Usage of 3D models of tetralogy of Fallot for medical education: impact on learning congenital heart disease

Development of a Cost-Effective 3D-Printed Airway Suction Simulator for Respiratory Therapy Students

BACKGROUND

Three-dimensional (3D)-printed models are cost-effective and can be customized by trainers. This study designed a 3D-printed airway suction simulator for use by respiratory therapy (RT) students. The objective was to demonstrate the cost-effectiveness and application of 3D-printed models in respiratory care training, aiming to enhance the educational experience for RT students.

METHODS

This study developed a 3D-printed airway suction simulator that was cost-effective. A randomized controlled trial was conducted involving RT students to compare effectiveness in a 3D-model group and a control group. Skill assessments and written examinations were used to evaluate the participants' knowledge and skills.

RESULTS

A total of 38 second-year RT students were randomly assigned to either the 3D-model group (n = 19) or the control group (n = 19). One participant in the 3D-model group was lost to follow-up during the planned direct observation of procedural skills (DOPS) assessment and satisfaction questionnaire completion. The posttest written examination scores were significantly higher in the 3D-model group than in the control group (100% vs 80%, P = .02). The scores from the DOPS and satisfaction questionnaire were comparable in the 2 groups.

CONCLUSIONS

This study demonstrated that 3D printing can be used to create a safe and cost-effective airway suction simulator for use by RT students, with potential to enhance training methods. Further research is necessary.

From 2D slices to a 3D model: Training students in digital microanatomy analysis techniques through a 3D printed neuron project

The reconstruction of two-dimensional (2D) slices to three-dimensional (3D) digital anatomical models requires technical skills and software that are becoming increasingly important to the modern anatomist, but these skills are rarely taught in undergraduate science classrooms. Furthermore, learning opportunities that allow students to simultaneously explore anatomy in both 2D and 3D space are increasingly valuable. This report describes a novel learning activity that trains students to digitally trace a serially imaged neuron from a confocal stack and to model that neuron in 3D space for 3D printing. By engaging students in the production of a 3D digital model, this learning activity is designed to provide students a novel way to enhance their understanding of the content, including didactic knowledge of neuron morphology, technical research skills in image analysis, and career exploration of neuroanatomy research. Moreover, students engage with microanatomy in a way that starts in 2D but results in a 3D object they can see, touch, and keep. This discursive article presents the learning activity, including videos, instructional guides, and learning objectives designed to engage students on all six levels of Bloom's Taxonomy. Furthermore, this work is a proof of principle modeling workflow that is approachable, inexpensive, achievable, and adaptable to cell types in other organ systems. This work is designed to motivate the expansion of 3D printing technology into microanatomy and neuroanatomy education.

Application of three-dimensional printing in cardiovascular diseases: a bibliometric analysis

AIM

This paper aimed to explore the application of three-dimensional (3D) printing in cardiovascular diseases, to reach an insight in this field and prospect the future trend.

METHODS

The articles were selected from the Web of Science Core Collection database. Excel 2019, VOSviewer 1.6.16, and CiteSpace 6.1.R6 were used to analyze the information.

RESULTS

A total of 467 papers of 3D printing in cardiovascular diseases were identified, and the first included literature appeared in 2000. A total of 692 institutions from 52 countries participated in the relevant research, while the United States of America contributed to 160 articles and were in a leading position. The most productive institution was Curtin University , and Zhonghua Sun who has posted the most articles ( n =8) was also from there. The Frontiers in Cardiovascular Medicine published most papers ( n =25). The Journal of Thoracic and Cardiovascular Surgery coveted the most citations ( n =520). Related topics of frontiers will still focus on congenital heart disease, valvular heart disease, and left atrial appendage closure.

CONCLUSIONS

The authors summarized the publication information of the application of 3D printing in cardiovascular diseases related literature from 2000 to 2023, including country and institution of origin, authors, and publication journal. This study can reflect the current hotspots and novel directions for the application of 3D printing in cardiovascular diseases.

3D printing in pediatric surgery

Pediatric surgery presents a unique challenge, requiring a specialized approach due to the intricacies of compact anatomy and the presence of distinct congenital features in young patients. Surgeons are tasked with making decisions that not only address immediate concerns but also consider the evolving needs of children as they grow. The advent of three-dimensional (3D) printing has emerged as a valuable tool to facilitate a personalized medical approach. This paper starts by outlining the basics of 3D modeling and printing. We then delve into the transformative role of 3D printing in pediatric surgery, elucidating its applications, benefits, and challenges. The paper concludes by envisioning the future prospects of 3D printing, foreseeing advancements in personalized treatment approaches, improved patient outcomes, and the continued evolution of this technology as an indispensable asset in the pediatric surgical arena.

Evaluating medical undergraduates' and dermatology faculty members' perception of using three-dimensional images as part of dermatology education in a time of COVID-19: a mixed-methods study

BACKGROUND

The coronavirus-19 pandemic has impacted the delivery of medical education in dermatology, leading to decreased patient contact. There arose a need to pioneer innovative teaching tools to augment current methods for now and beyond the pandemic.

OBJECTIVES

We aimed to assess the utility of three-dimensional (3D) images in the learning and teaching of dermatology by analysing the perceptions of medical undergraduates and faculty members in a qualitative and quantitative study.

METHODS

Medical undergraduates (n = 119) and dermatology faculty members (n = 20) were recruited on a voluntary basis to watch a showcase session using a portable 3D imaging system allowing 3D images of skin lesions to be examined and digitally manipulated. After the session, participants filled in an anonymous questionnaire evaluating their perceptions.

RESULTS

Of the 119 learners, most (> 84%) strongly agreed/agreed that (i) they would have more confidence in the field of dermatology; (ii) their ability to describe skin lesions would increase; (iii) their understanding of common dermatological conditions would increase; (iv) 3D images allow a greater approximation to real-life encounters than 2D images; and (v) learning with this modality would be useful. Of the 20 faculty members, most (> 84%) strongly agreed/agreed that (i) it is easier to teach with the aid of 3D images, and (ii) they would want access to 3D images during teaching sessions. Skin tumours were perceived to be learnt best via this modality in terms of showcasing topography (P < 0.01) and close approximation to real-life (P < 0.001). Overall, thematic analysis from qualitative analysis revealed that conditions learnt better with 3D images were those with surface changes and characteristic topography.

CONCLUSIONS

Our results show that the greatest utility of 3D images lies in conditions where lesions have skin surface changes in the form of protrusions or depressions, such as in skin tumours or ulcers. As such, 3D images can be useful teaching tools in dermatology, especially in conditions where appreciation of surface changes and topography is important.

