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

Imaging findings of isolated congenital middle ear malformation on high-resolution computed tomography

PURPOSE

This study aims to analyze the imaging features of isolated congenital middle ear malformation (CMEM) on high-resolution computed tomography (HRCT).

METHODS

We retrospectively collected patients with surgically confirmed diagnosis of isolated CMEM in our hospital between January 2018 and June 2023. All patients underwent HRCT before surgery. The preoperative imaging findings were analyzed by neuroradiologists with full knowledge of the intraoperative findings.

RESULTS

37 patients were included in this study, including 25 males and 12 females, with a median age of 16 years. A total of 44 ears underwent surgery. The most commonly affected structures were incudostapedial joint, incus long process, and stapes superstructure, followed by stapes footplate, oval window, incudomalleolar join, tympanic segment of the facial nerve canal, incus body, incus short process and malleus. All incus defect/hypoplasia/malposition, stapes superstructure deformity, malleus deformity, incudostapedial joint discontinuity, and facial nerve canal malposition/abnormal bifurcation could be observed on HRCT. Additionally, 96.0% of stapes superstructure defect, 85.7% of oval window atresia, and 41.7% of incudomalleolar joint fusion, could be visualized on HRCT. HRCT could not show ossicular soft tissue pseudo-connection and stapes footplate fixation.

CONCLUSIONS

Preoperative HRCT is an important tool for diagnosing isolated CMEM. The advantages of HRCT lie in its ability to detect ossicular defects/deformities, incudostapedial joint discontinuity, oval window atresia, and facial nerve abnormalities. However, it has a low detection rate for incudomalleolar joint fusion and cannot show ossicular soft tissue pseudo-connection and stapes footplate fixation.

Diagnosis and Management of Unexplained Conductive Hearing Loss With Intact Tympanic Membrane: A Systematic Review

Objective: To analyze the etiology, diagnosis, and treatment of unexplained conductive hearing loss (UCHL) with intact tympanic membrane. Methods: A systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 642 articles were retrieved from databases such as PubMed, Embase, Web of Science, and Cochrane. Fifty-four research articles and 21 case reports were screened out according to the inclusion and exclusion criteria for analysis of the etiology of UCHL. Seven research articles with UCHL who underwent exploratory tympanotomy were selected for data extraction and analysis of clinical characteristics. Results: UCHL is a common manifestation of various diseases, including congenital ossicular anomalies (COA), otosclerosis (OTS), congenital middle ear cholesteatoma (CMEC), oval window atresia, superior semicircular-canal dehiscence, congenital stapedial footplate fixation, middle ear osteoma or adenoma, congenital ossification of stapedial tendon, and so on. A total of 522 patients were included in the 7 articles; among whom OTS showed a tendency to increase with age. The main symptoms were hearing loss, followed by tinnitus, dizziness, ear fullness, ear pain, facial paralysis. A total of 87.5% to 93.0% patients with COA manifested as nonprogressive deafness that occurred since childhood, with tinnitus incidence of 15.6% to 30.2%, and 86.4% to 96.4% patients with OTS presented with progressive hearing loss, with tinnitus incidence of 60.1% to 90.9%. The diagnosis positive rate of high-resolution computed tomography (HRCT) was 33.8% to 87.1%, and CMEC was higher than that of COA (83.3%-100% vs 28.6%-64%). All the articles reported good hearing recovery. The most common surgical complications included taste abnormalities, tinnitus, and dizziness. Conclusion: UCHL presents with similar clinical manifestations and poses challenges in preoperative diagnosis. Exploratory tympanotomy is the primary method for diagnosis and treatment, with good prognosis after removing the lesion and reconstructing hearing during the operation. Children can also safely undergo the surgery.

Transcanal endoscopic management of isolated congenital middle ear malformations

BACKGROUND

A few studies have reported transcanal endoscopic management of isolated congenital middle ear malformations (CMEMs).

OBJECTIVE

The purpose of this study is to describe our surgical experience in endoscopic ear surgery for isolated CMEMs and evaluate the surgical effect of hearing reconstruction.

METHODS

From January 2017 to January 2022, a retrospective study was performed on 36 patients (37 ears) with isolated CMEMs who all underwent endoscopic surgery. Demographic data, high-resolution computed tomography (HRCT) findings, intraoperative findings, surgical management and audiometric data were recorded.

RESULTS

Anomalies were categorized according to the Teunissen and Cremers classification system: 8 ears were categorized as class I, 8 ears as class II, 19 ears as class III and 2 ears as class IV. The air conduction pure tone average (AC-PTA) of 37 cases was 61.5 ± 8.6 dB preoperatively and 29.6 ± 6.9 dB postoperatively (p < 0.001). The mean preoperative air-bone gap (ABG) significantly decreased from 43.1 ± 8.7 dB to 12.8 ± 5.5 dB postoperatively. 36 of 37 cases (97%) met the criteria for successful operation.

CONCLUSION

Isolated CMEMs are mainly manifested as aplasia of the stapes' superstructure and dysplasia of the long process of the incus. Transcanal endoscopic surgery seems a safe technique for the management of isolated CMEMs.

Congenital duplicated incus in the mastoid cavity

Many congenital ossicular chain malformations exist, usually involving ossicular deformities, fixation, absence, or discontinuity. Duplication of ossicles has not been reported, much less a duplicated ossicle located in the mastoid. We present a case of a patient who had a duplicated incus in the mastoid antrum.

