International Journal of Pediatric Otorhinolaryngology 78 (2014) 55–59

The surgical results of stapes fixation in children

Yun Suk An, Kwang-Sun Lee *

Department of Otolaryngology, Asan Medical Center, University of Ulsan College of Medicine, South Korea

A R T I C L E I N F O

Article history:

Received 20 June 2013

Received in revised form 23 October 2013

Accepted 29 October 2013

Available online 7 November 2013

Keywords:

Stapedotomy

Children

Congenital stapes fixation

Juvenile otosclerosis

Ossicular anomaly

A B S T R A C T

Objectives: The aims of this study were to review the causes of stapes fixation in children undergoing

stapes surgery and to analyze the results of stapes surgery in children in the short term, at 1 year, and

over the long term.

Methods: The medical records of 18 children (28 ears) who had undergone stapes surgery between

January 1999 and December 2012 were retrospectively reviewed. The medical history, computed

tomography results, intraoperative findings, video clips, and hearing outcomes of all patients were

reported.

Results: The mean age of patients was 11.1 years (range, 5.9–15.3 years). Congenital stapes fixation (22/

28 ears, 79%) and juvenile otosclerosis (6/28 ears, 21%) were responsible for all cases of stapes fixation.

Intraoperatively, abnormal facial nerves that were downwardly displaced over the stapes footplate were

noted in four ears. Incudostapedotomy was performed in 24 ears, malleostapedotomy in three, and

partial stapedectomy in one. The early postoperative audiometric outcome was favorable in 21 ears

(87.5%). There was no significant difference between early postoperative (87.5%), 1 year postoperative

(91%), and long term (92.3%) favorable audiometric results. There was no significant difference in the

postoperative hearing results between patients with congenital stapes fixation and juvenile otosclerosis.

Conclusion: Congenital stapes fixation was diagnosed in 22 (79%) ears and juvenile otosclerosis in six

(21%) ears from a series of 28 ears that were operated on for stapes fixation. Facial nerve anomalies

were found in four of 22 ears (18%) that had congenital stapes fixation. There was no difference in the

postoperative hearing results between patients with congenital stapes fixation and juvenile

otosclerosis. Regardless of the cause of stapes fixation, stapedotomy is a safe and effective procedure

for managing the condition.

� 2013 Elsevier Ireland Ltd. All rights reserved.

Contents lists available at ScienceDirect

International Journal of Pediatric Otorhinolaryngology

jo ur n al ho m ep ag e: ww w.els evier . c om / lo cat e/ i jp o r l

1. Introduction

Stapes surgery for correction of conductive hearing loss is awell-established procedure in adults. However, stapes surgery inchildren is less commonly reported, primarily because of the risk ofpostoperative sensorineural hearing loss (SNHL). Due to this risk,most otologists operate on children who are old enough toparticipate in the decision-making process. Also, hearing aids are aviable alternative to stapes surgery and offer good prospects forrehabilitation following conductive or mixed hearing loss due tostapes fixation. Thus, stapes surgery in the pediatric populationremains controversial despite improvements in surgical technique.

Since the first case series was published by House et al. [1] in1980, there have been few reports on stapes surgery in childrenunder the age of 18. In these reports, the major causes of stapes

* Corresponding author at: Department of Otolaryngology, Asan Medical Center,

University of Ulsan College of Medicine, 86 Asanbyeongwon-gil, Songpa-gu, Seoul

138-736, South Korea. Tel.: +82 2 3010 3711; fax: +82 2 489 2773.

E-mail address: kslee2@amc.seoul.kr (K.-S. Lee).

0165-5876/$ – see front matter � 2013 Elsevier Ireland Ltd. All rights reserved.

http://dx.doi.org/10.1016/j.ijporl.2013.10.043

fixation were congenital stapes fixation and otosclerosis, whichhad a similar prevalence. However, in our experience with Koreanpatients, juvenile otosclerosis was rare compared with congenitalstapes fixation. The aims of this study were to determine theincidence of congenital stapes fixation and otosclerosis in childrenwho had undergone surgery for stapes fixation and to analyze thepostoperative audiologic results in the short term, at 1 year, andover the long term.

