Congenital oval or round window malformations in children: Surgical findings and results in 17 cases

Bilateral Congenital Ossicular Anomalies: Are the Anomalies Symmetric for Both Ears?

OBJECTIVE

To evaluate whether bilateral congenital ossicular anomalies (COAs) differ regarding ossicular anomalies and hearing loss severities between the ears of the individual.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral academic center.

METHODS

Between March 2012 and December 2022, 7 consecutive patients (14 ears) with surgically confirmed bilateral COAs were included in the study. Preoperative pure-tone thresholds, COA classification according to the Teunissen and Cremers system, surgical procedures, and postoperative audiometric results were compared between the 2 ears of each patient.

RESULTS

The median age of the patients was 11.5 (range: 6-25) years. Both ears of each patient were categorized based on the same classification. Three patients possessed class III COAs and the other 4 had class I COAs. The interaural differences in preoperative bone and air conduction thresholds were within 15 dB for all patients. Differences in postoperative air-bone gaps between ears were not statistically significant. The surgical procedures required for ossicular reconstruction were almost identical for both ears.

CONCLUSION

The severity of ossicular abnormalities and hearing loss in patients with bilateral COAs were symmetrical between ears, thereby enabling prediction of the characteristics of the contralateral ear based on the findings observed in 1 ear. These symmetric clinical features can aid surgeons when operating on the contralateral ear.

Surgical outcome in class 4 congenital anomalies of the ossicular chain: a systematic review of the literature

OBJECTIVE

To review hearing and surgical outcomes after reconstructive middle ear surgery in class 4 congenital middle ear anomalies (CMEA), e.g., patients with oval- or round window atresia of dysplasia.

DATA SOURCES

Pubmed/Medline, Embase and Cochrane library.

REVIEW METHODS

Articles containing data on hearing outcomes and complications after reconstructive ear surgery in class 4 anomalies were analyzed and critically appraised. The following data were included and reviewed: patient demographics, audiometric testing, surgical techniques, complications, revision surgeries and their outcomes. Risk of bias was determined, and GRADE certainty of evidence was assessed. Primary outcomes were postoperative air conduction thresholds (AC), change in AC, and success rates (closure of the ABG to within 20 dB), the occurrence of complications (most importantly sensorineural hearing loss) and the long-term stability of hearing results (> 6-month follow-up) and occurrence of recurrence of preoperative hearing loss.

RESULTS

Success rates varied from 12.5 to 75% at long-term follow-up with larger cohorts reporting success rates around 50%, mean postoperative gain in AC varied from 4.7 to 30 dB and - 8.6 to 23.6 dB at, respectively, short- and long-term follow-up. No postoperative change in hearing occurred in 0-33.3% of ears, and recurrence of hearing loss occurred in 0-66.7% of ears. SNHL occurred in a total of seven ears across all studies of which three experienced complete hearing loss.

CONCLUSION

Reconstructive surgery can be an effective treatment option which should be considered in patients with very favorable baseline parameters, while also considering the substantial risk of recurrence of hearing loss, the possibility of unchanged hearing despite surgery and the rare occurrence of SNHL.

LEVEL OF EVIDENCE

2c.

Bone-conduction hearing aid is effective in congenital oval window atresia

BACKGROUND

Implantable bone-conduction hearing aids (BCHA) are effective in patients with congenital ear malformations.However, there is no large sample study to verify the efficacy of Bonebridge in patients with congenital oval window atresia.

OBJECTIVES

To investigate efficiency of implantable bone-conduction hearing aids in Mandarin-speaking patients with congenital oval window atresia.

MATERIAL AND METHODS

We retrospectively analyzed 15 patients, who were confirmed with either unilateral or bilateral congenital oval window atresia by temporal bone CT. All patients were implanted with a bone-conduction hearing device between July 2016 and July 2019 at Beijing Tongren Hospital, Capital Medical University. Pure tone audiometry (PTA), air-bone gap (ABG), speech discrimination scores (SDSs), and hearing thresholds were performed.

RESULTS

Postoperative complications including facial paralysis were particularly rare. Unaided mean sound field threshold was 62.2 ± 10.5 dBHL and that with implantable bone-conduction hearing aids was 39.1 ± 13.2 dBHL (p < 0.01). The mean speech discrimination scores improved greatly (p < 0.01), specifically with regard to sentence and disyllabic words.

