A new 3D-printed temporal bone: 'the SAPIENS'-specific anatomical printed-3D-model in education and new surgical simulations.

PURPOSE: Otology and neuro-otology surgeries pose significant challenges due to the intricate and variable anatomy of the temporal bone (TB), requiring extensive training. In the last years 3D-printed temporal bone models for otological dissection are becoming increasingly popular. In this study, we presented a new 3D-printed temporal bone model named 'SAPIENS', tailored for educational and surgical simulation purposes. METHODS: The 'SAPIENS' model was a collaborative effort involving a multidisciplinary team, including radiologists, software engineers, ENT specialists, and 3D-printing experts. The development process spanned from June 2022 to October 2023 at the Department of Sense Organs, Sapienza University of Rome. Acquisition of human temporal bone images; temporal bone rendering; 3D-printing; post-printing phase; 3D-printed temporal bone model dissection and validation. RESULTS: The 'SAPIENS' 3D-printed temporal bone model demonstrated a high level of anatomical accuracy, resembling the human temporal bone in both middle and inner ear anatomy. The questionnaire-based assessment by five experienced ENT surgeons yielded an average total score of 49.4 ± 1.8 out of 61, indicating a model highly similar to the human TB for both anatomy and dissection. Specific areas of excellence included external contour, sigmoid sinus contour, cortical mastoidectomy simulation, and its utility as a surgical practice simulator. CONCLUSION: We have designed and developed a 3D model of the temporal bone that closely resembles the human temporal bone. This model enables the surgical dissection of the middle ear and mastoid with an excellent degree of similarity to the dissection performed on cadaveric temporal bones.

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.

3D 4K Exo-Endoscopic Temporal Bone Dissection: A Novel Approach for Sharing the Anatomy.

BACKGROUND: Temporal bone dissection is overwide recognized as an ideal training method for otologic surgeons. The knowledge of temporal bone anatomy and especially of the course of infratemporal facial nerve is pivotal in practice. The 3D exoscope is an innovative and promising tool, that was recently introduced in ear surgery. METHODS: A high-definition 3D exoscope (3D VITOM®) mounted on the VERSACRANETM holding system (Karl Storz) was used to perform two temporal bone dissection, with the aim to study the anatomy of infratemporal facial nerve. The 3D endoscope (TIPCAM®1 S 3D ORL, Karl Storz) was used in combination to provide a close-up high-quality view and to provide a different angle of view on fine anatomical relationships. RESULTS: The high-definition 3D exoscope allowed to conduct the dissection with high quality visualization and to share the same surgical field with trainees. Moreover, it showed a high interchangeability with the 3D endoscope. CONCLUSIONS: 3D 4 K Exo-endoscopic temporal bone dissection seems to have benefits in terms of educational purpose, especially concerning anatomy understanding. The superiority in teaching value of this tool should be further investigated in cohort studies.

[Online training for hearing implant surgery : A new approach to otological training. German version]. / Online-Training für Hörimplantatchirurgie : Ein neuer Ansatz in der otologischen Ausbildung.

OBJECTIVE: Education in microsurgery of the ear includes staged training to allow for mastering of the complex microsurgical procedures, particularly in the context of middle ear reconstruction and cochlear implantation. Traditional surgical training includes temporal bone preparations by cadaver dissection and supervised operating room practice. As these on-site trainings are limited, there is a need to broaden education facilities in an on-line format. Therefore, a first basic on-line training for otosurgery was developed. MATERIALS AND METHODS: The system consists of an artificial temporal bone model together with a set of basic surgical instruments and implant dummies. As an essential part of the training kit, a high-resolution camera set is included that allows for connection to a video streaming platform and enables remote supervision of the trainees' surgical steps by experienced otological surgeons. In addition, a pre-learning platform covering temporal bone anatomy and instrumentation and pre-recorded lectures and instructional videos has been developed to allow trainees to review and reinforce their understanding before hands-on practice. RESULTS: Over the three courses held to date, 28 participants with varying levels of prior surgical experience took part in this otological surgical training program. The immediate feedback of the participants was evaluated by means of a questionnaire. On this basis, the high value of the program became apparent and specific areas could by identified where further refinements could lead to an even more robust training experience. CONCLUSION: The presented program of an otosurgical online training allows for basal education in practical exercises on a remote system. In this way, trainees who have no direct access to on-site instruction facilities in ear surgery now have the chance to start their otosurgical training in an educational setting adapted to modern technologies.

