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Canal wall down mastoidectomy is performed when demanded by the extent of disease: presence of a large labyrinthine fistula, extensive erosion of posterior auditory canal wall, prior failed intact canal wall surgery, a contracted, sclerotic mastoid with extensive disease, or need for exteriorization due to inadequate exposure or inability to remove disease safely with a canal wall up approach.

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Surgery for cholesteatoma should be tailored to individual patients, considering demographic and disease factors, to obtain a dry, safe, and functional ear. The EAONO/JOS classification and staging system provide a valuable framework for data collection and outcome assessment. Canal wall-up and canal wall-down surgical approaches each have their advantages and disadvantages, though it is not definitive that one approach is clearly more advantageous than the other. Mastoid obliteration techniques show promise in reducing recidivistic disease rates but require further research and standardization. Endoscopic ear surgery further augments our surgical capabilities to visualize and eradicate cholesteatoma.

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Surgical treatment of cholesteatoma requires a highly individualized approach, balancing disease eradication with hearing preservation, and necessitates thorough patient counseling on expected auditory outcomes and options for rehabilitation. The choice between canal wall up and canal wall down mastoidectomy can influence hearing outcomes. Hearing rehabilitation options following cholesteatoma surgery include air- and bone-conduction devices and are individualized for the patient. Assistive listening devices such as frequency modulation systems, hearing loops, and Bluetooth technology are critical for enhancing speech understanding in noisy environments for patients who employ various hearing rehabilitation methods and require further advanced solutions.

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When surgically managing cholesteatoma, the Bondy modified radical mastoidectomy (MRM) and retrograde mastoidectomy can enhance visualization while minimizing the extent of surgery required for disease removal. The Bondy MRM can be used for disease limited to the atticoantral space, when the ossicles and middle ear space are otherwise healthy, and for canal cholesteatomas. The retrograde mastoidectomy offers a safe alternative for patients with unfavorable tegmen and sigmoid sinus positions and poorly pneumatized mastoids. Both approaches achieve favorable recidivism rates and postoperative hearing outcomes. This article serves as a reference regarding indications, techniques, and complications for these approaches.

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PURPOSE: Chronic otitis media with cholesteatoma is a frequent disease entity in otology, requiring surgery in overwhelming majority of cases. Despite the huge burden there is no established grading system available to assess the severity and extent of disease preoperatively until date. Aim of our study is to assess the applicability of ChOLE staging to preoperative HRCT temporal bone in Chronic otitis media with cholesteatoma. METHODOLOGY: Patients clinically diagnosed as COM with cholesteatoma, who underwent preoperative HRCT temporal bone imaging and mastoid exploration at our tertiary care centre were included. Preoperative radiology was assessed and a radiological ChOLE (r-ChOLE) was given by radiologist. This was then compared with the postop ChOLE. RESULTS: 21 patients were included in the study. Data was linear and normally distributed (Shapiro wilk test). Pearson's product-moment correlation used to see relationship between radiological and postop Total score showed strong statistically significant positive correlation with correlation coefficient (r) of 0.977. Paired t test showed p value was 0.329 (p > 0.05) suggesting no significant difference between radiological and postop Total scores. Cohen kappa test of agreement was applied. It revealed an overall strong agreement (p < 0.001). CONCLUSION: ChOLE staging may be extended to preoperative HRCT of temporal bone in COM with cholesteatoma (rCHOLE). A preoperative radiological staging will help in better prioritizing, planning and execution of tympanomastoid surgeries.

