"Let's get physical": advantages of a physical model over 3D computer models and textbooks in learning imaging anatomy

Digitalização e Impressão Tridimensional de Crânio Canino como Ferramenta Educacional para Estudo Anatômico

Este trabalho teve como objetivo padronizar a digitalização e impressão 3D de crânios de cães para uso educacional e avaliar a eficácia de modelos anatômicos impressos na disciplina de anatomia do curso de medicina veterinária. Os crânios foram selecionados para escaneamento e criação dos modelos impressos 3D modelados por fusão de deposição (FDM) utilizando acrilonitrila butadieno estireno. Após uma aula teórica sobre anatomia do crânio os modelos impressos 3D e os modelos reais do crânio de cães foram apresentados aos 140 alunos durante a aula prática de ossos. Uma avaliação prática de osteologia foi realizada após um mês que consistiu na identificação de estruturas anatômicas dos ossos do crânio identificados por alfinetes. Os alunos foram divididos em duas turmas para a realização da avaliação; o primeiro grupo fez os testes usando os crânios reais, enquanto o segundo grupo os crânios impressos 3D. O desempenho dos alunos foi avaliado conforme as suas performances no exame prático. No final da disciplina, eles foram convidados a responder a um breve questionário sobre suas experiências individuais. Os resultados do estudo demonstram que as estruturas anatômicas dos crânios impressos 3D eram semelhantes aos crânios reais. Não houve diferença significativa quando se analisou o grau de acertos e erros durante a realização do exame entre aqueles que identificaram as estruturas nos crânios reais ou nos impressos 3D. Conclui-se que é possível construir um acervo dinâmico digital e impresso tridimensional (3D) para estudos da anatomia comparada da espécie canina a partir de crânios reais, e que os crânios 3D podem ser usados como uma excelente ferramenta alternativa ao ensino na anatomia veterinária.

Development of a Multi-Material 3D Printer for Functional Anatomic Models

Anatomic models are important in medical education and pre-operative planning as they help students or doctors prepare for real scenarios in a risk-free way. Several experimental anatomic models were made with additive manufacturing techniques to improve geometric, radiological, or mechanical realism. However, reproducing the mechanical behavior of soft tissues remains a challenge. To solve this problem, multi-material structuring of soft and hard materials was proposed in this study, and a three-dimensional (3D) printer was built to make such structuring possible. The printer relies on extrusion to deposit certain thermoplastic and silicone rubber materials. Various objects were successfully printed for testing the feasibility of geometric features such as thin walls, infill structuring, overhangs, and multi-material interfaces. Finally, a small medical image-based ribcage model was printed as a proof of concept for anatomic model printing. The features enabled by this printer offer a promising outlook on mimicking the mechanical properties of various soft tissues.

Three-Dimensional Virtual and Printed Prototypes in Complex Congenital and Pediatric Cardiac Surgery-A Multidisciplinary Team-Learning Experience

Three-dimensional (3D) virtual modeling and printing advances individualized medicine and surgery. In congenital cardiac surgery, 3D virtual models and printed prototypes offer advantages of better understanding of complex anatomy, hands-on preoperative surgical planning and emulation, and improved communication within the multidisciplinary team and to patients. We report our single center team-learning experience about the realization and validation of possible clinical benefits of 3D-printed models in surgical planning of complex congenital cardiac surgery. CT-angiography raw data were segmented into 3D-virtual models of the heart-great vessels. Prototypes were 3D-printed as rigid "blood-volume" and flexible "hollow". The accuracy of the models was evaluated intraoperatively. Production steps were realized in the framework of a clinical/research partnership. We produced 3D prototypes of the heart-great vessels for 15 case scenarios (nine males, median age: 11 months) undergoing complex intracardiac repairs. Parity between 3D models and intraoperative structures was within 1 mm range. Models refined diagnostics in 13/15, provided new anatomic information in 9/15. As a team-learning experience, all complex staged redo-operations (13/15; Aristotle-score mean: 10.64 ± 1.95) were rehearsed on the 3D models preoperatively. 3D-printed prototypes significantly contributed to an improved/alternative operative plan on the surgical approach, modification of intracardiac repair in 13/15. No operative morbidity/mortality occurred. Our clinical/research partnership provided coverage for the extra time/labor and material/machinery not financed by insurance. 3D-printed models provided a team-learning experience and contributed to the safety of complex congenital cardiac surgeries. A clinical/research partnership may open avenues for bioprinting of patient-specific implants.

Real Or Not Real: The Impact of the Physical Fidelity of Virtual Learning Resources on Learning Anatomy

Technological advancements have made it possible to create realistic virtual representations of the real world, although it is unclear in medical education whether high physical fidelity is required in virtual learning resources (VLRs). This study, therefore, aimed to compare the effectiveness of high-fidelity (HF) and low-fidelity (LF) VLRs for learning anatomy. For this study, HF and LF VLRs were developed for liver anatomy and participants were voluntarily recruited from two cohorts (cohorts 1 and 2). Knowledge outcomes were measured through pre- and post-tests, task outcomes including activity score and completion time were recorded and participants' perceptions of the VLRs were surveyed. A total of 333 participants (165 HF and 168 LF) took part in this study. Knowledge outcomes were higher for the HF activity in cohort 1 and for the LF activity in cohort 2, although not significantly. There were no significant differences in activity score within either cohort, although completion time was significantly longer for the HF activity in cohort 1 (P = 0.001). There were no significant differences within either cohort in perceptions of the VLRs regarding usefulness for reviewing conceptual knowledge, esthetics, quality, mental effort experienced, or future use, although the LF VLR was scored significantly higher regarding the value for understanding in cohort 1 (P = 0.027).This study suggests that high physical fidelity is not necessarily required for anatomy VLRs, although may potentially be valuable for improving knowledge outcomes. Also, level of prior knowledge may be an important factor when considering the physical fidelity of anatomy VLRs.

Virtual Dissection: An Interactive Anatomy Learning Tool

The novelty of three-dimensional visualization technology (3DVT), such as virtual reality (VR), has captured the interest of many educational institutions. This study's objectives were to (1) assess how VR and physical models impact anatomy learning, (2) determine the effect of visuospatial ability on anatomy learning from VR and physical models, and (3) evaluate the impact of a VR familiarization phase on learning. This within-subjects, crossover study recruited 78 undergraduate students who studied anatomical structures at both physical and VR models and were tested on their knowledge immediately and 48 hours after learning. There were no significant differences in test scores between the two modalities on both testing days. After grouping participants on visuospatial ability, low visuospatial ability learners performed significantly worse on anatomy knowledge tests compared to their high visuospatial ability counterparts when learning from VR immediately (P = 0.001, d = 1.515) and over the long-term (P = 0.003, d = 1.279). In contrast, both low and high visuospatial ability groups performed similarly well when learning from the physical model and tested immediately after learning (P = 0.067) and over the long-term (P = 0.107). These results differ from current literature which indicates that learners with low visuospatial ability are aided by 3DVT. Familiarizing participants with VR before the learning phase had no impact on learning (P = 0.967). This study demonstrated that VR may be detrimental to low visuospatial ability students, whereas physical models may allow all students, regardless of their visuospatial abilities, to learn similarly well.

Applications of 3-dimensional printing in small-animal surgery: A review of current practices

Three-dimensional (3D) printing, also called rapid prototyping or additive manufacturing, transforms digital images into 3D printed objects, typically by layering consecutive thin films of material. This technology has become increasingly accessible to the public, prompting applications in veterinary surgery. Three-dimensional prints provide direct visualization of complex 3D structures and also haptic feedback relevant to surgery. The main objective of this review is to report current applications of 3D printing in small-animal surgery, including surgical education, preoperative planning, and treatment of tissue defects. The reported uses of 3D prints, their proposed advantages, and current limitations are discussed considering published evidence. Aspects of the manufacturing process specific to each application are described, along with current practices in veterinary surgery.