Congenital Anomalies of the Ossicular Chain: Surgical and Audiological Outcomes

Objectives:

In this study, we aim to analyze audiometric outcomes of middle ear surgery in patients with congenital middle ear anomalies.

Methods:

In this single center retrospective cohort study, audiological outcomes were extracted from patient files. Patients with a congenital middle ear anomaly treated surgically in a tertiary referral center between June 2015 and December 2020 were included. Pre- and postoperative short- and long-term audiometric data (at ≥3 and ≥10 months respectively) were compared to analyze hearing outcomes.

Results:

Eighteen ears (15 patients) were treated surgically with an exploratory tympanotomy. At short term follow up statistically significant improvements in air conduction thresholds and air-bone gaps were found. Hearing improved in 94.4% (17/18) of operated ears. Successful outcome, defined as an air-bone gap closure to within 20 dB after surgery, was reached in 44.4% (8/18). Serviceable hearing (air conduction ≤30 dB) was reached in 55.6% (10/18). Negative outcome (any significant deterioration in hearing) occurred in 1 patient: in this ear otitis media occurred during the postoperative course. At long term follow up, available for 50% of the cohort, hearing remained stable in 5 ears, improved in 1 ear and deteriorated in 3, all of which underwent revision surgery. Sensorineural hearing loss due to surgery, or other complications, were not encountered.

Conclusion:

middle ear surgery was found to be an effective treatment option to improve hearing in this cohort of patients with congenital middle ear anomalies. Surgical goals of obtained gain in air conduction thresholds and serviceable hearing levels were met by most patients without the occurrence of any iatrogenic sensorineural hearing loss.

Endoscopic Ossiculoplasty for the Management of Isolated Congenital Ossicular Chain Malformation: Surgical Results in 16 Ears

OBJECTIVE

The aim of this study is to describe the clinical characteristics and intraoperative findings and further evaluate the efficacy of endoscopic ossiculoplasty for the management of isolated congenital ossicular chain malformation.

METHODS

A retrospective study was performed on 16 ears (15 patients) with the isolated congenital ossicular chain malformation who underwent endoscopic ossiculoplasty in our department from May 2017 to January 2019. Endoscopic exploratory tympanotomy was conducted to check the ossicular chain; at the same time, endoscopic ossiculoplasty was performed depending on intraoperative findings. Air-conduction thresholds, bone-conduction thresholds, and air-bone gaps (ABGs) were measured before and after surgery, and the hearing outcome was assessed at 6 months postoperatively.

RESULTS

The most common malformations of ossicular chain were the missing of the incus long process and stapes suprastructure. A serial assessment of the hearing status was conducted before and 6 months after surgery. It showed the mean postoperative pure-tone average (PTA) was significantly reduced, and the mean postoperative ABG was obviously closed, respectively (P < .001). The mean PTA gain was 36.3 ± 8.6 dB, and the ABG closure was 35.1 ± 8.3 dB; ABG closure to 20 dB or less and ABG closure to 10 dB or less were achieved in 14 cases (87.5%) and 5 cases (31.3%), respectively. No differences were observed in postoperative hearing outcome between type Ⅲ cases and type Ⅳ cases; however, cases with partial ossicular replacement prosthesis implantation showed a larger hearing gain (P = .049) and a higher proportion of postoperative ABG less than 10 dB (P = .021). No facial palsy and significant sensorineural hearing loss occurred; all patients completed the surgery without the need of canalplasty, and the chorda tympani nerve was preserved in all patients.

CONCLUSIONS

This research showed endoscopic surgery was effective in the diagnosis and management of isolated congenital ossicular chain malformation; the endoscopic ossiculoplasty provides an alternative method to manage congenital ossicular chain malformation, with comfortable hearing outcome and the advantage of excellent vision and less invasion.

Isolated Congenital Middle Ear Malformations: Comparison of Preoperative High-Resolution CT and Surgical Findings

Objectives:

To compare preoperative temporal bone high-resolution computed tomography (HRCT) readings to intraoperative findings during exploratory tympanotomy for suspected cases of isolated congenital middle ear malformations (CMEMs) and summarize the malformations that can and cannot be diagnosed with HRCT.

Methods:

A retrospective study was conducted. All cases were confirmed as isolated CMEMs during surgery. Detailed clinical records were reviewed, with a focus on imaging and surgical findings.

Results:

One hundred and thirty-two patients and 145 ears were reviewed. Ninety cases (62.1%) could be identified as isolated CMEMs and at least one as middle ear anomaly using preoperative HRCT. Fifty-five cases (37.9%) were reported to be completely normal and the patients underwent exploratory tympanotomy to determine the final diagnosis. Stapes fixation, either alone or associated with other ossicular chain anomalies, contributed to 53.1% of the cases. Most cases of aplasia or dysplasia of the ossicular chain, for example, aplasia/dysplasia of the long process of the incus, aplasia of the stapes’ superstructure, and atresia of the oval window were easily identified in preoperative HRCT. However, fixation of the ossicular chain can be elusive in HRCT, and exploratory tympanotomy is needed for a definitive diagnosis.

Conclusions:

HRCT provides helpful preoperative clinical information in CMEM and may obviate the need for middle ear exploration in some cases. The negative findings (anomalies that are difficult to identify through preoperative HRCT) and the positive findings (anomalies that are relatively easy to identify through preoperative HRCT) were summarized.