Congenital Aural Stenosis: Clinical Features and Long-term Outcomes

Biomedical application of materials for external auditory canal: History, challenges, and clinical prospects

Biomaterials play an integral role in treatment of external auditory canal (EAC) diseases. Regarding the special anatomic structure and physiological characteristics of EAC, careful selection of applicable biomaterials was essential step towards effective management of EAC conditions. The bioactive materials can provide reasonable biocompatibility, reduce risk of host pro-inflammatory response and immune rejection, and promote the healing process. In therapeutic procedure, biomaterials were employed for covering or packing the wound, protection of the damaged tissue, and maintaining of normal structures and functions of the EAC. Therefore, understanding and application of biomaterials was key to obtaining great rehabilitation in therapy of EAC diseases. In clinical practice, biomaterials were recognized as an important part in the treatment of different EAC diseases. The choice of biomaterials was distinct according to the requirements of various diseases. As a result, awareness of property regarding different biomaterials was fundamental for appropriate selection of therapeutic substances in different EAC diseases. In this review, we firstly introduced the characteristics of EAC structures and physiology, and EAC pathologies were summarized secondarily. From the viewpoint of biomaterials, the different materials applied to individual diseases were outlined in categories. Besides, the underlying future of therapeutic EAC biomaterials was discussed.

Implantable hearing devices in clinical practice. Systematic review and consensus statements

Objective

Implantable hearing devices represent a modern and innovative solution for hearing restoration. Over the years, these high-tech devices have increasingly evolved but their use in clinical practice is not universally agreed in the scientific literature. Congresses, meetings, conferences, and consensus statements to achieve international agreement have been made. This work follows this line and aims to answer unsolved questions regarding examinations, selection criteria and surgery for implantable hearing devices.

Materials and methods

A Consensus Working Group was established by the Italian Society of Otorhinolaryngology. A method group performed a systematic review for each single question to identify the current best evidence on the topic and to guide a multidisciplinary panel in developing the statements.

Results

Twenty-nine consensus statements were approved by the Italian Society of Otorhinolaryngology. These were associated with 4 key area subtopics regarding pre-operative tests, otological, audiological and surgical indications.

Conclusions

This consensus can be considered a further step forward to establish realistic guidelines on the debated topic of implantable hearing devices.

Diagnosis and treatment of congenital stenosis of external auditory canal with external auditory canal cholesteatoma complicated with exudative effusion in the middle ear and mastoid process

BACKGROUND

The optimal timing for surgery to promote postoperative recovery in children with congenital stenosis of the external auditory canal with external auditory canal cholesteatoma, who are susceptible to exudative inflammation of middle ear and mastoid process, is still uncertain.

OBJECTIVES

To investigate the treatment of congenital stenosis of external auditory canal with external auditory canal cholesteatoma complicated with exudative inflammation.

MATERIAL AND METHODS

A retrospective analysis of 45 patients with congenital stenosis of external auditory canal with external auditory canal cholesteatoma complicated with mastoiditis. Based on whether effusion had resolved at the time of surgery, the patients were divided into two groups. Pure-tone audiometry tests were performed before and after surgery for both groups.

RESULTS

The average postoperative duration of dry ear was 36.38 days in Group 1 and 47.90 days in Group 2 (p < 0.05). Among patients who underwent hearing reconstruction, the average air conduction threshold decreased by 15-36 dBHL in Group 1 and by 7-22 dBHL in Group 2 (p < 0.05).

CONCLUSIONS AND SIGNIFICANCE

The postoperative outcomes of dry ear and hearing improvement can be enhanced by performing operation after effusion resolution in cases of congenital external auditory canal stenosis with external auditory canal cholesteatoma exudative inflammation.

Pediatric cholesteatoma associated with congenital aural atresia and stenosis

OBJECTIVE

Investigate presenting features, associated surgical treatment, and outcomes in patients with cholesteatoma associated with congenital aural atresia (CAA) or stenosis (CAS).