CONCLUSIONS

Patients with congenital oval window atresia often show moderate to severe conductive hearing loss. Implantable bone-conduction hearing aids are considerably safe and stable for hearing rehabilitation. It is a novel treatment modality for Mandarin-speaking patients with congenital oval window atresia.

Multicenter Study of Congenital Middle Ear Anomalies. Report on 246 Ears

OBJECTIVES/HYPOTHESIS

Congenital middle ear anomalies represent a relatively rare condition. This study aimed to describe the characteristics and the surgical outcomes for patients with middle ear anomalies.

METHODS

A multicenter study was conducted of consecutive patients with congenital middle ear anomalies who underwent primary surgical treatment between January 2008 and December 2017. Demographics, surgical procedures, and audiometric data were registered into the institutional database. Hearing changes and postoperative air-bone gap (ABG) were evaluated 1 year after surgery.

RESULTS

A total of 246 patients (246 ears) (median age: 14 years, range: 4-75 years old) were included in this study. Anomalies were subdivided using the Teunissen and Cremers classification: 53 ears (22%) were categorized as class I, comprising only stapes ankylosis; 35 ears (14%) as class II, having ossicular chain anomalies with stapes ankylosis; 139 ears (57%) as class III, having ossicular chain anomalies with a mobile stapes-footplate; and 19 ears (8%) as class IV, with aplasia of the oval window. Evaluation of hearing outcomes for 198 ears with more than 1 year of follow-up revealed that good postoperative ABG (≤20 dB) was achieved in 82% of class I, 68% of class II, 74% of class III, and 23% of class IV anomalies. The postoperative ABG in class IV was significantly worse than in class I (P < .001) or class III (P < .01).

CONCLUSIONS

This study demonstrated that class III anomalies comprised the majority of middle ear anomalies and surgical outcomes for class IV anomalies are unfavorable.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2323-E2328, 2021.

[Hearing rehabilitation with the Vibrant Soundbridge in patients with congenital middle ear malformation]

BACKGROUND

Congenital aural atresia, which is usually unilateral, causes hearing loss and aesthetic impairment. Besides tympanoplasty with/without canalplasty and bone conduction devices, active middle ear implants are also available for functional rehabilitation.

OBJECTIVE

This article aims to present a contemporary review on the treatment possibilities for middle ear malformations, with a focus on audiological rehabilitation with the Vibrant Soundbridge.

MATERIALS AND METHODS

A selective literature search for treatment possibilities was performed in PubMed up to October 2020, and personal clinical experiences are reported.

RESULTS

The Vibrant Soundbridge, which is approved for children ≥ 5 years, is suitable for treatment of middle ear malformations with a Jahrsdoerfer score ≥ 5. Although implantation of a Vibrant Soundbridge is surgically more demanding than implantation of a bone conduction device, the method is safe, delivers good auditory results (superior to bone conduction devices in terms of speech understanding and spatial hearing), does not involve intensive postsurgical care, and rarely requires revision surgery. The Vibrant Soundbridge can be coupled to (remnants of) the ossicular chain or the round window.

CONCLUSION

The Vibrant Soundbridge is an appropriate treatment method in patients with middle ear malformations who have suitable anatomical preconditions.

Bilateral Oval and Round Window Atresia on CT Temporal Bone: A Rare Anomaly Clinically Mimicking Otosclerosis in an Adult

We present a rare adult case of bilateral oval and round window atresia. Clinical and audiologic findings were suggestive of otosclerosis. High resolution CT Temporal bones showed unequivocal findings of bilateral oval and round window atresia. Atresia of these windows is a rare temporal bone anomaly. Presentation as an adult can confound the clinicians and warranting a closer look on the CT for atretic windows and subtle signs of otosclerosis in patients with conductive hearing loss.

Surgical Management for Dysplastic or Congenitally Absent Oval Window

OBJECTIVE

To evaluate surgical findings and hearing results for patient's undergoing the described surgical approach for congenitally absent or dysplastic oval window (OW).

STUDY DESIGN

The Institutional Review Board approved retrospective review of patients with conductive hearing loss (CHL) operated on from 1992 to 2016.