Anatomical Models versus Nontactile Distanced Learning in Otolaryngology Teaching

Introduction  Medical schools in the United Kingdom are under increasing pressure to provide more streamlined, applicable teaching due to rising numbers of trainee doctors but are failing to meet their educational need for otolaryngology. The recent novel coronavirus disease 2019 (COVID-19) pandemic has placed additional pressures on medical schools to adapt the medium over which the curriculum is delivered. The use of tactile learning with three-dimensional models and distanced learning via videoconferencing may provide alternative teaching methods to meet otolaryngology undergraduate learning requirements. This pilot study aimed to assess the differences in undergraduate student attitudes toward tactile learning via nontactile distanced learning and review their acceptability among this cohort.

Methods  Two groups of medical students observed a single educational event on the larynx and management of the airway. The learning opportunity was delivered in a lecture format with the lecturer demonstrating on an anatomical model of the larynx. Group one (tactile group) had an identical model to interact with during the lecture and were present within the lecture theater; group two (nontactile group) did not and observed the lecture via video link. Students were asked to rank their opinion to several statements about the session based on an 11-point Likert's scale and give qualitative feedback.

Results  All ranked feedback was mainly positive. Tactile learning was statistically equivalent to nontactile learning based on the ranked feedback from the students, except for “improvement in anatomical knowledge,” for which the students believed tactile learning was superior ( p  = 0.017). A variety of qualitative feedback was received by both groups.

Conclusion  This pilot study provides evidence for the acceptability among students of the use of nontactile distanced learning to deliver the otolaryngology undergraduate curriculum compared with tactile learning. This can provide the basis for larger studies to assess the educational impact of these different teaching methods.

From CT to 3D Printed Models, Serious Gaming, and Virtual Reality: Framework for Educational 3D Visualization of Complex Anatomical Spaces From Within-the Pterygopalatine Fossa

We describe the framework for capturing the internal view of complex anatomical spaces via multiple media and haptic platforms, exemplified by realistic and conceptual representations of the pterygopalatine fossa (PPF). A realistic three-dimensional (3D) mesh of the PPF was developed by segmenting the osseous anatomy on computed tomography (CT) using Materialize InPrint. Subsequently in Autodesk 3D Studio Max, the realistic mesh was enhanced with graphically designed neurovascular anatomy and additionally a conceptual representation of the PPF with its connections and contents was created. An interactive web-compatible Adobe Flash tutorial using ActionScript was developed, allowing users to advance through a series of educational slides that contained interactive rotatable interior camera views and scrollable CT cross-sectional content, incorporating both the realistic and conceptual models. Both models were also 3D printed using polyamide material. In the realistic model, the neurovasculature was colored with water-based acrylic paint. A 3-piece modular design with embedded magnets allows for internal visualization and seamless assembly. A serious gaming environment of the conceptual PPF was also developed using Truevision3D application programming interface, where users can freely move around rooms and hallways that represent various spaces. Lastly, the realistic model was incorporated into a headset-based virtual reality environment, Surgical Theater, allowing visualization and fly-through inside and outside the model. Multiple 3D techniques for visualization of complex 3D anatomical spaces from within were described, with the necessary software and skills detailed. A rough estimate of the time and cost needed to develop these tools as well as multiple supplementary source and end result files are also made available. Educators could utilize multiple advanced delivery methods to incorporate custom digital 3D models of complex anatomical spaces understood from inside.

Teaching middle ear anatomy using a novel three-dimensional papercraft model

BACKGROUND

The middle ear is a complex anatomical space which is difficult to interpret from two-dimensional imagery. Appropriate surgical knowledge of the area is required to operate, yet current anatomical teaching methods are costly and hard to access for the trainee.

METHODS

A papercraft 3D design involving anatomical elements added separately to a model was designed, and then peer-validated by medical students and junior doctors. Preliminary quantitative assessment was performed using an anatomical labelling questionnaire, with six students given a lecture to act as a control. Qualitative feedback was also gathered.

RESULTS

18 participants were recruited for the study. A total of 12 models were constructed by 6 medical students and 6 junior doctors. 6 medical students received a lecture only. Qualitative feedback was positive and suggested the model improved knowledge and was useful, yet timing and complexity were issues. Students scored, on average, 37% higher after completing the model, with junior doctors also improving anatomical knowledge, though these differences were not significant (p > 0.05).

CONCLUSIONS

In this initial investigation, the model was shown to be an engaging way to learn anatomy, with the tactile and active nature of the process cited as benefits. Construction of the model improved anatomical knowledge to a greater extent than a classical lecture in this study, though this difference was not significant. Further design iterations are required to improve practical utility in the teaching environment, as well as a larger study.

A review and guide to creating patient specific 3D printed anatomical models from MRI for benign gynecologic surgery

Background

Patient specific three-dimensional (3D) models can be derived from two-dimensional medical images, such as magnetic resonance (MR) images. 3D models have been shown to improve anatomical comprehension by providing more accurate assessments of anatomical volumes and better perspectives of structural orientations relative to adjacent structures. The clinical benefit of using patient specific 3D printed models have been highlighted in the fields of orthopaedics, cardiothoracics, and neurosurgery for the purpose of pre-surgical planning. However, reports on the clinical use of 3D printed models in the field of gynecology are limited.

Main text

This article aims to provide a brief overview of the principles of 3D printing and the steps required to derive patient-specific, anatomically accurate 3D printed models of gynecologic anatomy from MR images. Examples of 3D printed models for uterine fibroids and endometriosis are presented as well as a discussion on the barriers to clinical uptake and the future directions for 3D printing in the field of gynecological surgery.

Conclusion

Successful gynecologic surgery requires a thorough understanding of the patient’s anatomy and burden of disease. Future use of patient specific 3D printed models is encouraged so the clinical benefit can be better understood and evidence to support their use in standard of care can be provided.

3D Printing for Cardiovascular Applications: From End-to-End Processes to Emerging Developments

3D printing as a means of fabrication has seen increasing applications in medicine in the last decade, becoming invaluable for cardiovascular applications. This rapidly developing technology has had a significant impact on cardiovascular research, its clinical translation and education. It has expanded our understanding of the cardiovascular system resulting in better devices, tools and consequently improved patient outcomes. This review discusses the latest developments and future directions of generating medical replicas ('phantoms') for use in the cardiovascular field, detailing the end-to-end process from medical imaging to capture structures of interest, to production and use of 3D printed models. We provide comparisons of available imaging modalities and overview of segmentation and post-processing techniques to process images for printing, detailed exploration of latest 3D printing methods and materials, and a comprehensive, up-to-date review of milestone applications and their impact within the cardiovascular domain across research, clinical use and education. We then provide an in-depth exploration of future technologies and innovations around these methods, capturing opportunities and emerging directions across increasingly realistic representations, bioprinting and tissue engineering, and complementary virtual and mixed reality solutions. The next generation of 3D printing techniques allow patient-specific models that are increasingly realistic, replicating properties, anatomy and function.

[Multimodal training concept for temporal bone surgery]

BACKGROUND

Surgical training is increasingly supported by the use of simulators. For temporal bone surgery, shown here by means of mastoidectomy, there are other training models besides cadaver specimens, such as artificial temporal bones or computer-based simulators.

OBJECTIVES

A structured training concept was created which integrates different training methods of mastoidectomy with regard to effectiveness and current learning theory in education.

METHOD

A selective literature research was conducted to compare learning-theoretical findings and the availability and effectiveness of currently existing training models.

RESULTS

To acquire surgical skills, a stepwise approach is suggested. Depending on the progress with computer-based simulation, plastic or native temporal bones should be used. To achieve a plateau of the learning curve, approximately 25 semi-autonomous preparations are recommended. Different 'Objective Structured Assessments of Technical Skills' (OSATS) are implemented to assess the learning progress at different levels.

DISCUSSION

Simulation-based training is recommended until an adequate learning curve plateau is achieved. This is reasonable for patient safety, based on limited accessibility of human cadaveric temporal bones but also by findings of the learning theory.

CONCLUSION

The curriculum integrates different training models of mastoidectomy and OSATS into an overall concept. The training plan has to be continuously adapted to new findings and technical developments.