Cardiovascular Computed Tomography in the Diagnosis of Cardiovascular Disease: Beyond Lumen Assessment

Cardiovascular CT is being widely used in the diagnosis of cardiovascular disease due to the rapid technological advancements in CT scanning techniques. These advancements include the development of multi-slice CT, from early generation to the latest models, which has the capability of acquiring images with high spatial and temporal resolution. The recent emergence of photon-counting CT has further enhanced CT performance in clinical applications, providing improved spatial and contrast resolution. CT-derived fractional flow reserve is superior to standard CT-based anatomical assessment for the detection of lesion-specific myocardial ischemia. CT-derived 3D-printed patient-specific models are also superior to standard CT, offering advantages in terms of educational value, surgical planning, and the simulation of cardiovascular disease treatment, as well as enhancing doctor-patient communication. Three-dimensional visualization tools including virtual reality, augmented reality, and mixed reality are further advancing the clinical value of cardiovascular CT in cardiovascular disease. With the widespread use of artificial intelligence, machine learning, and deep learning in cardiovascular disease, the diagnostic performance of cardiovascular CT has significantly improved, with promising results being presented in terms of both disease diagnosis and prediction. This review article provides an overview of the applications of cardiovascular CT, covering its performance from the perspective of its diagnostic value based on traditional lumen assessment to the identification of vulnerable lesions for the prediction of disease outcomes with the use of these advanced technologies. The limitations and future prospects of these technologies are also discussed.

3D Printed Cardiac Models as an Adjunct to Traditional Teaching of Anatomy in Congenital Heart Disease-A Randomised Controlled Study

INTRODUCTION

Three-dimensional (3D) printed cardiac models are increasingly being used for medical education, simulation and training, communication, surgical planning and research. Given the complexities of congenital cardiac anatomy, 3D printing is well suited as an adjunct to traditional teaching methods. This study aims to explore the influence of 3D printed cardiac models as a teaching aid for nurses and paediatric trainees. We hypothesise that using 3D models as an adjunct to didactic teaching methods improves knowledge and confidence levels of participants, regardless of their cardiology experience.

METHOD

A prospective randomised study was performed recruiting paediatric nurses and doctors at a tertiary paediatric hospital. All participants undertook traditional congenital cardiac teaching describing normal cardiac anatomy and seven congenital lesions of increasing complexity (atrial septal defect, ventricular septal defect, vascular ring, partial anomalous pulmonary venous return, tetralogy of Fallot, transposition of the great arteries, and double outlet right ventricle). The intervention group received an additional recorded demonstration while handling 3D printed models of a normal heart and the same lesions. Pre- and post-intervention assessments were completed using a subjective Likert-scale questionnaire and objective multiple-choice examination.

RESULTS

A total of 73 health practitioners (30 cardiac nurses and 43 paediatric trainees) were included. Subjective knowledge and confidence levels substantially improved in the intervention group (both p<0.001), with no differences observed in the control group. Greater improvement in both subjective and objective post-test scores was observed in the intervention group. A pronounced difference between pre- and post-teaching objective examination scores was found in both groups (p=0.002), with larger improvements observed in the intervention group. The mean score in the intervention group after teaching increased by 4.27 (21.4% improvement), as opposed to 2.28 (11.4% improvement) in the control group. There was no difference in pre-test score or post-test improvement based on previous cardiology experience.

DISCUSSION

Three-dimensional (3D) printed cardiac models, when used as an adjunct to traditional teaching methods, substantially improve knowledge and confidence levels of health professionals on a range of congenital cardiac lesions. These models enhance the learners' educational experience and understanding of cardiac anatomy by overcoming the limitation of two-dimensional representations of 3D structures.

3D-Printed Cardiac Models for Fetal Counseling: A Pilot Study and Novel Approach to Improve Communication

A fetal cardiology consultation involves using two-dimensional drawings to explain the cardiac anatomy which can result in inherent variation in how the congenital heart disease (CHD) is conveyed. In this pilot study, we incorporated three-dimensional printed (3DP) models into fetal counseling to demonstrate feasibility and evaluate the impact on parental knowledge, understanding, and anxiety. Parents with a prenatal diagnosis of a muscular ventricular septal defect (VSD) and/or coarctation of aorta were enrolled. Providers were randomized into a Model or Drawing Group and crossed after six months. Parents completed a survey after the consultation which evaluated knowledge of the CHD lesion, expectant surgical management, self-rated understanding, attitude towards the visualization tool, and anxiety. Twenty-nine patients enrolled over a 12 month period. Twelve consultations were done for coarctation of aorta, 13 for VSD, and four for coarctation with a VSD. Both Model and Drawing groups scored similarly in self-reported understanding and confidence, helpfulness of and improvement in communication with the visualization tool. The Model group had higher scores on questions related to the CHD anatomy and surgical intervention [5 [4-5] versus 4 [3.5-5]], p = 0.23 although this didn't reach statistical significance. For the majority (83%) of consultations, the cardiologist agreed that the 3D model improved communication. In this pilot study, we demonstrate the use of 3DP cardiac models during prenatal CHD counseling is feasible and produces results related to parental understanding and knowledge that are equal to and possibly better than the current standard of care.

SDF4CHD: Generative Modeling of Cardiac Anatomies with Congenital Heart Defects

Congenital heart disease (CHD) encompasses a spectrum of cardiovascular structural abnormalities, often requiring customized treatment plans for individual patients. Computational modeling and analysis of these unique cardiac anatomies can improve diagnosis and treatment planning and may ultimately lead to improved outcomes. Deep learning (DL) methods have demonstrated the potential to enable efficient treatment planning by automating cardiac segmentation and mesh construction for patients with normal cardiac anatomies. However, CHDs are often rare, making it challenging to acquire sufficiently large patient cohorts for training such DL models. Generative modeling of cardiac anatomies has the potential to fill this gap via the generation of virtual cohorts; however, prior approaches were largely designed for normal anatomies and cannot readily capture the significant topological variations seen in CHD patients. Therefore, we propose a type- and shape-disentangled generative approach suitable to capture the wide spectrum of cardiac anatomies observed in different CHD types and synthesize differently shaped cardiac anatomies that preserve the unique topology for specific CHD types. Our DL approach represents generic whole heart anatomies with CHD type-specific abnormalities implicitly using signed distance fields (SDF) based on CHD type diagnosis, which conveniently captures divergent anatomical variations across different types and represents meaningful intermediate CHD states. To capture the shape-specific variations, we then learn invertible deformations to morph the learned CHD type-specific anatomies and reconstruct patient-specific shapes. Our approach has the potential to augment the image-segmentation pairs for rarer CHD types for cardiac segmentation and generate cohorts of CHD cardiac meshes for computational simulation.

