Systematic Review of the Use of 3-Dimensional Printing in Surgical Teaching and Assessment

Three-dimensional printed anatomical models as an educational tool for orthopaedic surgical trainees - A single institution experience

Objective

To evaluate the utility of three-dimensional (3D) anatomical models as an educational tool among Orthopaedic surgical trainees.

Methods

Seven types of 3D anatomical models - humerus, elbow, ankle, calcaneum, knee, femur, and pelvis- based on patients' computational tomography (CT) scans were printed in the study institution and used by surgical trainees preoperatively. Responses were collected in the form of a Likert scale questionnaire. Descriptive statistics of participants' ratings were calculated. Non-parametric analysis using Wilcoxon test and Kruskal-Wallis test was performed to determine if effectiveness varied with gender, clinical experience, and anatomical model type.

Design

Observational cross-sectional study.

Setting

Single center study.

Participant selection criteria

All participants within a period of 16 months who were Orthopaedic surgical trainees within the study institution and utilised 3D anatomical models preoperatively were selected for this study.

Outcome measures and comparisons

Primary outcome was Likert scale ratings for three aspects - understanding of patients' anatomy, learning of a patient-specific orthopaedic condition, retention of anatomical knowledge.

Results

This study revealed that 3D anatomical models were well-received as an educational tool among Orthopaedic surgical trainees. There were no significant differences between gender, clinical experience or anatomical model type regarding 3D models in improving understanding of patient anatomy and retention of anatomical knowledge (p < 0.05). There were significant differences among participants based on clinical experience regarding the use of 3D models in learning of the patient-specific orthopaedic condition (p = 0.0106).

Conclusions

Preliminary results from this study demonstrate overall effectiveness of 3D models as an educational tool in Orthopaedic surgery, but is limited by the qualitative nature of data collected. Higher quality evidence is required to demonstrate that 3D anatomical models are effective tools to impart critical knowledge of anatomy to surgical trainees.

Level of evidence

IV.

Innovating neurosurgical training: a comprehensive evaluation of a 3D-printed intraventricular neuroendoscopy simulator and systematic review of the literature

Objective

The objective of this study was to develop and evaluate a low-cost 3D-printed simulator to improve the ability of neurosurgical residents to handle and coordinate endoscopes in performing technically demanding procedures such as neuroendoscopic removal of ventricular tumors or endoscopic third ventriculostomy (ETV).

Methods

The simulator was developed, printed in-house, and evaluated in a trial involving neurosurgery residents who performed ETV and intraventricular tumor resection tasks using it. Participants completed a questionnaire that assessed various aspects of the simulator's effectiveness, including anatomical visualization, procedural understanding, competency enhancement, and subjective impressions.

Results

A total of 12 participants were included in the evaluation. The majority (n = 7, 53.85%) were male, with a mean age of 29.8 ± 3.27 years and 4 ± 2 years of neurosurgical experience. All participants agreed or strongly agreed (4.5 ± 0.50) that the 3D printed simulator helped develop systematic intraventricular visualization and understanding of surgical steps (4.42 ± 0.64). The handling of the endoscope was rated as realistic (4.5 ± 0.50), while the haptic qualities of the tumor were rated lower (3.83 ± 0.80; 3.92 ± 0.64). Training increased competence (4.25 ± 0.45) and coordination skills (4.5 ± 0.50), with 75% (n = 9) feeling more confident with neuroendoscopic instruments and 91.7% (n = 11) in future procedures.

Conclusion

The developed 3D-printed simulator offers an accessible and practical training resource for neurosurgical residents, addressing the limitations of traditional training methods. The simulator appears to improve procedural skills and the competence of future neurosurgeons, potentially improving patient safety and outcomes in neurosurgical practice.

Can high-fidelity 3D models be a good alternative for cadaveric materials in skill assessment for endoscopic sinus surgery? A comparison study in assessment for surgical performance in 3D models and cadavers

Introduction

Traditionally formal assessment of surgical skills has not been part of a surgeon's accreditation process. The widely adopted apprentice model of "on-the-job training" does create additional risk for the patients. In the past surgical training has used cadavers, but these are expensive, require dedicated wet-lab facilities and are in increasingly short supply. In many countries religious and cultural practices also preclude cadaveric use. Recent 3D-printed technology allows mass reproduction of high-fidelity 3D models. In this study, we examined the utility of 3D sinus models compared to cadaver dissection for surgical skill assessment for endoscopic sinus surgery (ESS).

Materials and methods

A total of 17 otolaryngologists performed Endoscopic Sinus Surgery (ESS) on 3D printed sinus models and then repeated these procedures on cadavers. Their surgical performance was assessed with the Objective Structured Assessment of Technical Skills (OSATS) score for ESS and time was taken to complete an ESS procedure. Their performance on the 3D models and cadavers was compared.

Results

There were no significant differences in the OSATS score between 3D models and cadavers (50.41 ± 13.31 vs. 48.29 ± 16.01, p = 0.36). There was a strong positive correlation between the score in 3D models and those in cadavers (r = 0.84, p < 0.001). No significant differences were found in time for a mini-ESS (21:29 ± 0:10 vs. 20:33 ± 0:07, p = 0.53). There were positive correlations between 3D models and cadavers in time taken for a mini-ESS (r = 0.55, p = 0.04).

Conclusion

The surgical performance on the 3D models was comparable to that on cadavers. This supports the utility of the 3D models as an inexhaustible alternative for cadavers in ESS surgical skill assessment.

A novel 3D printed model for educating medical students on limb fractures: a randomized controlled preliminary study

BACKGROUND

Medical education related to bone fracture must address numerous challenges including complex anatomical characteristics, diverse injury mechanisms, fracture typing, and treatment modalities. Our newly developed 3D printed model comprises components that may be combined or split to simulate various anatomical features, fracture types, and treatment modalities. This study aims to analyze the teaching utility of the new 3D-printed model compared with the traditional solid model.

METHODS

This prospective study included 112 students randomly assigned to fracture-related education with a conventional model or the newly developed 3D-printed model. All students received 40 min of lecture, 20 min for femoral neck and 20 min for tibiofibular fractures, and a post-class quiz (10 min each) immediately followed. Scores on tests of fracture-related knowledge and user satisfaction were measured pre and post education for comparison.

RESULTS

The 3D printing group had an advantage in retention of anatomic knowledge, fracture typing and choice of treatment for the femoral neck fracture (P < 0.05). For the tibiofibular fracture the 3D printing group had an advantage in retention of anatomic knowledge and fracture complications (P < 0.05).Scores on the questionnaire survey also showed increased satisfaction in the 3D-printed model group(P < 0.05).

CONCLUSIONS

The proposed 3D-printed model can enhance the teaching effect significantly and has potential for widespread use in medical student education.

Explor-A-Thora: A Novel Three-Dimensionally Printed Pleural Simulator

Background

For procedural education, the shift from the traditional apprenticeship model to simulation-based mastery has become increasingly accepted as the gold standard and has underscored the importance of high-fidelity, cost-effective training options. However, cost-effective pleural procedure simulators providing both realistic haptic feedback and ultrasound compatibility are lacking.

Objective

We aimed to create a pleural procedure simulator with characteristics of human tissue, at low cost and with ultrasound compatibility.

Methods

This work used design-based research principles and a collaborative rapid iteration approach in collaboration with the University of California, San Francisco, Makers Lab and design-based researchers at the University of California, Berkeley, which led to the creation of a three-dimensionally printed pleural procedure simulator.

Results

The needs assessment indicated significant discomfort with pleural procedures and a request for more accessible simulation opportunities. Iterative prototyping resulted in a three-dimensionally printed rib cage and a series of innovations in the fluid pocket and skin layers to provide realistic tactile feedback and ultrasound imaging compatibility. The final model costs significantly less than commercial simulators, with durable components and replaceable parts that can be reused multiple times.

Conclusion

The development of a low-cost, high-fidelity pleural procedure simulator addresses the current limitations of commercially available pleural simulators. By integrating three-dimensional printing technology and easily accessible materials, we were able to produce a simulator that closely replicates the feel of human tissue, allows ultrasound use, and is adaptable for different patient anatomies and clinical scenarios. This novel simulator is a scalable solution to elevate the standard of procedural education and ultimately positively affect patient care.

Dimensional Accuracy in 3D Printed Medical Models: A Follow-Up Study on SLA and SLS Technology

Background: With the rise of new 3D printers, assessing accuracy is crucial for obtaining the best results in patient care. Previous studies have shown that the highest accuracy is achieved with SLS printing technology; however, SLA printing technology has made significant improvements in recent years. Methods: In this study, a realistic anatomical model of a mandible and skull, a cutting guide for mandibular osteotomy, and a splint for orthognathic surgery were replicated five times each using two different 3D printing technologies: SLA and SLS. Results: The SLA group had a median trueness RMS value of 0.148 mm and a precision RMS value of 0.117 mm. The SLS group had a median trueness RMS value of 0.144 mm and a precision RMS value of 0.096 mm. There was no statistically significant difference in RMS values between SLS and SLA technologies regarding trueness. Regarding precision, however, the RMS values for SLS technology were significantly lower in the splint and cutting guide applications than those printed with SLA technology. Conclusions: Both 3D printing technologies produce modern models and applications with equally high dimensional accuracy. Considering current cost pressures experienced by hospitals, the lower-cost SLA 3D printer is a reliable choice for point-of-care 3D printing.