The production of testis biomodels using three-dimensional (3D) technologies

This study aimed to investigate the potentiality of biomodels to be produced as alternative tools to slaughterhouse materials in andrology education. For this purpose, testis biomodels were produced with reference to bull testes. The biomodel production was carried out by the following steps: the preparation of the reference organs, 3D modelling, and processing of data sets and stages. The biomodels and reference testes were compared in terms of morphological parameters and tonicity. As a result of quantitative measurements, the average length in the reference testicles was 145.56 ± 21.3 mm, while the thickness was 61.94 ± 17.2 mm. The average length, thickness, volume and tonicity values of the biomodels showed similarity to the values of the reference testicles (p > .05). However, it was recorded that the average weight of the reference testicles was determined as 368.07 ± 40.3 g, while the average weight of the biomodels was 69.02 ± 3.18 g (p < .01). As a result, it has been shown that testis biomodels can be successfully produced using three-dimensional technologies. These biomodels are the first examples in the field. We think that the biomodels produced by using innovative technologies should be considered as serious alternatives, which could contribute to the learning processes of students, especially in andrology education.

Virtual Reality Bell-Ringer: The Development and Testing of a Stereoscopic Application for Human Gross Anatomy

As post-secondary education migrates online, developing and evaluating new avenues for assessment in anatomy is paramount. Three-dimensional (3D) visualization technology is one area with the potential to augment or even replace resource-intensive cadaver use in anatomical education. This manuscript details the development of a smartphone application, entitled "Virtual Reality Bell-Ringer (VRBR)," capable of displaying monoscopic two-dimensional (2D) or stereoscopic 3D images with the use of an inexpensive cardboard headset for use in spot examinations. Cadaveric image use, creation, and pinning processes are explained, and the source code is provided. To validate this tool, this paper compares traditional laboratory-based spot examination assessment stations against those administered using the VRBR application to test anatomical knowledge. Participants (undergraduate, n = 38; graduate, n = 13) completed three spot examinations specific to their level of study, one in each of the modalities (2D, 3D, laboratory) as well as a mental rotation test (MRT), Stereo Fly stereotest, and cybersickness survey. Repeated measures ANCOVA suggested participants performed significantly better on laboratory and 3D stations compared to 2D stations. Moderate to severe cybersickness symptoms were reported by 63% of participants in at least one category while using the VRBR application. Highest reported symptoms included: eye strain, general discomfort, difficulty focusing, and difficulty concentrating. Overall, the VRBR application is a promising tool for its portability, affordability, and accessibility. Due to reported cybersickness and other technical limitations, the use of VRBR as an alternative to cadaveric specimens presents several challenges when testing anatomy knowledge that must be addressed before widespread adoption.

The study of screw placement parameters for Ogawa type I acromial fractures by 3D simulation

Background

Acromial fractures are rare and there is no consensus on fixation, but an increasing number of studies have reported using two screws to fix Ogawa type I acromial fractures. The objective of this study was to obtain the ideal length, diameter, insertion point, and angle of the screw using a novel 3D simulation.

Methods

The scapular CT data of 100 individuals were obtained to reconstruct 3D models. The transparency of the 3D model was then downgraded along the axial perspective (the view perpendicular to the cross section of the acromion axis) to find the maximum translucent area. Two virtual screws were placed at the anterior edge of the acromion until they penetrated the posterior cortical bon. The largest diameters and lengths of the screw were measured, and the direction and insertion point of the screw were observed.

Results

The mean maximum lengths of the medial and lateral screws were 43.33 ± 6.17 mm and 39.23 ± 6.01 mm, respectively. The mean maximum diameters of the medial and lateral screws were 4.71 ± 1.23 mm and 4.97 ± 1.07 mm, respectively. Differences in screw length, diameter, and insertion point between males and females were found. The differences in screw angle between sexes were not statistically significant.

Conclusions

Based on a 3D model test, we recommend the size, entry points, and angles of screws for Ogawa type I acromial fractures, providing valuable guidance for clinical work. More accurate screw parameters can be obtained preoperatively by establishing an individualized 3D model.

3D Printed Heart Models Illustrating Myocardial Perfusion Territories to Augment Echocardiography and Electrocardiography Interpretation

Visualizing the vascular territories of coronary arteries during echocardiography or electrocardiography (ECG) requires trainees to mentally relate and overlay 2D sonographic images or cardiac lead projections with 3D anatomical representations of the ventricular walls and their respective blood supply. To facilitate the acquisition of these competencies, this study focuses on the feasibility of developing low-cost, open-sourced 3D printed heart models with standard ultrasound views or ECG lead projections illustrating the myocardial perfusion territories. A 3D digital heart model was cut to reflect the typical cardiac ultrasound views. The 4-chamber view model was further punctured for the paths of the precordial and limb leads of an ECG. Painting coronary arteries on the surface and internal views of the 3D prints illustrated vessel territories. Students, residents, and staff were surveyed during bedside ultrasound simulation sessions and ECG teaching half-days. Results demonstrated clear appreciation of 3D printed models, which suggests such models can easily be implemented by other institutions to augment trainees' experience during skill acquisition.

Examining the Short-, Medium-, and Long-Term Success of an Embodied Learning Activity in the Study of Hand Anatomy for Clinical Application

A student's own body provides an often disregarded site of knowledge production and corporeal wisdom. Learning via cognitive processes anchored in physical movement and body awareness, known as embodied learning, may aid students to visualize structures and understand their functions and clinical relevance. Working from an embodied learning perspective, the current article evaluates the use of an offline physical learning tool (Anatomical Glove Learning System; AGLS) for teaching hand anatomy for clinical application in medical students. Two student samples (N₁  = 105; N₂  = 94) used the AGLS in two different ways. In the first sample, the AGLS was compared to a traditional approach using hand bones, models and prosected specimens. Secondly, the AGLS and traditional approach were combined. The evaluation consisted of three outcomes: short-term learning (post-test), medium-term applications (mock-objective structured clinical examination, MOSCE), and longer-term assessment (objective structured clinical examination, OSCE). Findings from the first sample indicated no significant differences between the AGLS and traditional laboratory groups on short- (F_(1,78) = 0.036, P = 0.849), medium- (F_(1,50) = 0.743, P = 0.393), or longer-term (F_(1,82) = 0.997, P = 0.321) outcomes. In the second sample using the AGLS in combination with a traditional approach was associated with significantly better short-term post-test scores (F_(2,174) = 5.98, P = 0.003) than using the AGLS alone, but demonstrated no effect for long-term OSCE scores. These results suggest an embodied learning experience alone does not appear to be advantageous to student learning, but when combined with other methods for studying anatomy there are learning gains.

The Evolution of Educational Technology in Veterinary Anatomy Education

"All learning is in the learner, not the teacher." Plato was right. The adage has passed the test of time and is still true in an era where technology accompanies us in not only professional but also recreational life every day, everywhere. On the other hand, the learner has evolved and so have the sources being used to satisfy curiosity and learning. It therefore appears intuitive to embrace these technological advances to bring knowledge to our pupils with the aim to facilitate learning and improve performance. It must be clear that these technologies are not intended to replace but rather consolidate knowledge partly acquired during more conventional teaching of anatomy. Veterinary medicine is no outlier. Educating students to the complexity of anatomy in multiple species requires that three-dimensional concepts be taught and understood accurately if appropriate treatment is to be set in place thereafter. Veterinary anatomy education has up to recently walked diligently in the footsteps of John Hunter's medical teaching using specimens, textbooks, and drawings. The discipline has yet to embrace fully the benefits of advancement being made in technology for the benefit of its learners. Three-dimensional representation of anatomy is undeniably a logical and correct way to teach whether it is through the demonstration of cadaveric specimen or alternate reality using smartphones, tablets, headsets or other digital media. Here we review some key aspects of the evolution of educational technology in veterinary anatomy.

Assessing the efficacy of tablet-based simulations for learning pseudo-surgical instrumentation

Nurses and surgeons must identify and handle specialized instruments with high temporal and spatial precision. It is crucial that they are trained effectively. Traditional training methods include supervised practices and text-based study, which may expose patients to undue risk during practice procedures and lack motor/haptic training respectively. Tablet-based simulations have been proposed to mediate some of these limitations. We implemented a learning task that simulates surgical instrumentation nomenclature encountered by novice perioperative nurses. Learning was assessed following training in three distinct conditions: tablet-based simulations, text-based study, and real-world practice. Immediately following a 30-minute training period, instrument identification was performed with comparable accuracy and response times following tablet-based versus text-based training, with both being inferior to real-world practice. Following a week without practice, response times were equivalent between real-world and tablet-based practice. While tablet-based training does not achieve equivalent results in instrument identification accuracy as real-world practice, more practice repetitions in simulated environments may help reduce performance decline. This project has established a technological framework to assess how we can implement simulated educational environments in a maximally beneficial manner.

