Piezoelectric Multi-Channel Bilayer Transducer for Sensing and Filtering Ossicular Vibration.

This paper presents an acoustic transducer for fully implantable cochlear implants (FICIs), which can be implanted on the hearing chain to detect and filter the ambient sound in eight frequency bands between 250 and 6000 Hz. The transducer dimensions are conventional surgery compatible. The structure is formed with 3  × 3 × 0.36 mm active space for each layer and 5.2 mg total active mass excluding packaging. Characterization of the transducer is carried on an artificial membrane whose vibration characteristic is similar to the umbo vibration. On the artificial membrane, piezoelectric transducer generates up to 320.3 mVpp under 100 dB sound pressure level (SPL) excitation and covers the audible acoustic frequency. The measured signal-to-noise-ratio (SNR) of the channels is up to 84.2 dB. Sound quality of the transducer for fully implantable cochlear implant application is graded with an objective qualification method (PESQ) for the first time in the literature to the best of the knowledge, and scored 3.42/4.5.

[Advances in research on treatment of tympanosclerosis].

Tympanosclerosis is the hyaline degeneration and calcium deposition of the lamina propria of tympanic membrane and the submucosa of middle ear under long-term chronic inflammatory stimulation. At present, treatment primarily involves the surgical removal of sclerotic foci and reconstruction of auditory ossicular chain. However, excision of sclerotic lesions near critical structures like the facial nerve canal and vestibular window may result in complications like facial paralysis, vertigo, and sensorineural hearing loss. Developing safer and more effective treatments for tympanosclerosis has become an international research focus. Recent years have seen novel explorations in the treatment of tympanosclerosis. Therefore, this article reviews the latest advancements in research on the treatment of tympanosclerosis.

The human middle ear in motion: 3D visualization and quantification using dynamic synchrotron-based X-ray imaging.

The characterization of the vibrations of the middle ear ossicles during sound transmission is a focal point in clinical research. However, the small size of the structures, their micrometer-scale movement, and the deep-seated position of the middle ear within the temporal bone make these types of measurements extremely challenging. In this work, dynamic synchrotron-based X-ray phase-contrast microtomography is used on acoustically stimulated intact human ears, allowing for the three-dimensional visualization of entire human eardrums and ossicular chains in motion. A post-gating algorithm is used to temporally resolve the fast micromotions at 128 Hz, coupled with a high-throughput pipeline to process the large tomographic datasets. Seven ex-vivo fresh-frozen human temporal bones in healthy conditions are studied, and the rigid body motions of the ossicles are quantitatively delineated. Clinically relevant regions of the ossicular chain are tracked in 3D, and the amplitudes of their displacement are computed for two acoustic stimuli.

Evaluation of the ear ossicles with photon-counting detector CT.

Recently, computed tomography with photon-counting detector (PCD-CT) has been developed to enable high-resolution imaging at a lower radiation dose. PCD-CT employs a photon-counting detector that can measure the number of incident X-ray photons and their energy. The newly released PCD-CT (NAEOTOM Alpha, Siemens Healthineers, Forchheim, Germany) has been in clinical use at our institution since December 2022. The PCD-CT offers several advantages over current state-of-the-art energy-integrating detector CT (EID-CT). The PCD-CT does not require septa to create a detector channel, while EID-CT does. Therefore, downsizing the anode to achieve higher resolution does not affect the dose efficiency of the PCD-CT. CT is an indispensable modality for evaluating ear ossicles. The ear ossicles and joints are clearly depicted by PCD-CT. In particular, the anterior and posterior legs of the stapes, which are sometimes unclear on conventional CT scans, can be clearly visualized. We present cases of congenital anomalies of the ossicular chain, ossicular chain dislocation, tympanosclerosis, and cholesteatoma in which PCD-CT was useful. This short article reports the usefulness of PCD-CT in the 3D visualization of the ear ossicles.

A New Floating Piezoelectric Microphone for Fully Implantable Cochlear Implants in Middle Ear.

