction was 35 dB compared with 52 dB preoperatively. Preoperatively 3% of patients had an AC PTA between 20 and 30 dB; 97% had an AC PTA of more than 30 dB. Zero patients had a preoperative AC PTA of less than 20 dB (PTA 0.5,-1-2 and PTA 0.5-1-2-4). Postoperatively 1% of patients had an AC of less than 10 dB, 15% had an AC PTA between 10 and 20 dB, 28% had an AC PTA between 20 and 30 dB, and 56% had an AC PTA of more than 30 dB (PTA 0.5-1-2-4). Improvement of PTA AC of at least 20 dB was seen in 43% of the cases.
§ § § §
Bone conduction. The mean preoperative and postoperative BC pure-tone thresholds, mean gains and PTAs are listed in Table 2B and in Figure 1. At 250 Hz and 4000 Hz, we found a significant worsening of the BC of –3.0 dB and –3.9 dB, respectively. At 2000 Hz, we found a significant improvement of 2.8 dB. This might be due to the counteraction of the Carhart notch. The average preoperative BC was 23 dB compared with 23 dB postoperatively showing no change. Preoperatively 5% of patients had a BC PTA of less than 10 dB. Forty-six percent had a BC PTA between 10 and 20 dB; 30% had a BC PTA between 20 and 30. Finally 19% had a BC PTA of more than 30 dB. (PTA 0.5-1-2-4). Postoperatively 9% of patients had a BC of less than 10 dB, 38% had a BC PTA between 10 and 20 dB, 29% had a BC PTA between 20 and 30 dB, and 24% had an BC PTA of more than 30 dB (PTA 0.5-1-2-4). Air-bone-GAP. Preoperatively, the number of patients in the ABG categories (bins) of (0 to 10), (10 to 20), (20 to 30), (⬎30) dB, is 2 (2%), 19 (19%), 33 (34%), and 44 (45%), respectively (ABG 0.5-1-2-4 kHz). Postoperatively, the number of patients in the following ABG bins (0 to 10), (10 to 20), (20 to 30), (⬎30) dB is 47 (49%), 36 (37%), 10 (10%), and 4 (4%).
APOSE Questionnaire and Operation Benefit Profile Questionnaire
Figure 1
Preoperative and postoperative audiometric result.
The two questionnaires were sent to all 98 patients. We had 83 (85%) responders and 15 (15%) nonresponders. In the nonresponder group, it was determined that we did not have the correct address of three patients and one patient had moved abroad. We tried to contact the remaining 11 patients: 10 patients did not reply to our reminder and did not answer the phone and one patient declared that she did not want to administer the questionnaires because she was too busy.
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Table 2B Audiometric results (bone conduction) Bone conduction (N ⫽ 97) 95 % CI Frequency kHz 0.125 0.25 0.5 1 2 3 4 8 PTA 0.5. 1. 2 PTA 0.5. 1. 2. 3 PTA 0.5. 1. 2. 4 PTA 1. 2. 4
Preoperative
Postoperative
Mean gain (dB)
SD*
Lower
Upper
Sign
4.9 16.3 20.1 29.7 24.8 (^n⫽3) 23.8
7.8 18.3 21.1 27.0 31.3 (^n⫽7) 27.6
⫺3.0 ⫺2.0 ⫺1.1 2.8 ⫺6.5 ⫺3.9
9.7 10.1 11.7 11.5 20.5 13.4
⫺5.0 ⫺4.0 ⫺3.4 0.5 ⫺14.6 ⫺6.6
⫺1.0 0.1 1.3 5.1 1.6 ⫺1.2
‡
22.0
22.0
0.0
8.5
⫺1.7
1.7
22.5 24.5
23.3 25.0
⫺0.9 ⫺0.5
8.6 9.7
⫺2.6 ⫺2.4
0.9 1.5
‡ ‡
*Standard deviation. †CI, 95% confidence interval. ‡P ⬍ 0.05. §P ⬍ 0.001.
