The Merits of Bilateral Application of Middle Ear Implants in Patients With Bilateral Conductive and/or Mixed Hearing Loss.

This study investigated sound localization abilities in patients with bilateral conductive and/or mixed hearing loss (BCHL) when listening with either one or two middle ear implants (MEIs). Sound localization was measured by asking patients to point as quickly and accurately as possible with a head-mounted LED in the perceived sound direction. Loudspeakers, positioned around the listener within a range of +73°/-73° in the horizontal plane, were not visible to the patients. Broadband (500 Hz-20 kHz) noise bursts (150 ms), roved over a 20-dB range in 10 dB steps was presented. MEIs stimulate the ipsilateral cochlea only and therefore the localization response was not affected by crosstalk. Sound localization was better with bilateral MEIs compared with the unilateral left and unilateral right conditions. Good sound localization performance was found in the bilaterally aided hearing condition in four patients. In two patients, localization abilities equaled normal hearing performance. Interestingly, in the unaided condition, when both devices were turned off, subjects could still localize the stimuli presented at the highest sound level. Comparison with data of patients implanted bilaterally with bone-conduction devices, demonstrated that localization abilities with MEIs were superior. The measurements demonstrate that patients with BCHL, using remnant binaural cues in the unaided condition, are able to process binaural cues when listening with bilateral MEIs. We conclude that implantation with two MEIs, each stimulating only the ipsilateral cochlea, without crosstalk to the contralateral cochlea, can result in good sound localization abilities, and that this topic needs further investigation.

Comparison of Outcomes with the Use of Different Heat-Activated Crimping Prostheses in Stapedotomy.

OBJECTIVE: To determine differences in failure rate and hearing outcomes of a completely encircling heat-activated crimping prosthesis (SMart 360°) compared to partially encircling prosthesis (SMart). STUDY DESIGN: Retrospective chart review. SETTING: Private neurotology tertiary referral center. PATIENTS: Patients who underwent stapedotomies performed by the senior authors from 2008 to 2019 using the SMart prosthesis and SMart 360° prothesis. INTERVENTIONS: Stapedotomy operations with placement of a SMart or SMart 360° prosthesis. MAIN OUTCOME MEASURES: Incidence of early failure requiring revision surgery. Differences in preoperative air-bone gap (ABG) compared to postoperative ABG at 3 months, 1 year, and 2 years after surgery. RESULTS: A total of 228 stapedotomies were performed (SMart n = 48 and SMart 360° n = 180). Mean preoperative ABG for SMart and SMart 360° were 26.15 and 29 dB, respectively. The mean difference in ABG for the SMart at 3 months, 1 year, and 2 years were 17, 18, and 11 dB, respectively. The mean difference in ABG for the SMart 360° at 3 months, 1 year, and 2 years were 20, 20, and 19 dB. ABG differences at 3 months (p = 0.10) and 1 year (p = 0.36) were not statistically different. The failure rate for the SMart prosthesis was 12.5% and for the SMart 360° 2.2% (p = 0.002). CONCLUSIONS: There were no statistically significant differences in ABG changes for SMart compared to SMart 360°. The Smart 360 corrects the problem with early failure seen with the Smart prosthesis. PROFESSIONAL PRACTICE GAP AND EDUCATIONAL NEED: Determination of most efficacious stapes prosthesis. LEARNING OBJECTIVE: Which stapes prosthesis produces better hearing results with fewer failures. DESIRED RESULT: To disseminate information necessary to choose the best stapes prosthesis for patients. LEVEL OF EVIDENCE: Level III. INDICATE IRB OR IACUC: 2022-029-agh.

Comparing the Quality of Life and Hearing Thresholds Following Stapedectomy Versus Laser Stapedotomy with NiTiBOND Piston.

