Dimensional Accuracy and Clinical Value of 3D Printed Models in Congenital Heart Disease: A Systematic Review and Meta-Analysis

Cardiovascular computed tomography in cardiovascular disease: An overview of its applications from diagnosis to prediction

Cardiovascular computed tomography angiography (CTA) is a widely used imaging modality in the diagnosis of cardiovascular disease. Advancements in CT imaging technology have further advanced its applications from high diagnostic value to minimising radiation exposure to patients. In addition to the standard application of assessing vascular lumen changes, CTA-derived applications including 3D printed personalised models, 3D visualisations such as virtual endoscopy, virtual reality, augmented reality and mixed reality, as well as CT-derived hemodynamic flow analysis and fractional flow reserve (FFRCT) greatly enhance the diagnostic performance of CTA in cardiovascular disease. The widespread application of artificial intelligence in medicine also significantly contributes to the clinical value of CTA in cardiovascular disease. Clinical value of CTA has extended from the initial diagnosis to identification of vulnerable lesions, and prediction of disease extent, hence improving patient care and management. In this review article, as an active researcher in cardiovascular imaging for more than 20 years, I will provide an overview of cardiovascular CTA in cardiovascular disease. It is expected that this review will provide readers with an update of CTA applications, from the initial lumen assessment to recent developments utilising latest novel imaging and visualisation technologies. It will serve as a useful resource for researchers and clinicians to judiciously use the cardiovascular CT in clinical practice.

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.

Three-Dimensional Bioprinting in Cardiovascular Disease: Current Status and Future Directions

Three-dimensional (3D) printing plays an important role in cardiovascular disease through the use of personalised models that replicate the normal anatomy and its pathology with high accuracy and reliability. While 3D printed heart and vascular models have been shown to improve medical education, preoperative planning and simulation of cardiac procedures, as well as to enhance communication with patients, 3D bioprinting represents a potential advancement of 3D printing technology by allowing the printing of cellular or biological components, functional tissues and organs that can be used in a variety of applications in cardiovascular disease. Recent advances in bioprinting technology have shown the ability to support vascularisation of large-scale constructs with enhanced biocompatibility and structural stability, thus creating opportunities to replace damaged tissues or organs. In this review, we provide an overview of the use of 3D bioprinting in cardiovascular disease with a focus on technologies and applications in cardiac tissues, vascular constructs and grafts, heart valves and myocardium. Limitations and future research directions are highlighted.

Exploring the value of three-dimensional printing and virtualization in paediatric healthcare: A multi-case quality improvement study

Background

Three-dimensional printing is being utilized in clinical medicine to support activities including surgical planning, education, and medical device fabrication. To better understand the impacts of this technology, a survey was implemented with radiologists, specialist physicians, and surgeons at a tertiary care hospital in Canada, examining multidimensional value and considerations for uptake.

Objectives

To examine how three-dimensional printing can be integrated into the paediatric context and highlight areas of impact and value to the healthcare system using Kirkpatrick's Model. Secondarily, to explore the perspective of clinicians utilizing three-dimensional models and how they make decisions about whether or not to use the technology in patient care.

Methods

A post-case survey. Descriptive statistics are provided for Likert-style questions, and a thematic analysis was conducted to identify common patterns in open-ended responses.

Results

In total, 37 respondents were surveyed across 19 clinical cases, providing their perspectives on model reaction, learning, behaviour, and results. We found surgeons and specialists to consider the models more beneficial than radiologists. Results further showed that the models were more helpful when used to assess the likelihood of success or failure of clinical management strategies, and for intraoperative orientation. We demonstrate that three-dimensional printed models could improve perioperative metrics, including a reduction in operating room time, but with a reciprocal effect on pre-procedural planning time. Clinicians who shared the models with patients and families thought it increased understanding of the disease and surgical procedure, and had no effect on their consultation time.

Conclusions

Three-dimensional printing and virtualization were used in preoperative planning and for communication among the clinical care team, trainees, patients, and families. Three-dimensional models provide multidimensional value to clinical teams, patients, and the health system. Further investigation is warranted to assess value in other clinical areas, across disciplines, and from a health economics and outcomes perspective.

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.

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.

Efficacy of three-dimensional models for medical education: A systematic scoping review of randomized clinical trials

To estimate the efficacy of three-dimensional (3D) models for medical education.

METHODS

A systematic scoping review was performed containing diverse databases such as SCOPUS, PubMed/MEDLINE, SCIELO, and LILACS. MeSH terms and keywords were stipulated to explore randomized clinical trials (RCTs) in all languages. Solely RCTs that accomplished the eligibility criteria were admitted.

RESULTS

Fifteen RCTs including 1659 medical students were chosen. Five RCTs studied heart models, 3 RCTs explored facial, spinal and bone fractures and the rest of the trials investigated eye, arterial, pelvic, hepatic, chest, skull, and cleft lip and palate models. Regarding the efficacy of 3D models, in terms of learning skills and knowledge gained by medical students, most RCTs reported higher scores. Considering the test-taking times, the results were variable. Two RCTs showed less time for the 3D group, another RCT indicated variable results in the response times of the test depending on the anatomical zone evaluated, while another described that the students in the 3D group were slightly quicker to answer all questions when compared with the traditional group, but without statistical significance. The other 11 experiments did not present results about test-taking times. Most students in all RCTs indicated satisfaction, enjoyment, and interest in utilizing the 3D systems, and recognized that their abilities were enhanced.