An Opportunity to See the Heart Defect Physically: Medical Student Experiences of Technology-Enhanced Learning with 3D Printed Models of Congenital Heart Disease

Three-dimensional (3D) printing is increasingly used in medical education and paediatric cardiology. A technology-enhanced learning (TEL) module was designed to accompany 3D printed models of congenital heart disease (CHD) to aid in the teaching of medical students. There are few studies evaluating the attitudes and perceptions of medical students regarding their experience of learning about CHD using 3D printing. This study aimed to explore senior medical students' experiences in learning about paediatric cardiology through a workshop involving 3D printed models of CHD supported by TEL in the form of online case-based learning. A mixed-methods evaluation was undertaken involving a post-workshop questionnaire (n = 94 students), and focus groups (n = 16 students). Focus group and free-text questionnaire responses underwent thematic analysis. Questionnaire responses demonstrated widespread user satisfaction; 91 (97%) students agreed that the workshop was a valuable experience. The highest-level satisfaction was for the physical 3D printed models, the clinical case-based learning, and opportunity for peer collaboration. Thematic analysis identified five key themes: a variable experience of prior learning, interplay between physical and online models, flexible and novel workshop structure, workshop supported the learning outcomes, and future opportunities for learning using 3D printing. A key novel finding was that students indicated the module increased their confidence to teach others about CHD and recommended expansion to other parts of the curriculum. 3D printed models of CHD are a valuable learning resource and contribute to the richness and enjoyment of medical student learning, with widespread satisfaction.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40670-023-01840-w.

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.

Utilization of Simulation to Teach Cardiac Auscultation: A Systematic Review

This systematic review, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, evaluates the effectiveness of simulation-based education in teaching cardiac auscultation. A team of researchers conducted a comprehensive, systematic search of the PubMed database from 2010 to 2021, focusing on cardiac auscultation, education, proficiency, and students. After rigorous filtering, a total of 14 articles, primarily involving medical students and residents, met the inclusion criteria. The articles were categorized based on their focus areas: diagnostic accuracy, knowledge acquisition, competency, and learner satisfaction. Findings suggest that the majority of the studies (86% or 12 out of 14) reported positive outcomes of using simulation for teaching cardiac auscultation, demonstrating improvements in the identified focus areas across diverse contexts. The review underscores the need for future research to further standardize simulation teaching practices, aiming to reduce costs, improve usability, and possibly incorporate multiple simulation approaches in a universal educational process. This approach could enhance outcomes across varied fields and learning styles.

3D printing of foetal vascular rings: feasibility and applicability

BACKGROUND

Vascular rings (VRs) exhibit complex and diverse forms that are difficult to conceptualize using traditional two-dimensional (2D) schematic. Inexperienced medical students and parents who lack a medical technology background face significant challenges in understanding VRs. The purpose of this research is to develop three-dimensional (3D) printing models of VRs to provide new technical imaging support for medical education and parental consultation.

METHODS

This study included 42 fetuses diagnosed as VRs. Foetal echocardiography, modeling and 3D printing were performed, and the dimensional accuracy of models was analyzed. The value of 3D printing in the teaching of VRs was analyzed based on comparing the test results before and after the teaching intervention of 48 medical students and the satisfaction survey. A brief survey was conducted to 40 parents to assess the value of the 3D printed model in prenatal consultations.

RESULTS

Forty models of VRs were successfully obtained, which reproduced the anatomical shape of the VRs space with high dimensional accuracy. No differences in the prelecture test results were noted between the 3D printing group and the 2D image group. After the lecture, the knowledge of both groups improved, but the postlecture score and the change in the prelecture versus postlecture score were greater in the 3D printing group, and the subjective satisfaction survey feedback in the 3D printing group was also better (P < 0.05). Similar results were observed from the parental questionnaire, the vast majority of parents have an enthusiastic and positive attitude towards the use of 3D printed models and suggest using them in future prenatal consultations.

CONCLUSIONS

Three-dimensional printing technology providing a new tool for effectively displaying different types of foetal VRs. This tool helps physicians and families understand the complex structure of foetal great vessels, positively impacting medical instruction and prenatal counselling.

Confirmation of Heart Malformations in Fetuses in the First Trimester Using Three-Dimensional Histologic Autopsy

BACKGROUND

We aimed to evaluate the usefulness of three-dimensional (3D) reconstruction of histology slides to confirm congenital heart disease (CHD) detected by first-trimester fetal cardiac ultrasonography. Conventional autopsy is hindered by the small size of the first-trimester fetal heart, and current CHD confirmation studies employ the use of highly specialized and expensive methods.

TECHNIQUE

An extended first-trimester ultrasound examination protocol was used to diagnose fetal heart anomalies. Medical termination of pregnancies was followed by fetal heart extraction. The specimens were sliced, and the histology slides were stained and scanned. The resulting images were processed, and volume rendering was performed using 3D reconstruction software. The volumes were analyzed by a multidisciplinary team of maternal-fetal medicine subspecialists and pathologists and compared with ultrasound examination findings.

EXPERIENCE

Six fetuses with heart malformations were evaluated using histologic 3D imaging: two with hypoplastic left heart syndrome, two with atrioventricular septal defects, one with an isolated ventricular septal defect, and one with transposition of the great arteries. The technique allowed us to confirm ultrasound-detected anomalies and also identified additional malformations.

CONCLUSION

After pregnancy termination or loss, histologic 3D imaging can be used to confirm the presence of fetal cardiac malformations detected during first-trimester ultrasound examination. Additionally, this technique has the potential to refine the diagnosis for counseling regarding recurrence risk and retains the advantages of standard histology.

Patient-Specific 3D-Printed Low-Cost Models in Medical Education and Clinical Practice

3D printing has been increasingly used for medical applications with studies reporting its value, ranging from medical education to pre-surgical planning and simulation, assisting doctor-patient communication or communication with clinicians, and the development of optimal computed tomography (CT) imaging protocols. This article presents our experience of utilising a 3D-printing facility to print a range of patient-specific low-cost models for medical applications. These models include personalized models in cardiovascular disease (from congenital heart disease to aortic aneurysm, aortic dissection and coronary artery disease) and tumours (lung cancer, pancreatic cancer and biliary disease) based on CT data. Furthermore, we designed and developed novel 3D-printed models, including a 3D-printed breast model for the simulation of breast cancer magnetic resonance imaging (MRI), and calcified coronary plaques for the simulation of extensive calcifications in the coronary arteries. Most of these 3D-printed models were scanned with CT (except for the breast model which was scanned using MRI) for investigation of their educational and clinical value, with promising results achieved. The models were confirmed to be highly accurate in replicating both anatomy and pathology in different body regions with affordable costs. Our experience of producing low-cost and affordable 3D-printed models highlights the feasibility of utilizing 3D-printing technology in medical education and clinical practice.

Comparative effectiveness of virtual reality (VR) vs 3D printed models of congenital heart disease in resident and nurse practitioner educational experience

BACKGROUND

Medical trainees frequently note that cardiac anatomy is difficult to conceive within a two dimensional framework. The specific anatomic defects and the subsequent pathophysiology in flow dynamics may become more apparent when framed in three dimensional models. Given the evidence of improved comprehension using such modeling, this study aimed to contribute further to that understanding by comparing Virtual Reality (VR) and 3D printed models (3DP) in medical education.