Operation Benefit Profile Questionnaire. The Operation Benefit Profile provides a score between 0 and 100 for each of the four scales. The average handicap outcome was 25 (median), which means that postoperatively the hearing worried, annoyed, or upset the patient “only a little.” The median operation benefit was 75, which meant that the operation had been “a great help.” The residual disability score (median) was 46, which indicated that since the operation the patients had “slight to moderate difficulty” in different circumstances. The overall satisfaction score was 75 (median), which may be interpreted that the patients were “very satisfied.”
APOSE questionnaire. The first part of the APOSE covers the overall postoperative hearing. Eighty-three percent indicated that their hearing was now better compared with preoperatively. Eleven percent indicated that the hearing had worsened, and 6% said it had not changed at all. The second part deals with the postoperative perception of sounds. The outcomes are listed in Table 3. A good perception of sounds was seen in more than 50% of the patients. The top four types of sound with highest percentage of good perception were female voice, own voice, radio, and music. The sounds that gave the highest percentage of distortion were high pitched sound (15%), loud sound (13%), low pitched sound (11%), and music (10%). Too soft perception was experienced namely in low pitched sound (30%), male voice (25%), television (24%), phone conversation (23%), and radio (20%). A too loud perception was mostly experienced by loud sounds (26%).
Audiometric outcome versus APOSE questionnaire. When comparing the audiometric data with the first section of the APOSE questionnaire, it can be seen that it does not correlate well (Fig 2). From the 10 patients who had gained over
Table 3 Perception of sound postoperatively (APOSE part II) Sound High pitched sound Low pitched sound Loud sound Male voice Female voice Own voice Radio Television Phone conversation Music
Good N (%) 51 43 41 50 57 63 56 48 48 51
(63%) (53%) (50%) (61%) (71%) (79%) (69%) (59%) (59%) (64%)
Too loud N (%)
Too soft N (%)
4 0 21 2 0 5 0 3 3 4
10 24 5 20 14 3 16 20 19 13
(5%) (0%) (26%) (3%) (0%) (6%) (0%) (4%) (4%) (5%)
(12%) (30%) (6%) (25%) (17%) (4%) (20%) (24%) (23%) (17%)
Distorted N (%) 12 9 11 6 6 7 4 6 8 8
(15%) (11%) (13%) (7%) (7%) (9%) (5%) (7%) (9%) (10%)
Other N (%) 4 5 4 3 4 2 5 5 4 3
(5%) (6%) (5%) (4%) (5%) (2%) (6%) (6%) (5%) (4%)
Responders 81 81 82 81 81 80 81 82 82 79
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30 dB in AC, all indicated that their hearing was better. However, from the 26 patients who had gained between 20 and 30 dB, 25 indicated that their hearing was better, but one stated it was worse than preoperatively. Twenty-four patients had an AC gain between 10 and 20 dB; 21 said their hearing had improved, but two said it was worse and one stated that it had stayed unchanged. From the 14 patients who had gained between 0 and 10 dB, 10 indicated that the hearing was better, two said it was worse and two stated that it had not changed. From the eight patients who did not have AC gain over 0.5-, 1-, 2-, 4-kHz, two patients still experienced their hearing as better, four as worse, and two as unaltered. When comparing the audiometric data with quality of sound, we evaluated the postoperative air-bone gap (ABG) with the patient’s opinion on his or her perception of sound. We specifically chose to look at the ABG instead of postoperative AC, as distortion of sound may be caused by factors with respect to the prosthesis and has a specific influence on the ABG closure. In the groups of 0 to 10 dB and 10 to 20 dB postoperative ABG, a relatively high number of patients can be found that experience distortion (Figs 3 and 4). Audiometric outcome versus Operation Benefit Profile. When the audiometric data are compared with the Operation Benefit Profile score, a relationship can be seen (Fig 5). When looking at the relationship between the handicap score (impact on patient’s life) and the postoperative AC, it can be seen that there is a significant difference in handicap score between the groups 20 to 30 dB and ⬎30 dB (P ⫽ 0.003), which means that patients with an AC loss of more than 30 dB experienced a greater handicap than patients with less hearing loss. As the groups 0 to 10 dB and 10 to 20 dB each only contained one person, no valid statement can be made about their intergroup difference. Still the mean handicap score of the ⬍30 dB AC group was only 23.5, which
Figure 2 Patient’s opinion on postoperative hearing compared to air conduction gain (PTA, 0.5-1-2-4 kHz).
