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.

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.

Primary ossiculoplasties provide better hearing results than revisions: a retrospective cohort study.

PURPOSE: To evaluate the efficacy of ossicular chain reconstruction (OCR) in primary and revision surgeries, and to investigate the impact of the number of previous surgeries on hearing outcomes. METHODS: Retrospective analysis of cases with OCR due to chronic otitis in a tertiary center between January 2018 and September 2021. RESULTS: Altogether, 147 cases of ossicle involvement were assessed. In 91.83% (n = 135) OCR was performed, 96.26% of them with titanium TORP/PORP (n = 130), two cases with autologous prosthesis and three with piston. Mean follow-up was 8.8 months. The ABG significantly improved in the total group (TORP/PORP) from a mean (SD) of 30.94 (15.55) to 19.76 (13.36) dB (p < 0.0001) with 60.86% success. The best results were achieved in primary OCR with PORP implantation without cholesteatoma (89.47%). Primary cases have a significantly higher success rate in contrary to revision surgeries (72.27%, vs. 52.00%, p = 0.032). The only relevant predictive factor proved to be the fact of revision (p = 0.029). A statistically significant correlation between the number of previous surgeries and hearing results could not be proved. There was no difference in hearing outcomes between patients with only one or more than one previous surgeries in the revision groups. Neither the presence of cholesteatoma, nor the type of OCR (TOPR/PORP) and the indication of revision had an impact on postoperative ABG. CONCLUSIONS: Titanium prostheses are effective in OCR both in primary and revision cases. It is not the number of previous surgeries, but the fact of revision that influences postoperative hearing results.

Can the unmodified incus be used for a simpler, more cost-effective functional ossicular chain reconstruction? A retrospective clinical study.

OBJECTIVE: To evaluate patients' hearing outcomes after ossicular chain reconstruction using unmodified autologous incus. METHODS: A single-centred, retrospective study of patients who underwent incus interposition between June 2010 and October 2017 was conducted at a Dutch secondary referral centre. This paper describes a chart review of patients who presented with erosion of the long process of the incus due to atelectasis or cholesteatoma who were treated with an unmodified incus interposition. The main outcome measures were: post-operative air-bone gap and level of air-bone gap closure. RESULTS: Thirty-three ears of 32 patients were included. Follow-up duration ranged from six weeks to seven years. A mean post-operative air-bone gap under 25 dB was considered successful; this was achieved in 25 patients (76 per cent), 20 (91 per cent) in the partial ossicular reconstruction prosthesis group and 5 (45 per cent) in the total ossicular reconstruction prosthesis group. This difference was statistically significant (p = 0.007). CONCLUSION: Successful preservation and improvement of hearing was observed in most patients. As expected, the closure rate in the partial ossicular reconstruction prosthesis group was better. Longer follow-up studies with larger case numbers are needed to assess whether further reconstruction techniques are necessary.

PORP vs. TORP in children: A systematic review and meta-analysis.

OBJECTIVES: To compare the mean pre-operative air-bone gaps (ABG), mean post-operative ABGs, and extrusion rates between pediatric recipients of partial ossicular reconstruction prostheses (PORPs) and pediatric recipients of total ossicular reconstruction prostheses (TORPs) via a systematic review and meta-analysis. METHODS: A quantitative systematic review last updated on September 29, 2021 of PubMed, Scopus, and Embase databases was conducted for studies reporting mean post-operative ABGs or numbers of children with post-operative ABG ≤ 20 dB following PORP and TORP procedures in at least five children aged 0-18 years. Studies were excluded if they were review articles, conference abstracts, or not in English. Studies that primarily reported data on congenital aural atresia, stapedectomy/stapedotomy, congenital stapes fixation, or juvenile otosclerosis were also excluded. NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to assess for risk of bias. Review Manager (RevMan) version 5.4.1 was used to perform the meta-analysis and generate forest plots. RESULTS: Out of 648 unique abstracts retrieved, 11 papers were included in this systematic review with meta-analysis. Data from 449 children (247 TORP recipients and 202 TORP recipients) are represented among the various analyses. Data from nine studies, representing 84.2 % of all children in the systematic review, demonstrated that PORP recipients presented with a pre-operative ABG 6.30 dB less than TORP recipients (mean difference: -6.30, 95 %CI: -7.4, -5.18, p < 0.01). Data from these same children demonstrated that PORP recipients had a 1.80 dB less post-operative ABG compared to TORP recipients (mean difference: -1.80 dB, 95 %CI: -2.84, -0.77, p < 0.001). Data from seven studies, representing 49.4 % of all children in the systematic review, demonstrated that PORP recipients were more likely to have a successful closure of the post-operative ABG to ≤20 dB (OR: 2.12, 95 %CI: 1.18, 3.79, p = 0.01). In these same children, 62.5 % of PORP recipients had a post-operative ABG ≤ 20 dB and 48.3 % of TORP recipients had a post-operative ABG ≤ 20 dB. There was no difference in extrusion rates between PORP recipients compared to TORP recipients (OR: 1.08, 95 %CI: 0.31, 3.78, p = 0.90) from five studies representing 45.9 % children in the systematic review. CONCLUSION: Children who receive a PORP have better pre-operative hearing baselines and post-operative hearing outcomes compared to those who receive TORP with similar rates of extrusion. More pediatric studies should report their mean pre- and post-operative ABGs stratifying by various material types, surgical indications, and surgical details to facilitate future meta-analyses.