SETTING

Academic tertiary center.

PATIENTS

Patients with CHL, an intact tympanic membrane (TM), and without history of chronic infection underwent middle ear exploration. Eleven patients and 13 ears underwent an oval window drill-out (OWD) procedure.

INTERVENTION

Eleven patients presented, all with dysplastic or congenitally absent oval window (CAOW). CHL was identified using audiometry and tuning forks, many patients also had preoperative computed tomography temporal bones. A transcanal approach was used and an OWD was performed with a variety of prostheses placed.

MAIN OUTCOME MEASURE

Audiometric studies before and after intervention were compared with 12 month and long-term follow-up (1-22 yr).

RESULTS

Preoperative air-bone gaps ranged from 40 to 60 dB and averaged 55.1 dB. Postoperative air-bone gaps ranged from 0 to 60 dB and averaged 24.1 dB. The preoperative pure-tone average (PTA) ranged from 55 to 99 dB and averaged 71.3 dB. Postoperative PTA ranged from 21 to 108 dB and averaged 49.6 dB.

CONCLUSION

Dysplastic and CAOW are uncommon congenital major ear anomalies. OWD is a viable treatment option, though careful counseling is critical, as significant complications are possible, especially with facial nerve (FN) abnormalities. This series demonstrates successful closure of the air-bone gap for many patients with this technique.

Effect of Oval Window Blockage on Bone Conduction in Cadaver Heads

OBJECTIVE

This study aimed to explore the feasibility of medical adhesive in the molding of oval window (OW) blockage in cadaver heads and to study the effect on bone conduction (BC).

METHODS

Four cadaver heads were selected to establish OW blockage model. The daub type of medical adhesive was used to immobilize OW. The vibration properties of the round window membrane (VRWM) in response to the acoustic stimulation, and the vibration properties of the round window membrane and cochlear promontory (VCP) in response to the BC transducer B-71 stimulation were assessed by laser Doppler vibrometer in both pre-OW blockage and post-OW blockage.

RESULTS

After blocking the oval window, the mean values of the sound-induced velocities amplitude responses of the round window membrane by air conduction were decreased significantly beyond 30 dB in all measured frequencies (p < 0.05). The round window membrane relative velocity (VRWM/VCP) shows a decrease of about 1 dB at 1 and 3 kHz frequencies and a slight increase of around 0.5 dB from 4 to 8 kHz frequencies in post-OW blockage. However, it should also be noted that the VRWM/VCP is a significant decrease of 1.2 dB at 3 kHz in post-OW blockage compared with pre-OW blockage (p < 0.05).

CONCLUSION

Medical adhesive was available for the immobilization of oval window. In cadaver heads, the effect of OW blockage on the BC was the notching at 3 kHz.

CT Imaging Categorization and Biomarker Study of Anomalous Tympanic Segment of the Facial Nerves in Patients With Hearing Loss in the Absence of Microtia

The purpose of this study is to categorize anomalous tympanic facial nerve (FN) on high-resolution computed tomography (HRCT) and to determinate the significance of associated temporal bone anomalies and congenital syndromes without microtia in patients with hearing loss. A retrospective analysis of HRCT findings in 30 temporal bones in 18 patients with anomalous FN was performed. Abnormalities of the tympanic FN were categorized as follows: category 1: FN medially positioned, but above the oval window; category 2: FN in the oval window niche; and category 3: FN below the oval window. Potential associated findings that were assessed included stapes abnormalities, oval window atresia, and inner ear anomalies, as well as the presence of a known congenital syndrome with hearing loss. The most common type of anomalous tympanic FN was category 1 (67%, n = 20), following by group 2 (20%, n = 6) and group 3 (13%, n = 4). Stapes anomalies were detected in 77% of temporal bones (n = 23), oval window atresia was detected in 43% of temporal bones (n = 13), and inner ear anomalies were detected in 70% of temporal bones (n = 21). Anomalous tympanic facial nerves in temporal bone with conductive hearing loss were often (60%) not associated with oval window atresia. The combination of aberrant tympanic FN and inner ear anomalies was significantly (P = .038) associated with a known congenital syndrome (6 patients), including CHARGE syndrome, oculo-auriculo-vertebral spectrum, Pierre-Robin sequences, and Down syndrome. Therefore, an anomalous tympanic FN in conjunction with inner ear anomalies appears to be a biomarker for certain congenital syndromes with hearing loss in the absence of microtia.