The purpose of this study was to examine the quality of life (QoL) and hearing thresholds of patients who underwent 2 types of stapes surgery. A retrospective cohort study was performed comparing stapedotomy with NiTiBOND prostheses (n=20) and stapedectomy with autogenous cortical bone columella (n=20), applying the Glasgow Benefit Inventory (GBI) and the Hearing Handicap Inventory for Adults outcome measures with hearing thresholds. Univariate comparative statistical methods were applied. The stapedotomy cohort had significantly better values of Social Support Score of the GBI as compared to the stapedectomy cohort (P=.016). No statistically significant difference was detected between the groups in the pre- and postoperative audiological results and the further QoL measures. Apart from the excellent postoperative audiological results of the different types of stapes surgeries, stapedotomy with NiTiBOND prostheses seems to be superior as regards QoL over stapedectomy applying autogenous cortical bone columella.

Hearing Outcomes After Ossiculoplasty With Bone or Titanium Prostheses-A Nationwide Register-Based Study.

OBJECTIVES: This study compares hearing outcomes of two prosthesis materials, bone and titanium, used in ossiculoplasty. DESIGN: This retrospective nationwide registry-based study uses data systematically collected by the Swedish Quality Registry for Ear Surgery (SwedEar). SETTING: The data were obtained from clinics in Sweden that perform ossiculoplasty. PARTICIPANTS: Patients who underwent ossiculoplasty using either bone or titanium prostheses were registered in SwedEar between 2013 and 2019. MAIN OUTCOME MEASURES: Hearing outcome expressed as air-bone gap (ABG) gain. RESULTS: The study found no differences between bone and titanium for ABG or air conduction (AC) for either partial ossicular replacement prostheses (PORP) or total ossicular replacement prostheses (TORP). In a comparison between PORP and TORP for ABG and AC outcomes, regardless of the material used, PORP showed a small advantage, with an additional improvement of 3.3 dB (95% CI [confidence interval], 0.1-4.4) in ABG and 2.2 dB (95% CI, 1.7-4.8) in AC. In secondary surgery using TORP, titanium produced slightly better results for high-frequency pure tone average. The success rate, a postoperative ABG ≤20 dB, was achieved in 62% of the operations for the whole group. CONCLUSION: Both bone and titanium used to reconstruct the ossicular chain produce similar hearing outcomes for both PORP and TORP procedures. However, titanium may be a preferable option for secondary surgeries involving TORP. The success rate, a postoperative ABG ≤20 dB, is consistent with other studies, but there is room for improvement in patient selection criteria and surgical techniques.

The New Semisynthetic TORP: A Prosthesis for Ossicular Reconstruction Both With the Absence and the Presence of the Stapes Superstructure.

OBJECTIVES: To describe the new semisynthetic total ossicular replacement prosthesis (New-SSTORP) and to evaluate the New-SSTORP ossiculoplasty results both with the presence and absence of the stapes superstructure. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. METHODS: From April 2023 to May 2023, 18 New-SSTORP ossiculoplasties were performed by the first author. In all patients, the New-SSTORP was interposed between the footplate and the eardrum. The study group was divided into two groups (group A and group B). Group A included 13 patients with the absence of stapes superstructure. Group B included five patients with the presence of stapes superstructure. A successful reconstruction was defined as a postoperative air-bone gap ABG ≤20 dB. For all patients of groups A and B, the last audiometric control considered was performed in January 2024. The mean follow-up was 8½ months. The χ2 test was used to compare results. p < 0.05 was considered significant. MAIN OUTCOME MEASURES: Mean postoperative ABG ≤20 dB. RESULTS: At the end of follow-up, the overall success rate (ABG ≤20 dB) of New-SSTORP ossiculoplasty was obtained in 88.8% (n = 16 of 18) of cases. In group A, the success rate of New-SSTORP ossiculoplasty occurred in 84.6% (n = 11 of 13) of cases, and in group B, the success rate of New-SSTORP ossiculoplasty occurred in 100% (n = 5 of 5) of cases. There was no audiological statistically significant difference between groups A and B (Fisher value is 1; p < 0.05). In all cases, the time for positioning of New-SSTORP was about 5 minutes. CONCLUSION: The New-SSTORP has a minimal technical challenge for building and placement. The New-SSTORP ossiculoplasty results are very good both with the presence and absence of SS.