FDA MAUDE database analysis of titanium middle ear prosthesis.

PURPOSE: Partial ossicular replacement (PORP) and total ossicular replacement prostheses (TORP) are used to restore ossicular chain function. Despite favorable auditory outcomes, these interventions have associated risks and complications. This study examines the FDA MAUDE database for ossicular chain prosthesis adverse events to highlight complications, interventions, and root cause analysis (RCA) findings. MATERIALS AND METHODS: The MAUDE database was searched for Medical Device Reports (MDRs) relating to PORPs and TORPs from 2010 to 2020. MDR event descriptions were reviewed, and adverse events were identified as a device issue, patient issue, and/or packaging issue that occurred intraoperatively or postoperatively. RESULTS: Our search identified 70 MDRs which included 110 reported adverse events. Events consisted of 63 device issues, often due to device breaks and displacements, 39 patient issues, including common complaints of hearing loss and erosion, and 8 packaging issues. When comparing PORPs and TORPs, TORPs had more reported device issues whereas PORPs had more packaging issues. Intraoperative device issues were commonly resolved by completing the procedure with a backup device and most postoperative device issues required additional surgery. For devices returned to the manufacturer, RCA determined that most breaks were caused by modification and/or mishandling or that the product met specifications with an undetermined cause for the break. CONCLUSION: Device issues were the most common adverse events and frequently required subsequent intervention. Displacement occurred more often with TORPs and was associated with changes in hearing or erosion. The findings of this study are purely descriptive and may not have direct clinical relevance.

Incus Autograft Partial Ossicular Reconstruction Prosthesis vs. Titanium Angular Clip Prosthesis in Patients with Incudostapedial Joint Erosion Caused by Chronic Otitis Media; A Randomized Clinical Trial.

Chronic otitis media (COM) is a common disease that can cause damage to the middle ear ossicles and thus lead to conductive hearing loss. The purpose of this study was to compare two methods of incus partial ossicular reconstruction prosthesis (PORP) and reconstruction with titanium angular clip prosthesis in patients with incudostapedial joint erosion. In this interventional randomized clinical trial carried out in a tertiary referral hospital, patients with chronic otitis media and incudostapedial joint erosion who were candidates for surgery, were randomly allocated into two groups of incus PORP surgery and reconstruction with a titanium angular clip prosthesis. Audiometry was performed for the patients prior to and six months after surgery. Pre- and post-operative air-bone gap (ABG) and bone conduction (BC) thresholds were calculated and means were compared by analysis of variances (ANOVA). A P value of <0.05 was considered statistically significant. The study consisted of 24 and 14 subjects in the incus PORP and angular clip groups, respectively. There was no statistically significant difference between the mean pre- and post-operative ABG, BC thresholds and ABG reduction in the compared groups. Considering issues such as high cost and inaccessibility of titanium angular clips in all centers, incus PORP may be a more acceptable method.

Robot-Assisted Middle Ear Endoscopic Surgery: Preliminary Results on 37 Patients.