Performance-optimized otoplasty.

OBJECTIVES: This study proposes a new surgical alternative for the most common deformity in the ears, the so-called "protruding/prominent ears", which is a condition that affects 5% of the Caucasian population (Goulart et al. in Rev Bras Cir Plast 26:602-607, 2011). This technique comes with the benefits of reduced surgical time, shallow learning curve, and a low revision rate. METHODS: We studied a total of 213 patients with an indication for otoplasty from January 2020 to January 2021. Women made up 65% of the study population, while men made up 35%, with an average age of 21 years, the youngest being 7 years of age. The technique presented here corrects all the deformities that cause protruding ears and can be performed together with other ear surgeries, such as surgical treatment of macrotia and lobuloplasty. All surgeries were performed in an outpatient setting under local anesthesia and sedation. RESULTS: All surgeries followed a performance-optimized protocol, with an average total surgical time of 45 min for a bilateral approach. Revision surgery was needed in 2% of cases, with the most frequent complaint being asymmetry in the upper third of the ears. The complication rate was approximately 7.5%, with 1 case of hematoma, 1 case of mild infection, 2 cases of altered ear sensitivity, 3 cases of keloid scar formation, 6 cases of asymmetry in the upper third of the ears, and 3 cases of irregularities or spikes in the antihelix cartilage. Patient satisfaction was measured using the McDowell/Wright Objectives and Outcome Index (McDowell in Plast Reconstr Surg 41:17-27). CONCLUSION: The proposed performance technique is a viable alternative to optimize the surgical time of otoplasty in an outpatient setting. This technique can be performed together with other corrective ear surgeries, has a shallow learning curve, and has a low revision rate. LEVEL IV: Evidence obtained from multiple time series with or without the intervention, such as case studies.

Acquisition of basic ear surgery skills: a randomized comparison between endoscopic and microscopic techniques.

BACKGROUND: Endoscopic ear surgery is gaining increasing popularity and has an important impact on teaching middle ear anatomy and basic surgical skills among residents and fellows. Due to the wide-angled views offered, the approach significantly differs from the established microscopic technique. This randomized study compares the acquisition of basic ear-surgery skills using the endoscopic and microscopic technique under standardized conditions. We aim to investigate the required surgical times, attempts and accidental damages to surrounding structures (errors) in surgeons with different training levels. METHODS: Final-year medical students (n = 9), residents (n = 14) and consultants (n = 10) from the Department of Otorhinolaryngology, Head and Neck Surgery at the University Hospital of Bern, Switzerland were enrolled in the present study. After randomization every participant had to complete a standard set of grasping and dissecting surgical tasks in a temporal bone model. After the first session the participants were crossed over to the other technique. RESULTS: Time required for completion of the surgical tasks was similar for both techniques, but highly dependent on the training status. A significant increase in the number of damages to the ossicular chain was observed with the microscopic as compared to the endoscopic technique (p < 0.001). Moreover, students beginning with the endoscopic technique showed an overall significantly lower amount of time to complete the tasks (p = 0.04). From the subjective feedback a preference towards the endoscopic technique mainly in medical students was observed. CONCLUSIONS: The endoscopic approach is useful and beneficial for teaching basic surgical skills, mainly by providing a reduction of damage to surrounding tissues with similar operating times for both techniques. Moreover, medical students performed significantly faster, when first taught in the endoscopic technique. Especially for young surgeons without previous training in ear surgery, the endoscope should be considered to improve surgical skills in the middle ear.

