Dissection Training Research Articles

The path to advancement in endoscopic ear surgery

Endoscopic ear surgery is currently widely applied in middle ear and lateral skull base procedures, driving the development of ear surgery towards minimally invasive approaches and function preservation. Endoscopic techniques offer many advantages. However, the learning curve is relatively steep, requiring surgeons to overcome challenges such as single-handed operation and a lack of spatial awareness. Through in-depth theoretical study, temporal bone dissection training, and gradual surgical practice, this technique can be gradually mastered. The combined use of endoscopy and microscopy further enhances the flexibility and precision of lateral skull base surgeries. Repeated cycles of anatomical study, observation, and practice, along with timely updates in knowledge and skills, lay the foundation for improving the outcomes of endoscopic ear surgery.

Development and Assessment of a High-Fidelity Simulator for the Microsurgical Dissection of the Sylvian Fissure

BackgroundThe dissection of the Sylvian fissure (SF) is a crucial technique requiring considerable expertise and skills traditionally acquired through years of experience. The continous decline in surgical case-load necessitates the development of efficient alternative training opportunities. However, building a realistic and effective training simulator for the microsurgical dissection of the SF as an integral part of the neurosurgical curriculum, remains a challenging endeavor. This work aims to develop and evaluate a high-fidelity phantom simulator for effective and transferable training of the SF dissection with a focus on middle cerebral artery aneurysm clipping. MethodsA phantom simulator replicating the anatomy and tactile properties of the human skull, brain and meninges was developed incorporating additive manufacturing, neurosurgical expertise, and tissue engineering. Neurosurgical residents and experienced vascular neurosurgeons (n = 16) tested and rated the simulator’s face and content validities and answered questions on the model’s educational usefulness. ResultsThe resulting Sylvian fissure model is anatomically and haptically faithful, reusable and modifiable. The simulator overwhelmingly received positive ratings in face and content validity, with mean scores of 4.8 and 4.7 out of 5, respectively. Neurosurgeons deemed the simulator as highly accurate in respect to anatomical and tactile accuracy. Neurosurgical residents and neurosurgeons rated the simulator as superior in comparison to traditional teaching and training mehtods. ConclusionsThe presented methodology demonstrates that the development and assessment of a high-fidelity hands-on simulator for the focused training of one of the most delicate neurosurgical procedures is achievable in a timely manner and without extensive investments.

Effectiveness of a novel ex vivo training model for gastric endoscopic submucosal dissection training: a prospective observational study conducted at a single center in Japan.

The efficacy of endoscopic submucosal dissection (ESD) for early-stage gastric cancer is well established. However, its acquisition is challenging owing to its complexity. In Japan, G-Master is a novel ex vivo gastric ESD training model. The effectiveness of training using G-Master is unknown. This study evaluated the efficacy of gastric ESD training using the G-Master to evaluate trainees' learning curves and performance. Four trainees completed 30 ESD training sessions using the G-Master, and procedure time, resection area, resection completion, en-bloc resection requirement, and perforation occurrence were measured. Resection speed was the primary endpoint, and learning curves were evaluated using the Cumulative Sum (CUSUM) method. All trainees completed the resection and en-bloc resection of the lesion without any intraoperative perforations. The learning curves covered three phases: initial growth, plateau, and late growth. The transition from phase 1 to phase 2 required a median of 10 sessions. Each trainee completed 30 training sessions in approximately 4 months. Gastric ESD training using the G-Master is a simple, fast, and effective method for pre-ESD training in clinical practice. It is recommended that at least 10 training sessions be conducted.

Immersive Photorealistic Three-Dimensional Neurosurgical Anatomy of the Cerebral Arteries: A Photogrammetry-Based Anatomic Study.