3D PRINTING IN COMPLEX TIBIAL FRACTURE CLASSIFICATION & PLANNING

Objective

Tibial plateau fractures are common intra-articular fractures that pose classification and treatment challenges for orthopedic surgeons.

Objective

This study examines the value of 3D printing for classifying and planning surgery for complex tibial plateau fractures.

Methods

We reviewed 54 complex tibial plateau fractures treated at our hospital from January 2017 to January 2019. Patients underwent preoperative spiral CT scans, with DICOM data processed using Mimics software. 3D printing technology created accurate 1:1 scale models of the fractures. These models helped subdivide the fractures into seven types based on the tibial plateau's geometric planes. Surgical approaches and simulated operations, including fracture reduction and plate placement, were planned using these models.

Results

The 3D models accurately depicted the direction and extent of fracture displacement and plateau collapse. They facilitated the preoperative planning, allowing for precise reconstruction strategies and matching intraoperative details with the pre-printed models. Post-surgery, the anatomical structure of the tibial plateau was significantly improved in all 54 cases.

Conclusion

3D printing effectively aids in the classification and preoperative planning of complex tibial plateau fractures, enhancing surgical outcomes and anatomical restoration. Level of Evidence IV, Prospective Study.

Three-Dimensional Printing in Surgical Education: An Updated Systematic Review of the Literature

INTRODUCTION

Three-dimensional printing (3DP) is being integrated into surgical practice at a significant pace, from preprocedural planning to procedure simulation. 3DP is especially useful in surgical education, where printed models are highly accurate and customizable. The aim of this study was to evaluate how 3DP is being integrated most recently into surgical residency training.

METHODS

We performed a structured literature search of the OVID/MEDLINE, EMBASE, and PUBMED databases following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Articles published from 2016 to 2023 that met predefined inclusion and exclusion criteria were included. Data extracted included surgical subspecialty using 3DP, application of 3DP, and any reported satisfaction measures of trainees. A thorough analysis of pooled data was performed to evaluate satisfaction rates among studies.

RESULTS

A total of 85 studies were included. The median number of participants was 18 (interquartile range 10-27). Fourteen surgical disciplines were represented, with ear, nose, and throat/otolaryngology having the highest recorded utilization of 3DP models among residents and medical students (22.0%), followed by neurosurgery (14.0%) and urology (12.0%). 3DP models were created most frequently to model soft tissue (35.3%), bone (24.7%), vessel (14.1%), mixed (16.4%), or whole organs (6.66%) (Fig.1). Feedback from trainees was overwhelmingly positive regarding the fidelity of the models and their support for integration into their training programs. Among trainees, the combined satisfaction rate with their use in the curriculum was 95% (95% confidence interval, 0.92-0.97), and the satisfaction rate with the model fidelity was 90% (95% confidence interval, 0.86-0.94).

CONCLUSIONS

There is wide variation in the surgical specialties utilizing 3DP models in training. These models are effective in increasing trainee comfort with both common and rare scenarios and are associated with a high degree of resident support and satisfaction. Plastic surgery programs may benefit from the integration of this technology, potentially strengthening future surgical curricula. Objective evaluations of their pedagogic effects on residents are areas of future research.

Design and Validation of a 3D Printed Cranio-Facial Simulator: A Novel Tool for Surgical Education

OBJECTIVE

To assess the ability of current 3D printing technology to generate a craniofacial bony and soft tissue anatomical model for use in simulating the performance of a fronto-orbital advancement (FOA) osteotomy and then to further assess the value of the model as an educational tool.

DESIGN

Anatomic models were designed with a process of serial anatomic segmentation/design, 3D printing, dissection, and device refinement. A validation study was conducted with 5 junior and 5 senior plastic surgery residents. The validation study incorporated a multiple-choice Knowledge Assessment test (KA), an Objective Structured Assessment of Technical skills (OSATs), a Global Rating Scale (GRS) and a Michigan Standard Simulation Experience Scale (MiSSES). We compared the scores of both the junior and senior residents and compared junior resident scores, before and after viewing a lecture/demonstration.

RESULTS

MiSSES showed high face validity with a score of 85.1/90, signifying high satisfaction with the simulator learning experience. Simulation and the lecture/demonstration improved the junior resident average KA score from 5.6/10 to 9.6/10 (P = .02), OSATs score from 32.4/66 to 64.4/66 (P < .001) and GRS score from 13.9/35 to 27.5/35 (P < .001). The senior residents OSATs score of 56.3/66 was higher than the pre-lecture juniors (32.4/66) (P < .001), but lower than the post-lecture juniors (64.4/66) (P < .001).

CONCLUSION

We have successfully fabricated a 3D printed craniofacial simulator capable of being used as an educational tool alongside traditional surgical training. Next steps would be improving soft tissue realism, inclusion of patient and disease specific anatomy and creation of models for other surgical specialties.

3D-printed model for gingival flap surgery simulation: Development and pilot test

INTRODUCTION

To assess the feasibility of a realistic model for learning oral flaps using 3D printing technology.

MATERIALS AND METHODS

A mould was designed to reproduce the mandibular gingival mucosa, and a mandibular model was created using a three-dimensional printer for training undergraduate students to perform gingival flaps. After a short interview about its use, the participants were asked to use the simulator and provide feedback using a 5-point Likert questionnaire.

RESULTS

The 3D-printed oral surgery flap training model was practical and inexpensive. The model was very realistic, educational and useful for hands-on training.

CONCLUSIONS

3D printing technology offers new possibilities for training in dental treatments that are currently difficult to replicate. The use of this simulator for oral flap surgery was well-received and considered promising by the participants.

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.

Training and assessment for colorectal surgery and appendicectomy- a systematic review

AIM

There is currently an increased focus on competency-based training, in which training and assessment play a crucial role. The aim of this systematic review is to create an overview of hands-on training methods and assessment tools for appendicectomy and colon and rectal surgery procedures using either an open, laparoscopic or robot-assisted approach.

METHOD

A systematic review of Medline, Embase, Cochrane and Scopus databases was conducted following the PRISMA guidelines. We conducted the last search on 9 March 2023. All published papers describing hands-on training, evaluation of performance data and development of assessment tools were eligible. The quality of studies and the validity evidence of assessment tools are reported.

RESULTS

Fifty-one studies were identified. Laparoscopic assessment tools are abundant, but the literature still lacks good-quality assessment tools for open appendicectomy, robotic colectomy and open rectal surgery. Overall, there is a lack of discussion regarding the establishment of pass/fail standards and the consequences of assessment. Virtual reality simulation is used more for appendicectomy than colorectal procedures. Only a few of the studies investigating training were of acceptable quality. There is a need for high-quality studies in open and robotic-assisted colon surgery and all approaches to rectal surgery.

CONCLUSION

This review provides an overview of current training methods and assessment tools and identifies where more research is needed based on the quality of the studies and the current validity evidence.

Quality assurance of 3D-printed patient specific anatomical models: a systematic review

BACKGROUND

The responsible use of 3D-printing in medicine includes a context-based quality assurance. Considerable literature has been published in this field, yet the quality of assessment varies widely. The limited discriminatory power of some assessment methods challenges the comparison of results. The total error for patient specific anatomical models comprises relevant partial errors of the production process: segmentation error (SegE), digital editing error (DEE), printing error (PrE). The present review provides an overview to improve the general understanding of the process specific errors, quantitative analysis, and standardized terminology.

METHODS

This review focuses on literature on quality assurance of patient-specific anatomical models in terms of geometric accuracy published before December 4th, 2022 (n = 139). In an attempt to organize the literature, the publications are assigned to comparable categories and the absolute values of the maximum mean deviation (AMMD) per publication are determined therein.

RESULTS

The three major examined types of original structures are teeth or jaw (n = 52), skull bones without jaw (n = 17) and heart with coronary arteries (n = 16). VPP (vat photopolymerization) is the most frequently employed basic 3D-printing technology (n = 112 experiments). The median values of AMMD (AMMD: The metric AMMD is defined as the largest linear deviation, based on an average value from at least two individual measurements.) are 0.8 mm for the SegE, 0.26 mm for the PrE and 0.825 mm for the total error. No average values are found for the DEE.

CONCLUSION

The total error is not significantly higher than the partial errors which may compensate each other. Consequently SegE, DEE and PrE should be analyzed individually to describe the result quality as their sum according to rules of error propagation. Current methods for quality assurance of the segmentation are often either realistic and accurate or resource efficient. Future research should focus on implementing models for cost effective evaluations with high accuracy and realism. Our system of categorization may be enhancing the understanding of the overall process and a valuable contribution to the structural design and reporting of future experiments. It can be used to educate specialists for risk assessment and process validation within the additive manufacturing industry.