OBJECTIVE: Our team designed a long-lasting, well-sealed microphone, which uses laser welding and vacuum packaging technology. This study examined the sensitivity and effectiveness of this new floating piezoelectric microphone (NFPM) designed for totally implantable cochlear implants (TICIs) in animal experiments and intraoperative testing. METHODS: Different NFPM frequency responses from 0.25 to 10 kHz at 90 dB SPL were analyzed using in vivo testing of cats and human patients. The NFPM was tested in different positions that were clamped to the ossicular chains or placed in the tympanic cavity of cats and human patients. Two volunteers' long incus foot and four cats' malleus neck of the ossicular chain were clamped with the NSFM. The output electrical signals from different locations were recorded, analyzed, and compared. The NFPM was removed after the test without causing any damage to the middle-ear structure of the cats. Intraoperative tests of the NFPM were performed during the cochlear implant surgery and the cochlear implant surgery was completed after all tests. RESULTS: Compared with the results in the tympanic cavity, the NFPM could detect the vibration from the ossicular chain more sensitively in cat experiments and intraoperative testing. We also found that the signal output level of the NFPM decreased as the acoustic stimulation strength decreased in the intraoperative testing. CONCLUSION: The NFPM is effective in the intraoperative testing, making it feasible as an implantable middle-ear microphone for TICIs. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:937-944, 2024.

Anatomic and morphometric examination of auditory ossicles in sheep.

It is important to know the morphometry of the auditory ossicles for middle ear surgical applications. The present study aims to investigate the morphometric measurements of sheep auditory ossicles and the relationship between these ossicles. In this study, 100 malleus, incus and stapes of 50 Akkaraman sheep were examined using at trinocular stereo microscope and a total of 19 morphometric measurements were taken. The mean values of the morphometric measurements were obtained, and correlation analysis was performed between each part of each auditory ossicle. Similarities were found between the measurements of the lengths of the malleus, manubrium mallei and incus, and the width of the base of the stapes with morphometric measurements in human auditory ossicles. A significant positive correlation was found between the length of the malleus with the length of the manubrium mallei, between the length of the incus with the lengths of the long crus and corpus incudis, between the length of the stapes with the lengths of the rostral crus, caudal crus, caput stapedis, and the length and width of the intercrural foramen. Due to the anatomic similarities between sheep and human auditory ossicles, it was concluded that the auditory ossicles of sheep are suitable for use in the training of human ear surgery applications.

Wideband frequency impedance for diagnosis of ossicular chain abnormality.

BACKGROUND: The accurate estimation of the ossicular chain abnormalities using existing functional examinations has been difficult. AIMS/OBJECTIVES: This study aimed to verify the accuracy of preoperative diagnosis of ossicular chain abnormalities using a wideband frequency impedance (WFI) meter, which can measure the dynamic characteristics of the middle ear. MATERIAL AND METHODS: Retrospective cohort study. Fourteen ears of patients with ossicular chain abnormalities that were definitively diagnosed surgically were included in this study. The following data were collected for each participant: sound pressure level (SPL) curve measured using the WFI meter and a sweep frequency impedance (SFI) meter, WFI measurements plotted on the resonance frequency (RF)-ΔSPL plane, distribution map of the dynamic characteristics of the middle ear, preoperative audiometry results, and the definitive surgical diagnosis. RESULTS: The SPL curve obtained using the WFI meter had lesser noise than that obtained using the SFI meter. The distribution map revealed that the ossicular chain separation range and ossicular chain fixation range were completely separated. The hearing data tended to be poor in cases with small ΔSPL. CONCLUSIONS AND SIGNIFICANCE: WFI can potentially enhance the accuracy of SFI. In addition, it can also be used for the classification of ossicular chain separation and fixation as well as the quantification of fixation in cases of ossicular chain anomalies that cannot be diagnosed using conventional tests.

Diagnosis and management of bilateral lipoma of the middle ear.