OBJECTIVES

We sought to systematically compare the perceived subjective effectiveness of Virtual Reality (VR) and 3D printed models (3DP) in the educational experience of residents and nurse practitioners.

METHODS

Trainees and practitioners underwent individual 15-minute teaching sessions in which features of a developmentally typical heart as well as a congenitally diseased heart were demonstrated using both Virtual Reality (VR) and 3D printed models (3DP). Participants then briefly explored each modality before filling out a short survey in which they identified which model (3DP or VR) they felt was more effective in enhancing their understanding of cardiac anatomy and associated pathophysiology. The survey included a binary summative assessment and a series of Likert scale questions addressing usefulness of each model type and degree of comfort with each modality.

RESULTS

Twenty-seven pediatric residents and 3 nurse practitioners explored models of a developmentally typical heart and tetralogy of Fallot pathology. Most participants had minimal prior exposure to VR (1.1 ± 0.4) or 3D printed models (2.1 ± 1.5). Participants endorsed a greater degree of understanding with VR models (8.5 ± 1) compared with 3D Printed models (6.3 ± 1.8) or traditional models of instruction (5.5 ± 1.5) p < 0.001. Most participants felt comfortable with modern technology (7.6 ± 2.1). 87% of participants preferred VR over 3DP.

CONCLUSIONS

Our study shows that, overall, VR was preferred over 3DP models by pediatric residents and nurse practitioners for understanding cardiac anatomy and pathophysiology.

Patient-Specific 3D-Printed Models in Pediatric Congenital Heart Disease

Three-dimensional (3D) printing technology has become increasingly used in the medical field, with reports demonstrating its superior advantages in both educational and clinical value when compared with standard image visualizations or current diagnostic approaches. Patient-specific or personalized 3D printed models serve as a valuable tool in cardiovascular disease because of the difficulty associated with comprehending cardiovascular anatomy and pathology on 2D flat screens. Additionally, the added value of using 3D-printed models is especially apparent in congenital heart disease (CHD), due to its wide spectrum of anomalies and its complexity. This review provides an overview of 3D-printed models in pediatric CHD, with a focus on educational value for medical students or graduates, clinical applications such as pre-operative planning and simulation of congenital heart surgical procedures, and communication between physicians and patients/parents of patients and between colleagues in the diagnosis and treatment of CHD. Limitations and perspectives on future research directions for the application of 3D printing technology into pediatric cardiology practice are highlighted.

Meta-analyzing the efficacy of 3D printed models in anatomy education

Three-dimensional printing models (3DPs) have been widely used in medical anatomy training. However, the 3DPs evaluation results differ depending on such factors as the training objects, experimental design, organ parts, and test content. Thus, this systematic evaluation was carried out to better understand the role of 3DPs in different populations and different experimental designs. Controlled (CON) studies of 3DPs were retrieved from PubMed and Web of Science databases, where the participants were medical students or residents. The teaching content is the anatomical knowledge of human organs. One evaluation indicator is the mastery of anatomical knowledge after training, and the other is the satisfaction of participants with 3DPs. On the whole, the performance of the 3DPs group was higher than that of the CON group; however, there was no statistical difference in the resident subgroup, and there was no statistical difference for 3DPs vs. 3D visual imaging (3DI). In terms of satisfaction rate, the summary data showed that the difference between the 3DPs group (83.6%) vs. the CON group (69.6%) (binary variable) was not statistically significant, with p > 0.05. 3DPs has a positive effect on anatomy teaching, although there are no statistical differences in the performance tests of individual subgroups; participants generally had good evaluations and satisfaction with 3DPs. 3DPs still faces challenges in production cost, raw material source, authenticity, durability, etc. The future of 3D-printing-model-assisted anatomy teaching is worthy of expectation.

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.

Clinical Applications of Mixed Reality and 3D Printing in Congenital Heart Disease

Understanding the anatomical features and generation of realistic three-dimensional (3D) visualization of congenital heart disease (CHD) is always challenging due to the complexity and wide spectrum of CHD. Emerging technologies, including 3D printing and mixed reality (MR), have the potential to overcome these limitations based on 2D and 3D reconstructions of the standard DICOM (Digital Imaging and Communications in Medicine) images. However, very little research has been conducted with regard to the clinical value of these two novel technologies in CHD. This study aims to investigate the usefulness and clinical value of MR and 3D printing in assisting diagnosis, medical education, pre-operative planning, and intraoperative guidance of CHD surgeries through evaluations from a group of cardiac specialists and physicians. Two cardiac computed tomography angiography scans that demonstrate CHD of different complexities (atrial septal defect and double outlet right ventricle) were selected and converted into 3D-printed heart models (3DPHM) and MR models. Thirty-four cardiac specialists and physicians were recruited. The results showed that the MR models were ranked as the best modality amongst the three, and were significantly better than DICOM images in demonstrating complex CHD lesions (mean difference (MD) = 0.76, p = 0.01), in enhancing depth perception (MD = 1.09, p = 0.00), in portraying spatial relationship between cardiac structures (MD = 1.15, p = 0.00), as a learning tool of the pathology (MD = 0.91, p = 0.00), and in facilitating pre-operative planning (MD = 0.87, p = 0.02). The 3DPHM were ranked as the best modality and significantly better than DICOM images in facilitating communication with patients (MD = 0.99, p = 0.00). In conclusion, both MR models and 3DPHM have their own strengths in different aspects, and they are superior to standard DICOM images in the visualization and management of CHD.

Students' learning experiences of three-dimensional printed models and plastinated specimens: a qualitative analysis

BACKGROUND

Traditional cadaveric dissection is declining whilst plastinated and three-dimensional printed (3DP) models are increasingly popular as substitutes to the conventional anatomy teaching and learning methods. It is unclear about the pros and cons of these new tools and how they impact students' learning experiences of anatomy including humanistic values such as respect, care and empathy.  METHODS: Ninety-six students' views were sought immediately after a randomized cross-over study. Pragmatic design was used to investigate the learning experiences of using plastinated and 3DP models of cardiac (in Phase 1, n = 63) and neck (in Phase 2, n = 33) anatomy. Inductive thematic analysis was conducted based on 278 free text comments (related to strengths, weaknesses, things to improve), and focus group (n = 8) transcriptions in full verbatim about learning anatomy with these tools.

RESULTS

Four themes were found: perceived authenticity, basic understanding versus complexity, attitudes towards respect and care, and multimodality and guidance.

CONCLUSIONS

Overall, students perceived plastinated specimens as more real and authentic, thus perceived more respect and care than 3DP models; whereas 3DP models were easy to use and prefered for learning basic anatomy.