A guideline for screw fixation of coracoid process base fracture by 3D simulation

BACKGROUND

Fractures of the base of the coracoid process are relatively rare, but an increasing number of studies have reported using screws to fix coracoid process base fractures. This study was performed to simulate the surgical procedure and obtain the ideal diameter, length, insertion point and angle of the screw from a 3-D axial perspective in Chinese patients.

METHODS

We randomly collected right scapula computed tomography (CT) scans from 100 adults. DICOM-formatted CT scan images were imported into Mimics software. A 3D digital model of the right scapula was established. Two virtual cylinders representing two screws were placed from the top of the coracoid process to the neck of the scapula and across the base of the coracoid process to fix the base of the coracoid process. The largest secure diameters and lengths of the virtual screws were measured. The positions of the insertion points and the directions of the screws were also examined.

RESULTS

The screw insertion safe zone can exhibit an irregular fusiform shape according to the reconstructed scapula model. The mean maximum diameters of the medial and lateral screws were 7.08 ± 1.19 mm and 7.34 ± 1.11 mm, respectively. The mean maximum lengths of the medial and lateral screws were 43.11 ± 6.31 mm and 48.16 ± 6.94 mm, respectively. A screw insertion corridor with a diameter of at least 4.5 mm was found in all patients. We found sex-dependent differences in the mean maximum diameters and maximum lengths of the two screws. The positions of the two insertion points were statistically different across sexes.

CONCLUSIONS

The study provides a valuable guideline for determining the largest secure corridor for two screws in fixing a fracture at the base of the coracoid process. For ideal screw placement, we suggest individualised preoperative 3D reconstruction simulations. Further biomechanical studies are needed to verify the function of the screws.

The use of photogrammetric fossil models in palaeontology education

Photogrammetry allows overlapping photographs of fossils to be taken and converted into photo-realistic three-dimensional (3-D) digital models. These models offer potential advantages in teaching palaeontology: they are cheap to produce, can be easily shared and allow the study of rare and delicate specimens. Here I describe approaches for using photogrammetric models in the teaching and learning of palaeontology. Little is known about how students perceive these models and whether they find them valuable in their learning. To address this, first-year university students taught using both fossil specimens and digital models were surveyed about their experience through an anonymous online survey. Most students found that the digital models were easy to use, helped them understand anatomy and were more useful than studying photographs. However, most did not see the models as a substitute for studying real fossils and felt they could learn more from physical models. Digital models are a useful addition to palaeontological education that can supplement real fossils and allow palaeontological education to take place in circumstances where handling of specimens is not possible.

Dry Skulls and Cone Beam Computed Tomography (CBCT) for Teaching Orofacial Bone Anatomy to Undergraduate Dental Students

Learning bone anatomy of the skull is a complex topic involving three-dimensional information. The impact of the use of human dry skulls and cone beam computed tomography (CBCT) imaging was investigated in the teaching of undergraduate dental students. Sixty-four first-year students in the University of Hong Kong were randomly divided into eight groups. Four teaching methods were tested: (1) CBCT followed by standard lecture, (2) CBCT followed by lecture with skulls, (3) standard lecture followed by CBCT, and (4) lecture with skulls followed by CBCT. After each, students were given a multiple-choice questionnaire to assess their objective learning outcome (20 questions) and a questionnaire for their subjective satisfaction (10 statements). Surveys were assessed with Cronbach's alpha, Kendall's tau-b, and principal components analysis. Data were analyzed with Student's t-test and a one-way ANOVA (significance α = 0.05). Standard lecture followed by CBCT showed the highest learning outcome score (81.6% ± 14.1%), but no significant difference was present among four teaching methods. Cone beam computed tomography followed by lecture with skulls scored the highest overall subjective satisfaction (4.9 ± 0.8 out of 6), but no significant difference was present among teaching methods. Nevertheless, students' perception of learning was positively influenced by the use of skulls (P = 0.018). The timing of administration of the CBCT did not affect students' subjective satisfaction or objective learning outcome. Students perceived to learn more by using skulls, but their objective learning outcomes were not significantly affected. A discrepancy seems to exist between students' perception of learning and their effective performance.

3D models of nonunion fractures in long bones as education tools

The appearance of fracture complications can present itself as a difficult scenario in a veterinarian's practice, and it can be difficult to diagnose and have a poor prognosis. The recognition of the different types of nonunion fractures can enable quick guidance on the best way to act, thus reducing the cost of treatment and the patient's suffering. The objective of this study was to create 3D models of nonunion fractures in long bones (3D NUFs). The study was carried out in three stages: 1) creating biscuit models from representations of nonunion fractures; 2) scanning the biscuit models of nonunion fractures and 3D modeling; and 3) printing and finishing the 3D models of nonunion fractures (hereafter, 3D NUFs). The creation of biscuit prototypes and the respective digitalization were decisive in producing 3D NUFs, which reproduced the main characteristics of each type of nonunion fracture classification described in the literature. It took 31.1 hours to create and print all 3D NUFs using 95.66 grams of filament (ABS) for a total cost of $3.73. The creation of 3D NUFs from the biscuit dough presented a new way of obtaining didactic models for the teaching of veterinary medicine. The 3D NUFs represent the different forms of low-cost manifestations that characterize this disease, which can be used as a possible teaching-learning tool for veterinary education.

Instructional Design of Virtual Learning Resources for Anatomy Education

Virtual learning resources (VLRs) developed using immersive technologies like virtual reality are becoming popular in medical education, particularly in anatomy. However, if VLRs are going to be more widely adopted, it is important that they are designed appropriately. The overarching aim of this study was to propose guidelines for the instructional design of VLRs for anatomy education. More specifically, the study grounded these guidelines within cognitive learning theories through an investigation of the cognitive load imposed by VLRs. This included a comparison of stereoscopic and desktop VLR deliveries and an evaluation of the impact of prior knowledge and university experience. Participants were voluntarily recruited to experience stereoscopic and desktop deliveries of a skull anatomy VLR (UNSW Sydney Ethics #HC16592). A MyndBand^® electroencephalography (EEG) headset was used to collect brainwave data and theta power was used as an objective cognitive load measure. The National Aeronautics and Space Administration task load index (NASA-TLX) was used to collect perceptions as a subjective measure. Both objective and subjective cognitive load measures were higher overall for the stereoscopic delivery and for participants with prior knowledge, and significantly higher for junior students (P = 0.038). Based on this study's results, those of several of our previous studies and the literature, various factors are important to consider in VLR design. These include delivery modality, their application to collaborative learning, physical fidelity, prior knowledge and prior university experience. Overall, the guidelines proposed based on these factors suggest that VLR design should be learner-centred and aim to reduce extraneous cognitive load.

Use of color-coded, three-dimensional-printed equine carpus models is preferred by students but does not result in statistically different academic performance

Radiology can be a challenging subject for students and finding new techniques that help improve their understanding could have positive effects in their clinical practice. The purpose of this prospective experimental study was to implement the use of color-coded, three-dimensional-printed, handheld equine carpus models into a radiographic anatomy course and evaluate the impact objectively and subjectively using quizzes and student response surveys. A first-year veterinary class was randomly divided into two similarly sized groups (groups A and B) for an equine normal radiographic anatomy laboratory. Both groups experienced the same laboratory structure; however, each student in group B received a handheld three-dimensional-printed equine carpus. Both groups received a quiz at the end of their laboratory consisting of 10 multiple-choice questions related to the equine carpus. An anonymous survey regarding the laboratory was emailed to students after the laboratory. One week later, the same 10 questions in randomized order were administered via a pop-quiz. Students believed both quizzes would count toward their final course grade. There was no statistically significant difference in grades between groups on either quiz (P > .05). However, based on survey responses, group B students felt the carpus made the laboratory more enjoyable and improved their comprehension of the material, whereas group A students felt the carpus would have increased their enjoyment and improved their comprehension. The implementation of three-dimensional-printed anatomic models may be useful to enhance enjoyment and perceived comprehension of veterinary students; however, there is currently insufficient evidence to suggest these models improve academic performance.