CONCLUSIONS

Higher efficacy in terms of learning skills and knowledge gained was observed when the 3D systems were used by medical students. Undergraduates also expressed great satisfaction with the use of these technologies. Regarding the test-taking times, the results favored the 3D group.

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.

Three-dimensional printing and virtual reconstruction in surgical planning of double-outlet right ventricle repair

Objectives

For more than a decade, 3-dimensional (3D) printing has been identified as an innovative tool for the surgical planning of double-outlet right ventricle (DORV). Nevertheless, lack of evidence concerning its benefits encourages us to identify valuable criteria for future prospective trials.

Methods

We conducted a retrospective study involving 10 patients with DORV operated between 2015 and 2019 in our center. During a preoperative multidisciplinary heart team meeting, we harvested surgical decisions following a 3-increment step process: (1) multimodal imaging; (2) 3D virtual valvular reconstruction (3DVVR); and (3) 3D-printed heart model (3DPHM). The primary outcome was the proportion of predicted surgical strategy following each of the 3 steps, compared with the institutional retrospective surgical strategy. The secondary outcome was the change of surgical strategy through 3D modalities compared with multimodal imaging. The incremental benefit of the 3DVVR and 3DPHM over multimodal imaging was then assessed.

Results

The operative strategy was predicted in 5 cases after multimodal imaging, in 9 cases after 3DVVR, and the 10 cases after 3DPHM. Compared with multimodal imaging, 3DVVR modified the strategy for 4 cases. One case was correctly predicted only after 3DPHM inspection.

Conclusions

3DVVR and 3DPHM improved multimodal imaging in the surgical planning of patients with DORV. 3DVVR allowed a better appreciation of the relationships between great vessels, valves, and ventricular septal defects. 3DPHM offers a realistic preoperative view at patient scale and enhances the evaluation of outflow tract obstruction. Our retrospective study demonstrates benefits of preoperative 3D modalities and supports future prospective trials to assess their impact on postoperative outcomes.

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.

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.

Three-Dimensional Printed Models of the Heart Represent an Opportunity for Inclusive Learning

Three-dimensional (3D) printed models of anatomic structures offer an alternative to studying manufactured, "idealized" models or cadaveric specimens. The utility of 3D printed models of the heart for clinical veterinary students learning echocardiographic anatomy is unreported. This study aimed to assess the feasibility and utility of 3D printed models of the canine heart as a supplementary teaching aid in final-year vet students. We hypothesized that using 3D printed cardiac models would improve test scores and feedback when compared with a control group. Students (n = 31) were randomized to use either a video guide to echocardiographic anatomy alongside 3D printed models (3DMs) or video only (VO). Prior to a self-directed learning session, students answered eight extended matching questions as a baseline knowledge assessment. They then undertook the learning session and provided feedback (Likert scores and free text). Students repeated the test within 1 to 3 days. Changes in test scores and feedback were compared between 3DM and VO groups, and between track and non-track rotation students. The 3DM group had increased test scores in the non-track subgroup. Track students' test scores in the VO group increased, but not in the 3DM group. Students in the 3DM group had a higher completion rate, and more left free-text feedback. Feedback from 3DM was almost universally positive, and students believed more strongly that these should be used for future veterinary anatomy teaching. In conclusion, these pilot data suggest that 3D printed canine cardiac models are feasible to produce and represent an inclusive learning opportunity, promoting student engagement.

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

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

Clinical Value of Virtual Reality versus 3D Printing in Congenital Heart Disease

Both three-dimensional (3D) printing and virtual reality (VR) are reported as being superior to the current visualization techniques in conveying more comprehensive visualization of congenital heart disease (CHD). However, little is known in terms of their clinical value in diagnostic assessment, medical education, and preoperative planning of CHD. This cross-sectional study aims to address these by involving 35 medical practitioners to subjectively evaluate VR visualization of four selected CHD cases in comparison with the corresponding 3D printed heart models (3DPHM). Six questionnaires were excluded due to incomplete sections, hence a total of 29 records were included for the analysis. The results showed both VR and 3D printed heart models were comparable in terms of the degree of realism. VR was perceived as more useful in medical education and preoperative planning compared to 3D printed heart models, although there was no significant difference in the ratings (p = 0.54 and 0.35, respectively). Twenty-one participants (72%) indicated both the VR and 3DPHM provided additional benefits compared to the conventional medical imaging visualizations. This study concludes the similar clinical value of both VR and 3DPHM in CHD, although further research is needed to involve more cardiac specialists for their views on the usefulness of these tools.

The use of 3D printing for osteopathic medical education of rib disorders

Context

With the advent of increasingly accessible three-dimensional (3D) printing, the possibility to efficiently design and generate prototype innovations is also increasing. This type of manufacturing can potentially enhance medical education by allowing design of models specific to osteopathic manipulative medicine (OMM).