Neurosurgeons need a profound knowledge of the surgical anatomy of the cerebral arteries to safely treat patients. This is a challenge because of numerous branches, segments, and tortuosity of the main blood vessels that supply the brain. The objective of this study was to create high-quality three-dimensional (3D) anatomic photorealistic models based on dissections of the brain arterial anatomy and to incorporate this data into a virtual reality (VR) environment. Two formaldehyde-fixed heads were used. The vessels were injected with radiopaque material and colored silicone and latex. Before the dissections, the specimens were computed tomography scanned. Stratigraphical anatomic dissection of the neck and brain was performed to present the relevant vascular anatomy. A simplified surface scanning method using a mobile phone-based photogrammetry application was used, and the data were incorporated into a VR 3D modeling software for post-processing and presentation. Fifteen detailed layered photorealistic and two computed tomography angiography-based 3D models were generated. The models allow manipulation in VR environment with sufficient photographic detail to present the structures of interest. Topographical relevant anatomic structures and landmarks were annotated and uploaded for web-viewing and in VR. Despite that the VR application is a dedicated 3D modeling platform, it provided all necessary tools to be suitable for self-VR study and multiplayer scenarios with several participants in one immersive environment. Cerebral vascular anatomy presented with photogrammetry surface scanning method allows sufficient detail to present individual vessel's course and even small perforating arteries in photorealistic 3D models. These features, including VR visualization, provide new teaching prospects. The whole study was done with simplified algorithms and free or open-source software platforms allowing creation of 3D databases especially useful in cases with limited body donor-based dissection training availability.

Development of a colonic endoscopic submucosal dissection training model that simulates respiratory movements.

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Effectiveness of Strategy-Focused Training in Colorectal Endoscopic Submucosal Dissection: A Retrospective Observational Study.

Colorectal ESD, an advanced minimally invasive treatment, presents technical challenges, with globally varying training methods. We analyzed the learning curve of ESD training, emphasizing preoperative strategies, notably gravity traction, to guide ESD instructors and trainee programs. This retrospective study included 881 cases guided by an experienced supervisor. Six trainees received "strategy-focused" instruction. To evaluate the number of ESD experiences in steps, the following phases were classified based on ESD experiences of each trainees: Phase 0 (0-50 ESD), Phase 1 (51-100 ESD), Phase 2 (101-150 ESD), and Phase 3 (151-200 ESD). Lesion background, outcomes, and safety were compared across phases. Factors contributing to technical difficulty in early (Phase 0 and 1) and late phases (Phase 2 and 3) were identified, along with the utility of traction ESD with device assistance. Treatment outcomes were favorable, with 99.8% and 94.7% en bloc resection and curative resection rates, respectively. Approximately 90% self-completion rate could be achieved after experiencing about 50 cases (92.7% in Phase 1), signifying proficiency growth despite increased case difficulty. In early phases, factors such as left-sided colon, LST-NG morphology, and severe fibrosis pose challenges. In late phases, LST-NG morphology, mild and severe fibrosis remained significant. Traction-assisted ESD, utilized in 3% of cases, comprised planned (1.1%) and rescue (1.9%) methods. Planned traction aided specific lesions, while rescue traction was common in the right colon. "Strategy-focused" ESD training consistently yields successful outcomes, effectively adapting to varying difficulty factors in different proficient stages.

Novel gastric endoscopic submucosal dissection training model enhances the endoscopic submucosal dissection skills of trainees: a multicenter comparative study.

Endoscopic submucosal dissection (ESD) requires high endoscopic technical skills, and trainees should develop effective training methods. In collaboration with KOTOBUKI Medical, we developed the G-Master, which is a non-animal training model that can simulate various parts of gastric ESD. We aimed to clarify the usefulness of the G-Master for inexperienced ESD trainees. We collected data from the first 5 gastric ESD cases conducted by 15 inexperienced ESD trainees at 5 participating centers between 2018 and 2022. The participants were divided into two groups: the G-Master training and non-G-Master training groups. Outcome measurements, such as procedural speed, perforation rate, self-completion rate, and en bloc resection rate, were compared between the two groups retrospectively. A total of 75 gastric ESD cases were included in this study. The G-Master training group included 25 cases performed by 5 trainees, whereas the non-G-Master training group included 50 cases performed by 10 trainees. The median procedural speed for all cases was significantly faster in the G-Master training group than in the non-G-Master training group. Moreover, the procedural speed was linearly improved from the initial to the last cases in the lower location in the G-Master training group compared with the non-G-Master training group. In addition, although there was no significant difference, the G-Master training group showed lower rates of perforation and a lesser need to transition to expert operators than the non-G-Master training group. The G-Master could improve the ESD skills of inexperienced ESD trainees.