The Impact of Three-Dimensional Printed Anatomical Models on First-Year Student Engagement in a Block Mode Delivery

Student engagement is known to have several positive effects on learning outcomes and can impact a student's university experience. High levels of engagement in content-heavy subjects can be difficult to attain. Due to a major institutional restructure, the anatomy prosection laboratory time per subject was dramatically reduced. In response, the authors set out to redesign their anatomy units with a focus on engaging the learning activities that would increase time-on-task both within and outside of the classroom. One of these curriculum changes was the implementation of a suite of anatomy learning activities centered on sets of three-dimensional printed upper limb skeleton models. A two-part mixed-method sequential exploratory design was used to evaluate these activities. Part one was a questionnaire that evaluated the students' engagement with and perceptions of the models. Part two involved focus groups interviews, which were an extension of the survey questions in part one. The results of the study indicated that the majority of students found the models to be an engaging resource that helped improve their study habits. As a result, students strongly felt that the use of the models inspired greater academic confidence and overall better performance in their assessments. Overall, the models were an effective way of increasing the engagement and deep learning, and reinforced previous findings from the medical education research. Future research should investigate the effects of these models on student's grades within osteopathy and other allied health courses.

Can virtual reality improve traditional anatomy education programmes? A mixed-methods study on the use of a 3D skull model

BACKGROUND

Realistic, portable, and scalable lectures, cadaveric models, 2D atlases and computer simulations are being combined more frequently for teaching anatomy, which result in major increases in user satisfaction. However, although digital simulations may be more portable, interesting, or motivating than traditional teaching tools, whether they are superior in terms of student learning remain unclear. This paper presents a study in which the educational effectiveness of a virtual reality (VR) skull model is compared with that of cadaveric skulls and atlases. The aim of this study was to compare the results of teaching with VR to results of teaching with traditional teaching methods by administering objective questionnaires and perception surveys.

METHODS

A mixed-methods study with 73 medical students was conducted with three different groups, namely, the VR group (N = 25), cadaver group (N = 25) and atlas group (N = 23). Anatomical structures were taught through an introductory lecture and model-based learning. All students completed the pre- and post-intervention tests, which comprised a theory test and an identification test. The theory test consisted of 18 multiple-choice questions, and the identification test consisted of 25 fill-in-the-blank questions.

RESULTS

The participants in all three groups had significantly higher total scores on the post-intervention test than on the pre-intervention test; the post-intervention test score in the VR group was not statistically significantly higher than the post-intervention test score of the other groups (VR: 30 [IQR: 22-33.5], cadaver: 26 [IQR: 20-31.5], atlas: 28[IQR: 20-33]; p > 0.05). The participants in the VR and cadaver groups provided more positive feedback on their learning models than the atlas group (VR: 26 [IQR: 19-30], cadaver: 25 [IQR: 19.5-29.5], atlas: 12 [IQR: 9-20]; p < 0.001).

CONCLUSIONS

The skull virtual learning resource (VLR) was equally efficient as the cadaver skull and atlas in teaching anatomy structures. Such a model can aid individuals in understanding complex anatomical structures with a higher level of motivation and tolerable adverse effects.

Effectiveness of three-dimensional printed and virtual reality models in learning the morphology of craniovertebral junction deformities: a multicentre, randomised controlled study

OBJECTIVES

To compare the effectiveness of three-dimensional printed (3DP), virtual reality (VR) and conventional normal physical (NP) models in clinical education regarding the morphology of craniovertebral junction (CVJ) deformities.

DESIGN

Prospective, multicentre, randomised controlled study.

SETTING

Three teaching hospitals in China.

PARTICIPANTS

One hundred and fifty-three participants in their first year of a 3-year medical residency programme.

INTERVENTIONS

All participants were randomised to one of the three groups to learn the morphology of CVJ deformities using 3DP, VR or NP models.

PRIMARY OUTCOME MEASURES

The objective outcomes were evaluated using three-level objective testing. In the first-level test, the participants were required to identify 15 anatomical landmarks on radiographs without CVJ deformities. In the second-level test, all participants were asked to identify the same 15 landmarks on radiographs showing classic CVJ deformities. In the third-level test, the participants were required to describe the key features of three classic cases of CVJ deformities depicted on radiographs. Each participant was also asked to answer four subjective questions to evaluate the importance and usefulness of the educational materials.

RESULTS

In the first-level test, the 3DP, VR and NP groups achieved similar correct rates. In the second-level test, the correct rate was higher in the 3DP group (82.1%±13.6%) than the VR and NP groups (76.9%±16.9% and 69.9%±20.0%, p=0.002). In the third-level test, the 3DP group achieved better correct rates regarding the description of key CVJ deformities features (66.2%±20.0%, p=0.049) than the other groups. The subjective tests showed that the 3DP model method was considered the most valuable approach for learning CVJ deformities.

CONCLUSIONS

The objective and subjective results show that the 3DP model is more effective teaching instrument than the NP model for learning the pathomorphology of CVJ deformities. The VR model also showed great efficacy, second to 3DP model, in improving participants' understanding of CVJ deformities.

Producing three-dimensional printed models of the hepatobiliary system from computed tomography imaging data

INTRODUCTION

Macroscopic anatomy has traditionally been taught using cadaveric material, lectures and a variety of additional resources including online modules and anatomical models. Traditional plastic models are effective educational tools yet they have significant drawbacks such as a lack of anatomical detail, a lack of texturisation and cost. Three-dimensional printed models stand to solve these problems and widen access to high-quality anatomical teaching. This paper outlines the use of three-dimensional multiplanar imaging (computed tomography) in the development of an accurate model of the hepatobiliary system.

MATERIALS AND METHODS

Computed tomography scans were used to construct a virtual three-dimensional model of the hepatobiliary system. This was printed locally as a full-size colour model. We give a complete account of the process and software used.

DISCUSSION

This study is among the first of a series in which we will document the newly formed Oxford Library of Anatomy. This series will provide the methodology for the production of three-dimensional models from computed tomography and magnetic resonance imaging scans, and the library will provide a complete collection of the most complex anatomical areas. We hope that these models will form an important adjunct in teaching anatomy to medical students and surgical trainees.

Stereoscopic Display Is Superior to Conventional Display for Three-Dimensional Echocardiography of Congenital Heart Anatomy

BACKGROUND

Three-dimensional echocardiography (3DE) improves visualization of cardiac lesions. Current viewing of 3DE studies on a conventional display diminishes the encoded stereoscopic (stereo) information for depth perception. This study aims to evaluate clinician subjective and objective experience of stereo display compared with nonstereo display of 3DE in congenital heart disease.

METHODS

In this prospective study, 22 cardiologists, advanced cardiology trainees, and cardiothoracic surgeons used a commercially available stereo display system with proprietary software to view 10 3DE data sets, alternating between simple and complex lesions. In part A, participants viewed each data set, randomized to 1 minute of stereo display followed by 1 minute of nonstereo display, or vice versa. In part B, participants could freely toggle between stereo and nonstereo display for an additional 90 seconds per data set. Participants answered a series of questions and rated their subjective experience using stereo versus nonstereo display mode on a Likert scale. Objective data on time spent in each display mode during part B and duration of interaction and degree of movement of the 3DE data set in parts A and B were also collected.

RESULTS

All clinician groups found stereo display preferable to nonstereo display of 3DE (P < .0001). Viewing complex lesions was rated lower than simple lesions when using nonstereo display (P < .01). Simple and complex lesions were equally well rated when using stereo display (P = .14). When given a choice of display modes in part B, participants spent more time in stereo display (P < .0001) and interacted more with the 3DE data sets in stereo display (P < .0001).

CONCLUSIONS

Interactive stereoscopic display of 3DE was preferred over conventional nonstereo display by all clinician groups for viewing both simple and complex lesions. This preference is especially true for viewing complex lesions.