3D Printed Models in Cardiovascular Disease: An Exciting Future to Deliver Personalized Medicine

3D printing has shown great promise in medical applications with increased reports in the literature. Patient-specific 3D printed heart and vascular models replicate normal anatomy and pathology with high accuracy and demonstrate superior advantages over the standard image visualizations for improving understanding of complex cardiovascular structures, providing guidance for surgical planning and simulation of interventional procedures, as well as enhancing doctor-to-patient communication. 3D printed models can also be used to optimize CT scanning protocols for radiation dose reduction. This review article provides an overview of the current status of using 3D printing technology in cardiovascular disease. Limitations and barriers to applying 3D printing in clinical practice are emphasized while future directions are highlighted.

Statistical shape modeling reveals the link between right ventricular shape, hemodynamic force, and myocardial function in patients with repaired tetralogy of Fallot

Patients with repaired tetralogy of Fallot (rTOF) can develop chronic pulmonary insufficiency (PI) with right ventricular (RV) dilation, progressive RV dysfunction, and decreased exercise capacity. Pulmonary valve replacement (PVR) can help reduce the amount of PI and RV dilation; however, optimal timing remains controversial; a better understanding of rTOF pathophysiology is of fundamental importance to inform clinical management of patients with rTOF and optimal timing of PVR. In this study, we hypothesize a tight interplay between RV shape, intracardiac biomechanics, and ventricular function in patients with rTOF. To explore this hypothesis and derive quantitative measures, we combined statistical shape modeling with physics-based analysis of in vivo 4D flow data in 36 patients with rTOF. Our study demonstrated for the first time a correlation between regional RV shape variations, hemodynamic forces (HDF), and clinical dysfunction in patients with rTOF. The main findings of this work include 1) general increase in RV size, due to both volume overload and physiological growth, correlated with decrease in strain magnitude in the respective directions, and with increased QRS; 2) regional PI-induced remodeling accounted for ∼10% of the shape variability of the population, and was associated with increased diastolic HDF along the diaphragm-to-right ventricular outflow tract (RVOT) direction, resulting in a net RV deformation along the same direction and decreased tricuspid annular plane systolic excursion (TAPSE); and 3) three shape modes independently correlated with systolic HDF and exercise capacity. Identification of patients based on the shape variations described in this study could help identify those at risk for irreversible dysfunction and guide optimal timing of PVR.NEW & NOTEWORTHY We combine statistical shape modeling with physics-based analysis of 4D flow data to elucidate the interplay between RV shape, hemodynamic forces, and clinical dysfunction in repaired tetralogy of Fallot. We are the first to show that ventricular remodeling is related to hemodynamic force magnitude and direction, global and regional functional parameters, and exercise intolerance. Identification of patients based on the shape variations described in this study could help identify those at risk for irreversible dysfunction.

Modelling and visualization for the analysis and comprehension of the acoustic performance of buildings through the implementation of a building information modelling-based methodology

Technical and technological advances have revolutionised the architecture, engineering, and construction industries in recent decades. Building information modelling (BIM) methodology has become essential in the process of information management and the development of building projects. This study aims to analyse the potential advantages of the implementation of BIM-based models for the acquisition of theoretical and procedural knowledge about building acoustics. This procedure was implemented as part of a problem-solving exercise in Science, Technology, Engineering, and Mathematics (STEM) university degrees. For this purpose, three-dimensional (3D) BIM models were generated to assess the contribution of their implementation in the process of visualization, comprehension, and analysis of the acoustic behaviour of buildings. The participants' experiences and satisfaction with the BIM models were measured through a questionnaire. The results showed a high level of satisfaction among the participants and good potential for the application of 3D models based on BIM methodology for the acquisition of knowledge and practical skills in building acoustics. These results highlight the potential of BIM models to provide information for understanding the procedure followed during data collection in the experimental analysis and to facilitate the understanding of system behavior.

Abnormal Diastolic Hemodynamic Forces: A Link Between Right Ventricular Wall Motion, Intracardiac Flow, and Pulmonary Regurgitation in Repaired Tetralogy of Fallot

Background and Objective

The effect of chronic pulmonary regurgitation (PR) on right ventricular (RV) dysfunction in repaired Tetralogy of Fallot (RTOF) patients is well recognized by cardiac magnetic resonance (CMR). However, the link between RV wall motion, intracardiac flow and PR has not been established. Hemodynamic force (HDF) represents the global force exchanged between intracardiac blood volume and endocardium, measurable by 4D flow or by a novel mathematical model of wall motion. In our study, we used this novel methodology to derive HDF in a cohort of RTOF patients, exclusively using routine CMR imaging.

Methods

RTOF patients and controls with CMR imaging were retrospectively included. Three-dimensional (3D) models of RV were segmented, including RV outflow tract (RVOT). Feature-tracking software (QStrain 2.0, Medis Medical Imaging Systems, Leiden, Netherlands) captured endocardial contours from long/short-axis cine and used to reconstruct RV wall motion. A global HDF vector was computed from the moving surface, then decomposed into amplitude/impulse of three directional components based on reference (Apical-to-Basal, Septal-to-Free Wall and Diaphragm-to-RVOT direction). HDF were compared and correlated against CMR and exercise stress test parameters. A subset of RTOF patients had 4D flow that was used to derive vorticity (for correlation) and HDF (for comparison against cine method).

Results

68 RTOF patients and 20 controls were included. RTOF patients had increased diastolic HDF amplitude in all three directions (p<0.05). PR% correlated with Diaphragm-RVOT HDF amplitude/impulse (r = 0.578, p<0.0001, r = 0.508, p < 0.0001, respectively). RV ejection fraction modestly correlated with global HDF amplitude (r = 0.2916, p = 0.031). VO2-max correlated with Septal-to-Free Wall HDF impulse (r = 0.536, p = 0.007). Diaphragm-to-RVOT HDF correlated with RVOT vorticity (r = 0.4997, p = 0.001). There was no significant measurement bias between Cine-derived HDF and 4D flow-derived HDF by Bland-Altman analysis.

Conclusion

RTOF patients have abnormal diastolic HDF that is correlated to PR, RV function, exercise capacity and vorticity. HDF can be derived from conventional cine, and is a potential link between RV wall motion and intracardiac flow from PR in RTOF patients.