METHODS

Colorado Multiple Institution Review Board approval was obtained. A retrospective chart review was performed at a single tertiary care children's hospital of all pediatric patients with congenital aural atresia or stenosis with associated cholesteatoma from January 1, 2003, to October 15, 2018.

RESULTS

Of the 278 patients identified with CAA or CAS, twelve (4.3 %) were found to have a canal cholesteatoma. There was a male predominance (8:4). Nine patients (75 %) had conductive loss and three (25 %) had mixed loss. Four patients (33.3 %) exhibited canal cholesteatomas extending into the middle ear or mastoid cavity. All patients underwent surgery, and 25 % of patients required revision canalplasty while 58 % of patients required revision surgery for cholesteatoma recidivism. The average age at the time of surgery was 11.3 ± 3.7 years.

CONCLUSION

Fewer than 5 % of pediatric patients with congenital aural atresia or stenosis were diagnosed with an acquired canal cholesteatoma. The need for revision surgery was common, occurring in >50 % of cases. Screening patients with CAA/CAS for cholesteatoma with imaging is recommended to avoid the morbidity of delayed identification.

Cholesteatoma in Congenital Aural Atresia and External Auditory Canal Stenosis: A Systematic Review

OBJECTIVE

Patients with congenital external auditory canal (EAC) abnormalities are at risk of developing cholesteatoma and often undergo surveillance imaging to detect it. The aims of this systematic review are to determine the incidence of cholesteatoma in patients with congenital aural atresia (CAA) and patients with congenital EAC stenosis and to investigate the most common age of cholesteatoma diagnosis. This information will help clinicians decide which patients require surveillance scanning, as well as the timing of imaging.

DATA SOURCES

Ovid MEDLINE, Embase, CENTRAL, and Web of Science databases.

REVIEW METHODS

A systematic literature review following the PRISMA guidelines was performed. The data sources were searched by 2 independent reviewers, and articles were included that reported on CAA or congenital EAC stenosis with a confirmed diagnosis of cholesteatoma. The selected articles were screened separately by 3 reviewers before reaching a consensus on the final articles to include. Data collection on the number of patients with cholesteatoma and the age of diagnosis was performed for these articles.

RESULTS

Eight articles met the inclusion criteria. The incidence of cholesteatoma was 1.7% (4/238) in CAA and 43.0% (203/473) in congenital EAC stenosis. The majority of patients with congenital EAC stenosis that developed cholesteatoma were diagnosed at age <12 years.

CONCLUSION

CAA is associated with a low risk of cholesteatoma formation, and surveillance imaging is unnecessary in asymptomatic patients. EAC stenosis is strongly associated with cholesteatoma, and a surveillance scan for these patients is recommended prior to 12 years of age with close follow-up into adulthood.

[Clinical analysis and surgical treatment of congenital external auditory canal stenosis complicated with external auditory canal cholesteatoma]

Objective:To investigate the clinical features, diagnosis, and treatment experience of congenital stenosis of an external auditory canal with external auditory canal cholesteatoma. Methods:The clinical data of 152 patients（153 ears） with congenital external auditory canal stenosis complicated with external auditory canal cholesteatoma treated in the Department of Otorhinolaryngology Head and Neck Surgery of Beijing Tongren Hospital affiliated to Capital Medical University from January 2009 to December 2019 were analyzed retrospectively, including the age of onset, clinical manifestations, signs, audiology, high-resolution computed tomography（HRCT） of the temporal bone, mode of operation and so on. According to the preoperative imaging findings, intraoperative findings,and pathological results, 152 patients with congenital external auditory canal stenosis with external auditory canal cholesteatoma were treated with canaloplasty and tympanoplasty while clearing the cholesteatoma. Results:All patients were followed up for 2-2.5 years, there was no recurrence of cholesteatoma, and the reconstructed external auditory canal was spacious. The hearing levels of 108 ears who underwent hearing reconstruction were significantly improved, and the average hearing threshold was reduced by 20-35 dB. Conclusion:The stenosis of the external auditory meatus is easy to be complicated with cholesteatoma of the external auditory canal,and the occurrence of cholesteatoma of the external auditory canal is directly related to the diameter of the external auditory canal meatus.But the time of occurrence of the cholesteatoma is not directly related to the diameter of the external auditory canal. Severe congenital stenosis of the external auditory canal with auricle deformity is easy to be missed and misdiagnosed due to retroauricular redness, swelling, and ulceration. For this kind of patient, cholesteatoma should be treated first, and then plastic surgery such as auricle reconstruction should be performed. Retroauricular incisions should be avoided to create conditions for auricle reconstruction in the future.