INTRODUCTION: Middle ear lipomas are rare, accounting for less than 1% of all middle ear tumours. To our knowledge there have been only 16 reported patients with middle ear lipoma. Only one of these had bilateral congenital middle ear lipomas. The aim of this review is to comprehensive overview the diagnosis and management of congenital lipomas of the middle ear. METHODS: A literature review was performed searching multiple data bases, using the key words "middle ear", AND "lipoma", AND "congenital". A total of 116 articles were identified. One hundred were excluded on various criteria, leaving 16 articles for detailed review. Additionally, we report the second case of bilateral congenital middle ear lipoma. RESULTS: Based on this case report and literature review, the incidence of middle ear lipomas is greater in paediatric patients than in adult patients. Middle ear lipomas are distributed evenly between males and females. Three patients had recognised genetic syndromes, while five had prior ventilation tube placement. Clinically patients present with conductive hearing loss and middle ear effusions. In some cases, presence of a white or yellow mass behind the anterior aspect of the tympanic membrane is recognised. The most common location of the masses is in the anterosuperior quadrant of the middle ear, the site of predilection for small congenital cholesteatomas. An MRI scan is most useful in distinguishing between lipoma and cholesteatoma. All cases reported surgical excision of the middle ear lipoma. There was no evidence of recurrence noted up to 4 years follow up. CONCLUSION: Though rare, congenital lipomas of the middle ear should be a differential diagnosis of a middle ear masses. Early identification can allow surgical lipoma resection with minimal disruption to the ossicular chain. Though there is currently no consensus regarding management, surgical removal and appropriate reconstruction of the ossicular chain if needed, is appropriate.

[Analysis of medium and long term efficacy of ossicle chain bypass technique in treatment of tympanosclerosis].

Objective:For tympanosclerosis patients with ossicular chain fixation, we use ossicular chain bypass technique and evaluate its long-term effects. Methods:From June 2017 to June 2019, 147 patients with tympanosclerosis who underwent middle ear surgery with otoscopy in Yinchuan First People's Hospital were reviewed. The subjects were divided into three groups according to the implemented operation plan, 51 cases in the ossicular chain mobilization group（OCM）, 56 cases in the ossicular chain bypass reconstruction group（OCB）, and 40 cases in the malleus-incus complex resection reconstruction group（MICR）. Through a three-year follow-up, the medium and long-term effects of different operation plans were compared and analyzed. Results:There was no significant difference among the three groups in the incidence of tympanic membrane perforation, delayed facial nerve palsy, and the dispatch and displacement of PORP. The incidence of tympanic membrane retraction pocket or cholesteatoma after operation in OCB group（0） was significantly lower than that in OCM group（11.76%） and MICR group（7.5%）（P<0.05）. At 12 months after operation, ΔABG of OCB group and MICR group were better than that in the OCM group（P<0.05）. At 36 months after operation, ΔABG of OCB group was better than that in the OCM group（P<0.05）, and there was no significant difference between OCB group and MICR group. The audiological performance of patients with epitympanic sclerosis（ETS） at 12, 24 and 36 months after operation was better than that of patients with posterior tympanosclerosis（PTS） and total tympanosclerosis（TTS）（P<0.05）. Conclusion:Compared with patients undergoing ossicular chain mobilization and malleus-incus complex resection for ossicular chain reconstruction, patients with tympanosclerosis undergoing bypass technique have better and stable hearing prognosis in medium and long term. This technique can effectively prevent the formation of retracted pocket and cholesteatoma in patients with tympanosclerosis after operation.

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.

Impact of Otosclerosis on Auditory Ossicle Remodeling: A Scanning Electron Microscopy Analysis of Stapes Head Overloads.

BACKGROUND Otosclerosis is a pathology that interferes with the conduction of vibrations to the inner ear, triggering changes in the auditory ossicles and their associated joints due to mechanical overload. This study primarily aims to evaluate these overload-induced modifications in the stapes head resulting from the immobilization of the base of the third auditory ossicle in otosclerosis patients. MATERIAL AND METHODS We conducted a comparative analysis of patients undergoing their first surgery for otosclerosis. The test group consisted of 31 patients who underwent stapedotomy between 2020-2021. For comparison, we utilized a control group comprising stapes samples extracted during vestibular schwannoma surgeries via a transcochlear approach. A prospective analysis of bone tissue surface topography and chemical composition was executed using scanning electron microscopy (SEM). RESULTS SEM analysis of the stapes head in otosclerosis patients relative to the control group displayed no significant differences in chemical composition or the presence of otosclerotic foci. Nonetheless, various forms of bone tissue surface damage were noted on the stapes head in all otosclerosis patients. Mild changes were evident in 90% of the samples, while small linear bone tissue fractures were observed in 58% of the samples. Furthermore, minor osteophytic changes were detected in 16% of the samples. CONCLUSIONS The immobilization of the stapes base by otosclerotic foci instigates overloads in the incus-stapes joint, leading to the eventual remodeling of the stapes head articular surface.

Exclusive endoscopic ossiculoplasty with autologous material: step-by-step procedure and functional results.