2. Materials and methods

The medical records of 18 pediatric patients (28 ears) whounderwent stapes surgery for conductive hearing loss betweenJanuary 1999 and December 2012 were retrospectively reviewed.All patients were younger than 15 years and underwent stapessurgery by one surgeon at the Asan Medical Center (Seoul, SouthKorea).

This retrospective study was approved by the InstitutionalReview Board of Asan Medical Center and for data collection andanalysis, and informed consent was waived. There were nine males(13 ears) and nine females (15 ears). The mean age at the time of

Fig. 1. Axial CT scan demonstrating osteolytic foci (arrow) of juvenile otosclerosis.

Y.S. An, K.-S. Lee / International Journal of Pediatric Otorhinolaryngology 78 (2014) 55–5956

surgery was 11.1 years (SD, 3.2; age range, 5.9–15.3 years). Therewere 16 right-sided ears and 12 left-sided; 10 from 18 childrenunderwent bilateral surgery.

All patients had undergone a preoperative workup comprising ofa clinical examination, audiometric data collection, and high-resolution temporal bone computed tomography (HR TBCT). Ageat surgery, age at onset, bilaterality, sex, and intraoperative findingwere analyzed using operation records and video clips. Postoperativecomplications and hearing results were compared for various clinicalparameters. Revision surgeries were excluded from this study.

The diagnosis of juvenile otosclerosis was made based on thepresence of progressive deafness associated with a typicalotosclerosis focus in the HR TBCT (Fig. 1). A positive familyhistory, and/or exclusion of other causes of progressive conductivehearing loss were considered. The presence of malformed ossicleswas determined on the basis of surgical findings and HR TBCT.

Surgical methods. All patients underwent general anesthesia. Anendo-meatal approach with ear canal speculum was used in allcases. After elevation of the tympanomeatal flap, the chordatympani nerve was slightly detached from the bony annulusanteriorly, and bone over the incudostapedial joint (ISJ) wasremoved with a small osteotome with mallet. After exposure ofthe ISJ, the shape and mobility of the ossicular chain was observed.When stapes fixation was identified, the stapes tendon was cutfollowed by separation of the ISJ. The posterior crura were cut withcururotome scissors, the anterior crus with capitulum of stapes wasdown fractured with a fine pick, and then the stapes superstructurewas removed. An approximately 0.6 mm fenestrum was made in thestapes footplate using a 0.5 mm Skeeter drill. Routinely, a Fish typepolytetrafluoroethylene (Teflon1) piston-wire prosthesis wasattached in the long process of the incus. When an anomalousincus long process or incus fixation was found, the prosthesis wasattached to the handle of malleus (malleostapedotomy).

Audiometric evaluation. Preoperative audiometric data werecompared to early postoperative (less than 4 months), approxi-mate 1 year postoperative, and last follow-up (more than 18months) data. Preoperative and postoperative air conduction (AC)and bone conduction (BC) tests at 0.5, 1, 2, and 3 kHz were includedin the analysis. When a frequency of 3 kHz was not used, the meanvalue of the 2 and 4 kHz results was substituted.

Table 1Preoperative and postoperative audiometric outcomes for 18 children (28 ears) who u

Period No. of ears Mean (SD) [range]

AC (dB)

Preoperative 28 51.8 (9.4) [30–65]

Early postop 24 23.5 (7.7) [13.7–38.8]

1 year 22 23.1 (5.3) [12.5–32.5]

Last 13 24.9 (16.4) [10.0–76.3]

ABG, air-bone gap; BC, bone conduction; AC, air conduction; early postop, postoperativ

postoperative results more than 18 months.

The air-bone gap (ABG) was calculated only for those patientswho had BC and AC values collected at the same time. The patient’shearing level in the postoperative period was classified into fourgroups: (1) very good, ABG less than 10 dB; (2) good, ABG between10 and 20 dB; (3) acceptable, ABG between 20 and 30 dB; and (4)bad, ABG over 30 dB.