A Three-Dimensional Print Model of the Pterygopalatine Fossa Significantly Enhances the Learning Experience

The pterygopalatine fossa (PPF) is a bilateral space deep within the skull that serves as a major neurovascular junction. However, its small volume and poor accessibility make it a difficult space to comprehend using two-dimensional illustrations and cadaveric dissections. A three-dimensional (3D) printed model of the PPF was developed as a visual and kinesthetic learning tool for completely visualizing the fossa, its boundaries, its communicating channels, and its neurovascular structures. The model was evaluated by analyzing student performance on pre- and post-quizzes and a student satisfaction survey based on the five-point Likert scale. The first cohort comprised of 88 students who had never before studied the PPF. The second cohort consisted of 30 students who were previously taught the PPF. Each cohort was randomly divided into a control group who were provided with a half skull and an intervention group that were provided with the 3D printed model. The intervention group performed significantly better on the post-quiz as compared to the control group in cohort I (P = 0.001); while not significant, it also improved learning in cohort II students (P = 0.124). Satisfaction surveys indicated that the intervention group found the 3D printed model to be significantly more useful (P < 0.05) as compared to the half skull used by the control group. Importantly, the effect sizes for cohorts I and II (0.504 and 0.581, respectively) validated the statistical results. Together, this study highlights the importance of 3D printed models as teaching tools in anatomy education.

The Wooden Skull: An Innovation through the Use of Local Materials and Technology to Promote the Teaching and Learning of Human Anatomy

Skeleton models are important in facilitating a student's easy retention and recollection of information in the future. These may assist students carry out hands-on practice in order to acquire and practice new skills that are relevant to first aid. The increasing number of medical institutions and medical students attracts the challenge of inadequate facilitation of the teaching and learning processes. This warrants a study and/or an exploration of an alternative solution such as wooden models in order to solve the problem of scarce and ethically restricted human teaching aids. Wooden pieces (50 cm length × 20 cm diameter) from a Jacaranda mimosifolia tree were prepared for the carving process, and wooden replicas of human skulls were made. Two experimental groups of randomly selected medical students (60: active and 60: control) were separately taught using wooden and natural skull models, respectively. The two groups were assessed and evaluated using the natural skull models to compare their understanding of the anatomy of the skull. Additionally, opinion statements were collected from participants in the active group during the oral examination. Six (6) wooden skull models were produced and used for experimental study. Comparisons of academic scores (mean and median) between active (students using the wooden skull) and control (students using natural skull) groups showed no statistically significant difference (P ≥ 0.05). Concerning the enhancement of learning skills, the wooden model was constructed in a way that would be able to enhance learning as it would be the natural skull. The wooden skull model, with more improvement in structural formation, can adequately facilitate the teaching and learning of anatomy of the human skull. This project and the experimental study about utilization of the wooden skull model provide a good potential of using the wooden models to supplement the use of the natural human skull.

Learning musculoskeletal anatomy through new technologies: a randomized clinical trial

Objective:

to investigate the influence of the application of new methodologies on learning and the motivation of students of the Anatomy discipline.

Method:

randomized, longitudinal, prospective, intervention study. Sixty-two students were recruited to assess the impact of different methodologies. The sample was randomized to compare the results of teaching with a 3D atlas, ultrasound and the traditional method. The parameters were assessed through a satisfaction evaluation questionnaire and anatomical charts. Repeated measures ANOVA was used to determine statistical significance.

Results:

in terms of the usefulness of the seminars, 98.1% of the students considered them to be very positive or positive, stating that they had stimulated their interest in anatomy. The students who learned with the 3D atlas improved their understanding of anatomy (p=0.040). In general, the students improved their grades by around 20%.

Conclusion:

the traditional method combined with new technologies increases the interest of students in human anatomy and enables them to acquire skills and competencies during the learning process.

3D anatomical model for teaching canine lumbosacral epidural anesthesia

Purpose

To develop a 3D anatomical model for teaching canine epidural anesthesia (3DMEA) and to assess its efficacy for teaching and learning prior to the use of live animals.

Methods

The creation of 3DMEA was based on 3D optical scanning and 3D printing of canine bone pieces of the fifth to the seventh lumbar vertebrae, sacrum and pelvis. A total of 20 male dogs were scheduled for castration. 20 veterinary students watched a video showing epidural anesthesia in dogs before the clinical attempt and were assigned to control or 3DMEA groups. Students in the 3DMEA group trained in the model after the video. For the clinical trial, the epidural procedure was performed by students under the veterinary supervision. When observed the absence of response to nociceptive stimuli, the epidural was considered successful. Then, all students answered a questionnaire evaluating the main difficulty founded in the technique and its degree of difficulty.

Results

The 3DMEA group reported a lower degree of difficulty to perform the epidural anesthesia technique when compared with the control group (p=0.0037). The 3DMEA reproduced the anatomical structures, allowing the perception of the distance of needle in relation to the iliac prominences during epidural anesthesia. Its mobility allowed simulation of the animal in standing position and sternal recumbency.

Conclusion

The use of 3DMEA demonstrated greater efficacy in the execution of the technique, being effective in the teaching and learning process before the epidural anesthesia in live animals.

Effect of lesser trochanter posteromedial wall defect on the stability of femoral intertrochanteric fracture using 3D simulation

BACKGROUND

This study investigated the effects of posteromedial fracture fragments on the postoperative stability of intertrochanteric fractures of the femur by analyzing the quantity and range of fragments in CT 3D reconstruction.

MATERIALS AND METHODS

Patients diagnosed with femoral lesser trochanter fractures were collected from September 2015 to February 2018. CT 3D reconstruction was applied to evaluate the quantity and extension of posteromedial fragments and the presence of isolated medial fragments. The stability of postoperative fracture was evaluated by comparing the changes of "neck-shaft angle" and "telescoping" from 1 week to 1 year after operation.

RESULTS

A total of 143 patients were finally confirmed, in which 63 patients contained isolated fragments on the medial side, and the average number of fragments in the posteromedial side was 1.93 ± 0.34, which accounted for an average of about 86.11% ± 8.20% in the whole posteromedial wall. When the number of posteromedial fragments was > 2 and the range of posteromedial fragments was > 75%, then the changes in the neck-shaft angle and "telescoping" showed statistical significance (12.27 ± 4.18 mm and 10.13 ± 6.17°, respectively), and when there were isolated medial isolated fragments, then the change in the neck-shaft angle was 10.66 ± 4.27°, showing statistical significance.

CONCLUSIONS

These findings revealed a certain correlation between the quantity and the range of posteromedial fragments and the postoperative "shortening" and "collapse" of femoral intertrochanteric fractures.

Virtual Reality in Anatomy: A Pilot Study Evaluating Different Delivery Modalities

Technologies such as virtual reality are used in higher education to develop virtual learning resources (VLRs). These VLRs can be delivered in multiple modalities, from truly immersive involving wearable devices to less immersive modalities such as desktop. However, research investigating perceptions of VLRs in anatomy has mainly focused on a single delivery modality and a limited-demographic participant cohort, warranting a comparison of different modalities and a consideration of different cohorts. This pilot study aimed to compare perceptions of highly immersive and less immersive VLR deliveries among anatomy students and tutors and evaluate the impact of prior university experience on students' perceptions of VLRs. A skull anatomy VLR was developed using the Unity^® gaming platform and participants were voluntarily recruited to assess highly immersive stereoscopic and less immersive desktop deliveries of the VLR. A validated survey tool was used to gather perceptions of both deliveries. Most participants agreed that both VLR deliveries were interesting and engaging and provided an immersive experience. Anatomy students perceived the stereoscopic delivery to be significantly more useful for understanding (P = 0.013), while anatomy tutors perceived the desktop delivery as more useful. A degree of physical discomfort and disorientation was reported by some participants for both deliveries, although to a greater extent for the stereoscopic delivery. The stereoscopic delivery was also found to be more mentally taxing than desktop delivery. These results suggest that desktop VLR delivery may minimize the risk of discomfort and disorientation associated with more immersive modalities while still providing a valuable learning experience.