Virtual reality simulators for temporal bone dissection: overcoming limitations of previous models

Temporal bone dissection is a critical skill for otolaryngology trainees: however, it is challenging to master due to the complex anatomy and limited exposure to cadaveric specimens. The aim of this review was to develop and evaluate a novel virtual reality (VR) simulator for temporal bone dissection, addressing the limitations of previous simulators reported in the literature. A comprehensive literature search was conducted in the PubMed, Embase, and Cochrane Library databases from inception to September 2022. The search was limited to studies that evaluated the effectiveness of VR simulators for temporal bone dissection. The quality of the included studies was assessed using the Cochrane Risk of Bias Tool. The results showed that VR simulators can significantly improve temporal bone dissection skills, including anatomical knowledge, instrument handling, and surgical performance. Compared to traditional training methods, VR simulation was associated with faster learning curves, better retention of skills, and greater confidence among trainees. However, some limitations of current VR models were identified, including the lack of haptic feedback, limited realism, and short duration of practice. VR simulators are a valuable adjunct to traditional methods for temporal bone dissection training. The recently developed VR simulator addressed the limitations of previous simulators and demonstrated its potential to enhance the training of clinicians in temporal bone dissection. Future directions for research include further validation of the simulator and exploration of its potential for use in clinical settings.

3D printed headholder for use in neurosurgical cadaver training: Technical note

IntroductionHeadholders or skull clamps serve as indispensable tools in neurosurgery, facilitating the precise positioning and stabilization of the head for surgery. The realm of neurosurgical training in cadaver labs presents a clear challenge due to the lack of suitable non-clinical headholders. Research questionWe describe a 3D printed stainless-steel headholder for use in neurosurgical cadaver lab training. Material and methodsComputer-aided design software was used to design a headholder, utilizing a three-pin skull fixation. Through an iterative process involving a plastic 3D printed prototype, ultimately a robust model was manufactured using a 3D stainless-steel printer. ResultsThe headholder was fixed to a multi-angle adjustable vise, enabling optimal positioning to support simulation of neurosurgical approaches and dissection training by neurosurgical residents and staff in the cadaver lab. Discussion and conclusionThis custom-made headholder offers an effective solution for secure fixation of cadaver skulls during neurosurgical training, contributing to practicality and efficiency in cadaver dissection. Despite the lack of evidence-based guidelines for neurosurgical headholder use, this device provides a valuable tool for neurosurgical trainees to practice proper placement, understand associated complications, and improve their hands-on skills. The digitally available 3D model can be optimized, shared, and further improved by other neurosurgical units and trainees, fostering collaborative advancements in neurosurgical training.

Novel quantitative assessment indicators for efficiency and precision of endoscopic submucosal dissection in animal training models by analyzing an electrical surgical unit.

Although endoscopic submucosal dissection (ESD) training is important, quantitative assessments have not been established. This study aimed to explore a novel quantitative assessment system by analyzing an electrical surgical unit (ESU). This was an ex vivo study. Step one: to identify the novel efficiency indicators, 20 endoscopists performed one ESD each, and we analyzed correlations between their resection speed and electrical status. Step two: to identify the novel precision indicators, three experts and three novices performed one ESD each, and we compared the stability of the electrical status. Step three: three novices in step two performed 19 additional ESDs, and we analyzed the learning curve using novel indicators. Step one: the percentage of total activation time (AT) of ESU in the procedure time (β coefficient, 0.80; P < 0.01) and AT required for submucosal dissection (β coefficient, -0.57; P < 0.01) were significantly correlated with the resection speed. Step two: coefficient of variation of the AT per one pulse (0.16 [range, 0.13-0.17] vs. 0.26 [range, 0.20-0.41], P = 0.049) and coefficient of variation of the peak electric power per pulse during mucosal incision (0.14 [range, 0.080-0.15] vs. 0.25 [range, 0.24-0.28], P = 0.049) were significantly lower in the experts than in the novices. Regarding the learning curve, thepercentage of total AT of ESU in the procedure time and ATrequired for submucosal dissection had a trend of improvement. Novel indicators identified by analyzing ESU enable quantitative assessment for endoscopist's skill.