Background: Endoscopy during middle ear surgery is advantageous for better exploration of middle ear structures. However, using an endoscope has some weaknesses as surgical gestures are performed with one hand. This may trouble surgeons accustomed to using two-handed surgery, and may affect accuracy. A robot-based holder may combine the benefits from endoscopic exposure with a two-handed technique. The purpose of this study was to assess the safety and value of an endoscope held by a teleoperated system. Patients and Methods: A case series of 37 consecutive patients operated using endoscopic exposure with robot-based assistance was analyzed retrospectively. The RobOtol® system (Collin, France) was teleoperated as an endoscope holder in combination with a microscope. The following data were collected: patient characteristics, etiology, procedure type, complications, mean air and bone conduction thresholds, and speech performance at 3 months postoperatively. Patients had type I (myringoplasty), II (partial ossiculoplasty), and III (total ossiculoplasty) tympanoplasties in 15, 14, and 4 cases, respectively. Three patients had partial petrosectomies for cholesteatomas extending to the petrous apex. Finally, one case underwent resection of a tympanic paraganglioma. Ambulatory procedures were performed in 25 of the 37 patients (68%). Results: Complete healing with no perforation of the tympanic membrane was noted postoperatively in all patients. No complications relating to robotic manipulation occurred during surgery or postoperatively. The mean air conduction gain was 3.8 ± 12.6 dB for type I (n = 15), 7.9 ± 11.4 dB for type II (n = 14), and -0.9 ± 10.8 for type III tympanoplasties (n = 4), and the postoperative air-bone conduction gap was 13.8 ± 13.3 dB for type I, 19.7 ± 11.7 dB for type II and 31.6 ± 13.0 dB for type III tympanoplasty. They was no relapse of cholesteatoma or paraganglioma during the short follow-up period (<1 year). Conclusion: This study indicates that robot-assisted endoscopy is a safe and trustworthy tool for several categories of middle ear procedures. It combines the benefits of endoscopic exposure with a two-handed technique in middle ear surgery. It can be used as a standalone tool for pathology limited to the middle ear cleft or in combination with a microscope in lesions extending to the mastoid or petrous apex.

Comparative analysis of titanium clip prostheses for partial ossiculoplasty.

OBJECTIVES: The aim of our study was to perform a comparative analysis in our cases with titanium partial clip ossiculoplasty in terms of audiometric outcome and extrusion rates as well as to review the literature for relevant information on this surgical issue. MATERIALS AND METHODS: The records of all patients who had undergone primary partial ossiculoplasty with the implantation of a CliP® Partial Prosthesis Dresden Type (CPPDT, group A) or a CliP Partial FlexiBAL® (CPF, Group B, both Heinz Kurz GmbH, Dusslingen, Germany) between 2012 and 2020 were studied retrospectively. RESULTS: 274 patients made up our study sample (148 men, 126 women, male to female ratio: 1.17). Their mean age at the time of first surgery was 39.6 years (range: 4-79 years). The mean preoperative air-bone gap (ABG) was 22.7dΒ ± 10.5 dB. Mean follow-up was approximately 4 months (1-12 months). The mean postoperative ABG was 15.7 ± 8.1 dB. In total, the postoperative ABG was significantly improved compared to preoperative values (P < 0.001). Surgical success, defined as an ABG ≤ 20 dB, was achieved in the majority of our study patients (210/274, 76.6%). Extrusion of the prosthesis was detected in 3/216 CPF and 5/58 CPPDT cases (p = 0.012). Comparison of both prosthesis groups revealed a significantly better audiological outcome for the patients with ossicular reconstruction using CPF. A significantly better audiological outcome was detected in the cases with a normal aeration of the middle ear. DISCUSSION: Titanium clip partial ossiculoplasty is a reliable component of modern tympanoplasty, allowing a satisfying audiologic outcome. The higher adaptability of the CPF to the changing postoperative circumstances and the frequently defective aeration of the middle ear is reflected in the better audiologic outcome for this prosthesis.

The effect of using a PORP to reconstruct the ossicular chain under otoendoscopy with and without a malleus handle.

BACKGROUND: There are many reports on the role of the malleus handle in ossicular chain reconstruction (OCR). However, the effect of the presence of the malleus handle is not clear. AIM/OBJECTIVES: To compare the hearing outcomes of using a partial ossicular replacement prosthesis (PORP) to reconstruct the ossicular chain under otoendoscopy with and without a malleus handle. METHODS: Records of 57 patients requiring OCR were retrospectively analyzed. They were divided into the malleus handle-present group (group 1) and the malleus handle-absent group (group 2). The audiometric results were analyzed pre- and postoperatively. A postoperative air-bone gap (ABG)≤20 dB was considered successful. RESULTS: The mean improvement in air conduction hearing thresholds was 19.80 dB in group 1 and 16.70 dB in group 2. The mean ABG improvement was 18.09 ± 12.79 dB for group 1 and 17.20 ± 16.44 dB for group 2. The malleus handle-present group achieved higher success (65.63%) than the malleus handle-absent group (52%; p> .05). CONCLUSIONS AND SIGNIFICANCE: Improvements in hearing outcomes were similar for the two groups. However, the malleus handle-present group showed a better reconstruction success rate. Our results suggest that if there is no lesion in the malleus handle, it is recommended to be retained.