PURPOSE: To describe the surgical procedure of exclusive endoscopic ossiculoplasty (EEO) with autologous grafts and evaluate audiological results, focusing on the advantages or drawbacks compared to the corresponding microscopic technique. METHODS: A retrospective review of consecutive adult and pediatric patients affected by chronic otitis media (COM) with or without cholesteatoma who underwent EEO was conducted. Only autologous ossiculoplasty was included in the study. The procedure was performed by experienced surgeons of our institution between November 2014 and September 2019. Hearing outcomes were evaluated using postoperative air-bone gap (ABG) and success rates in different subgroups of patients and different types of ossiculoplasty (OPL) were analyzed. Our results were finally compared with the existing literature regarding both microscopic and endoscopic ossicular chain reconstruction. RESULTS: In total, 74 endoscopic ossicular chain repair procedures performed within the study period met the inclusion criteria. Of these, 21 were pediatric patients (28%) and 53 were adults (72%). Surgical reconstruction procedures included 43 partial ossicular reconstructions (POR) and 31 total ossicular reconstructions (TOR). The postoperative ABG improved significantly compared to preoperative measurements, and the mean ABG closure was 7.85 dB HL (p = 0.00064). No statistically significant differences in audiological outcomes between TOR/POR techniques and pediatric/adult groups were found in our study cohort, with p values of 0.10 and 0.88, respectively. CONCLUSIONS: At present, EEO can be considered a valid surgical option for re-establishing a functioning ossicular chain with acceptable hearing restoration in children and adults. Further reports in wider case series are required to confirm these results.

Is pre-operative audiometry a reliable predictor of ossicular chain condition?

OBJECTIVE: Investigation of ossicular chain (OC) status before surgery is important for preoperative patient consultation. This research aimed to investigate the relationship between pre-operative audiometric values and intra-operative OC condition in a relatively large population of chronic otitis media (COM) surgeries. METHODS: In this descriptive-analytic cross-sectional study, we evaluated 694 patients who underwent COM surgeries. We analyzed pre-operative audiometric data and intraoperative findings including ossicular anatomy, ossicular mobility, and the condition of middle ear mucosa. RESULTS: The optimal cut-off values of pre-operative speech reception threshold (SRT), mean air-conduction (AC), and mean air-bone gap (ABG) for predicting OC discontinuity were 37.5 dB, 37.2 dB, and 28.4 dB, respectively. For the prediction of OC fixation, the optimal cut-off points of SRT, mean AC, and mean ABG were 37.5 dB, 40.3 dB, and 32.8 dB, respectively. The computing of Cohen's d (95 % confidence interval) demonstrated the greater mean ABG in ears with OC discontinuity in comparison with ears with normal ossicles in all types of pathologies. There was a descending trend of Cohen's d from cholesteatoma to tympanosclerosis and then to granulation tissue and hypertrophic mucosa. There was a substantial relation between the type of pathology and OC status (P < 0.001). Ears with tympanosclerosis plaque had the most fixed OC among all types of pathologies (40 ears, 30.8 %), and ears with no pathology had the most normal OC (135 ears, 83.3 %). CONCLUSIONS: The results supported the view that pre-operative hearing is a key determining factor for the prediction of OC status.

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.

Real-time monitoring of middle ear prosthesis coupling.