Development of a novel colorectal endoscopic submucosal dissection training model.

Colorectal endoscopic submucosal dissection (ESD) requires technically advanced endoscopic skill. To improve endoscopic skills, animals or their extracted digestive tracts are used for ESD training [1] [2] [3], which raises several issues regarding ethics, cost, and infection.

Feasibility and safety of Heavy Lifting Strength Training in Head and Neck Cancer survivors post-surgical neck dissection (the LIFTING trial).

Light-to-moderate intensity strength training (LMST) improves muscular strength, physical functioning, and some side effects in head and neck cancer survivors (HNCS). Heavy lifting strength training (HLST) may further improve these outcomes; however, it has not been studied in HNCS. The primary aim of the LIFTING trial was to examine the feasibility and safety of a HLST program in HNCS ≥1-year post-surgical neck dissection. In this single-arm feasibility study, HNCS were asked to complete a twice weekly, 12-week, supervised HLST program, gradually progressing to lifting heavy loads of 80-90% of 1 repetition maximum (1RM) for barbell squat, bench press, and deadlift. The feasibility outcomes included recruitment rate, 1RM completion rate, program adherence, barriers, and motivation. The preliminary efficacy outcomes included changes in upper and lower body strength. Nine HNCS were recruited over an 8-month period during the COVID-19 pandemic. All 9 (100%) completed the 1RM tests and successfully progressed to heavy loads at approximately 5 weeks. The median attendance was 95.8% (range 71-100%), and few barriers were reported. Weight lifted increased for squat/leg press (median change: +34kg; 95% CI +25 to +47), bench press (median change: +6kg; 95% CI +2 to +10), and deadlift (median change: +12kg; 95% CI +7 to +24). No adverse events were reported and participants were motivated to continue HLST after the study. HLST appears feasible and safe for HNCS and may result in meaningful improvements in muscular strength. Future research should consider additional recruitment strategies and compare HLST to LMST in this understudied survivor population. NCT04554667.

Usefulness of a new polyvinyl alcohol hydrogel (PVA-H)-based simulator for endoscopic submucosal dissection training: a pilot study.

We developed a new endoscopic submucosal dissection (ESD) simulator and evaluated its efficacy and realism for use training endoscopists. An ESD simulator was constructed using polyvinyl alcohol hydrogel sheets and compared to a previous ESD simulator. Between March 1, 2020, and December 30, 2021, eight expert endoscopists from three different centers analyzed the procedure-related factors of the simulator. Five trainees performed gastric ESD exercises under the guidance of these experts. Although the two ESD simulators provided overall favorable outcomes in terms of ESD-related factors, the new simulator had several benefits, including better marking of the target lesion's limits (p<0.001) and overall handling (p<0.001). Trainees tested the usefulness of the new ESD simulator. The complete resection rate improved after 3 ESD training sessions (9 procedures), and the perforation rate decreased after 4 sessions (12 procedures). We have developed a new ESD simulator that can help beginners achieve a high level of technical experience before performing real-time ESD procedures in patients.

Conduct of body donation and cadaveric dissection training during the COVID-19 pandemic: challenges, impacts and mitigation.