The mean preoperative AC was 51.8 dB (SD, 9.4; range, 30–65 dB), and the mean preoperative ABG was 35.3 dB (SD, 10.3;range 9.5–55 dB; Table 1).

Statistical data analysis. Categorical data were expressed aspercentages and continuous variables were expressed as meanswith standard deviations (SDs). The Fisher exact test was used tocompare categorical data. Paired t-tests were used for changes inhearing within a group, and independent t-tests for the compari-son of hearing between groups. A p value of less than 0.05 was thecriterion for statistical significance. Statistical analyses wereperformed using SPSS software (version 21).

3. Results

3.1. Surgical findings

Congenital stapes fixation was found in 15 patients (22 ears)and juvenile osclerosis in 3 patients (6 ears). Two girls (four ears)and one boy (two ears) had juvenile bilateral otosclerosis.Interestingly, two girls with juvenile otosclerosis were identicaltwins.

Congenital stapes fixation with an anomaly of the ossicularchain was found in 10 of 22 ears. Among them, stapessuprastructure anomalies were found in five ears, a fibrous bandof ISJ (Fig. 2) in three ears, ISJ fusion in one ear, and a stapessuprastructure anomaly with incus fixation in one ear. Fourpatients had an anomalous facial nerve course with the tympanicsegment located inferior to the oval window niche (Fig. 3).

Incudostapedotomy was performed in 24 ears, malleostape-dotomy in three, and partial stapedectomy in one due to incidentalfootplate fracture.

3.2. Postoperative audiometric results: early, 1 year,

and last follow-up

Early postoperative (2.1 � 1.2 months) audiometric data wereavailable for 24 ears. The mean early postoperative AC was 23.5 dB(SD, 7.7; range 13.7–38.8 dB) and the mean residual ABG was 11.6 dB(SD, 7.4; range 0–27.5 dB).

The early postoperative audiometric outcome was classified asvery good in 13 ears (54.2%), good in eight (33.3%), and acceptablein three (12.5%). There were no cases of bad outcomes.

At 1 year after surgery (22 ears), the mean AC was 23.1 dB (SD,5.3; range 12.5–32.5 dB) and the mean residual ABG was 11.3 dB(SD, 6.5; range 0.50–29.3 dB). The mean AC was 24.6 dB (SD, 11.9;range 10.0–76.3 dB) and the mean residual ABG was 11.5 dB (SD,8.5; range 0.5–45.0 dB). The audiometric outcome at 1 year wasclassified as very good or good in 20 ears (91%), which was not

nderwent stapes surgery.

BC (dB) ABG (dB)

16.5 (7.8) [3–31] 35.3 (10.3) [9.5–55.0]

11.9 (4.0) [5.0–21.3] 11.6 (7.4) [0–27.5]

11.8 (4.3) [3–22] 11.3 (6.5) [0.5–29.3]

13.4 (6.3) [7.5–31.3] 11.5 (11.1) [2–45.0]

e results less than 4 months; 1 year, postoperative results 1 year � 3 months; last,

Fig. 2. Intraoperative finding of a fibrous band (black arrow) in the incudostapedial

joint; asterisk, chorda tympani nerve.

Fig. 3. Intraoperative findings of an anomalous facial nerve (arrows). The tympanic

segment of facial nerve was downwardly displaced over the atretic oval window

(A). Coronal CT scan demonstrating anterior inferior location of facial nerve (arrow)

(B).

Fig. 4. The audiometric outcomes in the preoperative and postoperative periods.

‘‘Very good’’ was defined as an air-bone gap (ABG) � 10 dB; ‘‘Good’’ was defined as

an ABG of 11–20 dB; ‘‘Acceptable’’ was defined as an ABG of 21–30 dB; and ‘‘Bad’’

was defined as ABG higher than 30 dB.

Y.S. An, K.-S. Lee / International Journal of Pediatric Otorhinolaryngology 78 (2014) 55–59 57

significantly different from the early postoperative results (87.7%classified as very good or good).