Point-of-Care Orthopedic Oncology Device Development

BACKGROUND

The triad of 3D design, 3D printing, and xReality technologies is explored and exploited to collaboratively realize patient-specific products in a timely manner with an emphasis on designs with meta-(bio)materials.

METHODS

A case study on pelvic reconstruction after oncological resection (osteosarcoma) was selected and conducted to evaluate the applicability and performance of an inter-epistemic workflow and the feasibility and potential of 3D technologies for modeling, optimizing, and materializing individualized orthopedic devices at the point of care (PoC).

RESULTS

Image-based diagnosis and treatment at the PoC can be readily deployed to develop orthopedic devices for pre-operative planning, training, intra-operative navigation, and bone substitution.

CONCLUSIONS

Inter-epistemic symbiosis between orthopedic surgeons and (bio)mechanical engineers at the PoC, fostered by appropriate quality management systems and end-to-end workflows under suitable scientifically amalgamated synergies, could maximize the potential benefits. However, increased awareness is recommended to explore and exploit the full potential of 3D technologies at the PoC to deliver medical devices with greater customization, innovation in design, cost-effectiveness, and high quality.

A novel simulation module for segmental mandibulectomy and mandible reconstruction using 3D models

INTRODUCTION

Mandibular resection and reconstruction are common but complex procedures in head and neck surgery. Resection with adequate margins is critical to the success of the procedure but technical training is restricted to real case experience. Here we describe our experience in the development and evaluation of a mandibular resection and reconstruction simulation module.

METHODS

3D printed (3DP) models of a mandible with a pathologic lesion were developed from imaging data from a patient with an ameloblastoma. During an educational conference, otolaryngology trainees participated in a simulation in which they reviewed a CT scan of the pathologic mandible and then planned their osteotomies before and after handling a 3DP model demonstrating the lesion. The adequacy of the osteotomy margins was assessed and components of the simulation were rated by participants with pre- and post-training surveys.

RESULTS

52 participants met criteria. After reviewing the CT scan, 34 participants (65.3 %) proposed osteotomies clear of the lesion. This proportion improved to 48 (92.3 %, p = 0.001) after handling the 3D model. Among those with initially adequate margins (n = 33), 45.5 % decreased their margins closer to the ideal, 27.2 % made no revision, 21.2 % widened their margins. 92 % of participants found the simulation beneficial for surgical planning and technical training. After the exercise, the majority of participants had increased confidence in conceptualizing the boundaries of the lesion (69.2 %) and their abilities to ablate (76.5 %).

CONCLUSIONS

The structured mandibulectomy simulation using 3DP models was useful in the development of trainee experience in segmental mandible resection.

LAY SUMMARY

This study presents the first mandibulectomy simulation module for trainees with the use of 3DP models. The use of a 3DP model was also shown to improve the quality of surgical training.

Use of individualized 3D-printed models of pancreatic cancer to improve surgeons' anatomic understanding and surgical planning

OBJECTIVES

Three-dimensional (3D) printing has been increasingly used to create accurate patient-specific 3D-printed models from medical imaging data. We aimed to evaluate the utility of 3D-printed models in the localization and understanding of pancreatic cancer for surgeons before pancreatic surgery.

METHODS

Between March and September 2021, we prospectively enrolled 10 patients with suspected pancreatic cancer who were scheduled for surgery. We created an individualized 3D-printed model from preoperative CT images. Six surgeons (three staff and three residents) evaluated the CT images before and after the presentation of the 3D-printed model using a 7-item questionnaire (understanding of anatomy and pancreatic cancer [Q1-4], preoperative planning [Q5], and education for trainees or patients [Q6-7]) on a 5-point scale. Survey scores on Q1-5 before and after the presentation of the 3D-printed model were compared. Q6-7 assessed the 3D-printed model's effects on education compared to CT. Subgroup analysis was performed between staff and residents.

RESULTS

After the 3D-printed model presentation, survey scores improved in all five questions (before 3.90 vs. after 4.56, p < 0.001), with a mean improvement of 0.57‒0.93. Staff and resident scores improved after a 3D-printed model presentation (p < 0.05), except for Q4 in the resident group. The mean difference was higher among the staff than among the residents (staff: 0.50‒0.97 vs. residents: 0.27‒0.90). The scores of the 3D-printed model for education were high (trainees: 4.47 vs. patients: 4.60) compared to CT.

CONCLUSION

The 3D-printed model of pancreatic cancer improved surgeons' understanding of individual patients' pancreatic cancer and surgical planning.

CLINICAL RELEVANCE STATEMENT

The 3D-printed model of pancreatic cancer can be created using a preoperative CT image, which not only assists surgeons in surgical planning but also serves as a valuable educational resource for patients and students.

KEY POINTS

• A personalized 3D-printed pancreatic cancer model provides more intuitive information than CT, allowing surgeons to better visualize the tumor's location and relationship to neighboring organs. • In particular, the survey score was higher among staff who performed the surgery than among residents. • Individual patient pancreatic cancer models have the potential to be used for personalized patient education as well as resident education.

Training models and simulators for endoscopic transsphenoidal surgery: a systematic review

Endoscopic transsphenoidal surgery is a novel surgical technique requiring specific training. Different models and simulators have been recently suggested for it, but no systematic review is available. To provide a systematic and critical literature review and up-to-date description of the training models or simulators dedicated to endoscopic transsphenoidal surgery. A search was performed on PubMed and Scopus databases for articles published until February 2023; Google was also searched to document commercially available. For each model, the following features were recorded: training performed, tumor/arachnoid reproduction, assessment and validation, and cost. Of the 1199 retrieved articles, 101 were included in the final analysis. The described models can be subdivided into 5 major categories: (1) enhanced cadaveric heads; (2) animal models; (3) training artificial solutions, with increasing complexity (from "box-trainers" to multi-material, ct-based models); (4) training simulators, based on virtual or augmented reality; (5) Pre-operative planning models and simulators. Each available training model has specific advantages and limitations. Costs are high for cadaver-based solutions and vary significantly for the other solutions. Cheaper solutions seem useful only for the first stages of training. Most models do not provide a simulation of the sellar tumor, and a realistic simulation of the suprasellar arachnoid. Most artificial models do not provide a realistic and cost-efficient simulation of the most delicate and relatively common phase of surgery, i.e., tumor removal with arachnoid preservation; current research should optimize this to train future neurosurgical generations efficiently and safely.

Use of 3D-printing cerebral aneurysm model assisting microcatheter shaping in neurovascular intervention technique training

BACKGROUND

Microcatheter shaping plays a vital role in coil embolization of cerebral aneurysms, while the complicated method and insufficient training opportunities make it difficult for junior neurovascular clinicians to master this technique. In this program, we constructed a novel training method and assessment system for microcatheter shaping in coil embolization of cerebral aneurysms with 3D technique, and evaluated its efficacy for microcatheter shaping training in junior neurovascular clinicians.

METHODS

Patient-specific models for cerebral aneurysms in different locations and with different morphologies were selected by experienced senior neurovascular clinicians. The solid polylactic acid model and the soft hollow crystal silicone model of intracranial aneurysms were then made separately for shaping reference and assessment in the training course. Twelve residents without prior experience of microcatheter shaping and 25 neurovascular clinicians who have in vivo experience of microcatheter shaping on 3-5 occasions were selected for this training program and randomly divided into the traditional training group and the experimental training group. Four senior neurovascular clinicians assisted and guided the trainees in two groups and evaluated the time and accuracy of microcatheter shaping.

RESULTS

Eighteen trainees were assigned to the traditional training group, among which 4 had prior experience in microcatheter shaping. The other 19 were assigned to the experimental training group, including 8 with prior experience. No statistical difference in the distribution of experienced students between the two groups was noted(P = 0.295). After the training session, the shaping time was found shorter in the experimental training group than that in the traditional training group (40.3.5 ± 16.2 s vs. 54.2 ± 16.4 s, P = 0.014), while the shaping score was found higher in the experimental training group than that in the traditional training group (4.4 ± 0.5 vs. 2.6 ± 1.2, P < 0.001). Specifically, for the trainees without prior experience, the experimental training group also showed less time consumption and higher score (Time: 52.7 ± 7.7 vs. 61.5 ± 9.5, P = 0.02; Score 4.1 ± 0.5 vs. 2.3 ± 1.1, P < 0.01). Meanwhile, for the trainees with prior experience, the advantage was noted in shaping score (4.7 ± 0.3 vs. 3.9 ± 0.6, P < 0.01) but not in time consumption (23.3 ± 4.4 vs. 28.5 ± 3.9, P = 0.07).

CONCLUSION

This training program is quite effective at teaching junior neurovascular physicians the essential surgical abilities required for coiling cerebral aneurysms.

Full-sized realistic 3D printed models of liver and tumour anatomy: a useful tool for the clinical medicine education of beginning trainees

BACKGROUND

Simulation-based medical education (SBME) and three-dimensional printed (3DP) models are increasingly used in continuing medical education and clinical training. However, our understanding of their role and value in improving trainees' understanding of the anatomical and surgical procedures associated with liver surgery remains limited. Furthermore, gender bias is also a potential factor in the evaluation of medical education. Therefore, the aim of this study was to evaluate the educational benefits trainees receive from the use of novel 3DP liver models while considering trainees' experience and gender.