Congenital Aural Stenosis With Cholesteatoma

OBJECTIVE

Compare surgical and audiological outcomes of patients with congenital aural stenosis (CAS) with cholesteatoma to patients with CAS without cholesteatoma and patients with complete congenital aural atresia (CCAA).

STUDY DESIGN

Retrospective case series.

SETTING

Tertiary care hospital.

PATIENTS

Patients with CAS (with and without cholesteatoma) and CCAA.

INTERVENTION

Surgery for CAS/CAA.

MAIN OUTCOME MEASURES

Patients with CAS and CAA undergoing surgical repair from June 2004 to July 2020 were identified from an institutional database. Included patients were divided by presence of a canal cholesteatoma. Clinical history, pre- and postoperative audiometric data, and clinical outcomes were compared.

RESULTS

Of the 283 patients (300 ears), 18 (19 ears) had a canal cholesteatoma. When compared to ears without cholesteatoma (CCAA ears plus CAS ears without cholesteatoma), ears with cholesteatoma were more likely to be younger (9.2 ± 6.6 vs. 11.5 ± 9.2; p = 0.015), female (66.7% vs. 38.1%; p = 0.02; OR 3.2, 95% CI 1.18-8.9), and have normal/Grade I microtia (47.4% vs. 9.6%; p < 0.0001; OR 0.12, 95% CI 0.044-0.32), but not a history of draining ear (5.3% vs. 0%; p = 0.05; OR 0.06, 95% CI 0.004-0.999). Preoperative audiometric data demonstrated a lower mean air-bone gap (45.8 dB vs. 52.3 dB; p = 0.009) and better speech reception threshold (48.7 dB vs. 57.4 dB; p = 0.0004) in cholesteatoma ears. Postoperatively, ears with cholesteatoma were more likely to close the ABG within 20 dB (p = 0.001; OR 0.19, 95% CI 0.072-0.52). No patient in the cholesteatoma group developed post-operative bony/soft-tissue stenosis (0% vs. 9.7%; p = 0.65; OR 1.61; 0.21-12.6) or required revision surgery (0% vs. 11%; p = 0.38; OR 2.46, 0.32-19).

CONCLUSIONS

Patients with CAS and cholesteatoma have better audiometric outcomes and likely a more durable repair with a decreased need for revision possibly secondary to greater embryologic development of the meatus, ear canal, and middle ear space despite the cholesteatoma.

Prevalence of middle ear malformation and outcomes of tympanoplasty and/or canalplasty in patients with and without congenital external auditory canal stenosis

OBJECTIVE

To compare the prevalence of middle ear malformations between patients with and without congenital external auditory canal stenosis (CEACS) and to investigate the outcomes of tympanoplasty and/or canalplasty in terms of tympanic membrane (TM) size and external auditory canal (EAC) stenosis in patients with middle ear malformation.

METHODS

Twenty-five patients who underwent primary tympanoplasty and/or canalplasty for middle ear malformation at a tertiary academic medical center were retrospectively reviewed. CEACS was defined as an EAC diameter of 4 mm or less. Intraoperative findings, including irregularity of the ossicles, facial nerve, or chorda tympani; size of the TM and EAC on computed tomography; and pre- and postoperative hearing level, were collected.