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BACKGROUND: Temporal bone computed tomography (CT) helps diagnose chronic otitis media (COM). However, its interpretation requires training and expertise. Artificial intelligence (AI) can help clinicians evaluate COM through CT scans, but existing models lack transparency and may not fully leverage multidimensional diagnostic information. OBJECTIVE: We aimed to develop an explainable AI system based on 3D convolutional neural networks (CNNs) for automatic CT-based evaluation of COM. METHODS: Temporal bone CT scans were retrospectively obtained from patients operated for COM between December 2015 and July 2021 at 2 independent institutes. A region of interest encompassing the middle ear was automatically segmented, and 3D CNNs were subsequently trained to identify pathological ears and cholesteatoma. An ablation study was performed to refine model architecture. Benchmark tests were conducted against a baseline 2D model and 7 clinical experts. Model performance was measured through cross-validation and external validation. Heat maps, generated using Gradient-Weighted Class Activation Mapping, were used to highlight critical decision-making regions. Finally, the AI system was assessed with a prospective cohort to aid clinicians in preoperative COM assessment. RESULTS: Internal and external data sets contained 1661 and 108 patients (3153 and 211 eligible ears), respectively. The 3D model exhibited decent performance with mean areas under the receiver operating characteristic curves of 0.96 (SD 0.01) and 0.93 (SD 0.01), and mean accuracies of 0.878 (SD 0.017) and 0.843 (SD 0.015), respectively, for detecting pathological ears on the 2 data sets. Similar outcomes were observed for cholesteatoma identification (mean area under the receiver operating characteristic curve 0.85, SD 0.03 and 0.83, SD 0.05; mean accuracies 0.783, SD 0.04 and 0.813, SD 0.033, respectively). The proposed 3D model achieved a commendable balance between performance and network size relative to alternative models. It significantly outperformed the 2D approach in detecting COM (P≤.05) and exhibited a substantial gain in identifying cholesteatoma (P<.001). The model also demonstrated superior diagnostic capabilities over resident fellows and the attending otologist (P<.05), rivaling all senior clinicians in both tasks. The generated heat maps properly highlighted the middle ear and mastoid regions, aligning with human knowledge in interpreting temporal bone CT. The resulting AI system achieved an accuracy of 81.8% in generating preoperative diagnoses for 121 patients and contributed to clinical decision-making in 90.1% cases. CONCLUSIONS: We present a 3D CNN model trained to detect pathological changes and identify cholesteatoma via temporal bone CT scans. In both tasks, this model significantly outperforms the baseline 2D approach, achieving levels comparable with or surpassing those of human experts. The model also exhibits decent generalizability and enhanced comprehensibility. This AI system facilitates automatic COM assessment and shows promising viability in real-world clinical settings. These findings underscore AI's potential as a valuable aid for clinicians in COM evaluation. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000036300; https://www.chictr.org.cn/showprojEN.html?proj=58685.

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PURPOSE: To investigate the impact of 3D-printed temporal bone models with two different material transparencies on trainees' mastoidectomy performance. METHODS: Eleven ORL residents performed two anatomical mastoidectomies with posterior tympanotomy on two 3D-printed models with different transparency and VR simulation training. Participants where divided into two groups based on their experience. Within each group participants were randomized to start with the model printed in a completely opaque material or in a material featuring some degree of transparency. After drilling on 3D-printed models, the participants performed two similar mastoidectomies on human cadavers: one on the left side of one cadaver and one on the right side of another cadaver. After drilling 3D-printed models and cadavers, the final-product performances were evaluated by two experienced raters using the 26-item modified Welling Scale. Participants also evaluated the models using a questionnaire. RESULTS: Overall, the participants performed 25 % better on the 3D-printed models featuring transparency compared to the opaque models (18.6 points vs 14.9 points, mean difference = 3.7, 95 % CI 2.0-5.3, P < 0.001)). This difference in performance was independent of which material the participants had drilled first. In addition, the residents also subjectively rated the transparent model to be closer to cadaver dissection. The experienced group starting with the 3D-printed models scored 21.5 points (95 % CI 20.0-23.1), while the group starting with VR simulation training score 18.4 points (95 % CI 16.6-20.3). CONCLUSION: We propose that material used for 3D-printing temporal bone models should feature some degree of transparency, like natural bone, for trainees to learn and exploit key visual cues during drilling.

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Pediatric cholesteatomas (PC) have multifactorial aetiology, spread aggressively and there are high chances of residual/ recurrent disease after treatment. The surgical technique to manage this entity has been debatable. This study was done to (i) enumerate the presentation of PC and the surgical techniques adopted (ii) analyse the outcomes viz., residual/ recurrence rates and hearing results. A cross sectional record based study was done on 618 cases of PC operated between 1983 and 2015, at a centre dedicated to otology and lateral skull base surgery. The data which was maintained on the basis of clinical and peri- operative findings was analysed. Otorrhea (59.2%) and hearing loss (54.2%) were the common symptoms. The surgeries done were: canal wall up (CWU) (44.3%), canal wall down (CWD) (41.1%), modified bondy's mastoidectomy (5.7%), radical mastoidectomy (4.9%), trans canal excision (1.8%) and subtotal petrosectomy (2.3%). The residual and recurrence rates were 12.6% and 7.9% respectively. A significant difference between the pre and post operative hearing was observed. The mean improvement in air bone gap was 7.7db. Residual/ recurrent disease were higher in CWU as compared to CWD group. The surgery should be individualised so that the patient remains disease free.