Integration of 3D-printed middle ear models and middle ear prostheses in otosurgical training.

BACKGROUND: In otosurgical training, cadaveric temporal bones are primarily used to provide a realistic tactile experience. However, using cadaveric temporal bones is challenging due to their limited availability, high cost, and potential for infection. Utilizing current three-dimensional (3D) technologies could overcome the limitations associated with cadaveric bones. This study focused on how a 3D-printed middle ear model can be used in otosurgical training. METHODS: A cadaveric temporal bone was imaged using microcomputed tomography (micro-CT) to generate a 3D model of the middle ear. The final model was printed from transparent photopolymers using a laser-based 3D printer (vat photopolymerization), yielding a 3D-printed phantom of the external ear canal and middle ear. The feasibility of this phantom for otosurgical training was evaluated through an ossiculoplasty simulation involving ten otosurgeons and ten otolaryngology-head and neck surgery (ORL-HNS) residents. The participants were tasked with drilling, scooping, and placing a 3D-printed partial ossicular replacement prosthesis (PORP). Following the simulation, a questionnaire was used to collect the participants' opinions and feedback. RESULTS: A transparent photopolymer was deemed suitable for both the middle ear phantom and PORP. The printing procedure was precise, and the anatomical landmarks were recognizable. Based on the evaluations, the phantom had realistic maneuverability, although the haptic feedback during drilling and scooping received some criticism from ORL-HNS residents. Both otosurgeons and ORL-HNS residents were optimistic about the application of these 3D-printed models as training tools. CONCLUSIONS: The 3D-printed middle ear phantom and PORP used in this study can be used for low-threshold training in the future. The integration of 3D-printed models in conventional otosurgical training holds significant promise.

Long-term outcomes following pediatric endoscopic titanium ossiculoplasty: A single-institution experience.

INTRODUCTION: Endoscopic ossicular chain reconstruction (OCR) in adults has demonstrated equivalent outcomes to the traditional microscopic approach. Less data exist on endoscopic OCR outcomes in children, who have unique considerations including a smaller transcanal corridor and variable pathology. The purpose of this study was to investigate surgical and audiometric outcomes in children undergoing fully endoscopic and endoscopic-assisted OCR in both the short and long-term. METHODS: Retrospective review of all children (<17 years) who underwent endoscopic OCR at one tertiary care center between 2017 and 2021. Children undergoing primary and revision endoscopic OCR with either partial (PORP) and total ossicular reconstruction prostheses (TORP) were included. Children undergoing surgery for juvenile otosclerosis or congenital stapes fixation, or any child receiving a stapes prosthesis were excluded. Primary outcome measures were post-operative change in 4 frequency (500 Hz, 1, 2, 4 KHz) air conduction pure tone average (AC PTA) and change in air-bone gap (ABG). Secondary measures included need for readmission and/or revision surgery, complication rate, and surgery duration. RESULTS: Seventeen patients met inclusion criteria. Average age was 11.3 years (range, 5-17 years); 14 were male. A variety of fixed length, titanium total and partial prostheses were used. The most common prosthesis length was 2 mm (range 2-5 mm), and there were no intra- or perioperative complications. Mean long-term follow-up was 2.6 years. Most common pathology was congenital cholesteatoma (11/17, 64%), followed by chronic otitis media with tympanic membrane perforation (5/17, 29.4%), and extruded prosthesis (1/17, 5.9%). Intraoperatively, the most common finding was incus erosion (10/17, 58.8%), followed by malleus erosion (6/17, 35.3%), stapes erosion (4/17, 23.5%), and stapes absence (4/17, 23.5%). Eight children (47%) were reconstructed with PORPs, and 9 children (52.9%) were reconstructed with TORPs. Average ABG improved from 36.8 dB preoperatively to 19.9 dB postoperatively in the short-term and remained stable at 19.5 dB in the long-term. Average short-term ABG improvement was 4.2 dB for PORPs and 18 dB for TORPs. In the long-term, average ABG improved by 2.3 dB in PORPs and 13.4 dB in TORPs. PORPs had higher rates of ABG closure and lower AC PTAs than TORPs in the long-term. DISCUSSION: Endoscopic ossiculoplasty is a viable option in children presenting with ossicular erosion from various causes. Audiometric improvement following endoscopic partial and total ossicular reconstruction remains stable over time, with a preference towards partial in the long-term, and mirrors published outcomes for microscopic surgery.