Improving resident familiarity with the translabyrinthine approach to the internal auditory canal.

OBJECTIVE: To increase otolaryngology resident experience with drilling and dissection of the internal auditory canal (IAC) via a translabyrinthine approach. STUDY DESIGN: Pilot study involving temporal bone education and drilling with completion of pre- and post-drilling surveys. METHODS: Participants observed an educational presentation on IAC anatomy and drilling, followed by manipulation of IAC nerves using a prosected cadaveric temporal bone. Participants then drilled the IAC and identified nerves using temporal bones with previously drilled mastoidectomies and labyrinthectomies. Pre- and post-drilling 5-point Likert-based surveys were completed. RESULTS: 7 participants were included in this study ranging in experience from PGY1 through PGY 5. The median number of times the IAC had been drilled previously was 0. Participants reported statistically significantly improved familiarity with the translabyrinthine approach after the session with median scores increasing from 2 to 3 (p=0.02), and a near-significant increase in familiarity with IAC anatomy with median scores increasing from 3 to 4 (p=0.06). Prior to the session, 71% of participants either disagreed or strongly disagreed that they had an idea of what the procedure would be like in a real operating room, whereas after the session 0% reported disagreement. 100% of participants were very satisfied with the overall experience. CONCLUSIONS: An educational session and temporal bone drilling experience using prosected bones significantly increased the reported familiarity with the translabyrinthine approach. Experiences such as this may enhance resident exposure to advanced lateral skull base approaches in a safe environment, and increase comprehension of the complex anatomic relationships of the IAC.

Computed tomography-based training model for otoplasty.

Otoplasty for the correction of protruding ears is characterized by various techniques and a common and popular cosmetic procedure. For the surgeon, whether beginner or advanced, it is essential to understand the principles and master techniques for standard auricular deformities before applying further sophisticated methods, because a lot of complications and failures are caused by wrong indication and incorrect surgical techniques. The different surgical steps are best learned from teaching models. Therefore, we developed two different silicone models of protruding ears with moderate auricular deformities: one with conchal hyperplasia for the training of conchal resection, and one without antihelix for creating an antihelical fold by suturing technique, based on computed tomography scans of patients. The silicone ear models were evaluated during four standardized surgery courses for residents in otorhinolaryngology by 91 participants using specially designed questionnaires. Nearly all participants rated the training on the auricular models as very helpful (n = 51) or good (n = 31); the scores for the different techniques and properties of the models ranged from 2.0 to 2.6 in a range from 1 (very good) to 4 (inadequate). The good results demonstrate the possibility for learning different surgical otoplasty techniques with this newly designed teaching tool.

A review of simulation platforms in surgery of the temporal bone.

BACKGROUND: Surgery of the temporal bone is a high-risk activity in an anatomically complex area. Simulation enables rehearsal of such surgery. The traditional simulation platform is the cadaveric temporal bone, but in recent years other simulation platforms have been created, including plastic and virtual reality platforms. OBJECTIVE OF REVIEW: To undertake a review of simulation platforms for temporal bone surgery, specifically assessing their educational value in terms of validity and in enabling transition to surgery. TYPE OF REVIEW: Systematic qualitative review. SEARCH STRATEGY: Search of the Pubmed, CINAHL, BEI and ERIC databases. EVALUATION METHOD: Assessment of reported outcomes in terms of educational value. RESULTS: A total of 49 articles were included, covering cadaveric, animal, plastic and virtual simulation platforms. Cadaveric simulation is highly rated as an educational tool, but there may be a ceiling effect on educational outcomes after drilling 8-10 temporal bones. Animal models show significant anatomical variation from man. Plastic temporal bone models offer much potential, but at present lack sufficient anatomical or haptic validity. Similarly, virtual reality platforms lack sufficient anatomical or haptic validity, but with technological improvements they are advancing rapidly. CONCLUSIONS: At present, cadaveric simulation remains the best platform for training in temporal bone surgery. Technological advances enabling improved materials or modelling mean that in the future plastic or virtual platforms may become comparable to cadaveric platforms, and also offer additional functionality including patient-specific simulation from CT data.