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Figure 3
Quality of perception of high pitched sound.
indicated that their hearing had only a little impact on their lives. Patients with a postoperative AC ⬎30 dB were shown to have significantly less benefit from their operation than patients with a better postoperative air conduction (20 to 30 dB vs ⬎30 dB; P ⫽ 0.003). The difficulty patients still have in different circumstances (residual score) relates well to the audiometric outcome. An increasing residual score is seen when the postoperative AC is worse. Overall patient satisfaction clearly drops when the AC is greater than 30 dB. Their mean score is 36, which indicates little to reasonable
Figure 4
Quality of perception of loud sound.
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Figure 5
Operation Benefit Profile Score in relationship to postoperative air conduction (PTA AC, 0.5-1-2-4 kHz).
satisfaction. No significant difference in satisfaction can be seen between the groups of 10 to 20 dB and 20 to 30 dB, who were between reasonably and very satisfied with a mean score of 66.
DISCUSSION A successful outcome of stapedotomy is in literature often described as an audiometric improvement of PTA and diminishment of ABG. In several studies,12-15 success rates of 78% to 80% are shown for a postoperative ABG of ⬍10 dB and 94% to 97% for an ABG ⬍20 dB. Revision stapes surgery is less likely to be successful than the primary operation. Closure of ABG to ⬍10 dB is then reported to be around 52%.16 Quality of life after ear surgery has been assessed by some authors and shows a significant change in SF-36 for six of the eight fields but is measured for all types of ear surgery together and not specified for stapedotomy alone.3 In this study, we found that the postoperative audiometric result is not always related to the quality of sound; some patients with good postoperative PTAs and ABGs do have problems with the quality of sound, whereas some patients with less successful PTAs and ABGs have no complaints about their sound perception. Furthermore, considerable audiometric improvement (AC GAIN), is not always experienced as such by patients. This is also true for audiometric worsening or unaltered state, which can still be experienced as an improvement. Different theories exist about the aforementioned. First of all, the postoperative perception of sound may be different from the preoperative perception. Patients will need to get used to the loudness and the new character of sound in general. It is seen that within the early postoperative period patients get normally accustomed to this new perception.2 Second, a physical explanation can be named. For an optimal postoperative sound conduction via the ossicular chain and prosthesis to the inner ear, a smooth movement of the prosthesis in the remnants of the stapes footplate is required. Suboptimal position of the prosthesis might give loss of sound quality and even distortion of sound, although the audiometric outcome may be good.