Criss-cross heart three-dimensional printed models in medical education: A multicenter study on their value as a supporting tool to conventional imaging

The utility of three-dimensional (3D) printed models for medical education in complex congenital heart disease (CHD) is sparse and limited. The purpose of this study was to evaluate the utility of 3D printed models for medical education in criss-cross hearts covering a wide range of participants with different levels of knowledge and experience, from medical students, clinical fellows up to senior medical personnel. Study participants were enrolled from four dedicated imaging workshops developed between 2016 and 2019. The study design was a non-randomized cross-over study to evaluate 127 participants' level of understanding of the criss-cross heart anatomy. This was evaluated using the scores obtained following teaching with conventional images (echocardiography and magnetic resonance imaging) versus a 3D printed model learning approach. A significant improvement in anatomical knowledge of criss-cross heart anatomy was observed when comparing conventional imaging test scores to 3D printed model tests [76.9% (61.5%-87.8%) vs. 84.6% (76.9%-96.2%), P < 0.001]. The increase in the questionnaire marks was statistically significant across all academic groups (consultants in pediatric cardiology, fellows in pediatric cardiology, and medical students). Ninety-four percent (120) and 95.2% (121) of the participants agreed or strongly agreed, respectively, that 3D models helped them to better understand the medical images. Participants scored their overall satisfaction with the 3D printed models as 9.1 out of 10 points. In complex CHD such as criss-cross hearts, 3D printed replicas improve the understanding of cardiovascular anatomy. They enhanced the teaching experience especially when approaching medical students.

Combining patient-specific, digital 3D models with tele-education for adolescents with CHD

INTRODUCTION

Adolescents with CHD require transition to specialised adult-centred care. Previous studies have shown that adolescents' knowledge of their medical condition is correlated with transition readiness. Three-dimensional printed models of CHD have been used to educate medical trainees and patients, although no studies have focused on adolescents with CHD. This study investigates the feasibility of combining patient-specific, digital 3D heart models with tele-education interventions to improve the medical knowledge of adolescents with CHD.

METHODS

Adolescent patients with CHD, aged between 13 and 18 years old, were enrolled and scheduled for a tele-education session. Patient-specific digital 3D heart models were created using images from clinically indicated cardiac magnetic resonance studies. The tele-education session was performed using commercially available, web-conferencing software (Zoom, Zoom Video Communications Inc.) and a customised software (Cardiac Review 3D, Indicated Inc.) incorporating an interactive display of the digital 3D heart model. Medical knowledge was assessed using pre- and post-session questionnaires that were scored by independent reviewers.

RESULTS

Twenty-two adolescents completed the study. The average age of patients was 16 years old (standard deviation 1.5 years) and 56% of patients identified as female. Patients had a variety of cardiac defects, including tetralogy of Fallot, transposition of great arteries, and coarctation of aorta. Post-intervention, adolescents' medical knowledge of their cardiac defects and cardiac surgeries improved compared to pre-intervention (p < 0.01).

CONCLUSIONS

Combining patient-specific, digital 3D heart models with tele-education sessions can improve adolescents' medical knowledge and may assist with transition to adult-centred care.

Comparison of blood pool and myocardial 3D printing in the diagnosis of types of congenital heart disease

The study aimed to evaluate the effectiveness of blood pool and myocardial models made by stereolithography in the diagnosis of different types of congenital heart disease (CHD). Two modeling methods were applied in the diagnosis of 8 cases, and two control groups consisting of experts and students diagnosed the cases using echocardiography with computed tomography, blood pool models, and myocardial models. The importance, suitability, and simulation degree of different models were analyzed. The average diagnostic rate before and after 3D printing was used was 88.75% and 95.9% (P = 0.001) in the expert group and 60% and 91.6% (P = 0.000) in the student group, respectively. 3D printing was considered to be more important for the diagnosis of complex CHDs (very important; average, 87.8%) than simple CHDs (very important; average, 30.8%) (P = 0.000). Myocardial models were considered most realistic regarding the structure of the heart (average, 92.5%). In cases of congenital corrected transposition of great arteries, Williams syndrome, coronary artery fistula, tetralogy of Fallot, patent ductus arteriosus, and coarctation of the aorta, blood pool models were considered more effective (average, 92.1%), while in cases of double outlet right ventricle and ventricular septal defect, myocardial models were considered optimal (average, 80%).

The Use of 3-D Models of Echocardiographic Imaging Planes for Teaching Echocardiography Techniques for Use in Dogs and Cats

Echocardiography is an invaluable technique for the diagnosis of heart disease. The aim of this study was to develop 3-D models of healthy and diseased hearts of dogs and cats, and to evaluate their effectiveness in assisting veterinary undergraduates to understand echocardiographic imaging planes. Resin models depicting the main echocardiographic imaging planes of normal hearts were created, as well as example hearts with features of mitral degeneration in dogs and hypertrophic cardiomyopathy in cats. After a theoretical class, fourth-year students were randomly assigned to one of two groups (model group or control group). The model group had access to the 3-D models, along with self-explanatory text about echocardiographic imaging planes; the control group only had access to the self-explanatory text. Both groups were allowed 2 weeks to study their allocated resources, after which the students undertook an assessment to evaluate their learning and completed a questionnaire about their experiences and satisfaction with the respective teaching method. A total of 39 students participated in the study, 19 in the model group and 20 in the control group. Students assigned to the model group spent more time studying (p = 0.0027). The proportion of students who achieved a satisfactory grade in the assessment was 89.5% in the model group and 60% in the control group (p = 0.0449). The 3-D models facilitated, and significantly improved, the identification of cardiac structures and disease-associated abnormalities, and the learning process in general. Additionally, the models seemed to provide greater student motivation for studying echocardiography.

3D-printed heart models for hands-on training in pediatric cardiology - the future of modern learning and teaching?

BACKGROUND

This project aims to develop a new concept in training pediatric cardiologists to meet the requirements of interventional cardiac catheterizations today in terms of complexity and importance. This newly developed hands-on training program is supposed to enable the acquisition of certain skills which are necessary when investigating and treating patients in a catheter laboratory.

METHODS

Based on anonymous CT-scans of pediatric patients' digital 3D heart models with or without cardiac defects were developed and printed three-dimensionally in a flexible material visible under X-ray. Hands-on training courses were offered using models of a healthy heart and the most common congenital heart defects (CHD). An evaluation was performed by quantifying fluoroscopy times (FL-time) and a questionnaire.

RESULTS

The acceptance of theoretical and practical contents within the hands-on training was very positive. It was demonstrated that it is possible to master various steps of a diagnostic procedure and an intervention as well as to practice and repeat them independently which significantly reduced FL-time. The participants stated that the hands-on training led to more confidence in interventions on real patients.

CONCLUSION

With the development of a training module using 3D-printed heart models, basic and advanced training in the field of diagnostic cardiac examinations as well as interventional therapies of CHD is possible. The learning effect for both, practical skills and theoretical understanding, was significant which underlines the importance of integrating such hands-on trainings on 3D heart models in education and practical training.

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.

