Bone cement repair of malleus handle fractures: Intraoperative video and case report of two patients.

Isolated malleus fractures are a rare occurrence with few reported cases in the literature. Symptoms include sudden otalgia, hearing loss, tinnitus and aural fullness. Work-up and diagnosis are based on a combination of thorough anamnesis and careful otoscopic evaluation or high-resolution computer tomography. We present two cases of isolated malleus handle fractures who were diagnosed based on a combination of pneumatic otoscopy and tympanometry. Both fractures were surgically repaired using hydroxyapatite bone cement as showcased in the supplemental video material. Post-operative audiometry showed improvement in the pure-tone-average of both patients as well as normalisation of tympanometry. Isolated malleus fracture should be suspected in cases of sudden hearing loss and tinnitus following digital manipulation of the outer ear canal together with a conductive hearing loss with a mostly high-frequent air-bone-gap and hypercompliant tympanometry with hypermobility of the tympanic membrane on pneumatic insufflation. Surgical repair of the fracture using bone cement has good hearing outcomes and leads to improvement in auditory symptoms.

Registration of preoperative temporal bone CT-scan to otoendoscopic video for augmented-reality based on convolutional neural networks.

PURPOSE: Patient-to-image registration is a preliminary step required in surgical navigation based on preoperative images. Human intervention and fiducial markers hamper this task as they are time-consuming and introduce potential errors. We aimed to develop a fully automatic 2D registration system for augmented reality in ear surgery. METHODS: CT-scans and corresponding oto-endoscopic videos were collected from 41 patients (58 ears) undergoing ear examination (vestibular schwannoma before surgery, profound hearing loss requiring cochlear implant, suspicion of perilymphatic fistula, contralateral ears in cases of unilateral chronic otitis media). Two to four images were selected from each case. For the training phase, data from patients (75% of the dataset) and 11 cadaveric specimens were used. Tympanic membranes and malleus handles were contoured on both video images and CT-scans by expert surgeons. The algorithm used a U-Net network for detecting the contours of the tympanic membrane and the malleus on both preoperative CT-scans and endoscopic video frames. Then, contours were processed and registered through an iterative closest point algorithm. Validation was performed on 4 cases and testing on 6 cases. Registration error was measured by overlaying both images and measuring the average and Hausdorff distances. RESULTS: The proposed registration method yielded a precision compatible with ear surgery with a 2D mean overlay error of 0.65 ± 0.60 mm for the incus and 0.48 ± 0.32 mm for the round window. The average Hausdorff distance for these 2 targets was 0.98 ± 0.60 mm and 0.78 ± 0.34 mm respectively. An outlier case with higher errors (2.3 mm and 1.5 mm average Hausdorff distance for incus and round window respectively) was observed in relation to a high discrepancy between the projection angle of the reconstructed CT-scan and the video image. The maximum duration for the overall process was 18 s. CONCLUSIONS: A fully automatic 2D registration method based on a convolutional neural network and applied to ear surgery was developed. The method did not rely on any external fiducial markers nor human intervention for landmark recognition. The method was fast and its precision was compatible with ear surgery.

Comparative validity of three simulation platforms for objective assessment of otoscopy skills.

OBJECTIVES: To assess the face, construct and content validity of three different platforms for otoscopy skills assessment, using a traditional otoscope with manikin, digital otoscope (Tympahealth) with manikin, and traditional otoscope with a low-cost model ear (SimEar). DESIGN: Prospective mixed methods study. SETTING: Tertiary hospital. PARTICIPANTS: Postgraduate trainees and expert assessors. MAIN OUTCOME MEASURES: Face and Content validity based on expert assessor ranking on each model and their feedback from semi-structured interviews. Construct validity based on Objective Structured Clinical Examination scores. RESULTS: Each platform differed in face, construct and content validity scores, with no one platform consistently outperforming others. Three main themes were identified during thematic analysis of expert assessor interviews: ability to assess what is seen, anatomical reality, and ease of use. The low-cost model showed greatest potential, where modification to include a silicone ear could lead to high validity with marginal increase in cost. CONCLUSION: Several modalities for assessing otoscopy skills exist, each with advantages and disadvantages. Modifications to a low-cost model, for use with either a traditional or digital otoscope, could prove to be the best model.

Endoscopic ear examination improves self-reported confidence in ear examination skills among undergraduate medical students compared with handheld otoscopy.