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Objective:To analyze the surgical efficacy and safety of tympanoplasty with and without mastoidectomy for the treatment of active simple chronic suppurative otitis media（CSOM）, and to investigate whether mastoidectomy can be avoided in tympanoplasty for active CSOM. Methods:The clinical data of 55 patients（55 ears） with active CSOM were retrospectively analyzed. Based on the development of the mastoid process and the upper tympanic chamber, patients who met the criteria for wall-up mastoidectomy were classified as group A （30 patients）, and underwent tympanoplasty combined with wall-up mastoidectomy. Patients who did not meet the criteria for wall-up mastoidectomy were classified as group B（25 cases）, and underwent tympanoplasty with the opening of the middle and upper tympanic chambers and sinus drainage after partial removal of the shield plate bone. The survival rate of tympanic membrane grafts, hearing before and after surgery, and complications such as reperforation were compared between the two groups at 3 months postoperatively. Results:The overall postoperative tympanic membrane survival rate of patients with active CSOM was 96.4%（53/55）, including 96.7% in group A; 96.0% in group B. There was no significant difference in the tympanic membrane survival rate between the two groups（P>0.05）. The postoperative mean air-bone gap（ABG） was significantly reduced in both groups compared with the preoperative period, but there was no significant difference in ABG gain between the two groups（P>0.05）. No patients experienced serious adverse conditions such as peripheral facial paralysis, cerebrospinal fluid leakage, or sensorineural deafness after surgery. Conclusion:Microscopic tympanoplasty with patency of the middle and upper tympanic chambers and tympanic sinus drainage can be used to treat active simple chronic otitis media with satisfactory tympanic membrane viability and hearing improvement efficacy. This approach reduces patient trauma, prevents complications such as skin depressions in the mastoid area due to abrasion of the mastoid bone, and shortens the waiting time before surgery.

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BACKGROUND AND OBJECTIVES: Various materials are used to perform post-mastoidectomy mastoid obliteration (MO) to reduce the risk of recurrent infections, stasis of secretions, or caloric dizziness. Autologous materials used as fillers for MO tend to be insufficient owing to shrinkage over time or inadequate volume of these substances. Synthetic materials are unsatisfactory for MO because of the risk of rejection and extrusion. We investigated the safety and effectiveness of bone allografts for post-mastoidectomy MO. SUBJECTS AND METHODS: We reviewed the medical records of patients who underwent mastoidectomy with MO between January 2013 and January 2021. In the MO group, bone allografts were additionally used to fill the residual mastoid cavity. In the canal wall down (CWD) group, all patients underwent CWD mastoidectomy with use of additional inferiorly based mucoperiosteal flaps. RESULTS: The study included the MO group (23 ears) and the CWD group (53 ears). In the MO group, compared with the preoperative status, we observed a decrease in the tendency of the air-bone gap postoperatively. Compared with the CWD group, the total complication rate showed a decreasing tendency in the MO group. CONCLUSIONS: No patient showed post-MO shrinkage of the grafted bone allograft or otorrhea. Further large-scale studies are warranted to confirm the advantages of bone allografts for MO, including maintenance with time and sufficient amount.