Translating Imaging Into 3D Printed Cardiovascular Phantoms

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3D printed patient specific phantoms can visualize complex cardiovascular anatomy

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Common imaging modalities for 3D printing are CCT and CMR

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Material jetting/PolyJet and stereolithography are widely used printing techniques

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Standardized validation is warranted to compare different 3D printing technologies

Translation of imaging into 3-dimensional (3D) printed patient-specific phantoms (3DPSPs) can help visualize complex cardiovascular anatomy and enable tailoring of therapy. The aim of this paper is to review the entire process of phantom production, including imaging, materials, 3D printing technologies, and the validation of 3DPSPs. A systematic review of published research was conducted using Embase and MEDLINE, including studies that investigated 3DPSPs in cardiovascular medicine. Among 2,534 screened papers, 212 fulfilled inclusion criteria and described 3DPSPs as a valuable adjunct for planning and guiding interventions (n = 108 [51%]), simulation of physiological or pathological conditions (n = 19 [9%]), teaching of health care professionals (n = 23 [11%]), patient education (n = 3 [1.4%]), outcome prediction (n = 6 [2.8%]), or other purposes (n = 53 [25%]). The most common imaging modalities to enable 3D printing were cardiac computed tomography (n = 131 [61.8%]) and cardiac magnetic resonance (n = 26 [12.3%]). The printing process was conducted mostly by material jetting (n = 54 [25.5%]) or stereolithography (n = 43 [20.3%]). The 10 largest studies that evaluated the geometric accuracy of 3DPSPs described a mean bias <±1 mm; however, the validation process was very heterogeneous among the studies. Three-dimensional printed patient-specific phantoms are highly accurate, used for teaching, and applied to guide cardiovascular therapy. Systematic comparison of imaging and printing modalities following a standardized validation process is warranted to allow conclusions on the optimal production process of 3DPSPs in the field of cardiovascular medicine.

The impact of 3D printed models on spatial orientation in echocardiography teaching

PURPOSE

During our transthoracic echocardiography (TTE) courses, medical students showed difficulty in spatial orientation. We implemented the use of 3D printed cardiac models of standard TTE views PLAX, PSAX, and A4C and assessed their efficacy in TTE-teaching.

METHODS

One hundred fifty-three participants were split into two groups. A pre-test-retest of anatomy, 2D -, and 3D orientation was conducted. The intervention group (n = 77) was taught using 3D models; the control group (n = 76) without. Both were comparable with respect to baseline parameters. Besides test-scores, a Likert scale recorded experiences, difficulties, and evaluation of teaching instruments.

RESULTS

From the 153 students evaluated, 123 improved, 20 did worse, and ten achieved the same result after the course. The median overall pre-test score was 29 of 41 points, and the retest score was 35 (p < 0.001). However, the intervention group taught with the 3D models, scored significantly better overall (p = 0.016), and in 2D-thinking (p = 0.002) and visual thinking (p = 0.006) subtests. A backward multivariate linear regression model revealed that the 3D models are a strong individual predictor of an excellent visual thinking score. In addition, our study showed that students with difficulty in visual thinking benefited considerably from the 3D models.

CONCLUSION

Students taught using the 3D models significantly improved when compared with conventional teaching. Students regarded the provided models as most helpful in their learning process. We advocate the implementation of 3D-printed heart models featuring the standard views for teaching echocardiography. These findings may be transferable to other evidence based medical and surgical teaching interventions.

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.

Computational Modeling of Right Ventricular Motion and Intracardiac Flow in Repaired Tetralogy of Fallot

PURPOSE

Patients with repaired Tetralogy of Fallot (rTOF) will develop dilation of the right ventricle (RV) from chronic pulmonary insufficiency and require pulmonary valve replacement (PVR). Cardiac MRI (cMRI) is used to guide therapy but has limitations in studying novel intracardiac flow parameters. This pilot study aimed to demonstrate feasibility of reconstructing RV motion and simulating intracardiac flow in rTOF patients, exclusively using conventional cMRI and an immersed-boundary method computational fluid dynamic (CFD) solver.

METHODS

Four rTOF patients and three normal controls underwent cMRI including 4D flow. 3D RV models were segmented from cMRI images. Feature-tracking software captured RV endocardial contours from cMRI long-axis and short-axis cine stacks. RV motion was reconstructed via diffeomorphic mapping (Deformetrica, deformetrica.org), serving as the domain boundary for CFD. Fully-resolved direct numerical simulations were performed over several cardiac cycles. Intracardiac vorticity, kinetic energy (KE) and turbulent kinetic energy (TKE) was measured. For validation, RV motion was compared to manual tracings, results of KE were compared between CFD and 4D flow.

RESULTS

Diastolic vorticity and TKE in rTOF patients were 4.12 ± 2.42 mJ/L and 115 ± 27/s, compared to 2.96 ± 2.16 mJ/L and 78 ± 45/s in controls. There was good agreement between RV motion and manual tracings. The difference in diastolic KE between CFD and 4D flow by Bland-Altman analysis was - 0.89910 to 2 mJ/mL (95% limits of agreement: - 1.351 × 10^-2 mJ/mL to 1.171 × 10^-2 mJ/mL).

CONCLUSION

This CFD framework can produce intracardiac flow in rTOF patients. CFD has the potential for predicting the effects of PVR in rTOF patients and improve the clinical indications guided by cMRI.

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.

Feasibility and accuracy of printed models of complex cardiac defects in small infants from cardiac computed tomography

BACKGROUND

Three-dimensional (3-D) printed models are increasingly used to enhance understanding of complex anatomy in congenital heart disease.

OBJECTIVE

To assess feasibility and accuracy of 3-D printed models obtained from cardiac CT scans in young children with complex congenital heart diseases.

MATERIALS AND METHODS

We included children with conotruncal heart anomalies who were younger than 2 years and had a cardiac CT scan in the course of their follow-up. We used cardiac CT scan datasets to generate 3-D models. To assess the models' accuracy, we compared four diameters for each child between the CT images and the printed models, including the largest diameters (D_max) of ventricular septal defects and aortic annulus and their minimal diameters (D_min).

RESULTS

We obtained images from 14 children with a mean age of 5.5 months (range 1-24 months) and a mean weight of 6.7 kg (range 3.4-14.5 kg). We generated 3-D models for all children. Mean measurement difference between CT images and 3-D models was 0.13 mm for D_min and 0.12 mm for D_max for ventricular septal defect diameters, and it was 0.16 mm for D_min and -0.13 mm for D_max for aortic annulus diameter, indicating a non-clinically significant difference.

CONCLUSION

Three-dimensional printed models could be feasibly generated from cardiac CT scans in a small pediatric population with complex congenital heart diseases. This technique is highly accurate and reliably reflects the same structural dimensions when compared to CT source images.

3D Printed Models for Teaching Orbital Anatomy, Anomalies and Fractures

PURPOSE

The aim of this study was to determine the efficacy of using 3D printing models in the learning process of orbital anatomy and pathology by ophthalmology residents.