Multi-material 3D Models for Temporal Bone Surgical Simulation.

HYPOTHESIS: A simulated, multicolor, multi-material temporal bone model can be created using 3-dimensional (3D) printing that will prove both safe and beneficial in training for actual temporal bone surgical cases. BACKGROUND: As the process of additive manufacturing, or 3D printing, has become more practical and affordable, a number of applications for the technology in the field of Otolaryngology-Head and Neck Surgery have been considered. One area of promise is temporal bone surgical simulation. METHODS: Three-dimensional representations of human temporal bones were created from temporal bone computed tomography (CT) scans using biomedical image processing software. Multi-material models were then printed and dissected in a temporal bone laboratory by attending and resident otolaryngologists. A 5-point Likert scale was used to grade the models for their anatomical accuracy and suitability as a simulation of cadaveric and operative temporal bone drilling. RESULTS: The models produced for this study demonstrate significant anatomic detail and a likeness to human cadaver specimens for drilling and dissection. CONCLUSION: Simulated temporal bones created by this process have potential benefit in surgical training, preoperative simulation for challenging otologic cases, and the standardized testing of temporal bone surgical skills.

[The problems of education in otosurgery: the current state-of-the-art].

An overview of the current problems of education in ear surgery is presented. The methods used for the purpose including the classical dissection of the temporal bone, application of synthetic and natural (animal) temporal bones are described alongside with the 3D models of the temporal bone and virtual dissection. In addition, the review covers the problem of enhancing effectiveness of the teaching methods, considers their advantages and disadvantages.

[The new complex multimedia program for the training in otosurgery].

The objective of the present study was to develop the complex program for the training in otosurgery. The proposed complex program for teaching surgical procedures on the ear is described. The program consists of two steps, preparation and dissection. The first stage is designed to prepare the learner surgeons for dissection with the use of the teaching materials "Manipulations on the temporal bone" and the 3D model of the temporal bone. At the second stage, the learners perform successively two tasks: dissection of an artificial and cadaveric bones with the maximum possible number of surgical procedures on each bone. The aforementioned teaching materials and 3D model of the temporal bone are used at the dissection stage too.

Modern Trends in Otologic Surgery and Implications for Residency Training.

OBJECTIVE: Placing a middle ear prosthesis is considered a key competency for the general otolaryngologist, but surgeons struggle to obtain and maintain this skill. The current study aims to characterize pre-coronavirus disease 2019 trends in stapedectomy and ossiculoplasty. STUDY DESIGN: Database review. SETTING: Tricare beneficiaries are treated at civilian and military facilities. METHODS: The Department of Defense beneficiary population of more than nine million persons per year was reviewed for patients undergoing either stapedectomy or ossiculoplasty between 2010 and 2019, identified by the current procedural terminology code. RESULTS: A total of 3052 stapedectomies and 7197 ossiculoplasties were performed. Over the 10-year study period, stapedectomy decreased by 23%, with an average annual rate of -2.7% per year (Pearson r = -.91, P = .0003). Ossiculoplasties declined by 18%, an average annual rate of -1.9% (r = -.8, P = .006). In combination, cases declined by 20%, an average annual rate of -2.2% (r = -.87, P = .001). CONCLUSION: While declines in stapedectomy surgery have been well reported, here we show steady declines in ossiculoplasty as well. If these trends continue, more cochlear implantations may be performed annually than stapedectomy and ossiculoplasty combined, with cochlear implantation likely to overtake ossicular chain surgery in the near future. These changes in surgical volume have a direct implication on resident education and general otolaryngology expectations after graduation. Strong consideration should be made to replace "Stapedectomy/Ossiculoplasty" as resident key indicator with "Cochlear Implantation," a more professionally meaningful skill.

The learning curve in revision cholesteatoma surgery.