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INTRODUCTION: Acute pediatric mastoiditis is a bacterial infection of the mastoid bone most commonly associated with acute otitis media. Complicated mastoiditis is traditionally characterized by intracranial complications or subperiosteal abscess, but definitions are inconsistent in the literature. Surgical intervention is identified as the main treatment for complicated mastoiditis, but there is some evidence to support medical management of uncomplicated mastoiditis. This study sought to clarify the diagnostic criteria and management of uncomplicated acute mastoiditis. METHODS: All cases of acute pediatric mastoiditis were identified from a single institution over a 16-year period and reviewed for demographic and clinical data. Two different definitions of uncomplicated mastoiditis were compared; the traditional one that excluded patients with intracranial complications or subperiosteal abscess (SPA) and the proposed definition that also excluded patients with any evidence of bony erosion including coalescence, not just SPA. Univariate and multivariate analysis was conducted. RESULTS: Eighty cases were identified. Using the traditional definition of uncomplicated mastoiditis, 46.3% of cases were uncomplicated, compared to 36.2% when using the proposed definition. Truly uncomplicated patients, categorized with the proposed definition, were treated more consistently: no patients underwent mastoidectomy and they were less likely to receive a long term course of antibiotics. On multivariate regression analysis, only categorization with the proposed definition of uncomplicated mastoiditis was independently associated with less long-term antibiotic therapy and non-surgical management. CONCLUSION: Uncomplicated acute mastoiditis should be defined using clinical criteria and exclude any cases with evidence of bony erosion, including coalescence or subperiosteal abscess. These truly uncomplicated patients often do not require mastoidectomy and can be prescribed a shorter course of antibiotics. Further research into treatment pathways is necessary to optimize the management of uncomplicated acute pediatric mastoiditis.

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Background: The development of temporal bone pneumatization is related to the postnatal middle ear environment, where the development of air cells is suppressed with otitis media in early childhood. However, whether air cell formation restarts when mastoidectomy is performed during temporal bone pneumatization remains unclear. Herein, we evaluated temporal bone pneumatization after canal wall up (CWU) tympanomastoidectomy for middle ear cholesteatoma in children. Methods: In total, 63 patients, including 29 patients with congenital cholesteatoma (CC) and 34 patients with acquired cholesteatoma (AC), were assessed using a set of pre- and postoperative computed tomography images. The air cells of the temporal bone were divided into five areas: periantral (anterior), periantral (posterior), periantral (medial), peritubal, and petrous apex. The number of areas with air cells before and after surgery was compared to evaluate temporal bone pneumatization after surgery. Results: A total of 63 patients, comprising 29 with CC and 34 with AC (pars flaccida; 23, pars tensa; 7, unclassified; 4), were evaluated. The median age of patients (18 males and 11 females) with CC was 5.0 (range, 2-15 years), while that of the AC group (23 males and 11 females) was 8 (range, 2-15 years). A significant difference in air cell presence was identified in the CC and AC groups after surgery (Mann-Whitney U, p < 0.001 and p = 0.003, respectively). Between the two groups, considerably better postoperative pneumatization was observed in the CC group. A correlation between age at surgery and gain of postoperative air cell area development was identified in the CC group (Spearman's rank-order correlation coefficient, r = -0.584, p < 0.001). In comparison with the postoperative pneumatization rate of each classified area, the petrous apex area was the lowest in the CC and AC groups. Conclusions: Newly developed air cells were identified in the temporal bones after CWU mastoidectomy for pediatric cholesteatoma. These findings may justify CWU tympanomastoidectomy, at least for younger children and CC patients, who may subsequently develop air cell systems after surgery.

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The facial nerve supplies motor, sensory, and parasympathetic innervation to the head and neck, and its paralysis can have significant physical and psychological impacts. This study discusses a compelling case involving a 21-year-old male who developed delayed facial nerve palsy (DFNP) on the eighth day after cortical mastoid surgery. Through conservative management, the patient achieved a full recovery by the 52nd day. Our experience underscores the importance of approaching DFNP with patience, emphasizing the need for thorough counseling of both the patient and their family members.

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PURPOSE: After the lifting of nonpharmaceutical interventions (NPIs) during the COVID-19 pandemic, clinical observation showed an increase in complications of acute otitis, followed by a rise in the number of mastoidectomies performed. The aim of this study was to record the number of mastoidectomies performed before, during and after the COVID-19 pandemic as an indicator for complications of acute otitis media. METHODS: Data were collected from a tertiary hospital in a university setting, as well as from four major public health insurance companies in Germany. The data of 24,824,763 German citizens during a period from 2014 until 2023 were analyzed. RESULTS: According to the data, during the COVID-19 pandemic, the number of mastoidectomies performed dropped by 54% for children aged 0-6 and by 62% for children aged 7-18. For adults, there were 30% fewer mastoidectomies performed between 2020 and 2022. After the lifting of most NPI's in the season from July 2022 to June 2023, there was a sharp increase in the number of mastoidectomies performed on patients of all ages. CONCLUSIONS: During the COVID-19 pandemic, a decrease in the number of mastoidectomies performed was seen, suggesting a lower incidence of complicated acute otitis, most likely linked to the general decrease of upper airway infections due to NPI's. In contrast, a sharp increase in the incidence of complicated otitis occurred after the hygiene measures were lifted. The current development causes a more frequent performance of mastoidectomies, thus entailing a change in the challenges for everyday clinical practice.