In the third place, otosclerosis does not only affect the middle ear, but also the inner ear. Although stapes surgery may restore the transfer of sound at the footplate, possible negative effect on the cochlea is not completely clear.2 All studies assessing quality of life or quality of sound in our case are subject to a number of limitations. First, a certain response bias may occur. Patients may report a more positive result to ensure that their relationship with the physician and treatment does not change. It can be thought that patients with a good postoperative outcome are more likely to participate in a questionnaire study than patients with a negative outcome, as they are willing to do the surgeon a favor in return. On the other hand, unsatisfied patients may want to express their disappointment and may give a negative answer to every question to let the surgeon know that the operation was unsuccessful and that it has major implications on the patient’s life. In our study, the audiometric postoperative result of the nonresponders was equal to the audiometric result of the responders. However, quality of sound and possible negative feelings toward it cannot be assessed with pure-tone audiometry. Another form of response bias in our study might be that patients have different expectations of the operation. For that reason patients with great expectations might end up with slight disappointment and therefore negative answers, whereas others, who expect only “some” improvement from the operation, might give a too-positive impression. Furthermore, a certain placebo effect might be present in some patients. A third limitation of quality of life or quality of sound studies is that the used questionnaires may be inappropriate to capture the desired information and therefore may not reflect the true quality of life or sound.17 A specific limitation of this study is that a newly designed questionnaire is used because hardly any questionnaires exist to test the true quality of sound after stapedotomy. Thus it is difficult to compare our outcomes with other studies. As this is a retrospective questionnaire study, we cannot compare the postoperative quality of sound with the preoperative situation. Therefore, we are planning a prospective study in which this comparison will be possible. Furthermore the designed APOSE questionnaire will also be
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tested in patients with hearing aids as in a control group to allow for comparisons in the future. Despite the aforementioned limitations, this quality of sound study gives a good impression of the perceived sound after stapedotomy and the difference in perception between patients. It shows that an audiometric improvement does not necessarily mean an improvement in perceived sound and vice versa. But is also shows that the audiometric outcome is well related to the patient’s experienced handicap, benefit of the operation, residual difficulty, and overall satisfaction.
ACKNOWLEDGMENT We wish to thank Bert Maat for his help in collecting the audiometric results, Ingrid van Tessel for her help in collecting the questionnaires, and Robert Lindeboom for his advice concerning the statistical analysis of the data.
AUTHOR INFORMATION From the Department of Otorhinolaryngology–Head and Neck Surgery, Academic Medical Center, University of Amsterdam, The Netherlands. Corresponding author: Wilko Grolman, MD, Department of Otolaryngology, Academic Medical Center, University of Amsterdam, Postbus 22660, 1100 DD Amsterdam, The Netherlands. E-mail address: [email protected].
FINANCIAL DISCLOSURE None.
REFERENCES 1. Shea JJ, Jr. Fenestration of the oval window. Ann Otol Rhinol Laryngol 1958;67(4):932–51.
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2. Lundman L, Mendel L, Bagger-Sjoback D, et al. Hearing in patients operated unilaterally for otosclerosis: self-assessment of hearing and audiometric results. Acta Otolaryngol 1999;119(4):453– 8. 3. Morzaria S, Westerberg BD, Anzarut A. Quality of life following ear surgery measured by the 36-item Short Form Health Survey and the Glasgow Benefit Inventory. J Otolaryngol 2003;32(5):323–7. 4. Chandarana S, Parnes L, Agrawal S, et al. Quality of life following small fenestra stapedotomy. Ann Otol Rhinol Laryngol 2005;114(6): 472–7. 5. Stewart MG, Coker NJ, Jenkins HA, et al. Outcomes and quality of life in conductive hearing loss. Otolaryngol Head Neck Surg 2000;123(5): 527–32. 6. Meyer SE, Megerian CA. Patients’ perceived outcomes after stapedectomy for otosclerosis. Ear Nose Throat J 2000;79(11):846 –2, 854. 7. Ramsay H, Karkkainen J, Palva T. Success in surgery for otosclerosis: hearing improvement and other indicators. Am J Otolaryngol 1997; 18(1):23– 8. 8. Gatehouse S. A self-report outcome measure for the evaluation of hearing aid fittings and services. Health Bull (Edinb) 1999;57(6):424 – 36. 9. Marquet J. “Stapedotomy” technique and results. Am J Otol 1985; 6(1):63–7. 10. Committee on Hearing and Equilibrium guidelines for the evaluation of results of treatment of conductive hearing loss. Otolaryngol Head Neck Surg 1995;113(3):186 –7. 11. Berliner KI, Doyle KJ, Goldenberg RA. Reporting operative hearing results in stapes surgery: does choice of outcome measure make a difference? Am J Otol 1996;17(4):521– 8. 12. Zuur CL, de Bruijn AJ, Lindeboom R, et al. Retrospective analysis of early postoperative hearing results obtained after stapedotomy with implantation of a new titanium stapes prosthesis. Otol Neurotol 2003; 24(6):863–7. 13. Somers T, Govaerts P, Marquet T, et al. Statistical analysis of otosclerosis surgery performed by Jean Marquet. Ann Otol Rhinol Laryngol 1994;103(12):945–51. 14. Raske M, Welling JD, Gillum T, et al. Long-term stapedectomy results with the McGee stapes prosthesis. Laryngoscope 2001;111(11 Pt 1): 2060 –3. 15. de Bruijn AJ, Tange RA, Dreschler WA. Comparison of stapes prostheses: a retrospective analysis of individual audiometric results obtained after stapedotomy by implantation of a gold and a teflon piston. Am J Otol 1999;20(5):573– 80. 16. Gros A, Vatovec J, Zargi M, et al. Success rate in revision stapes surgery for otosclerosis. Otol Neurotol 2005;26(6):1143– 8. 17. Hunt SM, McKenna SP. Validating the SF-36. BMJ 1992;305(6854): 645.