RESULTS

We included 7 and 18 patients with and without CEACS, respectively. The malleus handle defect, anterior deviation of the chorda tympani, and small TM (≤7 mm) (p-values 0.015, <0.001, and 0.003, respectively; Fisher's exact test) had significantly higher prevalence in patients with CEACS than in those without. The mean postoperative air-bone gap (ABG) in patients with CEACS was not significantly different from that in patients with normal-sized EAC (20.6 dB and 19.5 dB, respectively; p-value, 0.121; Mann-Whitney U test). No difference was observed in mean postoperative ABG between patients with small TM and those with normal-sized TM (19.2 dB and 20.0 dB, respectively; p-value, 0.469; Mann-Whitney U test).

CONCLUSION

Patients with CEACS were more likely to have malleus handle defect, anterior deviation of the chorda tympani, and small TM than those without CEACS. Hearing outcome of patients with CEACS and a malformed malleus and/or incus might be equivalent to that of patients without CEACS following tympanoplasty and/or canalplasty, regardless of the EAC or TM size.

Rat Model of External Auditory Canal Stenosis

HYPOTHESIS

Circumferential electrocautery injury of the rat external auditory canal (EAC) can induce a reproducible animal model of acquired stenosis.

BACKGROUND

Acquired EAC stenosis may occur as a result of chronic inflammation or trauma to the EAC skin and is characterized by narrowing of the EAC, retention of debris, and hearing loss. Treatment is surgery but it is often complicated by restenosis. A reliable and inexpensive animal model of EAC stenosis has not been described. There have been no studies correlating the extent of EAC injury with the extent of stenosis.

METHODS

Rats received a 25, 50, or 75% circumferential EAC injury with electrocautery. The extent of resulting stenosis was quantified 21 days following injury. The nature of the injury and healing response was assessed with histology.

RESULTS

A 25% circumferential injury led to 4 to 34% stenosis (mean, 13%), 50% injury resulted in 43 to 100% stenosis (mean, 73%), and 75% injury resulted in 94 to 100% stenosis (mean=99%, p < 0.0001). The 50% circumferential injury produced 30 to 75% stenosis in five of eight ears, the remainder had >75% stenosis. Wounded ears showed evidence of intact cartilage and epithelium, with increased thickness of the subepithelial layer and localized fibrosis.

CONCLUSIONS

Electrocautery injury in the ventral aspect of the rat EAC resulted in reproducible EAC stenosis. This rat model may be useful in studying therapy to prevent acquired EAC stenosis due to acute injury. The correlation of the extent of injury (circumference) with resulting stenosis may inform clinical management of EAC injuries.

Anatomy and Development of the Mammalian External Auditory Canal: Implications for Understanding Canal Disease and Deformity

The mammalian ear is made up of three parts (the outer, middle, and inner ear), which work together to transmit sound waves into neuronal signals perceived by our auditory cortex as sound. This review focuses on the often-neglected outer ear, specifically the external auditory meatus (EAM), or ear canal. Within our complex hearing pathway, the ear canal is responsible for funneling sound waves toward the tympanic membrane (ear drum) and into the middle ear, and as such is a physical link between the tympanic membrane and the outside world. Unique anatomical adaptations, such as its migrating epithelium and cerumen glands, equip the ear canal for its function as both a conduit and a cul-de-sac. Defects in development, or later blockages in the canal, lead to congenital or acquired conductive hearing loss. Recent studies have built on decades-old knowledge of ear canal development and suggest a novel multi-stage, complex and integrated system of development, helping to explain the mechanisms underlying congenital canal atresia and stenosis. Here we review our current understanding of ear canal development; how this biological lumen is made; what determines its location; and how its structure is maintained throughout life. Together this knowledge allows clinical questions to be approached from a developmental biology perspective.

Measurement method for external auditory canal and clinical application in congenital aural stenosis

OBJECTIVE

To describe a measurement method for external auditory canal (EAC), especially in congenital aural stenosis (CAS).