Ultra-high-resolution CT of the temporal bone: The end of stapes prosthesis dimensional error and correlation with patient symptoms.

PURPOSE: To describe the reliability of ultra-high-resolution computed tomography (UHR-CT) in the measurement of titanium stapes prostheses using manufacturer data as a reference. MATERIALS AND METHODS: This retrospective study included patients treated by stapedectomy with titanium prostheses who underwent UHR-CT between January 2020 and October 2023. Images were acquired using an ultra-high-resolution mode (slice thickness: 0.25 mm; matrix, 1024 × 1024). Two radiologists independently evaluated the length, diameter, and intra-vestibular protrusion of the prosthesis. Post-operative air-bone gaps (ABGs) were recorded. RESULTS: Fourteen patients were enrolled (mean age, 44.3 ± 13.8 [SD] years, 9 females), resulting in 16 temporal bone UHR-CTs. The exact length was obtained in 81.3 % (n = 13/16) and underestimated by 0.1 to 0.3 mm in the remaining 18.7 % (n = 3/16) CT scans for both readers (mean misestimation: -0.02 ± 0.06 [SD] mm, overall underestimation of 0.43 %). The exact diameter was reported in 75 % (n = 12/16) and 87.5 % (n = 14/16) of the CT scans for readers 1 and 2, respectively, and was off by 0.1 mm in all discrepancies (mean misestimation: 0.01 ± 0.04 [SD] mm, overall overestimation of 2.43 %). Intravestibular prosthesis protrusion was of 0.5 ± 0.43 [SD] mm (range: 0-1) and 0.49 ± 0.44 [SD] mm (range: 0-1.1) for readers 1 and 2, respectively, and did not correlate with ABGs (r = 0.25 and 0.22; P = 0.39 and 0.47 for readers 1 and 2, respectively). Intra and interobserver agreements were excellent. CONCLUSION: UHR-CT provides 99.6 % and 97.6 % accuracy for prosthesis length and diameter measurements, respectively.

Adverse events associated with Vibrant Soundbridge: A MAUDE study.

OBJECTIVE: To summarize adverse events and their root causes reported to the United States Food and Drug Administration (FDA) on Vibrant Soundbridge (VSB) hearing device (Med-El, Innsbruck, Austria), an active middle ear implant for patients with moderate to severe hearing loss. MATERIALS AND METHODS: The FDA's Manufacturer and User Facility Device Experience (MAUDE) database was queried for reports of VSB adverse events from January 1, 2012, to July 27, 2022. RESULTS: Six hundred sixty-three total medical device reports were identified, from which 913 adverse events were extracted. Of these, 498 (54.5 %) were adverse events to patients (AEPs), while 415 (45.5 %) were device malfunctions (DMs). The most common AEPs were hearing performance issues 428 (85.9 %). The most common DMs were compromised conductive link 125 (30.1 %). Root causes identified for DMs were iatrogenic 85 (58.6 %), patient-related 28 (19.3 %), and trauma and external causes 32 (22.1 %). The most common iatrogenic root cause 12 (14.1 %) involved damage to the conductive link during revision surgery. The most common patient-related causes of DMs were excessive middle ear tissue growth 16 (57 %), and abrupt body movements 5 (28.6 %). The most common external cause of DM was cleaning of the ear canal or mastoid cavity 20 (62.5 %). CONCLUSIONS: Despite its well-known limitations, the MAUDE database provides valuable information on possible complications of VSB as it relates to device malfunction or adverse events for patients. Implementation of standardized reports with relevant and well-defined categories could certainly allow for a more meaningful analysis.