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APPENDIX 1 THE AMSTERDAM POST OPERATIVE SOUND EVALUATION Instructions: Please choose only one response to each question PART 1 How is your hearing now compared to before the operation? □ better □ worse □ unchanged PART 2 Since the operation, how is your perception of the following sounds? High pitched sound □ good □ too loud Low pitched sound □ good □ too loud Loud sound □ good □ too loud Male voice □ good □ too loud Female voice □ good □ too loud One’s own voice □ good □ too loud Radio □ good □ too loud Television □ good □ too loud Phone conversation □ good □ too loud Music □ good □ too loud
□ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other □ too soft □ distorted □ other
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APPENDIX 2 THE OPERATION BENEFIT PROFILE (BASED ON THE GLASGOW HEARING AID BENEFIT PROFILE) Does this situation happen in your life? LISTENING TO THE TELEVISION WITH OTHER FAMILY OR FRIENDS WHEN THE VOLUME IS ADJUSTED TO SUIT OTHER PEOPLE 0 ___ No 1 ___ Yes For this situation, how In this situation, since In this situation, how How much does any satisfied are you with your the operation how much has your difficulty in this situation operation? much difficulty do you operation helped you? worry, annoy, or upset still have? you? 0___N/A 0___N/A 0___N/A 0___N/A 1___Not at all 1___No use at all 1___No difficulty 1___Not satisfied at all 2___Only a little 2___Some help 2___Only slight difficulty 2___A little satisfied 3___A moderate amount 3___Quite helpful 3___Moderate difficulty 3___Reasonably satisfied 4___Quite a lot 4___Great help 4___Great difficulty 4___Very satisfied 5___Very much indeed 5___Hearing is perfect 5___Cannot manage at 5___Delighted all Does this situation happen in NO BACKGROUND NOISE 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? HAVING A CONVERSATION WITH ONE OTHER PERSON WHEN THERE IS
Does this situation happen in 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? CARRYING ON A CONVERSATION IN A BUSY STREET OR SHOP
Does this situation happen in 0 ___ No 1 ___ Yes How much does any difficulty in this situation worry, annoy, or upset you? 0___N/A 1___Not at all 2___Only a little 3___A moderate amount 4___Quite a lot 5___Very much indeed
your life? HAVING A CONVERSATION WITH SEVERAL PEOPLE IN A GROUP
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, how much has your operation helped you? 0___N/A 1___No use at all 2___Some help 3___Quite helpful 4___Great help 5___Hearing is perfect
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
In this situation, since the operation how much difficulty do you still have? 0___N/A 1___No difficulty 2___Only slight difficulty 3___Moderate difficulty 4___Great difficulty 5___Cannot manage at all
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted
For this situation, how satisfied are you with your operation? 0___N/A 1___Not satisfied at all 2___A little satisfied 3___Reasonably satisfied 4___Very satisfied 5___Delighted