INTRODUCTION: In reconstructive middle ear surgery, acoustic quality has received a high level of attention in recent years. Careful intraoperative selection and positioning of passive middle ear prostheses during tympanoplasty with ossiculoplasty is essential to ensure satisfactory sound transmission and postoperative hearing outcome. The reconstruction quality of the ossicular chain (OC) can be evaluated intraoperatively using a surgical assistance system which is based on a real-time monitoring system (RTM system) that acquires the transmission (middle ear transfer function (METF)) with electromagnetic excitation of the OC. In this experimental study, the METF with electromagnetic excitation of the (reconstructed) OC was compared to usual acoustic excitation and the benefit of the RTM system was investigated for the implantation of partial (PORP) and total (TORP) prostheses. METHODS: Laser Doppler vibrometry (LDV) was used to measure the middle ear transfer function (METF) in 18 human temporal bones (TB). The RTM system uses electromagnetic excitation of the OC with a magnet placed on the umbo. Comparatively, measurements with the usual acoustical excitation, using an earphone in the external auditory canal, were performed. The measurements began with the intact OC, followed by real-time monitoring guided OC reconstruction with PORP and TORP. In addition, during the simulation of an intraoperative setting, the influence of the influence of opening (tympanomeatal flap lifted and pushed anteriorly) and closing (tympanomeatal flap folded back) the tympanic membrane on the measurements with the RTM system was determined. RESULTS: Electromagnetic and acoustic excitation of the intact and the reconstructed OC provided comparable METF. The application of the RTM system significantly improved the quality of the OC reconstruction. The METF increased by up to 10 dB over the entire frequency range during implantation of the PORP with positioning control by the RTM system. When using the TORP, the METF could be improved by up to 15 dB. The opening of the tympanomeatal flap did not affect the measurements with the RTM system at the reconstructed OC. CONCLUSION: In this TB study, we demonstrated that the quality of OC reconstruction (improved METF as a benchmark for improved transmission) could be significantly increased by means of a RTM system. Intraoperative studies should now be conducted to investigate to which quantitative extent the intraoperative reconstruction quality can be improved and whether or not this improvement also manifests in an increased (long-term) hearing outcome. This will enable conclusions to be drawn about the contribution of the intraoperative reconstruction quality to the (long-term) hearing outcome in the context of the conglomerate of various factors influencing the postoperative hearing outcome.

3D-printed custom ossicular prosthesis - methodology of design and LDV measurements in a cadaver study.

OBJECTIVE: In tympanoplasty, surgical reconstruction of the tympanic membrane and ossicular chain is well-established; however, its hearing results still require improvement. Custom 3D printing of individualized ossicular prostheses seems to be an attractive solution for optimal prosthesis adjustment and better hearing results. AIM: The aim was to design a custom ossicular prosthesis using a 3D printing method based on Cone-beam Computed Tomography (CBCT) scans and assess the acoustic conduction properties of such prosthesis. MATERIAL AND METHODS: A cadaver fresh frozen temporal bone was used. Based on CBCT images, a new incus prosthesis was designed and 3D printed. Next, canal wall-up tympanoplasty was performed. The intact ossicular chain and reconstructed 3D-printed prosthesis chain movements/vibrations were measured with Laser Doppler Vibrometer (LDV) system and analyzed in detail. RESULTS: The CBCT scans provided enough information about the anatomical structures. For frequencies 500 and 1000 Hz and 80 dB SPL sound intensity, collected velocities were higher for the intact ossicular chain than the 3D-printed ossicular prosthesis. The intensity thresholds for movement at 500 and 1000 Hz were lower in the intact ossicular chain than in the 3D-printed ossicular prosthesis. At 2000 Hz, there was the same intensity threshold value in the two measured circumstances. CONCLUSION: It is possible to design a custom individually fitted ossicular prosthesis using a 3D printing method based on CBCT scans. The acoustic conduction properties of such 3D-printed prosthesis showed differences in movability pattern between the intact and reconstructed ossicular chain. More data are needed to analyze the acoustic properties of such designed prostheses in detail. The results of our experiment showed the 3D-printed prosthesis presents the potential to be an interesting option for conductive hearing loss treatment caused by chronic otitis media and the ossicular chain defects.

[Etiology analysis and diagnosis of noninflammatory conductive hearing loss in children].

Objective:To investigate the etiology, diagnosis and treatment of noninflammatory conductive hearing loss in children. Methods:The clinical data of children patients admitted to the Eye & ENT Hospital of Fudan University from January 2019 to November 2022 were retrospectively analyzed. Results:A total of 179 cases（189 ears） were analyzed. The main symptoms from high to low were: ear tightness, hearing loss, earache, and facial paralysis. The degree of hearing loss was mild in 34 ears（19.5%）, moderate in 70 ears（40.2%）, moderate-severe in 52 ears（29.9%）, severe in 18 ears（10.3%）. The mean hearing threshold of otosclerosis was the highest（63.5±7.8） dB HL, and the mean air-bone gap of ossicular chain malformation was the largest（35.4±9.8） dB HL. The mean hearing threshold of the affected ear was（50.4±14.5） dB HL, and the mean air bone gap was（30.3±10.4） dB HL. After operation, the results were（36.1± 14.5） dB HL and（20.0±8.6） dB HL, respectively. Distribution of surgical methods for ossicular chain reconstruction: 88 ears（46.6%） of TORP, 49 ears（25.9%） of PORP, 8（4.2%） ears of Piston, 9 ears（4.8%） of autogenous ossicular reconstruction, and 35 ears（18.5%） of ossicular chain relaxation. CT diagnostic rate showed more sensitivity to malleus and incus abnormalities, the diagnosis rate of congenital middle ear cholesteatoma was the highest. The mean duration time of diagnosis was（2.2±2.9） years, while the diagnosis of ossicular chain malformation（[5.2±4.2]years）, otosclerosis（[4.4±4.1]years）, tympanosclerosis（[5.4±0.9]years） took longer. Conclusion:In the diagnosis and treatment of noninflammatory conductive hearing loss in children, the combination of detailed medical history, specialized examination and imaging examination can maximize the accuracy of diagnosis and achieve the purpose of personalized comprehensive treatment. Surgical intervention with appropriate timing is important to remove lesions and improve hearing.