Objectives: Handheld otoscopy is the standard tool used to teach ear examination in undergraduate and postgraduate medical education. Previous studies have shown that the undergraduate teaching of ear examination with handheld otoscopes is inadequate, resulting in low self-reported levels of student confidence in their diagnostic skills. With the increase in popularity of endoscopic ear surgery, an increasing number of otolaryngologists are using endoscopes for office examinations of the ear due to the method's superior visualization and excellent image qualities. However, medical students usually do not receive exposure to endoscopic ear examination during their undergraduate curriculum. The aim of this study is to assess our preliminary experience with teaching endoscopic ear examination to undergraduate medical students. Methods: A two-hour-long pilot practical course on basic ear examination was administered to undergraduate medical students with little to no previous experience with ear examination. The course was designed to minimize the duration of campus attendance and patient contact during the COVID-19 pandemic. The course included theoretical didactics, exemplary digital endoscopic images and peer physical practice of ear examination with both a handheld otoscope and a 0-degree endoscope. At the end of the course, the students completed a survey questionnaire consisting of eight questions mainly relating to their subjective confidence level with ear examination using either handheld otoscopes or endoscopes and their overall preference for either examination tool. Results: Most students expressed a preference for ear examination with endoscopes over that with handheld otoscopes and reported an improved confidence level in their diagnostic ability with the former technique. The vast majority of students supported the teaching of endoscopic ear examination to future medical students. Conclusion: The findings of this pilot project report and survey study support the early exposure of novice medical learners to endoscopic ear examination, which may help improve the confidence and diagnostic skill of medical students with regard to ear examination. The findings may have implications for the undergraduate teaching of ear examination in the post-COVID-19 era.

Artificial intelligence to classify ear disease from otoscopy: A systematic review and meta-analysis.

OBJECTIVES: To summarise the accuracy of artificial intelligence (AI) computer vision algorithms to classify ear disease from otoscopy. DESIGN: Systematic review and meta-analysis. METHODS: Using the PRISMA guidelines, nine online databases were searched for articles that used AI computer vision algorithms developed from various methods (convolutional neural networks, artificial neural networks, support vector machines, decision trees and k-nearest neighbours) to classify otoscopic images. Diagnostic classes of interest: normal tympanic membrane, acute otitis media (AOM), otitis media with effusion (OME), chronic otitis media (COM) with or without perforation, cholesteatoma and canal obstruction. MAIN OUTCOME MEASURES: Accuracy to correctly classify otoscopic images compared to otolaryngologists (ground truth). The Quality Assessment of Diagnostic Accuracy Studies Version 2 tool was used to assess the quality of methodology and risk of bias. RESULTS: Thirty-nine articles were included. Algorithms achieved 90.7% (95%CI: 90.1-91.3%) accuracy to difference between normal or abnormal otoscopy images in 14 studies. The most common multiclassification algorithm (3 or more diagnostic classes) achieved 97.6% (95%CI: 97.3-97.9%) accuracy to differentiate between normal, AOM and OME in three studies. AI algorithms outperformed human assessors to classify otoscopy images achieving 93.4% (95%CI: 90.5-96.4%) versus 73.2% (95%CI: 67.9-78.5%) accuracy in three studies. Convolutional neural networks achieved the highest accuracy compared to other classification methods. CONCLUSION: AI can classify ear disease from otoscopy. A concerted effort is required to establish a comprehensive and reliable otoscopy database for algorithm training. An AI-supported otoscopy system may assist health care workers, trainees and primary care practitioners with less otology experience identify ear disease.

Bilateral cholesterol granulomas in the middle ear cavities of a cat with sinonasal disease successfully removed via video-otoscopy.