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OBJECTIVE: To compare the cost-effectiveness of serial non-echo planar diffusion weighted MRI (non-EP DW MRI) versus planned second look surgery following initial canal wall up tympanomastoidectomy for the treatment of cholesteatoma. METHODS: A decision-analytic model was developed. Model inputs including residual cholesteatoma rates, rates of non-EP DW MRI positivity after surgery, and health utility scores were abstracted from published literature. Cost data were derived from the 2022 Centers for Medicare and Medicaid Services fee rates. Efficacy was defined as increase in quality-adjusted life year (QALY). One- and 2-way sensitivity analyses were performed on variables of interest to probe the model. Total time horizon was 50 years with a willingness to pay (WTP) threshold set at $50 000/QALY. RESULTS: Base case analysis revealed that planned second-look surgery ($11 537, 17.30 QALY) and imaging surveillance with non-EP DWMRI ($10 439, 17.26 QALY) were both cost effective options. Incremental cost effectiveness ratio was $27 298/QALY, which is below the WTP threhshold. One-way sensitivity analyses showed that non-EP DW MRI was more cost effective than planned second-look surgery if the rate of residual disease after surgery increased to 48.3% or if the rate of positive MRI was below 45.9%. A probabilistic sensitivity analysis at WTP of $50 000/QALY found that second-look surgery was more cost-effective in 56.7% of iterations. CONCLUSION: Non-EP DW MRI surveillance is a cost-effect alternative to planned second-look surgery following primary canal wall up tympanomastoidectomy for cholesteatoma. Cholesteatoma surveillance decisions after initial canal wall up tympanomastoidectomy should be individualized. LEVEL OF EVIDENCE: V.

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Chronic Otitis Media (COM) with complications is a common clinical entity in Otorhinolaryngology, but advances in antibiotics and surgical techniques have reduced complication rates and mortality. Management warrants surgical disease clearance, the choice of surgical approach of which may vary. Endaural approach is a less commonly performed approach in view of its complexity and surgical expertise. This case report presents a 13-year-old female with COM-squamous active type with cerebellar abscess, managed with Lempert's endaural mastoidectomy. The patient presented with long-standing left sided purulent ear discharge, ear pain, headache, and vomiting. Diagnosis included bilateral COM-squamous active type with left cerebellar abscess, status post suboccipital craniotomy. Endaural mastoidectomy was performed to circumvent the pseudomeningocoele and achieve disease clearance. Postoperative follow-up showed well-healed scars and no evidence of disease recurrence. Chronic Otitis Media with complications requires surgical management to prevent disease progression and related complications. Surgical approaches for disease clearance include post aural and endaural techniques. Lempert's endaural approach provided a superior view of the middle ear and mastoid, facilitating disease clearance and simplifying postoperative care with enhanced cosmesis. Although endaural approach demands surgical expertise, it can be a viable option for complicated cases. In this case, Lempert's endaural canal wall down mastoidectomy effectively managed COM-squamous active type with cerebellar abscess, offering a clear view of the disease epicenter with limited bone removal. The endaural approach, in the hands of an experienced surgeon, can be a feasible alternative for surgical clearance in complicated COM cases, providing favorable outcomes with superior visibility and cosmesis.