METHODS

A quasi-experimental study was performed with 24 residents of ophthalmology at Mashhad University of Medical Sciences. Each stratum was randomized into two groups. The educational booklets were distributed, and various forms of orbital 3D models were printed from orbital computed tomography (CT) scans. Knowledge enhancement on the topics was measured by comparing pretest and posttest scores.

RESULTS

Thirteen residents who were trained using traditional methods were deemed the control group; while 11 residents who were trained using the 3D printed models were classed as the intervention group. The control group was younger than the intervention group (P = 0.047). The results showed that there was a statistically significant difference in the total posttest scores between the two groups. Based on the repeated measures of the analysis of variance (ANOVA), score variables were significant between the two groups (P = 0.008). Interestingly, the use of the 3D educational model was more effective and statistically significant with the year one residents as compared to the year two residents (P = 0.002).

CONCLUSION

This study is the first one in Iran quantifying the effects of learning using 3D printed models in medical education. In fact, 3D modeling training is seemingly effective in teaching ophthalmic residents. As residents have never encountered such technology before, their experience using 3D models proved to be satisfactory and had a surprising positive effect on the learning process through visual training.

Tetralogy of Fallot: stent palliation or neonatal repair?

Surgical repair of Tetralogy of Fallot has excellent outcomes, with over 90% of patients alive at 30 years. The ideal time for surgical repair is between 3 and 11 months of age. However, the symptomatic neonate with Tetralogy of Fallot may require earlier intervention: either a palliative intervention (right ventricular outflow tract stent, ductal stent, balloon pulmonary valvuloplasty, or Blalock-Taussig shunt) followed by a surgical repair later on, or a complete surgical repair in the neonatal period. Indications for palliation include prematurity, complex anatomy, small pulmonary artery size, and comorbidities. Given that outcomes after right ventricular outflow tract stent palliation are particularly promising - there is low mortality and morbidity, and consistently increased oxygen saturations and increased pulmonary artery z-scores - it is now considered the first-line palliative option. Disadvantages of right ventricular outflow tract stenting include increased cardiopulmonary bypass time at later repair and the stent preventing pulmonary valve preservation. However, neonatal surgical repair is associated with increased short-term complications and hospital length of stay compared to staged repair. Both staged repair and primary repair appear to have similar long-term mortality and morbidity, but more evidence is needed assessing long-term outcomes for right ventricular outflow tract stent palliation patients.

The usefulness of 3D printed heart models for medical student education in congenital heart disease

BACKGROUND

Three-dimensional (3D) printing technology enables the translation of 2-dimensional (2D) medical imaging into a physical replica of a patient's individual anatomy and may enhance the understanding of congenital heart defects (CHD). We aimed to evaluate the usefulness of a spectrum of 3D-printed models in teaching CHD to medical students.

RESULTS

We performed a prospective, randomized educational procedure to teach fifth year medical students four CHDs (atrial septal defect (ASD, n = 74), ventricular septal defect (VSD, n = 50), coarctation of aorta (CoA, n = 118) and tetralogy of Fallot (ToF, n = 105)). Students were randomized into printing groups or control groups. All students received the same 20 min lecture with projected digital 2D images. The printing groups also manipulated 3D printed models during the lecture. Both groups answered an objective survey (Multiple-choice questionnaire) twice, pre- and post-test, and completed a post-lecture subjective survey. Three hundred forty-seven students were included and both teaching groups for each CHD were comparable in age, sex and pre-test score. Overall, objective knowledge improved after the lecture and was higher in the printing group compared to the control group (16.3 ± 2.6 vs 14.8 ± 2.8 out of 20, p < 0.0001). Similar results were observed for each CHD (p = 0.0001 ASD group; p = 0.002 VSD group; p = 0.0005 CoA group; p = 0.003 ToF group). Students' opinion of their understanding of CHDs was higher in the printing group compared to the control group (respectively 4.2 ± 0.5 vs 3.8 ± 0.4 out of 5, p < 0.0001).

CONCLUSION

The use of 3D printed models in CHD lectures improve both objective knowledge and learner satisfaction for medical students. The practice should be mainstreamed.

3D-Printed Coronary Plaques to Simulate High Calcification in the Coronary Arteries for Investigation of Blooming Artifacts

The diagnostic value of coronary computed tomography angiography (CCTA) is significantly affected by high calcification in the coronary arteries owing to blooming artifacts limiting its accuracy in assessing the calcified plaques. This study aimed to simulate highly calcified plaques in 3D-printed coronary models. A combination of silicone + 32.8% calcium carbonate was found to produce 800 HU, representing extensive calcification. Six patient-specific coronary artery models were printed using the photosensitive polyurethane resin and a total of 22 calcified plaques with diameters ranging from 1 to 4 mm were inserted into different segments of these 3D-printed coronary models. The coronary models were scanned on a 192-slice CT scanner with 70 kV, pitch of 1.4, and slice thickness of 1 mm. Plaque attenuation was measured between 1100 and 1400 HU. Both maximum-intensity projection (MIP) and volume rendering (VR) images (wide and narrow window widths) were generated for measuring the diameters of these calcified plaques. An overestimation of plaque diameters was noticed on both MIP and VR images, with measurements on the MIP images close to those of the actual plaque sizes (<10% deviation), and a large measurement discrepancy observed on the VR images (up to 50% overestimation). This study proves the feasibility of simulating extensive calcification in coronary arteries using a 3D printing technique to develop calcified plaques and generate 3D-printed coronary models.

3D models improve understanding of congenital heart disease

Introduction

Understanding congenital heart disease (CHD) is vital for medical personnel and parents of affected children. While traditional 2D schematics serve as the typical approach used, several studies have shown these models to be limiting in understanding complex structures. Recent world-emphasis has shifted to 3D printed models as a complement to 2D imaging to bridge knowledge and create new opportunities for experiential learning. We sought to systematically compare 3D digital and physical models for medical personnel and parent education compared to traditional methods.

Methods

3D printed and digital models were made out of MRI and CT data for 20 common CHD. Fellows and nurse practitioners used these models to explore intra-cardiac pathologies following traditional teaching. The models were also used for parent education in outpatient settings after traditional education. The participants were then asked to fill out a Likert scale questionnaire to assess their understanding and satisfaction with different teaching techniques. These ratings were compared using paired t-tests and Pearson’s correlation.

Results

Twenty-five medical personnel (18 fellows; 2 nurses; 4 nurse practitioners and one attending) and twenty parents participated in the study. The diagnosis varied from simple mitral valve pathology to complex single ventricle palliation. Parent and medical personnel perceived understanding with digital models was significantly higher than traditional (p = 0.01). Subjects also felt that physical models were overall more useful than digital ones (p = 0.001). Physicians using models for parent education also perceived the models to be useful, not significantly impacting their clinical workflow.

Conclusions

3D models, both digital and printed, enhance medical personnel and parental perceived understanding of CHD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41205-021-00115-7.