CASE DESCRIPTION: A 9-year-old spayed female Maine Coon cat was presented at the University of Veterinary Medicine Vienna for further investigation of chronic nonpruritic bilateral ear disease and unilateral Horner syndrome. CLINICAL FINDINGS: Physical examination and otoscopy findings included right sided Horner syndrome, a right head tilt of approximately 20° and a small pink nodule in the right and several smaller nodules in the left proximal horizontal external ear canal. Computed tomography and magnetic resonance imaging revealed soft tissue opacity material in both middle ear cavities, the caudal portion of the nasal cavity, the left nasopharyngeal meatus and the right frontal sinus. Via videootoscopy, 2 multilobular and several flat nodules were detected in the proximal right horizontal external ear canal and in the left tympanic bulla, respectively. Histopathological examination confirmed the diagnosis of cholesterol granulomas. TREATMENT AND OUTCOME: All otic cholesterol granulomas (CGs) were removed via video-otoscopy (VO), and topical treatment was initiated in addition to oral prednisolone. After the histopathological confirmation, negative microbial cultures from the middle ear cavities, and the remission of the symptoms by the first recheck, topical, and systemic treatment were discontinued. A follow-up 6 months later, did not reveal any recurrence of the CGs. CLINICAL RELEVANCE: To our knowledge, this is the first case of bilateral CGs diagnosed with a combination of CT, MRI, VO, and histopathology and removed minimal invasively via VO, without a need for ventral bulla osteotomy, which led to complete remission of all signs and no relapse until the follow up 6 months later.

Otoendoscopes to Enhance Telemedicine During the COVID-19 Pandemic.

OBJECTIVES: As telemedicine has become increasingly utilized during the COVID-19 pandemic, portable otoendoscopy offers a method to perform an ear examination at home. The objective of this pilot study was to assess the quality of otoendoscopic images obtained by non-medical individuals and to determine the effect of a simple training protocol on image quality. METHODS: Non-medical participants were recruited and asked to capture images of the tympanic membrane before and after completion of a training module, as well as complete a survey about their experience using the otoendoscope. Images were de-identified, randomized, and evaluated by 6 otolaryngologists who were blinded as to whether training had been performed prior to the image capture. Images were rated using a 5-point Likert scale. RESULTS: Completion of a training module resulted in a significantly higher percentage of tympanic membrane visible on otoendoscopic images, as well as increased physician confidence in identifying middle ear effusion/infection, cholesteatoma, and deferring an in-person otoscopy (P < .0001). However, even with improved image quality, in most cases, physicians reported that they would not feel comfortable using the images to for diagnosis or to defer an in-person examination. Most participants reported that the otoendoscope was simple to use and that they would feel comfortable paying for the device. CONCLUSIONS: At-home otoendoscopes can offer a sufficient view of the tympanic membrane in select cases. The use of a simple training tool can significantly improve image quality, though often not enough to replace an in-person otoscopic exam.

Face, Content, and Construct Validity of a Virtual Reality Otoscopy Simulator and Applicability to Medical Training.

OBJECTIVE: Otologic diseases are common in all age groups and can significantly impair the function of this important sensory organ. To make a correct diagnosis, the correct handling of the otoscope and a correctly performed examination are essential. A virtual reality simulator could make it easier to teach this difficult-to-teach skill. The aim of this study was to assess the face, content, and construct validity of the novel virtual reality otoscopy simulator and the applicability to otologic training. STUDY DESIGN: Face and content validity was assessed with a questionnaire. Construct validity was assessed in a prospectively designed controlled trial. SETTING: Training for medical students at a tertiary referral center. METHOD: The questionnaire used a 6-point Likert scale. The otoscopy was rated with a modified Objective Structured Assessment of Technical Skills. Time to complete the task and the percentage of the assessed eardrum surface were recorded. RESULTS: The realism of the simulator and the applicability to medical training were assessed across several items. The ratings suggested good face and content validity as well as usefulness and functionality of the simulator. The otolaryngologists significantly outperformed the student group in all categories measured (P < .0001), suggesting construct validity of the simulator. CONCLUSION: In this study, we could demonstrate face, content, and construct validity for a novel high-fidelity virtual reality otoscopy simulator. The results encourage the use of the otoscopy simulator as a complementary tool to traditional teaching methods in a curriculum for medical students.

Comprehensive Community Screening of Otological Patients by Trained Technicians Using a Telemedicine Device: An Efficient and Cost-Effective Way to Triage Patients With Ear Diseases.