METHODS

Full-sized 3DP liver models were developed and printed using transparent material based on anonymous CT scans. We used printed 3D models and conventional 2D CT scans of the liver to investigate thirty trainees with various levels of experience and different genders in the context of both small group teaching and formative assessment. We adopted a mixed methods approach involving both questionnaires and focus groups to collect the views of different trainees and monitors to assess trainees' educational benefits and perceptions after progressing through different training programs. We used Objective Structured Clinical Examination (OSCE) and Likert scales to support thematic analysis of the responses to the questionnaires by trainees and monitors, respectively. Descriptive analyses were conducted using SPSS statistical software version 21.0.

RESULTS

Overall, a 3DP model of the liver is of great significance for improving trainees' understanding of surgical procedures and cooperation during operation. After viewing the personalized full-sized 3DP liver model, all trainees at the various levels exhibited significant improvements in their understanding of the key points of surgery (p < 0.05), especially regarding the planned surgical procedure and key details of the surgical procedures. More importantly, the trainees exhibited higher levels of satisfaction and self-confidence during the operation regardless of gender. However, with regard to gender, the results showed that the improvement of male trainees after training with the 3DP liver model was more significant than that of female trainees in understanding and cooperation during the surgical procedure, while no such trend was found with regard to their understanding of the base knowledge.

CONCLUSION

Trainees and monitors agreed that the use of 3DP liver models was acceptable. The improvement of the learning effect for practical skills and theoretical understanding after training with the 3DP liver models was significant. This study also indicated that training with personalized 3DP liver models can improve all trainees' presurgical understanding of liver tumours and surgery and males show more advantage in understanding and cooperation during the surgical procedure as compared to females. Full-sized realistic 3DP models of the liver are an effective auxiliary teaching tool for SBME teaching in Chinese continuing medical education.

3-D Printed Fracture Models Improve Resident Performance and Clinical Outcomes in Operative Fracture Management

OBJECTIVE

To determine if preoperative examination of patient additive manufactured (AM) fracture models can be used to improve resident operative competency and patient outcomes.

DESIGN

Prospective cohort study. Seventeen matched pairs of fracture fixation surgeries (for a total of 34 surgeries) were performed. Residents first performed a set of baseline surgeries (n = 17) without AM fracture models. The residents then performed a second set of surgeries randomly assigned to include an AM model (n = 11) or to omit it (n = 6). Following each surgery, the attending surgeon evaluated the resident using an Ottawa Surgical Competency Operating Room Evaluation (O-Score). The authors also recorded clinical outcomes including operative time, blood loss, fluoroscopy duration, and patient reported outcome measurement information system (PROMIS) scores of pain and function at 6 months.

SETTING

Single-center academic level one trauma center.

PARTICIPANTS

Twelve orthopaedic residents, between postgraduate year (PGY) 2 and 5, participated in this study.

RESULTS

Residents significantly improved their O-Scores between the first and second surgery when they trained with AM models for the second surgery (p = 0.004, 2.43 ± 0.79 versus 3.73 ± 0.64). Similar improvements were not observed in the control group (p = 0.916, 2.69 ± 0.69 versus 2.77 ± 0.36). AM model training also significantly improved clinical outcomes, including surgery time (p = 0.006), fluoroscopy exposure time (p = 0.002), and patient reported functional outcomes (p = 0.0006).

CONCLUSIONS

Conclusions: Training with AM fracture models improves the performance of orthopaedic surgery residents during fracture surgery.

Three-Dimensional printed model for preclinical training in oral radiology

INTRODUCTION

3D printing is experiencing significant growth in the teaching and learning process. This study aims to present a 3D printed skull model for preclinical intraoral radiographic practice.

MATERIALS AND METHODS

Two 3D printed mannequins were created. One mannequin used an STL file of a skull that was edited using two 3D modelling software (Meshmixer and Netfabb). The second mannequin was designed directly from a patient's segmented CBCT data and then converted into an STL file. Both mannequins were printed using fused deposition modelling (FDM) technology and polylactic acid (PLA) filament; teeth for the second mannequin were also printed using digital light processing (DLP). The printed skull bones were attached, the mandible was articulated to the articular fossa of the temporal bone, and the teeth were inserted into the alveoli. Intraoral radiographs of both mannequins were taken using a digital sensor (RVG 5100, Carestream).

RESULTS

Both 3D printed mannequins showed satisfactory radiographic appearance, allowing geometric representation of each intraoral radiographic projection, regardless of STL file origin. Anatomical structures, such as the periodontal ligament space, zygomatic process of the maxilla and intermaxillary suture, were represented. The material cost of the first and second printed prototype was $34.00 and $39.00, respectively.

CONCLUSIONS

The use of 3D printed models is presented as an alternative to artificial commercial phantoms for the preclinical training of intraoral radiographic techniques through the combined benefits of superior radiographic projection quality, the possibility of model manipulation and an affordable price.

3D printing exposure and perception in radiology residency: survey results of radiology chief residents

RATIONALE AND OBJECTIVES

The purpose of this study is to summarize a survey of radiology chief residents focused on 3D printing in radiology.

MATERIALS AND METHODS

An online survey was distributed to chief residents in North American radiology residencies by subgroups of the Association of University Radiologists. The survey included a subset of questions focused on the clinical use of 3D printing and perceptions of the role of 3D printing and radiology. Respondents were asked to define the role of 3D printing at their institution and asked about the potential role of clinical 3D printing in radiology and radiology residencies.

RESULTS

152 individual responses from 90 programs were provided, with a 46% overall program response rate (n = 90/194 radiology residencies). Most programs had 3D printing at their institution (60%; n = 54/90 programs). Among the institutions that perform 3D printing, 33% (n = 18/54) have structured opportunities for resident contribution. Most residents (60%; n = 91/152 respondents) feel they would benefit from 3D printing exposure or educational material. 56% of residents (n = 84/151) believed clinical 3D printing should be centered in radiology departments. 22% of residents (n = 34/151) believed it would increase communication and improve relationships between radiology and surgery colleagues. A minority (5%; 7/151) believe 3D printing is too costly, time-consuming, or outside a radiologist's scope of practice.

CONCLUSIONS

A majority of surveyed chief residents in accredited radiology residencies believe they would benefit from exposure to 3D printing in residency. 3D printing education and integration would be a valuable addition to current radiology residency program curricula.

A systematic review of the application of 3D-printed models to colorectal surgical training

BACKGROUND

The aim of this review was to explore the role of three-dimensional (3D) printing in colorectal surgical education and procedural simulation, and to assess the effectiveness of 3D-printed models in anatomic and operative education in colorectal surgery.

METHODS

A systematic review of the literature was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify relevant publications relating to the use of 3D-printed models in colorectal surgery in an educational context. The search encompassed OVID Medline, Web of Science and EMBASE including papers in English published from 1 January 1995 to 1 January 2023. A total of 1018 publications were screened, and 5 met the criteria for inclusion in this review.

RESULTS

Four distinct 3D models were described across five studies. Two models demonstrated objective benefits in the use of 3D-printed models in anatomical education in academic outcomes at all levels of learner medical experience and were well accepted by learners. One model utilised for preoperative visualisation demonstrated improved operative outcomes in complete mesocolic excision compared with preoperative imaging review, with a 22.1% reduction in operative time (p < 0.001), 9.2% reduction in surgical duration (p = 0.035) and 37.3% reduction in intraoperative bleeding volume amongst novice surgeons (p < 0.01). Technical simulation has been demonstrated in a feasibility context in one model but remains limited in scope and application on account of the characteristics of available printing materials.

CONCLUSIONS

3D printing is well accepted and effective for anatomic education and preoperative procedural planning amongst colorectal surgeons, trainees and medical students but remains a technology in the early stages of its possible application. Technological advancements are required to improve the tissue realism of 3D-printed organ models to achieve greater fidelity and provide realistic colorectal surgical simulations.

Application of 3D Printing Technology in the Treatment of Hoffa's Fracture Nonunion

Objective  To evaluate a proposed three-dimensional (3D) printing process of a biomodel developed with the aid of fused deposition modeling (FDM) technology based on computed tomography (CT) scans of an individual with nonunion of a coronal femoral condyle fracture (Hoffa's fracture). Materials and Methods  Thus, we used CT scans, which enable the evaluation of the 3D volumetric reconstruction of the anatomical model, as well as of the architecture and bone geometry of sites with complex anatomy, such as the joints. In addition, it enables the development of the virtual surgical planning (VSP) in a computer-aided design (CAD) software. This technology makes it possible to print full-scale anatomical models that can be used in surgical simulations for training and in the choice of the best placement of the implant according to the VSP. In the radiographic evaluation of the osteosynthesis of the Hoffa's fracture nonunion, we assessed the position of the implant in the 3D-printed anatomical model and in the patient's knee. Results  The 3D-printed anatomical model showed geometric and morphological characteristics similar to those of the actual bone. The position of the implants in relation to the nonunion line and anatomical landmarks showed great accuracy in the comparison of the patient's knee with the 3D-printed anatomical model. Conclusion  The use of the virtual anatomical model and the 3D-printed anatomical model with the additive manufacturing (AM) technology proved to be effective and useful in planning and performing the surgical treatment of Hoffa's fracture nonunion. Thus, it showed great accuracy in the reproducibility of the virtual surgical planning and the 3D-printed anatomical model.