Analysis of the effect of reconstructing the ossicular chain under otoendoscopy with and without a stapes superstructure.

BACKGROUND: Numerous studies have been conducted on the effect of the stapes superstructure after ossicular chain reconstruction, but the findings are not uniform. OBJECTIVE: To compare the hearing outcomes of ossicular chain reconstruction with partial ossicular replacement prosthesis (PORP) or total ossicular replacement prosthesis (TORP) under otoendoscopy. MATERIALS AND METHODS: The records of 111 patients diagnosed with chronic suppurative otitis media were retrospectively analyzed. These patients were divided into PORP group (n = 57) and TORP group (n = 54). They were further subdivided into subgroups PORP-a (with a malleus handle) and PORP-b (without a malleus handle), subgroups TORP-a and TORP-b. Pre- and postoperative audiometric results were analyzed. RESULTS: The mean postoperative air conduction hearing thresholds improvement, mean air-bone gap improvement, and the success rate of reconstruction were significantly higher in the PORP group than in the TORP group (p < .05). The mean postoperative air conduction hearing thresholds improvement and the success rate of reconstruction were significantly higher in the PORP-a group than in the TORP-a group (p < .05); and similar results were concluded in comparison of the PORP-b group and the TORP-b group. CONCLUSIONS AND SIGNIFICANCE: The stapes superstructure has an important positive effect on the postoperative outcome of endoscopic ossicular chain reconstruction.

MRI Safety of Stapes Prostheses: A Systematic Review.

OBJECTIVE: To assess magnetic resonance imaging (MRI) safety of stapes prostheses. DATA SOURCES: Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases were searched from inception to November 2021 following PRISMA guidelines. REVIEW METHODS: Studies reporting evidence of stapes prosthesis displacement or interaction in adult or pediatric implant recipients undergoing MRI. Cadaveric, animal, and basic studies with nonhuman data were also included. RESULTS: From an initial search of 123 articles, 42 full-text studies were evaluated for eligibility and 19 studies that met the inclusion criteria were included. Motion artifact was reported in a few stainless steel prosthesis types in vitro; however, such displacement was not observed in human cadaver temporal bone studies and had no adverse reported outcomes. A small subgroup of patients in the 1980s received a ferromagnetic stainless steel stapes implant that was recalled and has not been used since 1987. Patients with implants performed in the 1980s should be directed to 1.5T scanners from an abundance of caution. CONCLUSION: Modern (post-1987) stapes prostheses do not pose a risk in vivo when exposed to the magnetic fields of MRI scanners.

Congenital Absence of Stapes Suprastructure and Footplate: A Case Report.

INTRODUCTION: Congenital ossicular chain anomalies are rare conductive hearing loss conditions that remain difficult to diagnose even with high-resolution computed tomography (CT). The preoperative diagnosis is helpful for surgical planning and counseling patients regarding treatment outcomes. CASE PRESENTATION: We report a case involving a 14-year-old boy presenting with left conductive hearing loss without history of trauma for 5 years, physical examination showed normal otoscopic examination bilaterally and high-resolution CT showed absent of stapes suprastructure and footplate. Subsequent diagnosis was done via endoscopic middle ear exploration which revealed an absent long process of the incus, stapes suprastructure and footplate, but with intact oval window membrane. The residual incus was removed, and a tragal perichondrium graft was used over the oval window. A total ossicular replacement prosthesis was placed between the malleus and oval window to repair the chain. Postoperatively, the patient had no complications. Preoperative pure tone average revealed an air/bone result of 52/8 dB. Follow-up after surgery at 6 months showed a pure tone average air/bone result of 15/3 dB. The air-bone gap was reduced from 44 to 12 dB. CONCLUSION: Congenital absence of the stapes suprastructure and footplate remains a rare condition compared to the myriad of middle ear anomalies in the literature.

The TORP-PORP: A Tympanoplasty Technique for Isolated Defects of the Stapes Suprastructure.