Anatomy Learning from Prosected Cadaveric Specimens Versus Plastic Models: A Comparative Study of Upper Limb Anatomy

Human cadaveric prosections are a traditional, effective, and highly appreciated modality of anatomy learning. Plastic models are an alternative teaching modality, though few studies examine their effectiveness in learning of upper limb musculoskeletal anatomy. The purpose of this study is to investigate which modality is associated with a better outcome, as assessed by students' performance on examinations. Overall, 60 undergraduate medical students without previous knowledge of anatomy participated in the study. Students were assigned into two groups. Group 1 attended lectures and studied from cadaveric prosections (n = 30) and Group 2 attended lectures and used plastic models in the laboratory (n = 30). A knowledge assessment, including examination with tag questions (spot test) and written multiple-choice questions, was held after the end of the study. Students' perceptions were also investigated via an anonymous questionnaire. No significant difference in students' performance was observed between the group using prosections and the group using plastic models (32.2 ± 14.7 vs 35.0 ± 14.8, respectively; P = 0.477). Similarly, no statistically significant difference was found regarding students' satisfaction from using each learning modality (P = 0.441). Plastic models may be a valuable supplementary modality in learning upper limb musculoskeletal anatomy, despite their limitations. Easy to use and with no need for maintaining facilities, they are highly appreciated by students and can be useful when preparing for the use of cadaveric specimens.

Neuroanatomy Learning: Augmented Reality vs. Cross-Sections

Neuroanatomy education is a challenging field which could benefit from modern innovations, such as augmented reality (AR) applications. This study investigates the differences on test scores, cognitive load, and motivation after neuroanatomy learning using AR applications or using cross-sections of the brain. Prior to two practical assignments, a pretest (extended matching questions, double-choice questions and a test on cross-sectional anatomy) and a mental rotation test (MRT) were completed. Sex and MRT scores were used to stratify students over the two groups. The two practical assignments were designed to study (1) general brain anatomy and (2) subcortical structures. Subsequently, participants completed a posttest similar to the pretest and a motivational questionnaire. Finally, a focus group interview was conducted to appraise participants' perceptions. Medical and biomedical students (n = 31); 19 males (61.3%) and 12 females (38.7%), mean age 19.2 ± 1.7 years participated in this experiment. Students who worked with cross-sections (n = 16) showed significantly more improvement on test scores than students who worked with GreyMapp-AR (P = 0.035) (n = 15). Further analysis showed that this difference was primarily caused by significant improvement on the cross-sectional questions. Students in the cross-section group, moreover, experienced a significantly higher germane (P = 0.009) and extraneous cognitive load (P = 0.016) than students in the GreyMapp-AR group. No significant differences were found in motivational scores. To conclude, this study suggests that AR applications can play a role in future anatomy education as an add-on educational tool, especially in learning three-dimensional relations of anatomical structures.

The Critical Role of Stereopsis in Virtual and Mixed Reality Learning Environments

Anatomy education has been revolutionized through digital media, resulting in major advances in realism, portability, scalability, and user satisfaction. However, while such approaches may well be more portable, realistic, or satisfying than traditional photographic presentations, it is less clear that they have any superiority in terms of student learning. In this study, it was hypothesized that virtual and mixed reality presentations of pelvic anatomy will have an advantage over two-dimensional (2D) presentations and perform approximately equal to physical models and that this advantage over 2D presentations will be reduced when stereopsis is decreased by covering the non-dominant eye. Groups of 20 undergraduate students learned pelvic anatomy under seven conditions: physical model with and without stereo vision, mixed reality with and without stereo vision, virtual reality with and without stereo vision, and key views on a computer monitor. All were tested with a cadaveric pelvis and a 15-item, short-answer recognition test. Compared to the key views, the physical model had a 70% increase in accuracy in structure identification; the virtual reality a 25% increase, and the mixed reality a non-significant 2.5% change. Blocking stereopsis reduced performance on the physical model by 15%, on virtual reality by 60%, but by only 2.5% on the mixed reality technology. The data show that virtual and mixed reality technologies tested are inferior to physical models and that true stereopsis is critical in learning anatomy.

Multicenter Advanced Pediatric Otolaryngology Fellowship Prep Surgical Simulation Course with 3D Printed High-Fidelity Models

OBJECTIVE

To assess the effect of 3-dimensional (3D)-printed surgical simulators used in an advanced pediatric otolaryngology fellowship preparatory course on trainee education.

STUDY DESIGN

Quasi-experimental pre/postsurvey.

SETTING

Multicenter collaborative course conducted at a contract research organization prior to a national conference.

SUBJECTS AND METHODS

A 5-station, 7-simulator prep course was piloted for 9 pediatric otolaryngology fellows and 17 otolaryngology senior residents, with simulators for airway graft carving, microtia ear framework carving, and cleft lip/palate repair. Prior to the course, trainees were provided educational materials electronically along with presurveys rating confidence, expertise, and attitude around surgical simulators. In October 2018, surgeons engaged in simulation stations with direction from 2 attending faculty per station, then completed postsurveys for each simulator.

RESULTS

Statistically significant increases (P < .05) in self-reported confidence (average, 53%; range, 18%-80%) and expertise (average, 68%; range, 9%-95%) were seen across all simulators, corresponding to medium to large effect sizes as measured by Cohen's d statistic (0.41-1.71). Positive attitudes around 3D printing in surgical education also demonstrated statistically significant increases (average, 10%; range, 8%-13%). Trainees commented positively on gaining such broad exposure, although consistently indicated a preference for more practice time during the course.

CONCLUSION

We demonstrate the benefit of high-fidelity, 3D-printed simulators in exposing trainees to advanced procedures, allowing them hands-on practice in a zero-risk environment. In the future, we hope to refine this course design, develop standardized tools to assess their educational value, and explore opportunities for integration into use in milestone assessment and accreditation.

Cost-Effective Method for 3-Dimensional Printing Dynamic Multiobject and Patient-Specific Brain Tumor Models: Technical Note

BACKGROUND

Three-dimensional (3D) printing is a powerful tool for replicating patient-specific anatomic features for education and surgical planning. The advent of "desktop" 3D printing has created a cost-effective and widely available means for institutions with limited resources to implement a 3D-printing workflow into their clinical applications. The ability to physically manipulate the desired components of a "dynamic" 3D-printed model provides an additional dimension of anatomic understanding. There is currently a gap in the literature describing a cost-effective and time-efficient means of creating dynamic brain tumor 3D-printed models.

METHODS

Using free, open-access software (3D Slicer) for patient imaging to Standard Tessellation Language file conversion, as well as open access Standard Tessellation Language editing software (Meshmixer), both intraaxial and extraaxial brain tumor models of patient-specific pathology are created.

RESULTS

A step-by-step methodology and demonstration of the software manipulation techniques required for creating cost-effective, multidimensional brain tumor models for patient education and surgical planning are exhibited using a detailed written guide, images, and a video display.

CONCLUSIONS

In this technical note, we describe in detail the specific functions of free, open-access software and desktop 3D printing techniques to create dynamic and patient-specific brain tumor models for education and surgical planning.

Investigation of a three-dimensional printed dynamic cervical spine model for anatomy and physiology education

INTRODUCTION

Three-dimensional (3D) printing of anatomical structures is a growing method of education for students and medical trainees. These models are generally produced as static representations of gross surface anatomy. In order to create a model that provides educators with a tool for demonstration of kinematic and physiologic concepts in addition to surface anatomy, a high-resolution segmentation and 3D-printingtechnique was investigated for the creation of a dynamic educational model.

METHODS

An anonymized computed tomography scan of the cervical spine with a diagnosis of ossification of the posterior longitudinal ligament was acquired. Using a high-resolution thresholding technique, the individual facet and intervertebral spaces were separated, and models of the C3-7 vertebrae were 3D-printed. The models were placed on a myelography simulator and subjected to flexion and extension under fluoroscopy, and measurements of the spinal canal diameter were recorded and compared to in-vivo measurements. The flexible 3D-printed model was then compared to a static 3D-printed model to determine the educational benefit of demonstrating physiologic concepts.

RESULTS

The canal diameter changes on the flexible 3D-printed model accurately reflected in-vivo measurements during dynamic positioning. The flexible model also was also more successful in teaching the physiologic concepts of spinal canal changes during flexion and extension than the static 3D-printed model to a cohort of learners.