Effectiveness in Sterilization of Objects Produced by 3D Printing with Polylactic Acid Material: Comparison Between Autoclave and Ethylene Oxide Methods

Objective  Due to the popularity of 3D technology, surgeons can create specific surgical guides and sterilize them in their institutions. The aim of the present study is to compare the efficacy of the autoclave and ethylene oxide (EO) sterilization methods for objects produced by 3D printing with polylactic acid (PLA) material. Methods Forty cubic-shaped objects were printed with PLA material. Twenty were solid and 20 were hollow (printed with little internal filling). Twenty objects (10 solid and 10 hollow) were sterilized in autoclave, forming Group 1. The others (10 solid and 10 hollow) were sterilized in EO, composing Group 2. After sterilization, they were stored and referred to culture. Hollow objects of both groups were broken during sowing, communicating the dead space with the culture medium. The results obtained were statistically analyzed (Fisher exact test and residue analysis). Results  In group 1 (autoclave), there was bacterial growth in 50% of solid objects and in 30% of hollow objects. In group 2 (EO), growth occurred in 20% of hollow objects, with no bacterial growth in solid objects (100% of negative samples). The bacteria isolated in the positive cases was non-coagulase-producing Staphylococcus Gram positive. Conclusions  Sterilization by both autoclave and EO was not effective for hollow printed objects. Solid objects sterilized by autoclave did not demonstrate 100% of negative samples and were not safe in the present assay. Complete absence of contamination occurred only with solid objects sterilized by EO, which is the combination recommended by the authors.

Mental workload during endoscopic sinus surgery is associated with surgeons' skill levels

Introduction

Surgeons' mental workload during endoscopic sinus surgery (ESS) has not been fully evaluated. The assessment was challenging due to the great diversity of each patient's anatomy and the consequence variety of surgical difficulties. In this study, we examined the mental workload of surgeons with various surgical skill levels during ESS under the standardized condition provided by novel-designed 3D sinus models.

Materials and methods

Forty-seven participants performed a high-fidelity ESS simulation with 3D-printed sinus models. Surgeons' mental workload was assessed with the national aeronautics and space administration-task load index (NASA-TLX). Associations between the total and subscales score of NASA-TLX and surgical skill index, including the board certification status, the number of experienced ESS cases, and the objective structured assessment of technical skills (OSATS), were analyzed. In addition, 10 registrars repeated the simulation surgery, and their NASA-TLX score was compared before and after the repetitive training.

Results

The total NASA-TLX score was significantly associated with OSATS score (p = 0.0001). Primary component analysis classified the surgeons' mental burden into three different categories: (1) the skill-level-dependent factors (temporal demand, effort, and performance), (2) the skill-level-independent factors (mental and physical demand), and (3) frustration. After the repetitive training, the skill-level-dependent factors were alleviated (temporal demand; z = -2.3664, p = 0.0091, effort; z = -2.1704, p = 0.0346, and performance; z = -2.5992, p = 0.0017), the independent factors were increased (mental demand; z = -2.5992, p = 0.0023 and physical demand; z = -2.2509, p = 0.0213), and frustration did not change (p = 0.3625).

Conclusion

Some of the mental workload during ESS is associated with surgical skill level and alleviated with repetitive training. However, other aspects remain a burden or could worsen even when surgeons have gained surgical experience. Routine assessment of registrars' mental burdens would be necessary during surgical training to sustain their mental health.

An Overview of 3D Anatomical Model Printing in Orthopedic Trauma Surgery

Introduction

3D object printing technology is a resource increasingly used in medicine in recent years, mainly incorporated in surgical areas like orthopedics. The models made by 3D printing technology provide surgeons with an accurate analysis of complex anatomical structures, allowing the planning, training, and surgery simulation. In orthopedic surgery, this technique is especially applied in oncological surgeries, bone, and joint reconstructions, and orthopedic trauma surgeries. In these cases, it is possible to prototype anatomical models for surgical planning, simulating, and training, besides printing of instruments and implants.

Purpose

The purpose of this paper is to describe the acquisition and processing from computed tomography images for 3D printing, to describe modeling and the 3D printing process of the biomodels in real size. This paper highlights 3D printing with the applicability of the 3D biomodels in orthopedic surgeries and shows some examples of surgical planning in orthopedic trauma surgery.

Patients and Methods

Four examples were selected to demonstrate the workflow and rationale throughout the process of planning and printing 3D models to be used in a variety of situations in orthopedic trauma surgeries. In all cases, the use of 3D modeling has impacted and improved the final treatment strategy.

Conclusion

The use of the virtual anatomical model and the 3D printed anatomical model with the additive manufacturing technology proved to be effective and useful in planning and performing the surgical treatment of complex articular fractures, allowing surgical planning both virtual and with the 3D printed anatomical model, besides being useful during the surgical time as a navigation instrument.

Application of 3D modeling in a personalized approach to bone osteosynthesis (A literature review)

Three-dimensional printing opens up many opportunities for use in traumatology and orthopedics, because it takes into account personal characteristics of the patients. Modern methods of high-resolution medical imaging can process data to create threedimensional images for printing physical objects. Today, three-dimensional printers are able to create a model of any complexity of shape and geometry. The article provides a review of the literature about three-dimensional digital modeling in shaping implants for osteosynthesis. Data search was carried out on the Scopus, Web of Scince, Pubmed, RSCI databases for the period 2012–2022. The effectiveness of three-dimensional printing for preoperative modeling of bone plates has been confirmed: implants perfectly corresponds with the unique anatomy of the patient, since the template for it is based on the materials of computed tomography. Individual templates can be useful when the geometry of patients' bones goes beyond the standard, and when improved results of surgery are expected due to better matching of implants to the anatomical needs of patients. 

Establishing a Point-of-Care Virtual Planning and 3D Printing Program

Virtual surgical planning (VSP) and three-dimensional (3D) printing have become a standard of care at our institution, transforming the surgical care of complex patients. Patient-specific, anatomic models and surgical guides are clinically used to improve multidisciplinary communication, presurgical planning, intraoperative guidance, and the patient informed consent. Recent innovations have allowed both VSP and 3D printing to become more accessible to various sized hospital systems. Insourcing such work has several advantages including quicker turnaround times and increased innovation through collaborative multidisciplinary teams. Centralizing 3D printing programs at the point-of-care provides a greater cost-efficient investment for institutions. The following article will detail capital equipment needs, institutional structure, operational personnel, and other considerations necessary in the establishment of a POC manufacturing program.

Three-Dimensional Printing in Neurosurgery: A Review of Current Indications and Applications and a Basic Methodology for Creating a Three-Dimensional Printed Model for the Neurosurgical Practice

Introduction Three-dimensional (3D) printing is an affordable aid that is useful in neurosurgery. It allows for better visualization and tactile appreciation of the individual anatomy and regions of interest and therefore potentially lowers the risk of complications. There are various applications of this technology in the field of neurosurgery. Materials and methods In this paper, we present a basic methodology for the creation of a 3D printed model using only open-source software for medical image editing, model generation, pre-printing preparation, and analysis of the literature concerning the practical use of this methodology. Results The literature review on the current applications of 3D printed models in neurosurgery shows that they are mostly used for preoperative planning, surgical training, and simulation, closely followed by their use in patient-specific implants and instrumentation and medical education. Materialise^TM Mimics is the most frequently used commercial software for a 3D modeling for preoperative planning and surgical simulation, while the most popular open-source software for the same applications is 3D Slicer. In this paper, we present the algorithm that we employ for 3D printing using Horos^TM, Blender, and Cura software packages which are all free and open-source. Conclusion Three-dimensional printing is becoming widely available and of significance to neurosurgical practice. Currently, there are various applications of this technology that are less demanding in terms of technical knowledge and required fluency in medical imaging software. These predispositions open the field for further research on the possible use of 3D printing in neurosurgery.

Effectiveness of 3D-printed models prepared from radiological data for anatomy education: A meta-analysis and trial sequential analysis of 22 randomized, controlled, crossover trials

BACKGROUND

Many academicians suggested the supplementary use of 3D-printed models reconstructed from radiological images for optimal anatomy education. 3D-printed model is newer technology available to us. The purpose of this systematic review was to capture the usefulness or effectiveness of this newer technology in anatomy education.

MATERIALS AND METHODS

Twenty-two studies met the inclusion and exclusion criteria for quantitative synthesis. The included studies were sub-grouped according to the interventions and participants. No restrictions were applied based on geographical location, language and publication years. Randomized, controlled trial, cross-sectional and cross-over designs were included. The effect size of each intervention in both participants was computed as a standardized mean difference (SMD).