OBJECTIVE: Investigating the outcomes of a surgical approach to treat isolated defects of the stapes suprastructure, using a modified total ossicular replacement prosthesis (TORP) prosthesis as a PORP between the footplate and the incus, effectively creating a TORP-PORP configuration. PATIENTS: Eleven patients (mean age, 37.2 years; 36% male and 64% female) between the years 2007 and 2022. INTERVENTIONS: Therapeutic (ossiculoplasty). MAIN OUTCOME MEASURES: Hearing gain (in dB) in air conduction thresholds at 0.5, 1, 2, 3, and 4 kHz, stability of bone conduction, revision rate. RESULTS: Significant improvement in air conduction between the preoperative and the postoperative cohorts (p = 0.002) with a mean postoperative hearing level of 30.00 ± 5.25 dB. The bone conduction remained stable. We encountered no perioperative complications, and there were no revisions surgery. CONCLUSIONS: The described ossiculoplasty procedure is a safe and effective approach to treat isolated defects of the stapes suprastructure.

Techniques of Endoscopic Ossiculoplasty.

The utilization of endoscopes in modern otology has evolved from diagnostic purposes to the development of exclusive endoscopic ear surgery. This technique offers a panoramic view of the middle ear and provides an optimal magnification of the oval window region, the stapes' suprastructure, and the footplate, allowing great precision in prosthesis positioning during ossiculoplasty (OPL). Various techniques for ossicular chain reconstruction have been described in the literature. Either autologous or synthetic materials can be used for reconstruction. The use of a patient's own tissue minimizes the risk of implant rejection or extrusion of the prosthesis through the tympanic membrane. On the other hand, synthetic materials like titanium are light and rigid and do not require time-consuming prosthesis remodeling. The main objective of this article is to present a comprehensive step-by-step guide that serves as a surgical manual for exclusive endoscopic OPL. This guide will explain various forms of OPL using synthetic and autologous materials. The goal is to provide a comprehensive understanding of the various surgical techniques and support the integration into clinical practice.

Bone cement in ossicular chain reconstruction: systematic review and meta-analysis.

OBJECTIVES: To compare the hearing outcomes of ossicular chain reconstruction using bone cement versus other materials such as prostheses and autografts. METHODS: This study included articles that compared hearing outcomes in patients with conductive hearing loss who underwent stapes revision surgery or chronic otitis media surgery. A systematic search for articles from January 2000 to February 2022 was conducted in Medline, Embase, and Cochrane Library databases. Only articles in English were included. An effective postoperative air-bone gap (ABG) was defined as ≤20 dB. A bias assessment tool was developed according to Cochrane guidelines, and the chi-square test was used to evaluate the mean age of the samples. RESULTS: Of the 418 studies that met the selection criteria, only seven were eligible for this study, consisting of 187 patients in the bone cement group and 173 in the non-bone cement group. Ossiculoplasty using bone cement yielded significantly better results, with a combined odds ratio (OR) of 2.03 (95% CI: 1.16-3.55, p = 0.01). CONCLUSIONS: The results of this study suggest that the effectiveness of bone cement in ossiculoplasty was greater than that of other materials in chronic otitis media surgery or stapes revision surgery, with a higher number of patients achieving ABG ≤20 dB.

Comparison of hearing performance in patients with borderline indication for active middle ear or cochlear implants: clinical outcomes to guide preoperative counseling and decision making.

PURPOSE: The aim of the presented study was to compare the audiological benefit achieved in cochlear implant (CI) patients who, in principle, could still have been treated with an active middle ear implant (AMEI) with a group of AMEI users. METHODS: Results of 20 CI patients with a pure-tone average (PTA) of 70 dB HL prior to surgery were compared with a group of 12 subjects treated with a Vibrant Soundbridge (VSB). Pre-surgical comparison included PTA for air conduction and bone conduction, maximum speech recognition score for monosyllabic words (WRSmax), and aided monosyllabic word recognition at 65 dB SPL. One year after surgery, aided monosyllabic speech recognition score at 65 dB SPL was compared. RESULTS: Mean PTA for air conduction in the VSB group was significantly lower than in the CI group (4.8 dB, Z = - 2.011, p < 0.05). Mean PTA for bone conduction in the VSB group was also significantly lower than in the CI group (23.4 dB, Z = - 4.673, p < 0.001). WRSmax in the VSB group was significantly better than in the CI group (40.7%, Z = - 3.705, p < 0.001). One year after treatment, there was no significant difference in aided speech perception in quiet between both subject groups. CONCLUSION: Comparison of the two methods showed equivalent results for both treatments in subjects with a borderline indication. Not only pure-tone audiometry results but, particularly, speech perception scores pre-surgery should be taken into account in preoperative counseling.