METHODS

High-resolution CT (HRCT) datasets of CAS were imported into the MIMICS 15.0 software for image processing. We used two methods to evaluate the degree of CAS. One is sagittal reconstruction measurement method, the minor axis of the bony ear canal was measured in each layer using sagittal reconstruction. The other is Matlab procedure calculation, we calculated the midpoint axis values of the EAC in each Frankfurt plane. Finally, we compared the minimum value of each method, and verified the sagittal reconstruction measurement method retrospectively in the CAS cases without cholesteatoma who had undergone meatoplasty.

RESULTS

Twenty CAS cases were selected using the sagittal reconstruction measurement method and Matlab procedure calculation to evaluate the degree of CAS. The mean age was 9.55 ± 2.85 years old (range: 6-15). The mean degree of CAS was 2.09 ± 0.50 mm by sagittal reconstruction measurement method and 2.03 ± 0.58 mm by Matlab procedure calculation. There were no significant differences in the two groups (t = -1.371, p = 0.186). A total of 94 HRCT datasets were imported into MIMICS for verification. The mean age was 11.66 ± 6.56 years old (range: 6-39). Mean stenosis of EAC at surgery was 2.88 ± 0.93 mm (range: 1-4) by using sagittal reconstruction measurement method.

CONCLUSIONS

Matlab procedure calculation is precise but relatively complicated and is only for scientific research. The sagittal reconstruction measurement method to calculate the most stenotic part of the bony ear canal is relatively simple and accurate to evaluate the degree of CAS. In cases of CAS without cholesteatoma, the precise measurement was critical for the next consultation.

Congenital soft tissue stenosis of the external auditory canal with canal cholesteatoma: Case report and literature review

Congenital external auditory canal stenosis (EACS) is a spectrum of abnormalities affecting the external and middle ear. We report a 6 year-old patient with EACS affecting the lateral fibrocartilaginous canal that was successfully repaired. This patient highlights a variant of EACS characterized by lateral soft tissue narrowing with normal osseous development. Most previous studies of CAA have described severe forms associated with complete atresia, bony stenosis, and middle ear malformations. Stenosis affecting only the fibrocartilaginous canal is a milder form resulting from premature arrest of the canalization process during embryologic development, and may predispose to cholesteatoma formation.

Modified meatotympanoplasty for external auditory canal stenosis and lateralized tympanic membrane: a preliminary study

Background: The surgical treatment of external auditory canal stenosis (EACS) and lateralized tympanic membrane (LTM) is challenging because there is a high risk of postoperative complications.Objectives: The aim of this study was to evaluate the postoperative hearing levels and other outcomes of 10 cases with EACS and LTM.Materials and methods: This was a retrospective preliminary study of patients with EACS and LTM who underwent meatotympanoplasty from 2008 to 2018. Their mean age at surgery was 31.6 years. The surgeries were performed taking into consideration the following: (1) creating a large EAC and functioning tympanic membrane (TM) and (2) avoiding complete mastoidectomy to prevent postoperative cavity problems.Results: The mean follow-up period was 3 years 10 months. The average preoperative and postoperative air-bone gaps (ABGs) were 40.4 dB and 23.0 dB, respectively, and there was a significant difference. A postoperative ABG less than 30 dB was achieved in 80% (8/10) of patients. Four cases had postoperative complications (re-stenosis of the EAC and/or re-lateralization of the TM).Conclusions and significance: The postoperative results presented were comparable to those of previous surgical techniques; however, further development is needed to prevent postoperative complications and earn better hearing results.

Long-term Audiometric Outcomes After Atresiaplasty for Congenital Aural Atresia

OBJECTIVE

Describe long-term trends and stability of hearing outcomes for patients undergoing primary congenital aural atresia (CAA) repair.

STUDY DESIGN

Retrospective chart review.

SETTING

Single academic, tertiary referral center.

PATIENTS

Children and adults who underwent primary CAA repair between 1980 and 2017.

INTERVENTION

CAA repair.