OBJECTIVE: To review the results of revision surgery for cholesteatoma. STUDY DESIGN: Retrospective review of patient's records. SETTING: Tertiary referral center. PATIENTS: A retrospective study of patients operated for acquired middle ear cholesteatoma during the period 1990-2002 was performed. A total of 758 patients were divided into two groups according to surgical experience, and followed during short-term and long-term period. The cholesteatoma was divided according to location, age of patients, status of auditory ossicles, and bilaterality of disease. INTERVENTIONS: The patients were treated with single canal wall up or wall down, according to the propagation of disease and condition of middle ear. The indications for the reoperations were: recurrent or residual cholesteatoma, resuppuration, and AB gap more than 20 dB. MAIN OUTCOME MEASURES: Type of surgical therapy, localization of cholesteatoma, age of patients, revisions, bilaterality of disease, damage of auditory ossicles and learning curve were analyzed. RESULTS: The number of revision operations was reduced in the second period (from totally 24.3% to 16.4%). Closed technique gave a significantly lower rate of failure. For attic cholesteatoma, adults, bilateral disease, and ossicular damage the rate of revisions was significantly lower with surgical experience. CONCLUSION: Surgical experience was important for reduction of reoperation rate for attic and sinus cholesteatoma, adults, bilateral cholesteatoma, and when closed technique is used.

A new temporal bone and cadaver head holder for temporal bone surgical technique training.

OBJECTIVE: To design a new temporal bone and cadaver head holder, overcoming the drawbacks of the bowl-type holder and other existing holders for dissection, and thereby benefiting training and research on temporal bone surgery. MATERIALS AND METHODS: We designed and fabricated a novel holder with a horizontal arm that can be connected with an object holder specific for the temporal bone or a three-pin fixture specific for cadaver heads. A separate hand support helps to stabilize the hand during examinations on the temporal bone and skull base. RESULTS: The use of the temporal bone and cadaver head holder by 30 trainees during our temporal bone surgical technique courses held by the Department of Otolaryngology, Peking Union Medical College Hospital (PUMCH) worked better than other holders and saved laboratory time. It has become the standard equipment of the Temporal Bone Laboratory of PUMCH. CONCLUSIONS: The temporal bone and cadaver head holder we describe is compact, stable and easily adjustable. It offers considerable advantages to trainees.

Defining the Learning Curve for Endoscopic Ear Skills Using a Modular Trainer: A Multi-Institutional Study.

OBJECTIVE: Quantify the learning curve for endoscopic ear skills acquisition in otolaryngology residents using a simulator. The secondary objective was to determine if demographic factors or previous endoscopic experience influenced skill development. STUDY DESIGN: Prospective, multicenter study. Resident participants each completed 10 amassed trials using a validated endoscopic ear skill trainer. SETTING: Two academic teaching hospitals. SUBJECTS: Otolaryngology residents. MAIN OUTCOME MEASURES: Trial completion times; rate of improvement over time. RESULTS: Thirty-eight residents completed the study, 26 from program A and 12 from program B. Fifteen participants were women and 23 were men. Mean age was 30 years old (range 26 to 34 years). Previous experience with otoendoscopy (B = -16.7, p = 0.005) and sinus endoscopy (B = -23.4, p = 0.001) independently correlated with lower overall trial times. Age, gender, postgraduate year, handedness, interest in otology, and video gaming were not associated with trial times. On multivariate logistic regression, resident completion times improved with trial number, and residents without previous endoscopy experience improved at a faster rate than those with experience ( p < 0.001). CONCLUSIONS: Novice surgeons may acquire basic endoscopic ear experience with self-directed simulation training. The learning curve for transcanal endoscopic ear surgery is comparable to those demonstrated for other otologic surgeries, and specific task competencies can be achieved within 10 trials, suggesting that previous experiences, or lack thereof, may not dictate the ability to acquire new skills. There may be a translational value to previous endoscopic sinus experience on learning transcanal endoscopic ear surgery.

Teaching Otolaryngology skills through simulation.