The new coronavirus disease 2019 (COVID-19) has had a substantial impact on the Silent Mentor Programme (SMP), a programme in which members of the public may pledge their bodies to be used for medical training and research after their death. This study aimed to explore the conduct of body donations and simulation surgery training during the COVID-19 pandemic from the viewpoints of the committee members of the SMP and the next-of-kin of body donor pledgers. This study utilised a qualitative exploration method to seek an in-depth understanding of this phenomenon. In-depth individual interviews were carried out. Thematic analysiswas used to identify patterns of themes. The COVID-19 polymerase chain reaction (RT-PCR) test is compulsory before accepting a body donation, and this resulted in the turning down of several donations. Being a donor is the final wish of pledgers and this turning down led to a negative emotional remorseful feeling in the next-of-kin of pledgers. From the perspective of students, it is feared that the conduct of the programme, particularly the home visit session being held online, has impeded teaching of humanistic values, compassion, and empathy, which is the prime philosophy of the programme. Previous to the pandemic, the programme ceremonies were well-attended, denoting the utmost respect and recognition of the mentors; however, travel restrictions due to the pandemic limiting in-person attendance resulted in ceremonies becoming less impactful. Continuous postponements of cadaveric dissection training also resulted in students missing training opportunities, hence potentially impairing their professional practice and humanistic values in the medical profession. Counselling interventions should be directed at easing the negative psychologicalimpacton the next-of-kin of pledgers. As the COVID-19 pandemic may pose a significant impediment to achieving the educational outcomes of cadaveric dissection training, efforts to make up for these gaps are essential.

Endoscopic submucosal dissection training: evaluation of an ex vivo training model with continuous perfusion (ETM-CP) for hands-on teaching and training in China

BackgroundThe existing ex vivo models of endoscopic submucosal dissection (ESD) cannot simulate intraoperative hemorrhage well. We aimed to establish an ESD training method by applying an ex vivo training model with continuous perfusion (ETM-CP).MethodsFour training sessions were conducted for 25 novices under the guidance of 2 experts. Eventually, 10 novices completed ESD operations on a total of 89 patients after the training. The resection effectiveness, resection speed, complication rate, and novice performance before and after the training were compared. The data regarding the effects of the training and the model were gathered through a questionnaire survey.ResultsIn terms of the simulation effect of the model, ETM-CP was evaluated as similar to the live pig in all aspects (P > 0.05). The questionnaire analysis revealed that the ESD theoretical knowledge, skill operation, and self-confidence of novices were improved after the training (P < 0.05). The resection time per unit area had a correlation with the number of training periods (rs = – 0.232). For novice performance, the resection time per unit area was shortened (P < 0.05). There was no difference in patient performance between the novice group and the expert group after the training in terms of en bloc resection, R0 resection, complication rate, endoscopic resection bleeding (ERB) score, muscularis propria injury (MPI) score, and resection time per unit area (P > 0.05).ConclusionThe ETM-CP is effective for ESD training.

Virtual Reality and Augmented Reality in Anatomy Education During COVID-19 Pandemic.

The pandemic of COVID-19 has radically changed the anatomy education approaches. This happens because medical students, due to the necessity of remote education, didn't have access to cadavers, which was the principal method of dissection training. Circumstances like these encouraged the health care providers to innovate new teaching methods with the help of virtual and augmented reality to outdistance the restrictions. This review aims to examine the pioneer technological and educational tools and their usage in the future. Detailed research was performed via the PubMed database using the following keywords "Virtual Reality (VR),Augmented Reality (AR),Anatomy Education, and COVID-19". No further filters were used. All the existing evidence suggests that the vast majority was negatively affected by the COVID-19 era. Using new technological methods in anatomy training could not effectively replace the absence of the traditionally used teaching methods like dissection, prosection, and lectures by physical presence. Although the new digital anatomy teaching approaches seem to be very promising, it is not clear if they can fully replace the traditional anatomy education methods.