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Objective: To describe our modifications to the submental island flap (SMIF) in a case series that demonstrates improved reproducibility, shortened length of stay (LOS), and reduced utilization of hospital resources. Study Design: This retrospective case series with chart review included adult patients who underwent resection of malignant or benign tumors resulting in lateral facial, parotid, or temporal bone defects, which were reconstructed with SMIF. Setting: A tertiary-care academic referral center. Methods: Retrospective case series included all adult patients who underwent SMIF reconstruction between March 2020 and August 2021. Patient demographic and clinical data were collected. Primary outcomes were measures of hospital utilization including duration of surgery, LOS, and postoperative outcomes. Results: Twenty-eight patients were included with a mean age of 71.7 years. Eighty percent were male. All patients underwent parotidectomy, and the mean operative time was 347 minutes. The median LOS was 2.5 days (range 0-16 days). Seventy-five percent of the flaps drained into the internal jugular vein, and 25% drained into the external jugular vein. No patients required reoperation or readmission. All flaps survived. Conclusion: SMIFs are a safe and effective option for reconstruction of lateral facial, parotid, and temporal bone defects. Compared to free flap reconstruction, SMIFs offer reduced length of surgery, decreased use of health care resources, and lower rate of reoperation. As health care resource allocation is increasingly important, the SMIF offers an excellent alternative to free flap reconstruction of lateral defects.

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OBJECTIVE: This study aimed to assess the effect of drilling during mastoidectomy on otolithic organ functions and development of benign paroxysmal positional vertigo using objective vestibular tests. MATERIALS AND METHODS: The study included 45 adult patients diagnosed with chronic otitis media who underwent mastoidectomy with drilling. Pre-operative and post-operative assessments included tests for subjective visual vertical deviation and videonystagmography. RESULTS: Subjective visual vertical deviation was significantly higher in post-operative periods. On the third day, the subjective visual vertical deviation was at its maximum (1.4 degrees). Post-operatively, benign paroxysmal positional vertigo was detected in 14 patients (31.1 per cent). The most common type was ipsilateral lateral canal benign paroxysmal positional vertigo (57.1 per cent). CONCLUSION: The effect of drilling on otolithic organ functions in mastoidectomy seems to be temporary and subclinical; however, it potentially could be a risk factor for the development of benign paroxysmal positional vertigo.

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Complex temporal bone anatomy complicates operations; thus, surgeons must engage in practice to mitigate risks, improving patient safety and outcomes. However, existing training methods often involve prohibitive costs and ethical problems. Therefore, we developed an educational mastoidectomy simulator, considering mechanical properties using 3D printing. The mastoidectomy simulator was modeled on computed tomography images of a patient undergoing a mastoidectomy. Infill was modeled for each anatomical part to provide a realistic drilling sensation. Bone and other anatomies appear in assorted colors to enhance the simulator's educational utility. The mechanical properties of the simulator were evaluated by measuring the screw insertion torque for infill specimens and cadaveric temporal bones and investigating its usability with a five-point Likert-scale questionnaire completed by five otolaryngologists. The maximum insertion torque values of the sigmoid sinus, tegmen, and semicircular canal were 1.08 ± 0.62, 0.44 ± 0.42, and 1.54 ± 0.43 N mm, displaying similar-strength infill specimens of 40%, 30%, and 50%. Otolaryngologists evaluated the quality and usability at 4.25 ± 0.81 and 4.53 ± 0.62. The mastoidectomy simulator could provide realistic bone drilling feedback for educational mastoidectomy training while reinforcing skills and comprehension of anatomical structures.

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BACKGROUND: Given that the temporal bone is one of the most complex regions of the human body, cadaveric dissection of this anatomical area represents the first necessary step for the learning and training of the young oto-surgeon in order to perform middle ear surgery, which includes the management of inflammatory pathology, hearing rehabilitation, and also cognitive decline prevention surgery. The primary objective of this study was to identify common mistakes and critical passages during the initial steps of temporal bone dissection, specifically cortical mastoidectomy and posterior tympanotomy. METHODS: A survey among 100 ENT residents was conducted, gathering insights into the most prevalent errors encountered during their training to uncover the most challenging aspects faced by novice surgeons during these procedures. RESULTS: The most common mistakes included opening the dura of the middle cranial fossa (MCF), injury of the sigmoid sinus (SS), chorda tympani (CT), and facial nerve (FN) injury while performing the posterior tympanotomy. The most important critical steps to prevent mistakes are related to the absence of wide exposure during cortical mastoidectomy and the consequent impossibility of identifying the landmarks of the facial recess before performing posterior tympanotomy. Injury of these structures was more common in younger surgeons and in the ones who performed less than five temporal bone dissection courses. CONCLUSIONS: Numerous temporal bone dissections on cadavers are mandatory for ENT residents looking forward to performing middle ear surgery.