Over the last couple of decades, learning through simulation has become popularised for various reasons and is continuing to expand exponentially despite a lack of robust evidence that it actually improves outcomes for patients and learners. There has been a particular growth in the use of high-fidelity virtual reality simulators for surgical training as the technology has become more affordable. In the field of Otolaryngology, simulation appears to help teach simple procedural skills through to complex surgery of the temporal bone and paranasal sinuses. This is happening in an era when quality of care and patient safety are top of the agenda and cadaveric material is in short supply. In this article, we explore the history behind simulation, review the available evidence and discuss its applications within Otolaryngology.

Does microscopic experience influence learning curve in endoscopic ear surgery? A multicentric study.

OBJECTIVE: The aim of the present study was to illustrate the learning curve of endoscopic type-1 tympanoplasty comparing experts in microscopic otology versus neophyte surgeons. METHODS: Eight ear surgeons, from tertiary referral centers, who had performed at least 30 endoscopic type 1 tympanoplasties were included in the study. Demographic data and medical records regarding the first 30 endoscopic type-1 tympanoplasties were retrospectively collected by each surgeon. A 14-questions survey focused on subjective aspects of the learning curve was administered. Surgeons were divided in two groups: one with previous experience in microscopic ear surgery (group 1) and one with no previous experience in ear surgery (group 2). The learning curve of endoscopic type 1 tympanoplasty was compared between the groups. RESULTS: Mean surgical time was 89.2 min in group 1 vs. 79.5 min in group 2 (p < 0.01). When divided in 5 surgeries-steps, the only significant difference was appreciated in the first 5 surgeries with a longer mean time in group 1 vs. group 2 (+28.4 min; p < 0.05). CONCLUSIONS: Surgeon's previous experience may influence the EES learning curve. Our results show that the first 5 surgical procedures are more challenging for surgeons experienced in microscopic surgery, subsequently the curve progression improves sharply and appears reversing the initial trend by the end of the 30 surgeries.

Operable, Low-Cost, High-Resolution, Patient-Specific 3D Printed Temporal Bones for Surgical Simulation and Evaluation.

OBJECTIVES: Three-dimensional printed models created on a consumer level printer can be used to practice mastoidectomy and to discern mastoidectomy experience level. Current models in the literature for mastoidectomy are limited by expense or operability. The aims of this study were (1) to investigate the utility of an inexpensive model for mastoidectomy and (2) to assess whether the model can be used as an evaluation tool to discern the experience level of the surgeon performing mastoidectomy. METHODS: Three-dimensional printed temporal bone models from the CT scan of a 7-year old patient were created using a consumer-level stereolithography 3D printer for a raw material cost of $10 each. Mastoidectomy with facial recess approach was performed by 4 PGY-2 residents, 4 PGY-5 residents, and 4 attending surgeons on the models who then filled out an evaluation. The drilled models were collected and then graded in a blinded fashion by 6 attending otolaryngologists. RESULTS: Both residents and faculty felt the model was useful for training (mean score 4.7 out of 5; range: 4-5) and case preparation (mean score: 4.3; range: 3-5). Grading of the drilled models revealed significant differences between junior resident, senior resident, and attending surgeon scores (P = .012) with moderate to excellent interrater agreement (ICC = 0.882). CONCLUSION: The described operable model that is patient-specific was rated favorably for pediatric mastoidectomy case preparation and training by residents and faculty. The model may be used to differentiate between experience levels and has promise for use in formative and summative evaluations.

Teaching Endoscopic Ear Surgery.

Endoscopic ear surgery (EES) has become an integral part of otologic surgery. Training in EES involves learning fundamental techniques for endoscopic visualization, becoming proficient at one-handed dissection, mastering use of instruments designed for endoscopic ear surgery, and learning to optimize the operating room setup specifically for EES. Despite the steep learning curve, EES offers several advantages over the microscope for otologic procedures. With the rise in the demand for minimally invasive approaches, EES has a clear role in the future of otologic surgery. Identifying strategies to improve the training process of EES for the novice and experienced otolaryngologist is paramount.