Comparison of total and partial ossicular replacement prostheses in patients with an intact stapes suprastructure.

OBJECTIVES: To compare the results of ossiculoplasty with two different partial ossicular replacement prostheses (PORP) to ossiculoplasty with a total ossicular replacement prosthesis (TORP) in patients with an intact stapes suprastructure. METHODS: All patients required primary or revision surgery for chronic middle ear disease and ossicular reconstruction with either a PORP or a TORP, as well as a with an intact stapes suprastructure. In total, 141 patients receiving classic tympanoplasty with PORP (N = 92), ossiculoplasty with PORP with ball joint (N = 22), or TORP (N = 27) between January 2011 and March 2017 were included in this study. The inclusion criterion was an intact stapes suprastructure. The underlying indication for surgery was either middle ear disease, such as cholesteatoma, or revision surgery for audiological improvement. The main outcome measures were four-frequency pure tone average (0.5, 1, 2, 3 kHz) at early and late follow-up after ossiculoplasty, the effects of clinical factors including the underlying middle ear disease, and primary or revision surgery. RESULTS: All patients showed a significantly reduced air-bone gap (ABG 0.5, 1, 2, 3 kHz) at late follow-up (mean: 18 dB) compared to preoperative measurements (mean: 25.5 dB). A significantly better outcome in ABG closure was shown among patients with a preoperatively intact tympanic membrane, with an intact stapes suprastructure or without preexisting cholesteatoma. Outcome was not significantly influenced by the prosthesis-type, the creation of an open mastoid cavity, the status of the mucosa, or the indication for surgery. CONCLUSION: TORP with an intact stapes suprastructure is a safe procedure and provides audiological outcomes similar to PORP. LEVEL OF EVIDENCE: 2C Laryngoscope, 130:768-775, 2020.

Comparison of the application of artificial ossicles and autologous ossicles in the reconstruction of a damaged ossicular chain.

OBJECTIVE: To evaluate the therapeutic effect that the titanium partial ossicular reconstruction prosthesis and autologous ossicles have on hearing loss after reconstruction of a damaged ossicular chain. METHODS: Forty-two medical records of treatments carried out from 2013 to 2015 for ossicular chain damage with facial nerve paralysis due to temporal bone fractures were reviewed. The study assessed: causes of damage, pre-operative pure tone audiometry findings, types of intra-operative ossicular chain damage, intra-operative ossicular chain repair methods (titanium partial ossicular reconstruction prosthesis or autologous ossicles) and post-operative pure tone audiometry results. RESULTS: The titanium partial ossicular reconstruction prosthesis was used in 26 cases; the average air-bone gap was 32.3 ± 5.3 dB pre-operatively and 12.8 ± 5.3 dB post-operatively. Autologous ossicles were used in 16 cases; the average air-bone gap was 33.4 ± 4.5 dB pre-operatively and 17.8 ± 7.8 dB post-operatively. CONCLUSION: Ossicular chain reconstruction is an effective way of improving hearing in patients with ossicular chain damage. The results suggest that repair with either the titanium partial ossicular reconstruction prosthesis or autologous ossicles can improve hearing following ossicular chain injury with facial nerve paralysis caused by a temporal bone fracture.

Total Ossicular Replacement Prosthesis: A New Fat Interposition Technique.