The feasibility of virtual reality for anatomic training during temporal bone dissection course

Introduction: In recent decades, the lack of educational resources for cadaveric dissections has complicated the hands-on otological surgical training of otorhinolaryngology residents due to the poor availability of cadaver temporal bones, facilities, and limited hours for practice. Since students must gain adequate and patient-safe surgical skills, novel training methods need to be considered. In this proof-of-concept study, a new virtual reality (VR) software is described; this was used during a national temporal bone dissection course where we investigated its feasibility for otological surgical training.Methods: A total of 11 otorhinolaryngology residents attended the annual 2-day hands-on temporal bone dissection course; they were divided into two groups with similar experience levels. Both groups received a lecture on temporal bone anatomy. A total of 22 cadaver temporal bones were harvested for the course; 11 of these bones were imaged by computed tomography. VR software designed for preoperative planning was then used to create 3D models of the imaged temporal bones. Prior to dissection training, the first group underwent a 30-min VR session, where they identified 24 surgically relevant anatomical landmarks on their individual temporal bone. The second group proceeded directly to dissection training. On the second day, the groups were switched. The feasibility of VR training was assessed with three different metrics: surgical performance evaluation using a modified Hopkins objective structured assessment of technical skill (OSATS), time for the surgical exposure of anatomical landmarks, and the user experience collected with a Likert scale questionnaire.Results: No differences were noted in the overall performance between the groups. However, participants with prior VR training had a lower mean time for surgical exposure of anatomical landmarks (antrum 22.09 vs. 27.64 min, p = 0.33; incus 60.00 vs. 76.00, p = 0.03; PSCC 71.83 vs. 88.50, p = 0.17) during dissection training. The participants considered VR beneficial for anatomy teaching, surgery planning, and training.Conclusion: This study demonstrated the feasibility of implementing VR training in a temporal bone dissection course. The VR training demonstrated that even short expert-guided VR sessions are beneficial, and VR training prior to the dissections has a positive effect on the time needed to perform surgical tasks while maintaining comparable performance scores.

Development of new gastric endoscopic submucosal dissection training model: A reproducibility evaluation study

Background and study aims Gastric endoscopic submucosal dissection (ESD) is a highly technical procedure mainly due to the distinctive shape of the stomach and diverse locations of lesions. We developed a new gastric ESD training model (G-Master) that could accurately recreate the location of the stomach and assessed the reproducibility of located lesions in the model. Methods The model comprises a simulated mucous membrane sheet made of konjac flour and a setting frame, which can simulate 11 locations of the stomach. We assessed the reproducibility of each location in the model by assessing the procedure speed and using a questionnaire that was distributed among experts. In the questionnaire, each location was scored on a six-point scale for similarity of locations. Results The mean score for all locations was high with > 4 points. Regarding locations, lower anterior and posterior walls had medium scores with 3 to 4 points. The procedure speed was slower in the greater curvature of the upper and middle gastric portions, where ESD is considered more difficult than the overall procedure speed. Conclusions The new gastric ESD training model appears to be highly reproducible for each gastric location and its application for training in assuming actual gastric ESD locations.

Cadaver dissection for oculoplastic procedures: A beginner's guide.

The purpose of this article is to form a basic guide for beginning the cadaver dissection training programs focused on oculoplastic surgical procedures. Ours was a collaborative study between the departments of Ophthalmology and Anatomy in a tertiary care teaching institute. We formed a step-wise approach to begin the cadaver dissection focused on the oculoplastic surgical procedures. The basics of cadaver procurement, processing, and preparation for dissections were described. The operative requirements of trainees, surgical handling of cadavers, and basic oculoplastic surgical steps were discussed. The types of embalming (cadaver preservation process) and steps have been described in detail. We have emphasized the preoperative discussion about the proposed dissections using standard teachings and skull models for easier understanding. Additional helping tools like soft embalming and injectable substances for better intra-dissection understanding (intra-arterial, intravenous and orbital injections) have been described. Post-dissection cadaver handing and soft-tissue disposal protocols have also been described. Overall, the cadaver dissections provide holistic surgical learning for the residents, specialty trainees, and practitioners. This article may act as a basic step-wise guide for starting the cadaver-based oculoplastics lab dissection in various institutes and workshops.

Use of konjac in a novel colonic endoscopic submucosal dissection training model that is inexpensive and hygienic.

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