Bone conduction hearing in the blockage of oval and/or round windows in cats

BACKGROUND

Simple or non-syndromic types of oval window (OW) or round window (RW) atresia are relatively rare in clinical. Few studies have assessed bone conduction (BC) hearing in OW or RW atresia patients, with some reporting that BC hearing lies within the normal range, whereas others observing impaired BC hearing.

AIMS/OBJECTIVES

This study explored the effect of blocking the OW and RW during BC in cat models.

MATERIAL AND METHODS

Twenty-four cats were randomly divided into three immobilization groups (OW blockage, RW blockage, and OW + RW blockage) and control group. Each immobilization group also had the initial control state before blockage. Medical adhesive and ear mould glue were used to immobilise the stapes footplate and RW, respectively. Comparisons were made of the auditory brainstem response (ABR) thresholds before and after immobilization for the three immobilization groups during three different stimuli [air conduction (AC) click, BC click, and BC pure tones].

RESULTS

The AC click thresholds increased after immobilisation in three experimental groups compared to the control group (p < .05). The AC click thresholds increased compared to their initial control state after all three immobilization groups (p < .05). With an increase in frequency from 2 to 8 kHz, there was a general decrease in the difference between pre- and post-immobilization BC hearing thresholds in all three immobilization groups. The BC click threshold and BC tone thresholds at 2-4 kHz in both OW blockage and OW + RW blockage groups exceeded those in RW blockage group (p < .05).

CONCLUSIONS AND SIGNIFICANCE

The use of medical adhesive and ear mould glue for the blockages of OW and RW, respectively in cats was feasible. The effect of blocking the OW and RW in BC hearing was larger at low frequencies than high frequencies between 2 and 8 kHz. OW blockage had a greater effect than RW blockage on BC hearing at 2-4 kHz range.

Reporting and Description for Congenital Middle Ear Malformations to Facilitate Surgical Management

Introduction:

The aim of this work was to report and describe the different types of congenital middle ear malformations in order to guide surgical treatment approaches and improve outcomes for affected patients.

Methods:

The authors reviewed patients with congenital middle ear malformations who received surgical treatment between September 2010 and March 2017. Patient characteristics, middle ear deformities, and surgical procedures were documented.

Results:

In this retrospective study, 35 patients were reviewed. A description of middle ear malformation was proposed that considers ear embryogenesis and focuses on stapes deformity, with the main purpose of facilitating surgical approach selection to reconstruct the ossicular chain. Patients were classified into 3 categories: type I (19 cases), mobile stapes footplate, which included type Ia with normal stapes suprastructure and type Ib with abnormal stapes suprastructure; type II (4 cases), fixed stapes footplate, which included type IIa with normal ossicular chain and type IIb with abnormal ossicular chain; and type III (12 cases), oval window bony atresia or aplasia, with or without round window atresia. Types II and III could have concomitant aberrant facial nerve. Different surgical approaches are described.

Conclusions:

The authors describe the different types of congenital middle ear malformations. This category description considers ear embryogenesis and is focused on stapes deformity. It may provide better understanding of disease development and guide modern hearing reconstructive surgery.

Middle ear abnormalities in Van Maldergem syndrome

Van Maldergem syndrome (VMS) is a very rare syndrome that was first described in 1992. The main features of this syndrome comprise intellectual disability, blepharo-naso-facial malformation, and hand anomalies. Almost all nine described patients have been shown to be affected by conductive hearing impairment attributed to microtia, and atresia of the outer ear canal. Here, we present a VMS patient with congenital malformations of the middle ear as the main reason for severe conductive bilateral hearing impairment. To our knowledge, this is the first report to describe middle ear abnormalities in VMS. These malformations were seen on high resolution Computed Tomography scanning and during an exploratory tympanotomy. Due to the severity of the middle ear abnormalities and the risk for facial nerve damage, the patient was not offered an ossicular chain reconstruction but a bone conduction device after this exploratory tympanotomy. © 2016 Wiley Periodicals, Inc.