MAIN OUTCOME MEASURES

Long-term (> 1 yr) postoperative three-tone (500, 1000, 2000 Hz) air conduction pure-tone average (AC PTA) compared with the immediate (within 90 d of surgery) postoperative audiogram.

RESULTS

The mean preoperative AC PTA was 59.6 dB HL. CAA repair improved hearing an average of 30.5 dB, but hearing declined by 8.2 dB over the long-term follow-up period (mean 4.4 yr; range 1-15.7 yr), leaving a final mean improvement of 22.2 dB (final mean AC PTA 37.3 dB HL). Two-thirds (92 of 138 ears) had an AC PTA ≤ 30 dB HL recorded in the first year after surgery. At the last follow-up test, 64% had "stable" hearing defined as no more than a 10 dB decline in AC PTA compared with the immediate postoperative audiogram; 21% had a 10 to 20 dB decline, 8% a 20 to 30 dB decline, and 7% declined > 30 dB.

CONCLUSIONS

All patients enjoyed improvement in AC PTA after surgery (preoperative minus the best postoperative PTA, mean = 34 dB, range = 3.3-52 dB). Hearing declined by an average 8.2 dB over the long-term leaving a final average AC PTA of 37.4 dB HL. Sixty-four percent of patients exhibited stable (< 10 dB loss) hearing over time; 36% lost 10 dB or more over the long-term follow-up period. Hearing results typically stabilize over time with most of the change occurring in the first 3 years after CAA repair. Bone conduction thresholds remained stable over the study period.

International Consensus Recommendations on Microtia, Aural Atresia and Functional Ear Reconstruction

The aim of this report is to provide international recommendations for functional ear reconstruction in patients with microtia and aural atresia. All patients with microtia and external auditory atresia should be seen in the setting of a multidisciplinary team and agreed treatment outcomes should be measured, so that techniques, approaches, and results can be compared. The methods are expert opinion from the members of the International Microtia and Atresia Workgroup (IMAW). The consensus recommendations reported herein take into account the variability in practice patterns present among experts in the field; the degree of consensus was quantified by presenting the percentage of above authors who agree or partially agree with each statement. Recommendations include the definition and classification of microtia/atresia, treatment of microtia, treatment of congenital aural atresia, flowchart of functional ear reconstruction, and future research directions. Patients with microtia and aural atresia can be guided by the consensus recommendations provided herein.

Morphological Characteristics of Osseous External Auditory Canal and Its Relationship With External Auditory Canal Cholesteatoma in Patients With Congenital Aural Stenosis

OBJECTIVE

To investigate the characteristics of stenotic external auditory canal (EAC) (e.g., shape, length, orientation, and curvature) and to compare them with those of the cholesteatoma and no cholesteatoma groups, which may help to explain cholesteatoma formation to a certain degree.

METHODS

Computed tomography scans of two groups of patients (with and without EAC cholesteatoma) were analyzed. We determined the degree of microtia, the stenosis of EAC, radius and curvature of osseous EAC bending (abbreviated as OEB-r and OEB-c, respectively), and other anatomic parameters of EAC by using Mimics and Matlab.

RESULTS

There was no significant difference in the degree of microtia between the cholesteatoma and no cholesteatoma groups using the Marx grading system. Additionally, no significant difference was found in the stenosis of EAC between the two groups. The OEB-r was smaller in the cholesteatoma group (4.62 ± 0.62 mm) than in the no cholesteatoma group (7.41 ± 0.50 mm), and the OEB-c was found to be larger in the cholesteatoma group (1.55 ± 0.05 × 10 mm) than in the no cholesteatoma group (1.10 ± 0.10 × 10 mm). Moreover, the OEB-c (OR, 8.60; 95% CI, 2.67-27.75) was associated with EAC cholesteatoma formation.

CONCLUSION

The curvature of osseous EAC in the cholesteatoma group was significantly larger than that in the no cholesteatoma group. It is suggested that the curvature of osseous EAC was a risk factor for EAC cholesteatoma formation.