RESULTS

Twenty-two randomized, controlled trials were included for quantitative estimation of effect size of knowledge acquisition as standardized mean difference in 1435 participants. The pooled effect size for 3D-printed model was 0.77 (0.45-1.09, 95% CI, P < 0.0001) with 86% heterogeneity. The accuracy score was measured in only three studies and estimated effect size was 2.81 (1.08-4.54, 95% CI, P = 0.001) with 92% heterogeneity. The satisfaction score was examined by questionnaire in 6 studies. The estimated effect size was 2.00 (0.69-3.32, 95% CI, P = 0.003) with significant heterogeneity.

CONCLUSION

The participants exposed to the 3D-printed model performed better than participants who used traditional methodologies. Thus, the 3D-printed model is a potential tool for anatomy education.

Implementation of an In-House 3D Manufacturing Unit in a Public Hospital’s Radiology Department

Objective: Three-dimensional printing has become a leading manufacturing technique in healthcare in recent years. Doubts in published studies regarding the methodological rigor and cost-effectiveness and stricter regulations have stopped the transfer of this technology in many healthcare organizations. The aim of this study was the evaluation and implementation of a 3D printing technology service in a radiology department. Methods: This work describes a methodology to implement a 3D printing service in a radiology department of a Spanish public hospital, considering leadership, training, workflow, clinical integration, quality processes and usability. Results: The results correspond to a 6-year period, during which we performed up to 352 cases, requested by 85 different clinicians. The training, quality control and processes required for the scaled implementation of an in-house 3D printing service are also reported. Conclusions: Despite the maturity of the technology and its impact on the clinic, it is necessary to establish new workflows to correctly implement them into the strategy of the health organization, adjusting it to the needs of clinicians and to their specific resources. Significance: This work allows hospitals to bridge the gap between research and 3D printing, setting up its transfer to clinical practice and using implementation methodology for decision support.

Case report: Application of three-dimensional technologies for surgical treatment of portosystemic shunt with segmental caudal vena cava aplasia in two dogs

This case report describes the application of three-dimensional (3D) technologies for the surgical treatment of portosystemic shunt (PSS) with segmental caudal vena cava (CVC) aplasia. Two client-owned dogs were diagnosed with PSS along with segmental CVC aplasia using computed tomography. Through 3D volume and surface rendering, the vascular anatomic anomaly of each patient was identified in detail. A patient-specific 3D vascular model was used for preoperative planning. According to the plan established based on the 3D rendered image and printed model, shunt occlusion was performed using cellophane banding in the first case. An ameroid constrictor was used in the second case. Both patients showed good recovery without any clinical symptoms or complications. The use of 3D technologies in small animals has many advantages, and its use in vascular surgery, as in these cases, is also a therapeutic option worth considering.

Evolving anatomy education strategies for surgical residents: A scoping review

INTRODUCTION

Dedicated anatomy educational time in medical schools has decreased significantly, disproportionately affecting surgical residents. In this scoping review, we aim to consolidate existing evidence, describe ongoing research, and highlight future directions for surgical anatomy education.

METHODS

Two independent investigators searched MEDLINE, EMBASE, and the Cochrane library, for educational interventions targeting anatomy knowledge in surgical residents. English articles until October 28, 2021, were reviewed.

RESULTS

1135 abstracts were considered, and 59 (5.2%) included. Agreement on inclusion was excellent (k = 0.90). The majority were single-cohort studies (53%) and prospective cohort studies (17%). The most common disciplines were General Surgery (17%) and Obstetrics and Gynecology (17%).

DISCUSSION

Cadavers consistently produce positive knowledge gains and are heavily favored by residents. They remain the educational method to which new educational models are compared. New technologies do not yet match cadaver fidelity. Research showing knowledge translation from cadaver labs to patient outcomes remains limited.

Repetitive simulation training with novel 3D-printed sinus models for functional endoscopic sinus surgeries

Background

The purpose of this study was to find a utility of a newly developed 3D-printed sinus model and to evaluate the educational benefit of simulation training with the models for functional endoscopic sinus surgery (FESS).

Material and methods

Forty-seven otolaryngologists were categorized as experts (board-certified physicians with ≥200 experiences of FESS, n = 9), intermediates (board-certified physicians with <200 experiences of FESS, n = 19), and novices (registrars, n = 19). They performed FESS simulation training on 3D-printed models manufactured from DICOM images of computed tomography (CT) scan of real patients. Their surgical performance was assessed with the objective structured assessment of technical skills (OSATS) score and dissection quality evaluated radiologically with a postdissection CT scan. First we evaluated the face, content, and constructive values. Second we evaluated the educational benefit of the training. Ten novices underwent training (training group) and their outcomes were compared to the remaining novices without training (control group). The training group performed cadaveric FESS surgeries before and after the repetitive training.

Results

The feedback from experts revealed high face and content value of the 3D-printed models. Experts, intermediates, and novices demonstrated statistical differences in their OSATS scores (74.7 ± 3.6, 58.3 ± 10.1, and 43.1 ± 11.1, respectively, p < .001), and dissection quality (81.1 ± 13.1, 93.7 ± 15.1, and 126.4 ± 25.2, respectively, p < .001). The training group improved their OSATS score (41.1 ± 8.0 to 61.1 ± 6.9, p < .001) and dissection quality (122.1 ± 22.2 to 90.9 ± 10.3, p = .013), while the control group not. After training, 80% of novices with no prior FESS experiences completed surgeries on cadaver sinuses.

Conclusion

Repeated training using the models revealed an initial learning curve in novices, which was confirmed in cadaveric mock FESS surgeries.

Level of evidence

N/A.

Are 3D-printed Models of Tibial Plateau Fractures a Useful Addition to Understanding Fractures for Junior Surgeons?

BACKGROUND

Tibial plateau fractures are often complex, and they can be challenging to treat. Classifying fractures is often part of the treatment process, but intra- and interobserver reliability of fracture classification systems often is inadequate to the task, and classifications that lack reliability can mislead providers and result in harm to patients. Three-dimensionally (3D)-printed models might help in this regard, but whether that is the case for the classification of tibial plateau fractures, and whether the utility of such models might vary by the experience of the individual classifying the fractures, is unknown.

QUESTIONS/PURPOSES

(1) Does the overall interobserver agreement improve when fractures are classified with 3D-printed models compared with conventional radiology? (2) Does interobserver agreement vary among attending and consultant trauma surgeons, senior surgical residents, and junior surgical residents? (3) Do surgeons' and surgical residents' confidence and accuracy improve when tibial plateau fractures are classified with an additional 3D model compared with conventional radiology?

METHODS

Between 2012 and 2020, 113 patients with tibial plateau fractures were treated at a Level 1 trauma center. Forty-four patients were excluded based on the presence of bone diseases (such as osteoporosis) and the absence of a CT scan. To increase the chance to detect an improvement or deterioration and to prevent observers from losing focus during the classification, we decided to include 40 patients with tibial plateau fractures. Nine trauma surgeons, eight senior surgical residents, and eight junior surgical residents-none of whom underwent any study-specific pretraining-classified these fractures according to three often-used classification systems (Schatzker, OA/OTA, and the Luo three-column concept), with and without 3D-printed models, and they indicated their overall confidence on a 10-point Likert scale, with 0 meaning not confident at all and 10 absolutely certainty. To set the gold standard, a panel of three experienced trauma surgeons who had special expertise in knee surgery and 10 years to 25 years of experience in practice also classified the fractures until consensus was reached. The Fleiss kappa was used to determine interobserver agreement for fracture classification. Differences in confidence in assessing fractures with and without the 3D-printed model were compared using a paired t-test. Accuracy was calculated by comparing the participants' observations with the gold standard.

RESULTS

The overall interobserver agreement improved minimally for fracture classification according to two of three classification systems (Schatzker: κconv = 0.514 versus κ3Dprint = 0.539; p = 0.005; AO/OTA:κconv = 0.359 versus κ3Dprint = 0.372; p = 0.03). However, none of the classification systems, even when used by our most experienced group of trauma surgeons, achieved more than moderate interobserver agreement, meaning that a large proportion of fractures were misclassified by at least one observer. Overall, there was no improvement in self-assessed confidence in classifying fractures or accuracy with 3D-printed models; confidence was high (about 7 points on a 10-point scale) as rated by all observers, despite moderate or worse accuracy and interobserver agreement.

CONCLUSION

Although 3D-printed models minimally improved the overall interobserver agreement for two of three classification systems, none of the classification systems achieved more than moderate interobserver agreement. This suggests that even with 3D-printed models, many fractures would be misclassified, which could result in misleading communication, inaccurate prognostic assessments, unclear research, and incorrect treatment choices. Therefore, we cannot recommend the use of 3D-printed models in practice and research for classification of tibial plateau fractures.

LEVEL OF EVIDENCE

Level III, diagnostic study.

3D Printing for Complex Cranial Surgery Education: Technical Overview and Preliminary Validation Study

Background 3D printing—also known as additive manufacturing—has a wide range of applications. Reproduction of low-cost, high-fidelity, disease- or patient-specific models presents a key developmental area in simulation and education research for complex cranial surgery.