OBJECTIVE: To emphasize the benefits of tele-otology in community screening of patients with ear diseases. METHODS: A retrospective study of all patients screened and treated under the Shruti tele-otology program between 2013 and 2019 was conducted. It involved screening, diagnosis, medical management, surgical intervention, and rehabilitation using hearing aid. The study focused on underprivileged and underserved community of rural and urban slums across 12 states of India. The study was conducted using a telemedicine device called ENTraview, that is, a camera-enabled android phone integrated with an otoscope and audiometry screening. RESULT: A total of 810 746 people were screened, and incidence of various ear diseases was recorded. Ear problems were found in 265 615 (33%) patients, of which 151 067 (57%) had impacted wax, 46 792(18%) had chronic suppurative otitis media, 27 875 (10%) had diminished hearing, 12 729 (5%) had acute otitis media and acute suppurative otitis media (ASOM), and 27 152 (10%) had problems of foreign body, otomycosis, and so on. Of the total 265 615 referred patients, 20 986 (8%) reported for treatment and received treatment at a significantly reduced cost through Shruti program partners. The conversion rate of nonsurgical and surgical procedure was also compared, and it was found that, while 9% of the patients opted for nonsurgical treatment, only 3% opted for surgery in the intervention group giving a significant P value of .00001. CONCLUSION: The potential for telemedicine to reduce inequalities in health care is immense but remains underutilized. Shruti has largely been able to bridge this gap as it is an innovative, fast, and effective programs that address the ear ailment in the community.

Acellular Collagen Scaffold With Basic Fibroblast Growth Factor for Repair of Traumatic Tympanic Membrane Perforation in a Rat Model.

OBJECTIVE: To evaluate the efficacy of acellular collagen scaffold (ACS) in combination with basic fibroblast growth factor (bFGF) for the repair of traumatic tympanic membrane (TM) perforation in a rat model. STUDY DESIGN: A prospective controlled animal study in a rat model of traumatic TM perforation. SETTING: Tertiary medical center. SUBJECTS AND METHODS: Sprague-Dawley rats (N = 84) with unilateral traumatic perforation of the right TMs were randomized to receive ACS, bFGF, ACS in combination with bFGF (ACS/bFGF), or nothing (spontaneous healing without any interventions as a control group). The healing outcomes were evaluated by otoscopy, optical coherence tomography, histology, and transmission electron microscopy at 1, 2, and 4 weeks postoperatively. The hearing outcomes were assessed with auditory brainstem response testing. RESULTS: ACS/bFGF resulted in higher perforation closure rates at an earlier stage than spontaneous healing, ACS, and bFGF. Based on histology, optical coherence tomography, and transmission electron microscopy, a trilaminar structure and uniform thickness with mature, densely packed collagen fibers were seen in the ACS/bFGF group. Auditory brainstem response evaluation also showed that ACS/bFGF treatment promoted faster functional hearing recovery as compared with the control group. CONCLUSIONS: ACS is an effective TM scaffold and a carrier for bFGF. ACS/bFGF improves the TM closure rate, results in better-reconstructed TMs, and improves hearing. ACS/bFGF serves as a potential substitute for TM perforations in clinical settings.

Comparison of clinical outcome between endoscopic and postauricular incision microscopic type-1 tympanoplasty.

BACKGROUND: Microscopic type-1 tympanoplasty (T1T) is a classical method for the treatment of chronic otitis media. However, it has its limitations. The development of otoendoscopy provided a new method for T1T. OBJECTIVE: To investigate the difference between endoscopic T1T and microscopic T1T. MATERIAL AND METHODS: Seventy-four patients who underwent T1T were evaluated retrospectively. About 52 cases underwent endoscopic T1T, and 22 cases accepted microscopic T1T. Parameters including operative duration, incision size, graft site, duration of postoperative hospitalization, visual analog scale (VAS) score, complications, hearing improvement, and expenses were compared. RESULTS: Operative duration of endoscopic T1T (47.0 ± 8.2 min) was shorter than microscopic T1T (58.0 ± 9.3 min) (p < .05). The VAS score under endoscopic T1T (1.5 ± 0.2) was lower than microscopic T1T (5.6 ± 0.4) (p < .05). There was no complication during endoscopic T1T, but damage to the chorda tympani nerve (one case) was noted for microscopic T1T. There was no difference in hearing improvement between endoscopic (15.0 ± 1.5 dB) and microscopic T1T (16.0 ± 1.1 dB). Duration of postoperative hospitalization and expenses were lower for endoscopic T1T. CONCLUSIONS AND SIGNIFICANCE: Endoscopic T1T is a minimally invasive surgery with similar graft success rate, comparable hearing improvement, fast recovery, low cost, and high patient satisfaction compared to microscopic T1T.

Ventilation tube non-function due to blockage in children: the frequency, course and effect on hearing. A prospective cohort study.