OBJECTIVE: To compare audiometric results between the standard total ossicular replacement prosthesis (TORP-S) and a new fat interposition total ossicular replacement prosthesis (TORP-F) in pediatric and adult patients and to assess the complication and the undesirable outcome. STUDY DESIGN: This is a retrospective study. METHODS: This study included 104 patients who had undergone titanium implants with TORP-F and 54 patients who had undergone the procedure with TORP-S between 2008 and 2013 in our tertiary care centers. The new technique consists of interposing a fat graft between the 4 legs of the universal titanium prosthesis (Medtronic Xomed Inc, Jacksonville, FL, USA) to provide a more stable TORP in the ovale window niche. Normally, this prosthesis is designed to fit on the stapes' head as a partial ossicular replacement prosthesis. RESULTS: The postoperative air-bone gap less than 25 dB for the combined cohort was 69.2% and 41.7% for the TORP-F and the TORP-S groups, respectively. The mean follow-up was 17 months postoperatively. By stratifying data, the pediatric cohort shows 56.5% in the TORP-F group (n = 52) compared with 40% in the TORP-S group (n = 29). However, the adult cohort shows 79.3% in the TORP-F group (n = 52) compared with 43.75% in the TORP-S group (n = 25). These improvements in hearing were statistically significant. There were no statistically significant differences in the speech discrimination scores. The only undesirable outcome that was statistically different between the 2 groups was the prosthesis displacement: 7% in the TORP-F group compared with 19% in the TORP-S group (P = .03). CONCLUSIONS: The interposition of a fat graft between the legs of the titanium implants (TORP-F) provides superior hearing results compared with a standard procedure (TORP-S) in pediatric and adult populations because of its better stability in the oval window niche.

Hearing results after type III tympanoplasty: incus transposition versus PORP. A systematic review.

OBJECTIVE: The objective of this study is to compare hearing improvements in the air-bone gap (ABG) after type III tympanoplasties, comparing between incus transposition (IT) and partial ossicular replacement prosthesis (PORP). MATERIALS AND METHODS: Publications in English were searched in PUBMED database and were systematically reviewed. A total of 14 articles were included, obtaining 1055 patients, 614 for the IT group and 441 for the PORP group. Preoperative ABG, postoperative ABG, dB gain and ABG closure rate were compared. RESULTS: IT group: preoperative ABG of 31.74 dB (SD 10.51); postoperative ABG of 18.97 dB (SD 10.6); dB gain of 12.76 dB (SD 14.97); and ABG closure rate of 64.48%. PORP group: preoperative ABG of 28.02 dB (SD 10.47); postoperative ABG of 16.27 dB (SD 10.45); dB gain of 11.75 (SD 15.02); and ABG closure rate of 71.32%. No significant statistical difference was found in dB mean gain between groups (p > .05), although a difference was found in the ABG closure rate between groups favouring PORP series (p < .05). CONCLUSION: An improvement in hearing results was observed within both groups after type III tympanoplasty. There is no difference in decibels gained between both ossiculoplasty materials, but a better closure rate (%) was observed in the PORP group.

Tympanoplasty - news and new perspectives.

Techniques and biomaterials for reconstructive middle ear surgery are continuously and steadily developing. At the same time, clinical post-surgery results are evaluated to determine success or failure of the therapy. Routine quality assessment and assurance is of growing importance in the medical field, and therefore also in middle ear surgery. The exact definition and acquisition of outcome parameters is essential for both a comprehensive and detailed quality assurance. These parameters are not the audiological results alone, but also additional individual parameters, which influence the postoperative outcome after tympanoplasty. Selection of patients and the preoperative clinical situation, the extent of the ossicular chain destruction, the chosen reconstruction technique and material, the audiometric frequency selection and the observational interval are only some of them. If these parameters are not well documented, the value of comparative analyses between different studies is very limited. The present overview aims at describing, comparing, and evaluating some of the existing assessment and scoring systems for middle ear surgery. Additionally, new methods for an intraoperative quality assessment in ossiculoplasty and the postoperative evaluation of suboptimal hearing results with imaging techniques are available. In the area of implant development, functional elements were integrated in prostheses to enable not only good sound transmission but also compensation of occurring atmospheric pressure changes. In combination with other components for ossicular repair, they can be used in a modular manner, which so far show experimentally and clinically promising results.

Data and Reporting Quality in Tympanoplasty and Ossiculoplasty Studies.

Objective The objective of our study was to check the documentation of hearing outcome parameters and influencing factors (surgical, pathological, and methodological) in published literature evaluating hearing outcome after tympanoplasty. We aimed to assess how effectively the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) 1995 guidelines were applied. Study Design Retrospective noncontrolled study. Setting Ear research center. Subjects and Methods This study was based on a PubMed research, including peer-reviewed English-speaking original studies published from January 2005 to December 2015. In total, 169 studies were checked for correct description of study population, surgical methodology, study design, and documentation of the hearing outcome. In addition, the correct application of AAO-HNS 1995 criteria was checked. Results Pre- and postoperative air-bone gap were shown as mean ± standard deviation in half of all series (52% vs 56%). The recommended frequency spectrum (0.5-3 kHz) was used in 46%, while a documentation of frequency spectrum was available in 85%. Whereas a statement on presence of stapes suprastructure (81%) and initial pathology was usually available, mucosa status (17%) and aeration (8%) were only shown in few series. Revision cases, staged cases, and myringoplasty graft material were documented in 46% to 57%. Type and material of prosthesis were represented in 74% to 82%. None of the publications analyzed fulfilled all 10 AAO-HNS criteria. In 10%, 7 to 9 criteria were used correctly. Conclusion A heterogeneous description of surgical and pathological findings and the application of minimal reporting standards are essential preconditions to enable comparisons between different studies and to generate meta-analysis.