Methods Using cadaveric dissections as source materials, skull base models were created, printed, and tested for educational value in teaching complex cranial approaches. In this pilot study, assessments were made on the value of 3D printed models demonstrating the retrosigmoid and posterior petrosectomy approaches. Models were assessed and tested in a small cohort of neurosurgery resident subjects (n = 3) using a series of 10 radiographic and 2 printed case examples, with efficacy determined via agreement survey and approach selection accuracy.

Results All subjects indicated agreement or strong agreement for all study endpoints that 3D printed models provided significant improvements in understanding of neuroanatomic relationships and principles of approach selection, as compared to 2D dissections or patient cross-sectional imaging alone. Models were not superior to in-person hands-on teaching. Mean approach selection accuracy was 90% (±13%) for 10 imaging-based cases, or 92% (±7%) overall. Trainees strongly agreed that approach decision-making was enhanced by adjunctive use of 3D models for both radiographic and printed cases.

Conclusion 3D printed models incorporating skull base approaches and/or pathologies provide a compelling addition to the complex cranial education armamentarium. Based on our preliminary analysis, 3D printed models offer substantial potential for pedagogical value as dissection guides, adjuncts to preoperative study and case preparation, or tools for approach selection training and evaluation.

Development and implementation of a three-dimensional (3D) printing elective course for health science students

Three-dimensional (3D) printing technology has become more affordable, accessible, and relevant in healthcare, however, the knowledge of transforming medical images to physical prints still requires some level of training. Anatomy educators can play a pivotal role in introducing learners to 3D printing due to the spatial context inherent to learning anatomy. To bridge this knowledge gap and decrease the intimidation associated with learning 3D printing technology, an elective was developed through a collaboration between the Department of Anatomy and the Makers Lab at the University of California, San Francisco. A self-directed digital resource was created for the elective to guide learners through the 3D printing workflow, which begins with a patient's computed tomography digital imaging and communication in medicine (DICOM) file to a physical 3D printed model. In addition to practicing the 3D printing workflow during the elective, a series of guest speakers presented on 3D printing applications they utilize in their clinical practice and/or research laboratories. Student evaluations indicated that their intimidation associated with 3D printing decreased, the clinical and research topics were directly applicable to their intended careers, and they enjoyed the autonomy associated with the elective format. The elective and the associated digital resource provided students with the foundational knowledge of 3D printing, including the ability to extract, edit, manipulate, and 3D print from DICOM files, making 3D printing more accessible. The aim of disseminating this work is to help other anatomy educators adopt this curriculum at their institution.

Additive Manufacturing in Orthopedics: A Review

Additive manufacturing is an advanced manufacturing manner that seems like the industrial revolution. It has the inborn benefit of producing complex formations, which are distinct from traditional machining technology. Its manufacturing strategy is flexible, including a wide range of materials, and its manufacturing cycle is short. Additive manufacturing techniques are progressively used in bone research and orthopedic operation as more innovative materials are developed. This Review lists the recent research results, analyzes the strengths and weaknesses of diverse three-dimensional printing strategies in orthopedics, and sums up the use of varying 3D printing strategies in surgical guides, surgical implants, surgical predictive models, and bone tissue engineering. Moreover, various postprocessing methods for additive manufacturing for orthopedics are described.

Three-dimensional printing models improves long-term retention in medical education of pathoanatomy: A randomized controlled study

INTRODUCTION

Craniosynostosis is a rare and complex pathology, and visuospatial skills are necessary for a good understanding of the condition. While the use of three-dimensional (3D) models has improved the understanding of complex craniofacial anatomy, no study has evaluated the impact of this teaching support on long-term retention.

MATERIALS AND METHODS

Our randomized controlled trial was designed to compare the long-term retention of information with 3D-printed models of four types of craniosynostosis versus classic 3D reconstructions displayed in two-dimensional (2D) among undergraduate students. All students benefited from the same standardized course followed by the manipulation of the learning tool associated with the group for 15 minutes. Long-term retention was assessed by the capability to properly recognize different types of craniosynostosis 3 weeks after the course.

RESULTS

Eighty-five students were enrolled. Previous educational achievements and baseline visuospatial skills were similar between the groups. The bivariate analysis showed the mean score in the 3D and 2D groups were 11.32 (2.89) and 8.08 (2.81), respectively (p < 0.0001).

CONCLUSIONS

3D-printed models of structures with spatial complexity such as various craniosynostosis patterns improve significantly medical students' long-term retention, indicating their educational efficacy.

Three-Dimensional Printing Model Enhances Craniofacial Trauma Teaching by Improving Morphologic and Biomechanical Understanding: A Randomized Controlled Study

BACKGROUND

Teaching about craniofacial traumas is challenging given the complexity of the craniofacial anatomy and the necessity for good spatial representation skills. To solve these problems, three-dimensional printing seems to be an appropriate educative material. In this study, the authors conducted a randomized controlled trial. The authors' main objective was to compare the performance of the undergraduate medical students in an examination based on the teaching support: three-dimensionally printed models versus two-dimensional pictures.

METHODS

All participants were randomly assigned to one of two groups using a random number table: the three-dimensionally-printed support group (three-dimensional group) or the two-dimensionally-displayed support group (two-dimensional group). All participants completed a multiple-choice question evaluation questionnaire on facial traumatology (first, a zygomatic bone fracture; then, a double mandible fracture). Sex and potential confounding factors were evaluated.

RESULTS

Four hundred thirty-two fifth-year undergraduate medical students were enrolled in this study. Two hundred six students were allocated to the three-dimensional group, and 226 were allocated to the two-dimensional group. The three-dimensionally printed model was considered to be a better teaching material compared with two-dimensional support. The global mean score was 2.36 in the three-dimensional group versus 1.99 in the two-dimensional group (p = 0.008). Regarding teaching of biomechanical aspects, three-dimensionally-printed models provide better understanding (p = 0.015). Participants in both groups exhibited similar previous student educational achievements and visuospatial skills.

CONCLUSIONS

This prospective, randomized, controlled educational trial demonstrated that incorporation of three-dimensionally-printed models improves medical students' understanding. This trial reinforces previous studies highlighting academic benefits in using three-dimensionally-printed models mostly in the field of understanding complex structures.

Dental students' perceptions on a simulated practice using patient-based customised typodonts during the transition from preclinical to clinical education

PURPOSE/OBJECTIVES

Dental students experience difficulties during the transition from preclinical to clinical curriculum. In order to help the students to adapt to the clinical education programme, a simulated practice using patient-based customised models was introduced in this study to prepare for their first clinical practice.

METHODS

This study included 45 third-year predoctoral students (D3 students) who were about to perform the preparation of a single crown abutment on their first patient. After practicing abutment preparation using simulated models and providing the actual treatment to their own patient, the students were surveyed to investigate their perceptions on the simulated practice using the 3D-printed customised typodont model. The statistical analysis of the quantitative data and the thematic analysis of the qualitative data were conducted.

RESULTS

Regarding this simulation, more than 80% of the students gave positive feedback on their practice of (a) operative positions and postures, (b) finger rest, (c) occlusal reduction, (d) axial reduction and (e) proximal reduction. Student responses on the open-ended questions about how they perceived the usefulness of this simulation were categorised as "First clinical case," "Patient-based model" and "Realistic simulation environment." In addition, a number of improvements of the simulation were also suggested by the students including the typodont and the manikin.

CONCLUSIONS

This study gives insights into the significance of simulated practice using patient-based customised typodonts as a transitional education tool and its direction of development in the field of restorative treatments accompanied by irreversible tooth preparations.

An anthropomorphic maxillofacial phantom using 3-dimensional printing, polyurethane rubber and epoxy resin for dental imaging and dosimetry

OBJECTIVE

The aim of this study was to construct an anthropomorphic maxillofacial phantom for dental imaging and dosimetry purposes using three-dimensional (3D) printing technology and materials that simulate the radiographic properties of tissues.

METHODS

Stereolithography photoreactive resins, polyurethane rubber and epoxy resin were modified by adding calcium carbonate and strontium carbonate powders or glass bubbles. These additives were used to change the materials' CT numbers to mimic various body tissues. A maxillofacial phantom was designed using CT images of a head.

RESULTS

Commercial 3D printing resins were found to have CT numbers near 120 HU and were used to print intervertebral discs and an external skin for the maxillofacial phantom. By adding various amounts of calcium carbonate and strontium carbonate powders the CT number of the resin was raised to 1000 & 1500 HU and used to print bone mimics. Epoxy resin modified by adding glass bubbles was used in assembly and as a cartilaginous mimic. Glass bubbles were added to polyurethane rubber to reduce the CT number to simulate soft tissue and filled spaces between the printed anatomy and external skin of the phantom.

CONCLUSION

The maxillofacial phantom designed for dental imaging and dosimetry constructed using 3D printing, polyurethane rubbers and epoxy resins represented a patient anatomically and radiographically. The results of the designed phantom, materials and assembly process can be applied to generate different phantoms that better represent diverse patient types and accommodate different ion chambers.