OBJECTIVE: To assess the effect on hearing of non-functioning ventilation tubes due to blockage during the first six months post-operatively, using UK national guidelines. METHOD: A prospective, observational study was conducted on 37 children who underwent bilateral ventilation tube insertion. Air and bone conduction thresholds were measured before and following surgery, and at one, three and six months post-operatively. Tube non-function was assessed by tympanometry supported by otoscopy. RESULTS: Post-operatively, an average of 21 per cent of ventilation tubes were non-functioning. Ears with non-functioning tubes had significantly (p = 0.0001) poorer mean air conduction thresholds than functioning tubes, with a magnitude of 6 dB HL. Ears with otorrhoea were most affected (15 per cent). At any one visit, the air-bone gap was closed to 10 dB or less in 76 per cent of ears. Non-functioning tubes reduced this to 56 per cent. Compared with tympanometry, otoscopy underdiagnosed tube non-function due to blockage by 22 per cent. CONCLUSION: Non-functioning of ventilation tubes occurs frequently and can be missed on otoscopy. Although it is associated with poorer air conduction thresholds, the magnitude of this difference is unlikely to warrant further intervention unless there is otorrhoea or recurrence of bilateral hearing impairment.

Pediatric, Family-Centered, "At-Home" Otologic Physical Examination in the COVID-19 Era.

SARS-CoV-2, the novel coronavirus resulting in the present COVID-19 pandemic, has increased the otolaryngologist's reliance on telemedicine to manage outpatient pathology. The nature of telemedicine, however, limits a provider's ability to obtain a comprehensive physical examination, specifically of the tympanic membrane. Various smartphone-based otoscopic attachments are now available that facilitate patient-obtained otoscopic image capture of the tympanic membrane. Here, we present 3 cases in which a patient-purchased, over-the-counter otoscope was utilized to alter otologic management during the time of social distancing. Further research is necessary to improve our understanding the safety and efficacy of patient-based "at-home" otoscopic examination and to optimize the use of these devices.

Artificial intelligence to detect tympanic membrane perforations.

OBJECTIVE: To explore the feasibility of constructing a proof-of-concept artificial intelligence algorithm to detect tympanic membrane perforations, for future application in under-resourced rural settings. METHODS: A retrospective review was conducted of otoscopic images analysed using transfer learning with Google's Inception-V3 convolutional neural network architecture. The 'gold standard' 'ground truth' was defined by otolaryngologists. Perforation size was categorised as less than one-third (small), one-third to two-thirds (medium), or more than two-thirds (large) of the total tympanic membrane diameter. RESULTS: A total of 233 tympanic membrane images were used (183 for training, 50 for testing). The algorithm correctly identified intact and perforated tympanic membranes (overall accuracy = 76.0 per cent, 95 per cent confidence interval = 62.1-86.0 per cent); the area under the curve was 0.867 (95 per cent confidence interval = 0.771-0.963). CONCLUSION: A proof-of-concept image-classification artificial intelligence algorithm can be used to detect tympanic membrane perforations and, with further development, may prove to be a valuable tool for ear disease screening. Future endeavours are warranted to develop a point-of-care tool for healthcare workers in areas distant from otolaryngology.

Building an Otoscopic screening prototype tool using deep learning.

BACKGROUND: Otologic diseases are often difficult to diagnose accurately for primary care providers. Deep learning methods have been applied with great success in many areas of medicine, often outperforming well trained human observers. The aim of this work was to develop and evaluate an automatic software prototype to identify otologic abnormalities using a deep convolutional neural network. MATERIAL AND METHODS: A database of 734 unique otoscopic images of various ear pathologies, including 63 cerumen impactions, 120 tympanostomy tubes, and 346 normal tympanic membranes were acquired. 80% of the images were used for the training of a convolutional neural network and the remaining 20% were used for algorithm validation. Image augmentation was employed on the training dataset to increase the number of training images. The general network architecture consisted of three convolutional layers plus batch normalization and dropout layers to avoid over fitting. RESULTS: The validation based on 45 datasets not used for model training revealed that the proposed deep convolutional neural network is capable of identifying and differentiating between normal tympanic membranes, tympanostomy tubes, and cerumen impactions with an overall accuracy of 84.4%. CONCLUSION: Our study shows that deep convolutional neural networks hold immense potential as a diagnostic adjunct for otologic disease management.