Systematic Review of Ossicular Chain Anatomy: Strategic Planning for Development of Novel Middle Ear Prostheses.

Objective To systematically review the anatomy of the ossicular chain. Data Sources Google Scholar, PubMed, and otologic textbooks. Review Methods A systematic literature search was performed on January 26, 2015. Search terms used to discover articles consisted of combinations of 2 keywords. One keyword from both groups was used: [ ossicular, ossicle, malleus, incus, stapes] and [ morphology, morphometric, anatomy, variation, physiology], yielding more than 50,000 hits. Articles were then screened by title and abstract if they did not contain information relevant to human ossicular chain anatomy. In addition to this search, references of selected articles were studied as well as suggested relevant articles from publication databases. Standard otologic textbooks were screened using the search criteria. Results Thirty-three sources were selected for use in this review. From these studies, data on the composition, physiology, morphology, and morphometrics were acquired. In addition, any correlations or lack of correlations between features of the ossicular chain and other features of the ossicular chain or patient were noted, with bilateral symmetry between ossicles being the only important correlation reported. Conclusion There was significant variation in all dimensions of each ossicle between individuals, given that degree of variation, custom fitting, or custom manufacturing of prostheses for each patient could optimize prosthesis fit. From published data, an accurate 3-dimensional model of the malleus, incus, and stapes can be created, which can then be further modified for each patient's individual anatomy.

Cartilage island on stapes: autologous PORP in the hypoventilated middle ear.

The most common technique in sound restoration of the middle ear is prosthetic surgery. Hypoventilation of the middle ear may cause adhesive otitis or atelectasis resulting in a higher risk of prosthetic extrusion rate and recurrence of the underlying cholesteatoma. We report long-term results using an island of tragal cartilage as an autologous PORP in selected patients with poor middle ear ventilation. Retrospective chart reviews were performed for procedures involving 52 patients between year 2000 and 2009. All patients that underwent surgery using tragal cartilage interposed between the suprastructure of the stapes and the tympanic membrane were included in this study. Audiological parameters using four frequencies, 0.5, 1, 2 and 3 kHz, according to AAO-HNS guidelines, were assessed pre-and postoperatively. The hearing results on different PTA frequencies were also investigated. We report long-term follow-up of patients with hypoventilated middle ear with a success rate of 71% (ABG <20%). With regards to the ABG, the low frequency component (5 and 1 kHz) showed a significantly (p < 0.05) larger improvement of mean values after surgery as compared to the high-frequency component (2 and 3 kHz). Cartilage island PORP on stapes is a stable and efficient method for selected patients with chronic middle ear disease.

Effects of bacterial biofilm on hearing restoration with titanium partial ossicular prosthesis replacement / 医用生物力学

Objective To study effects of the bacterial biofilm at different growth stages on dynamic behavior of the titanium partial ossicular replacement prosthesis (PORP), so as to provide theoretical references for clinical treatment of diseases such as secretory otitis media. Methods Based on the CT scan images of normal human right ear and combined with the self compiling program, a 3D finite element model of the ear was reconstructed for dynamic analysis on sound conduction, and compared with the experimental data. The model was computed by harmonic response analysis method, and the sound conduction effect of bacterial biofilm grown on PORP at different growth stages was analyzed. Results The simulated amplitude of umbo and stapes footplate was in accordance with experimental measurements, which confirmed the validity of this numerical model. The existence of biofilm would cause 0-1.6 dB hearing loss at low frequencies. The growth of biofilm in the radial direction of PORP would cause 0-12 dB hearing loss at intermediate and high frequencies, especially at 8 kHz, and the hearing loss could be as high as 11.2 dB. Conclusions The bacterial biofilm has an impact on hearing by reducing the hearing at low frequencies while raising a little at high frequencies. The biofilm grown in the radial direction of PORP will reduce hearing, and affect the working efficiency of PORP on hearing restoration.