A new method of intracranial aneurysm modeling for stereolithography apparatus 3D printer: the "Wall-carving technique" using digital imaging and communications in medicine data

PURPOSE

To assess the ability of the "wall-carving (WC) image technique," which uses vascular images from three-dimensional digital subtraction angiograms (3DDSAs). Also, to verify the accuracy of the resulting 3D-printed hollow models of intracranial aneurysms.

METHODS

The 3DDSA data from nine aneurysms were processed to obtain volumetric models suitable for the stereolithography apparatus. The resulting models were filled with iodinated contrast media. 3D rotational angiography of the models was carried out, and the aneurysm geometry was compared with the original patient data. The accuracy of the 3D-printed hollow models' sizes and shapes was evaluated using the nonparametric Wilcoxon signed-rank test and the Dice coefficient index.

RESULTS

The aneurysm volumes ranged from 34.1 to 4609.8 mm³ (maximum diameters 5.1-30.1 mm), and no statistically significant differences were noted between the patient data and the 3D-printed models (p = 0.4). Shape analysis of the aneurysms and related arteries indicated a high level of accuracy (Dice coefficient index value, 88.7-97.3%; mean [± standard deviation (SD)], 93.6% ± 2.5%). The vessel wall thickness of the 3D-printed hollow models was 0.4 mm for the parent and 0.2 mm for small branches and aneurysms, almost the same as the patient data.

CONCLUSION

The WC technique, which involves volume rendering of 3DDSAs, can provide a detailed description of the contrast enhancement of intracranial vessels and aneurysms at arbitrary depths. These models can provide precise anatomic information and be used for simulations of endovascular treatment.

Role of 3D printing technology in paediatric teaching and training: a systematic review

BACKGROUND

In the UK, undergraduate paediatric training is brief, resulting in trainees with a lower paediatric knowledge base compared with other aspects of medicine. With congenital conditions being successfully treated at childhood, adult clinicians encounter and will need to understand these complex pathologies. Patient-specific 3D printed (3DP) models have been used in clinical training, especially for rarer, complex conditions. We perform a systematic review to evaluate the evidence base in using 3DP models to train paediatricians, surgeons, medical students and nurses.

METHODS

Online databases PubMed, Web of Science and Embase were searched between January 2010 and April 2020 using search terms relevant to "paediatrics", "education", "training" and "3D printing". Participants were medical students, postgraduate trainees or clinical staff. Comparative studies (patient-specific 3DP models vs traditional teaching methods) and non-comparative studies were included. Outcomes gauged objective and subjective measures: test scores, time taken to complete tasks, self-reported confidence and personal preferences on 3DP models. If reported, the cost of and time taken to produce the models were noted.

RESULTS

From 587 results, 15 studies fit the criteria of the review protocol, with 5/15 being randomised controlled studies and 10/15 focussing on cardiovascular conditions. Participants using 3DP models demonstrated improved test scores and faster times to complete procedures and identify anatomical landmarks compared with traditional teaching methods (2D diagrams, lectures, videos and supervised clinical events). User feedback was positive, reporting greater user self-confidence in understanding concepts with users wishing for integrated use of 3DP in regular teaching. Four studies reported the costs and times of production, which varied depending on model complexity and printer. 3DP models were cheaper than 'off-the-shelf' models available on the market and had the benefit of using real-world pathologies. These mostly non-randomised and single-centred studies did not address bias or report long-term or clinically translatable outcomes.

CONCLUSIONS

3DP models were associated with greater user satisfaction and good short-term educational outcomes, with low-quality evidence. Multicentred, randomised studies with long-term follow-up and clinically assessed outcomes are needed to fully assess their benefits in this setting.

PROSPERO REGISTRATION NUMBER

CRD42020179656.

Teaching Radial Endobronchial Ultrasound with a Three-Dimensional–printed Radial Ultrasound Model

Background

Peripheral pulmonary lesion (PPL) incidence is rising because of increased chest imaging sensitivity and frequency. For PPLs suspicious for lung cancer, current clinical guidelines recommend tissue diagnosis. Radial endobronchial ultrasound (R-EBUS) is a bronchoscopic technique used for this purpose. It has been observed that diagnostic yield is impacted by the ability to accurately manipulate the radial probe. However, such skills can be acquired, in part, from simulation training. Three-dimensional (3D) printing has been used to produce training simulators for standard bronchoscopy but has not been specifically used to develop similar tools for R-EBUS.

Objective

We report the development of a novel ultrasound-compatible, anatomically accurate 3D-printed R-EBUS simulator and evaluation of its utility as a training tool.

Methods

Computed tomography images were used to develop 3D-printed airway models with ultrasound-compatible PPLs of “low” and “high” technical difficulty. Twenty-one participants were allocated to two groups matched for prior R-EBUS experience. The intervention group received 15 minutes to pretrain R-EBUS using a 3D-printed model, whereas the nonintervention group did not. Both groups then performed R-EBUS on 3D-printed models and were evaluated using a specifically developed assessment tool.

Results

For the “low-difficulty” model, the intervention group achieved a higher score (21.5 ± 2.02) than the nonintervention group (17.1 ± 5.7), reflecting 26% improvement in performance (P = 0.03). For the “high-difficulty” model, the intervention group scored 20.2 ± 4.21 versus 13.3 ± 7.36, corresponding to 52% improvement in performance (P = 0.02). Participants derived benefit from pretraining with the 3D-printed model, regardless of prior experience level.

Conclusion

3D-printing can be used to develop simulators for R-EBUS education. Training using these models significantly improves procedural performance and is effective in both novice and experienced trainees.

Remote Training of Functional Endoscopic Sinus Surgery With Advanced Manufactured 3D Sinus Models and a Telemedicine System

Objective: Traditionally, cadaveric courses have been an important tool in surgical education for Functional Endoscopic Sinus Surgery (FESS). The recent COVID-19 pandemic, however, has had a significant global impact on such courses due to its travel restrictions, social distancing regulations, and infection risk. Here, we report the world-first remote (Functional Endoscopic Sinus Surgery) FESS training course between Japan and Australia, utilizing novel 3D-printed sinus models. We examined the feasibility and educational effect of the course conducted entirely remotely with encrypted telemedicine software.

Methods: Three otolaryngologists in Hokkaido, Japan, were trained to perform frontal sinus dissections on novel 3D sinus models of increasing difficulty, by two rhinologists located in Adelaide, South Australia. The advanced manufactured sinus models were 3D printed from the Computed tomography (CT) scans of patients with chronic rhinosinusitis. Using Zoom and the Quintree telemedicine platform, the surgeons in Adelaide first lectured the Japanese surgeons on the Building Block Concept for a three Dimensional understanding of the frontal recess. They in real time directly supervised the surgeons as they planned and then performed the frontal sinus dissections. The Japanese surgeons were asked to complete a questionnaire pertaining to their experience and the time taken to perform the frontal dissection was recorded. The course was streamed to over 200 otolaryngologists worldwide.

Results: All dissectors completed five frontal sinusotomies. The time to identify the frontal sinus drainage pathway (FSDP) significantly reduced from 1,292 ± 672 to 321 ± 267 s (p = 0.02), despite an increase in the difficulty of the frontal recess anatomy. Image analysis revealed the volume of FSDP was improved (2.36 ± 0.00 to 9.70 ± 1.49 ml, p = 0.014). Questionnaires showed the course's general benefit was 95.47 ± 5.13 in dissectors and 89.24 ± 15.75 in audiences.

Conclusion: The combination of telemedicine software, web-conferencing technology, standardized 3D sinus models, and expert supervision, provides excellent training outcomes for surgeons in circumstances when classical surgical workshops cannot be realized.

Does stereoscopic imaging improve the memorization of medical imaging by neurosurgeons? Experience of a single institution

Stereoscopic imaging has increasingly been used in anatomical teaching and neurosurgery. The aim of our study was to analyze the potential utility of stereoscopic imaging as a tool for memorizing neurosurgical patient cases compared to conventional monoscopic visualization. A total of 16 residents and 6 consultants from the Department of Neurosurgery at Charité – Universitätsmedizin Berlin were recruited for the study. They were divided into two equally experienced groups. A comparative analysis of both imaging modalities was conducted in which four different cases were assessed by the participants. Following the image assessment, two questionnaires, one analyzing the subjective judgment using the 5-point Likert Scale and the other assessing the memorization and anatomical accuracy, were completed by all participants. Both groups had the same median year of experience (5) and stereoacuity (≤ 75 s of arc). The analysis of the first questionnaire demonstrated significant subjective superiority of the monoscopic imaging in evaluation of the pathology (median: monoscopic: 4; stereoscopic: 3; p = 0.020) and in handling of the system (median: monoscopic: 5; stereoscopic: 2; p < 0.001). The second questionnaire showed that the anatomical characterization of the pathologies was comparable between both visualization methods. Most participants rated the stereoscopic visualization as worse compared to the monoscopic visualization, probably due to a lack of familiarity with the newer technique. Stereoscopic imaging, however, was not objectively inferior to traditional monoscopic imaging for anatomical comprehension. Further methodological developments and incorporation in routine clinical workflows will most likely enhance the usability and acceptance of stereoscopic visualization.