The mean duration to last follow-up in 13 ears was 46.8 � 23.5months. The mean last follow-up ABG was 11.5 dB (range, 2.0–45.0 dB). From 13 ears, nine (69.2%) had a very good and three (2%)had a good result. One case of postoperative SNHL, a loss of 21.25 dBcompared with the preoperative mean BC value, was found at long-term follow-up audiometry (Table 1, Fig. 4).

There was no significant difference in either preoperative orpostoperative ABG between incudostapedeotomy and malleosta-pedotomy.

3.3. Comparison hearing results between congenital stapes fixation

and juvenile otosclerosis

There was no significant difference in either the preoperative and1 year postoperative BC and ABG values or the last postoperativefollow-up AC, BC, and ABG values between congenital stapes fixationand juvenile otosclerosis. However, there was a significantdifference in both preoperative and early postoperative BC valuesbetween congenital stapes fixation and juvenile otosclerosis(p = 0.035 and 0.041, respectively; Table 2).

In early postoperative audiometric outcomes, six of 18 ears(44.4%) with congenital stapes fixation had a very good result and15 ears (83.3%) had either a very good or good result, whereas fourof six ears (66.7%) with juvenile otosclerosis had a very good resultand six ears (100%) had either a very good or good result. ABGclosure after stapedotomy was more likely in juvenile otosclerosisthan in congenital stapes fixation, but the finding was notsignificant (p = 0.546; Fig. 5).

Table 2Comparison of hearing results between congenital stapes fixation and juvenile otoscle

Congenital stapes fixation

No. of ears Hearing (dB)

Preoperative BC 22 14.9 � 7.9

Preoperative AC 22 50.9 � 9.8

Preoperative ABG 22 36.0 � 10.9

Early postop BC 18 11.0 � 3.8

Early postop AC 18 23.5 � 7.6

Early postop ABG 18 12.5 � 7.7

1 year postop BC 16 11.5 � 4.4

1 year postop AC 16 24.0 � 5.5

1 year postop ABG 16 12.5 � 7.1

Last follow-up postop BC 9 13.7 � 7.1

Last follow-up postop AC 9 28.3 � 18.8

Last follow-up postop ABG 9 14.6 � 4.6

ABG, air-bone gap; BC, bone conduction; AC, air conduction; early postop, postoperativ

follow-up, postoperative results more than 18 months.* p < 0.05.

3.4. Comparison of hearing results between congenital isolated stapes

fixation and congenital stapes fixation with ossicular anomaly

There was no significant difference in either the preoperativeABG or BC values between stapes fixation with ossicular anomalyand isolated stapes fixation. However, there was a significantdifference in preoperative AC values between stapes fixation withossicular anomaly and isolated stapes fixation (p = 0.001).

There was no statistical difference in the early postoperative, 1year postoperative, and last postoperative follow-up AC, BC, andABG values between stapes fixation with ossicular anomaly andisolated stapes fixation (Table 3).

rosis.

Juvenile otosclerosis p value

No. of ears Hearing (dB)

6 22.4 � 3.9 0.035*

6 55.2 � 7.5 0.330

6 32.8 � 8.4 0.515

6 14.9 � 3.6 0.041*

6 23.5 � 9.0 0.999

6 8.7 � 6.0 0.277

6 12.7 � 4.2 0.570

6 20.8 � 4.6 0.226

6 8.2 � 3.6 0.169

4 12.6 � 4.9 0.786

4 17.2 � 4.8 0.277

4 4.6 � 3.3 0.136

e results less than 4 months; 1 year, postoperative results 1 year � 3 months; last

Fig. 5. Postoperative audiometric outcomes (air-bone gap) for pediatric

stapedotomy for congenital stapes fixation and juvenile otosclerosis.

Fig. 6. Postoperative audiometric outcomes (air-bone gap) for pediatric

stapedotomy for isolated stapes fixation and stapes fixation with ossicular anomaly.