The effect of piston diameter in primary stapes surgery on surgical success.

PURPOSE: To evaluate the effect of piston diameter in patients undergoing primary stapes surgery on audiometric results and postoperative complications. METHODS: A retrospective single-center cohort study was performed. Adult patients who underwent primary stapes surgery between January 2013 and April 2022 and received a 0.4-mm-diameter piston or a 0.6-mm-diameter piston were included. The primary and secondary outcomes were pre- and postoperative pure-tone audiometry, pre- and postoperative speech audiometry, postoperative complications, intraoperative anatomical difficulties, and the need for revision stapes surgery. The pure-tone audiometry included air conduction, bone conduction, and air-bone gap averaged over 0.5, 1, 2 and 3 kHz. RESULTS: In total, 280 otosclerosis patients who underwent 321 primary stapes surgeries were included. The audiometric outcomes were significantly better in the 0.6 mm group compared to the 0.4 mm group in terms of gain in air conduction (median = 24 and 20 dB, respectively), postoperative air-bone gap (median = 7.5 and 9.4 dB, respectively), gain in air-bone gap (median = 20.0 and 18.1 dB, respectively), air-bone gap closure to 10 dB or less (75% and 59%, respectively) and 100% speech reception (median = 75 and 80 dB, respectively). We found no statistically significant difference in postoperative dizziness, postoperative complications and the need for revision stapes surgery between the 0.4 and 0.6 mm group. The incidence of anatomical difficulties was higher in the 0.4 mm group. CONCLUSION: The use of a 0.6-mm-diameter piston during stapes surgery seems to provide better audiometric results compared to a 0.4-mm-diameter piston, and should be the preferred piston size in otosclerosis surgery. We found no statistically significant difference in postoperative complications between the 0.4- and 0.6-mm-diameter piston. Based on the results, we recommend always using a 0.6-mm-diameter piston during primary stapes surgery unless anatomical difficulties do not allow it.

Performance of personalised prosthesis under static pressure: Numerical analysis and experimental validation.

This study investigates the performance of personalised middle ear prostheses under static pressure through a combined approach of numerical analysis and experimental validation. The sound transmission performances of both normal and reconstructed middle ears undergo changes under high positive or negative pressure within the middle ear cavity. This pressure fluctuation has the potential to result in prosthesis displacement/extrusion in patients. To optimise the design of middle ear prostheses, it is crucial to consider various factors, including the condition of the middle ear cavity in which the prosthesis is placed. The integration of computational modelling techniques with non-invasive imaging modalities has demonstrated significant promise and distinct prospects in middle ear surgery. In this study, we assessed the efficacy of Finite Element (FE) analysis in modelling the responses of both normal and reconstructed middle ears to elevated static pressure within the ear canal. The FE model underwent validation using experimental data derived from human cadaveric temporal bones before progressing to subsequent investigations. Afterwards, we assessed stapes and umbo displacements in the reconstructed middle ear under static pressure, with either a columella-type prosthesis or a prosthetic incus, closely resembling a healthy incus. Results indicated the superior performance of the prosthetic incus in terms of both sound transmission to the inner ear and stress distribution patterns on the TM, potentially lowering the risk of prosthesis displacement/extrusion. This study underscores the potential of computational analysis in middle ear surgery, encompassing aspects such as prosthesis design, predicting outcomes in ossicular chain reconstruction (OCR), and mitigating experimental costs.