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.

Juvenile otosclerosis and congenital stapes footplate fixation. A systematic review and meta-analysis of surgical outcomes and management.

OBJECTIVE: Juvenile Otosclerosis (JO) and Congenital Stapes Footplate Fixation (CSFF) are rare ossicular chain disorders seen in the paediatric population and present with conductive hearing loss. Ongoing controversy exists regarding the role of surgical intervention in JO and CSFF given the poorer hearing outcomes and complications when compared with surgical intervention for adult otosclerosis. The objective of this study is to assess the published data on the surgical outcomes of JO and CSFF in order to guide clinicians and counsel patients on the various medical options for these disease entities. METHODS: A systematic review of MEDLINE, EMBASE and Cochrane was performed with inclusion criteria of children with JO or CSFF and hearing outcomes following stapes surgery. Studies identified by the search were reviewed and assessed by two independent reviewers in line with the PRISMA guidelines. RESULTS: 464 articles were initially reviewed and 28 articles met inclusion in the systematic review and meta-analysis. A total of 810 ears (473 and 337 cases of JO and CSFF respectively) underwent stapes surgery. Average age at time of surgery for JO and CSFF was 14.3 and 10.2 years old respectively. The mean pre-operative Air-Bone-Gap (ABG) for JO and CSFF was 31.8 ± 5.2 dB and 39.4 ± 10 dB respectively. Following stapes surgery, the mean post-operative ABG for JO and CSFF was 9.6 ± 6 dB and 19.2 ± 12.5 dB respectively. Surgical success rate (defined as ABG <10 dB) was 81% for JO and 41% for CSFF. Mean ABG gain for JO and CSFF was 24.8 dB (95% CI: 18.6-33.1) and 22.6 dB (95% CI: 18.4-27.8) respectively. The reported number of dead ears was 4/473 (0.8%) for JO and 2/337 (0.6%) for CSFF. 23 cases (2.8%) reported sensorineural hearing loss (SNHL) >10 dB. CONCLUSION: CSFF was associated with poorer hearing outcomes compared to JO, however both entities showed similar improvement in ABG post operatively. Counselling patients and their families on the surgical success rates and complications of JO or CSFF is an important part of the decision making process when deciding between a surgical option or conservative measures such as hearing aids.

A Partial Ossicular Replacement Prosthesis With a Concentric Ball Joint in the Headplate.

OBJECTIVE: In passive middle ear prosthetics, rigid implants have proven successful in reconstructing the ossicular chain. However, these cannot fully replicate the physiology of the ossicular chain. Pressure fluctuations cause high stresses in rigid passive prostheses, which can result in dislocation, protrusion, and pre-tension in the annular ligament resulting in unsatisfactory hearing results. METHODS: In collaboration with MED-EL, we developed a new passive middle ear prosthesis that features a balanced, centered ball joint between the headplate and shaft of the prosthesis. We compared the sound transmission properties of this new prosthesis with those of a standard rigid prosthesis. Using Laser-Doppler-Vibrometry, we measured the sound-induced velocity of the stapes footplate relative to a given acoustic stimulus. RESULTS: The new prosthesis showed equivalent sound transmission characteristics compared to the rigid prosthesis, whereas retaining the ability to compensate for pressure fluctuations due to its ball joint. This ensures good transmission properties even during displacements of the tympanic membrane. CONCLUSION: This development is a further step toward a physiological reconstruction of the ossicular chain. LEVEL OF EVIDENCE: NA Laryngoscope, 133:1717-1721, 2023.