Y.S. An, K.-S. Lee / International Journal of Pediatric Otorhinolaryngology 78 (2014) 55–5958

In early postoperative audiometric outcomes, five of eight ears(62.5%) with congenital isolated stapes fixation had a very goodresult and six ears (75.0%) had a very good or good result whereasfour of 10 ears (40.0%) with congenital stapes fixation withossicular anomaly had a very good result and nine ears (90.0%) hada very good or good result. ABG closure to within 10 dB afterstapedotomy was more likely in congenital isolated stapes fixationthan in congenital stapes fixation with ossicular anomaly but thefinding was not significant (p = 0.319; Fig. 6).

4. Discussion

Although there are many reports of the surgical outcomes ofstapes surgery in adults, reports of the results of this surgery inchildren are rare. Preadolescents are usually strongly motivated toundergo surgery between the ages of 10 and 12 years and stapessurgery is uncommon under this age. However, recent studies [1–6]demonstrate that there is good potential to achieve satisfactoryhearing improvements in children undergoing stapes surgery.

Otosclerosis is one of the most common causes of adult-onsethearing loss in the Caucasian population, with a prevalence of 0.3–0.4% [7]. The incidence of otosclerosis is different between ethnicgroups. Otosclerosis incidence is high in Caucasians, but low in EastAsians, people of African descent, and Native Americans. Recentlythe incidence of otosclerosis seems to be increasing amongstJapanese people. Ohtani reported that the incidence of histologicotosclerosis among Japanese people seemed to be similar to thatamong Caucasians [8].

In 2012, at the Asan Medical Center, otological surgeries wereperformed on 1157 ears. Among these ears, tympanomastoid

Table 3Comparison of hearing results due to existence of concomitant ossicular anomalies.

Congenital isolated stapes fixation

No. of ears Hearing (dB

Preop BC 12 12.2 � 8.8

Preop AC 12 45.3 � 9.4

Preop ABG 12 33.1 � 12.0

Early postop BC 8 9.7 � 3.8

Early postop AC 8 20.8 � 8.3

Early postop ABG (dB) 8 11.1 � 10.1

1 yr postop BC 10 11.2 � 5.3

1 yr postop AC 10 22.6 � 5.2

1 yr postop ABG 10 11.4 � 8.1

Last follow-up postop BC 6 14.0 � 8.6

Last follow-up postop AC 6 30.2 � 23.0

Last follow-up postop ABG (dB) 6 16.2 � 14.7

ABG, air-bone gap; BC, bone conduction; AC, air conduction; early postop, postoperativ

postoperative results more than 18 months.* p < 0.05.

surgeries were performed on 643 ears compared to stapessurgeries on 36 ears. Compared to the incidence of chronic otitismedia, stapes fixation had a relative incidence of 5.6%. In ourstudy, 121 patients (175 ears) underwent stapes surgery forconductive hearing loss with normal tympanic membrane from1999 to 2012. Among 175 ears, only 28 ears (19.4%) wereassociated with patients less than 15 years old.

In the 1980 pediatric stapedectomy series of House et al. [1],congenital stapes fixation was noted in 20 of 34 ears (58.8%) andjuvenile otosclerosis in 14 (41.2%). In 2010, Denoyelle et al. [2]reported that congenital stapes fixation was diagnosed in 25 of35 ears (71%) and juvenile otosclerosis in six of 35. In 2013,Carlson et al. [6] reported that congenital stapes fixation wasdiagnosed in 27 of 44 ears (61.4%) and juvenile otosclerosis in17. We found that congenital stapes fixation occurred in 22 of 28ears (79%) and juvenile osclerosis in six (21%).

Denoyelle et al. [2] reported that 94% of the results of 35stapedectomies in children were considered good or very good.They noted no significant differences between early postoperative,1 year postoperative, and last follow-up audiometric results.

We found that 87.5% of ears at the early postoperative period,91% at 1 year after surgery, and 92.3% at last follow-up showed animprovement in hearing of less than 20 dB in ABG. The ABG did notwiden significantly over time; however, one ear had a poor resultin long-term follow-up necessitating revision surgery and incusfixation due to new bone formation, which was confirmed inrevision explorative tympanotomy.