CONCLUSIONS

Dynamic 3D-printed models can provide educators with a cost-effective and novel educational tool for not just instruction of surface anatomy, but also physiologic concepts through 3D ex-vivo modeling of case-specific physiologic and pathologic conditions.

Evaluation of the Dimensional Accuracy of 3D-Printed Anatomical Mandibular Models Using FFF, SLA, SLS, MJ, and BJ Printing Technology

With the rapid progression of additive manufacturing and the emergence of new 3D printing technologies, accuracy assessment is mostly being performed on isosymmetric-shaped test bodies. However, the accuracy of anatomic models can vary. The dimensional accuracy of root mean square values in terms of trueness and precision of 50 mandibular replicas, printed with five common printing technologies, were evaluated. The highest trueness was found for the selective laser sintering printer (0.11 ± 0.016 mm), followed by a binder jetting printer (0.14 ± 0.02 mm), and a fused filament fabrication printer (0.16 ± 0.009 mm). However, highest precision was identified for the fused filament fabrication printer (0.05 ± 0.005 mm) whereas other printers had marginally lower values. Despite the statistically significance (p < 0.001), these differences can be considered clinically insignificant. These findings demonstrate that all 3D printing technologies create models with satisfactory dimensional accuracy for surgical use. Since satisfactory results in terms of accuracy can be reached with most technologies, the choice should be more strongly based on the printing materials, the intended use, and the overall budget. The simplest printing technology (fused filament fabrication) always scored high and thus is a reliable choice for most purposes.

Challenges and implementation of the German maternity protection act for female medical students in macroscopic anatomical education

Background: Recent decades have seen controversial discussions on the validity of dissection courses in medical education, with alternative programs tested for various reasons. On April 1, 2015 the classification of formaldehyde as a hazardous substance was upgraded by the EU, leding to some universities precluding the participation of pregnant and breastfeeding students in dissection course. However, the revision to the Maternity Protection Act, implemented in Germany on January 1, 2018, now protects student mothers from being disadvantaged in their studies as a consequence of their pregnancy or breastfeeding. Therefore, universities must offer alternatives to dissection courses using formaldehyde to these female students. Project description: As an alternative to regular dissection courses, which use the abovementioned chemical, the Centre for Anatomy at Charité has opted for developing dedicated courses for student mothers. These new courses use plastinated prosection material instead of formalin-treated cadavers of body donors. As the core of the anatomical education takes place during the third and fourth semester in the current curriculum of human medicine at Charité the alternative courses are limited to those two semesters. Additionally, alternative exams at the end of both semesters had to be developed. The alternative courses were designed to offer pregnant and breastfeeding students a study program as close as possible to the one in which their peers learn human anatomy. Results: For the new courses, plastinates had to be produced and further specimens are still needed. Additionally required sets of bones, models and radiological images were readily available at the Centre for Anatomy. The planning and conceptualization of the courses took half a year of intense preparation. The courses for the third and fourth semester were first running during summer semester 2017. There is a clear demand for courses among pregnant and breastfeeding students. At least 5 student participants per course were registered, corresponding to every fortieth female student in their semester cohorts. The highest number of student participants was 13 in one course so far. The performances of the participants in the anatomical examinations were matching that of students attending the regular courses. Discussion: The alternative macroscopic anatomy courses enable the implementation of the revised Maternity Protection Act. The targeted student group is highly satisfied with the offered alternative courses. Considering the number of participants and their examination performance so far, the Centre for Anatomy regards the efforts involved in planning and implementing the courses as justified. The courses allow pregnant and breastfeeding students to address the same anatomical themes at the same time as their fellow students. However, due to restricted flexibility of plastinates and because students cannot prepare specific anatomical structures independently the scope of topographic learning is limited. That being said, well-produced plastinates can display anatomical structures which often cannot be dissected in regular courses. The alternative macroscopic anatomy courses using plastinates constitute suitable alternatives to the regular dissection courses with formalin-treated cadavers for pregnant and breastfeeding students.

Biomechanical comparison of Thiel embalmed and fresh frozen nerve tissue

The aim of this study was to determine the effect of Thiel embalming on the biomechanical properties of nerve tissue, to validate the use of Thiel embalmed bodies as a reliable model system for obtaining biomechanical data to supplement neurodynamic models, for anesthesiological and neurosurgical training and for future preclinical test set-ups involving nerve tissue. Upon the arrival of a body at the anatomy department, a fresh median nerve was harvested, the harvest site was sutured and following the Thiel embalming procedure the Thiel embalmed median nerve of the opposing wrist was harvested. Micro CT was performed to establish the cross-sectional area and biomechanical tensile testing was performed to compare the Young's modulus/elasticity of fresh frozen and Thiel embalmed nerves. Thiel embalming did not cause a significant difference in elasticity when comparing Thiel embalmed and fresh frozen specimens. A correlation was found between the cross-sectional area of Thiel embalmed nerve specimens and their Young's modulus. Thiel embalming does not significantly alter the elasticity of nerve tissue compared to fresh frozen nerve tissue. Similar shapes were observed when comparing the stress/strain curves of both specimen types. This indicates that Thiel embalmed nerve tissue is a viable alternative for using fresh frozen specimens when investigating biomechanical principles/mechanisms. Some specimens showed a reversed trend in Young's modulus that could be related to slight differences in embalming outcome, so caution is advised when Thiel embalmed specimens are used to obtain raw numerical data for direct application in the clinic.

How Can We Show You, If You Can't See It? Trialing the Use of an Interactive Three-Dimensional Micro-CT Model in Medical Education

Teaching internal structures obscured from direct view is a major challenge of anatomy education. High-fidelity interactive three-dimensional (3D) micro-computed tomography (CT) models with virtual dissection present a possible solution. However, their utility for teaching complex internal structures of the human body is unclear. The purpose of this study was to investigate the use of a realistic 3D micro-CT interactive visualization computer model to teach paranasal sinus anatomy in a laboratory setting during pre-clinical medical training. Year 1 (n = 79) and Year 2 (n = 59) medical students undertook self-directed activities focused on paranasal sinus anatomy in one of two laboratories (traditional laboratory and 3D model). All participants completed pre and posttests before and after the laboratory session. Results of regression analyses predicting post-laboratory knowledge indicate that, when students were inexperienced with the 3D computer technology, use of the model was detrimental to learning for students with greater prior knowledge of the relevant anatomy (P < 0.05). For participants experienced with the 3D computer technology, however, the use of the model was detrimental for students with less prior knowledge of the relevant anatomy (P < 0.001). These results emphasize that several factors need to be considered in the design and effective implementation of such models in the classroom. Under the right conditions, the 3D model is equal to traditional laboratory resources when used as a learning tool. This paper discusses the importance of preparatory training for students and the technical consideration necessary to successfully integrate such models into medical anatomical curricula.

Color Enhancement Strategies for 3D Printing of X-ray Computed Tomography Bone Data for Advanced Anatomy Teaching Models

Three-dimensional (3D) printed anatomical models are valuable visual aids that are widely used in clinical and academic settings to teach complex anatomy. Procedures for converting human biomedical image datasets, like X-ray computed tomography (CT), to prinTable 3D files were explored, allowing easy reproduction of highly accurate models; however, these largely remain monochrome. While multi-color 3D printing is available in two accessible modalities (binder-jetting and poly-jet/multi-jet systems), studies embracing the viability of these technologies in the production of anatomical teaching models are relatively sparse, especially for sub-structures within a segmentation of homogeneous tissue density. Here, we outline a strategy to manually highlight anatomical subregions of a given structure and multi-color 3D print the resultant models in a cost-effective manner. Readily available high-resolution 3D reconstructed models are accessible to the public in online libraries. From these databases, four representative files (of a femur, lumbar vertebra, scapula, and innominate bone) were selected and digitally color enhanced with one of two strategies (painting or splitting) guided by Feneis and Dauber’s Pocket Atlas of Human Anatomy. Resulting models were created via 3D printing with binder-jet and/or poly-jet machines with important features, such as muscle origin and insertion points, highlighted using multiple colors. The resulting multi-color, physical models are promising teaching tools that will enhance the anatomical learning experience.