A rare case of primary inverted papilloma of the middle ear.

Inverted papilloma (IP) of the middle ear as a primary lesion or as an extension of a sinonasal papilloma, is extremely rare. Only 23 cases of primary inverted papilloma of the middle ear have been reported in the literature. They are locally aggressive tumours, with a high rate of recurrence and associated malignancy. We present a rare case of a 59-year-old man presenting with unilateral otorrhoea, tinnitus, and hearing loss. Otoscopy revealed posterior perforation filled by irregular budding neoformation. The temporal CT scan showed tissue filling the tympanic cavity as well as the mastoid antrum without bone lysis. The patient underwent limited tympanoplasty. An intraoperative biopsy of polypoid tissue filling the tymapanic cavity was made and histopathology showed an IP. A recurrence occurred 4 months after surgery. We performed open tympanoplasty allowing complete resection of the lesions, with no recurrence after a follow-up of 30 months.

Utility of a smartphone-enabled otoscope in the instruction of otoscopy and middle ear anatomy.

PURPOSE: To present the utility of a smartphone-enabled otoscope as a teaching adjunct in pre-clinical otoscopy training. METHODS: 60 pre-clinical medical students were randomized into either a control group using a conventional otoscope or an experimental group using a smartphone-enabled otoscope. Participants in each group were trained to use their assigned device and were given time to practice on a colleague's ear. Participants then completed a questionnaire indicating their ability to visualize anatomical landmarks of the middle ear as well as their confidence in performing a middle ear examination using their device. RESULTS: Compared to participants using the conventional otoscope, significantly more students using the smartphone-enabled otoscope identified the umbo (93% versus 63%, P = 0.005), the short process of the malleus (67% versus 33%, P = 0.008), the cone of light (100% versus 70%, P = 0.001), and the pars flaccida (60% versus 33%, P = 0.03). Furthermore, participants who used the smartphone-enabled otoscope reported significantly increased confidence in performing otoscopy compared to those who used a conventional otoscope (4.1 ± 0.7 versus 2.8 ± 0.9, P < 0.001). Finally, participants rated the smartphone-enabled otoscope as an excellent teaching aid for otoscopy training. CONCLUSION: The smartphone-enabled otoscope serves as a valuable teaching tool for pre-clinical otoscopy education. After using the device, pre-clinical students were more confident in performing a middle ear examination and in identifying important anatomical landmarks of the middle ear.

Principles of Pediatric Endoscopic Ear Surgery.

The article describes the unique benefits and challenges of transcanal (and transmastoid) endoscopic ear surgery (EES) for management of middle ear disease in children. It provides a rationale for EES in children and describes differences in anatomy between the pediatric and adult ear. The basic principles of EES, from operating room layout, choice of surgical instruments, and tips and pearls to avoid complications specific to the endoscope, are reviewed. Finally, techniques and outcomes in pediatric EES for tympanic membrane perforation, congenital cholesteatoma, and acquired cholesteatoma are summarized.

Petrous bone cholesteatoma: our experience of 51 patients with emphasis on cochlea preservation and use of endoscope.

Background: Petrous bone cholesteatoma (PBC) is a rare but local aggressive lesion which can lead to severe complications. Surgery is the mainstay for its treatment. Objectives: To analyse the clinical characteristics and surgical outcomes in a series of patients with PBC, paying special attention to cochlea preservation and use of endoscope. Materials and methods: Retrospective study of 51 patients with PBC who underwent surgery at our centre. Results: Hearing loss (72.5%) and facial paralysis (58.8%) were the two most common symptoms. According to Sanna's classification, supralabyrinthine subtype (51.0%) was the most common subtype, followed by the massive subtype (33.3%). In most patients, PBC was radically removed using subtotal petrosectomy (80.4%). Endoscope was used for assistance in six cases. Various managements of facial nerve were used in different cases. Hearing rehabilitation was not emphasized (44 postoperative dead ear); however, cochlea was preserved as far as possible (45.3%). Recurrence was identified in five patients by MRI with diffusion weighted imaging (DWI) sequence. No recurrence was detected in patients underwent surgery with endoscope assistance. Conclusions and significance: radical excision and functional reconstruction constitute the framework of PBC surgery. Cochlea preservation is critical for possible cochlear implantation in the future. Use of endoscope has the potential to enhance surgical precision and reduce recurrence.