Stapedotomy in children has been performed for correction ofconductive hearing loss caused by congenital stapedial fixation orjuvenile otosclerosis. Most studies report that juvenile otosclero-sis is associated with more favorable audiometric outcomes than

Congenital stapes fixation with ossicular anomaly p value

) No. of ears Hearing (dB)

10 18.2 � 5.5 0.075

10 57.6 � 4.9 0.001*

10 39.5 � 8.7 0.182

10 12.1 � 3.6 0.177

10 26.8 � 6.5 0.173

10 12.4 � 3.7 0.736

6 11.9 � 2.6 0.762

6 26.3 � 5.7 0.211

6 14.3 � 4.7 0.443

3 13.1 � 3.9 0.450

3 24.6 � 7.5 0.756

3 11.5 � 4.1 0.938

e results less than 4 months; 1 year, postoperative results 1 year � 3 months; last,

Y.S. An, K.-S. Lee / International Journal of Pediatric Otorhinolaryngology 78 (2014) 55–59 59

congenital stapedial fixation. House et al. [1] found that 77% (10/14) of ears had successful ABG closure (<10 dB ABG) afterstapedectomy in congenital stapedial fixation but 92% (22/24) ofears had successful ABG closure in juvenile otosclerosis. De la Cruzet al. [4] also reported better hearing results following stapedec-tomy in children with otosclerosis than with congenital fixation.However, recently Nelian [9] reported the postoperative ABG inthe congenital stapes fixation group was similar to juvenileotosclerosis.

We found that 44.4% (8/18) of ears had successful ABG closure(<10 dB ABG) after stapedectomy for congenital stapedial fixationbut 66.7% (4/6) of ears had successful ABG closure in juvenileotosclerosis. Thus, stapedotomies for juvenile otosclerosis mayproduce better hearing results than for congenital stapedial fixation.

We hypothesized that the surgical outcomes of isolated stapesfixation would be superior to those of stapes fixation withconcomitant ossicular chain anomaly. Thomeer et al. [5], reportingon 30 cases of stapedectomy for congenital stapes fixation withconcomitant ossicular chain anomaly, found that an ABG closure of20 dB or less was achieved in 21 of 30 ears (70%); however, theyincluded both adults and children.

We found that 62.5% (5/8) of ears had successful ABG closure(<10 dB ABG) after stapedectomy in ears with congenital isolatedstapes fixation but 40.0% (4/10) of ears had successful ABG closurein congenital stapes fixation with ossicular anomaly; however, theresult was not significant.

The appropriate age at which stapedectomy should be performedin children has not been established. There are no reports of childrenyounger than 5 years undergoing the procedure. Historically, themain opposition to pediatric stapedectomy has been due to concernsover stapes gusher and ensuing SNHL. Although the hearing resultsof stapes surgery in children may deteriorate over time, we foundthat children who underwent stapes surgeries did not show anincreased ABG over time.

5. Conclusions

Congenital stapes fixation was diagnosed in 22 (79%) ears andjuvenile otosclerosis in six (21%) ears from a series of 28 ears that

were operated on for stapes fixation. Facial nerve anomalies werefound in four of 22 ears (18%) that had congenital stapes fixation.There was no difference in postoperative hearing results betweenpatients with congenital stapes fixation and juvenile otosclerosis,regardless of the cause of stapes fixation, and stapedotomy is safeand effective in managing the condition. Concomitant ossicularanomaly should not necessarily be viewed as a contraindication forstapedotomy. The early-, mid-, and long-term postoperativeaudiometric outcomes were favorable in this series.

Conflict of interest

The authors have no financial disclosure or conflicts of interest.

Financial disclosure

None.

References

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[9] R.E. Nelian, R.W. Zhang, P.S. Roland, B. Issacson, K.H. Lee, J. Walter Kutz Jr., Pediatricstapedectomy: does cause of fixation affect outcomes? Int. J. Pediatr. Otorhinolar-yngol. 77 (July (7)) (2013).