Objectives

To determine the viability of a 3D-printed mechanically moveable rib cage in enhancing the teaching of rib osteopathic principles.

Methods

A single-blind, qualitative study was conducted to evaluate the use of educating students with this novel 3D-printed, movable rib model vs. a traditional static rib model. A total of 237 first-year medical students participated in the study and received the same standardized lecture on the rib dysfunction. Students were also assigned at random to either a comparison group, which would utilize the 3D printed rib model, or the control group, which would utilize the traditional static model. Students would also complete an entrance and exit surveys assessing subjective scores of overall student satisfaction and objective scores for knowledge of OMM rib dysfunction and treatment. An independent samples t-test was applied to assess potential differences between select student evaluation scores (those with continuous variables) of the rib model in the comparison and experiment groups. Chi-square goodness of fit test was conducted to determine if there were any significant differences in entry and exit survey responses between the two groups. Descriptive statistics of the mean and standard deviation were also reported.

Results

For both comparison and control groups, the mean score on an 11-point scale for the evaluation question, "Please rank on a scale of 0-10 how helpful you thought the rib models were to your education," was 9.08 (SD, 1.397). Independent t-test results showed that the comparison group had higher scores than the control group when queried about whether they felt the model accurately depicted the material presented (comparison group mean, 9.55 [SD, 978] vs. control group mean, 9.06 [SD, 1.33; t(235) = 3.253; p=0.01). Chi-square test of goodness-of-fit showed that the differences between the number of correct answers chosen by participants for Item 3 (a case-based question asking students which rib they would treat for a patient presenting to an OMT clinic) was statistically significantly higher for the comparison group (51.9% correct in comparison group vs. 48.1% in control group), even though both groups scored similarly on this item during the entry survey.

Conclusions

The results of this study suggest that utilizing 3D printing to demonstrate somatic dysfunctions of the rib cage may improve understanding and student satisfaction for diagnosis and treatment.

Quality Control in 3D Printing: Accuracy Analysis of 3D-Printed Models of Patient-Specific Anatomy

As comparative data on the precision of 3D-printed anatomical models are sparse, the aim of this study was to evaluate the accuracy of 3D-printed models of vascular anatomy generated by two commonly used printing technologies. Thirty-five 3D models of large (aortic, wall thickness of 2 mm, n = 30) and small (coronary, wall thickness of 1.25 mm, n = 5) vessels printed with fused deposition modeling (FDM) (rigid, n = 20) and PolyJet (flexible, n = 15) technology were subjected to high-resolution CT scans. From the resulting DICOM (Digital Imaging and Communications in Medicine) dataset, an STL file was generated and wall thickness as well as surface congruency were compared with the original STL file using dedicated 3D engineering software. The mean wall thickness for the large-scale aortic models was 2.11 µm (+5%), and 1.26 µm (+0.8%) for the coronary models, resulting in an overall mean wall thickness of +5% for all 35 3D models when compared to the original STL file. The mean surface deviation was found to be +120 µm for all models, with +100 µm for the aortic and +180 µm for the coronary 3D models, respectively. Both printing technologies were found to conform with the currently set standards of accuracy (<1 mm), demonstrating that accurate 3D models of large and small vessel anatomy can be generated by both FDM and PolyJet printing technology using rigid and flexible polymers.

Quantitative Assessment of 3D Printed Model Accuracy in Delineating Congenital Heart Disease

Background: Three-dimensional (3D) printing is promising in medical applications, especially presurgical planning and the simulation of congenital heart disease (CHD). Thus, it is clinically important to generate highly accurate 3D-printed models in replicating cardiac anatomy and defects. The present study aimed to investigate the accuracy of the 3D-printed CHD model by comparing them with computed tomography (CT) images and standard tessellation language (STL) files. Methods: Three models were printed, comprising different CHD pathologies, including the tetralogy of Fallot (ToF), ventricular septal defect (VSD) and double-outlet right-ventricle (DORV). The ten anatomical locations were measured in each comparison. Pearson’s correlation coefficient, Bland–Altman analysis and intra-class correlation coefficient (ICC) determined the model accuracy. Results: All measurements with three printed models showed a strong correlation (r = 0.99) and excellent reliability (ICC = 0.97) when compared to original CT images, CT images of the 3D-printed models, STL files and 3D-printed CHD models. Conclusion: This study demonstrated the high accuracy of 3D-printed heart models with excellent correlation and reliability when compared to multiple source data. Further investigation into 3D printing in CHD should focus on the clinical value and the benefits to patients.

Clinical Applications of Patient-Specific 3D Printed Models in Cardiovascular Disease: Current Status and Future Directions

Three-dimensional (3D) printing has been increasingly used in medicine with applications in many different fields ranging from orthopaedics and tumours to cardiovascular disease. Realistic 3D models can be printed with different materials to replicate anatomical structures and pathologies with high accuracy. 3D printed models generated from medical imaging data acquired with computed tomography, magnetic resonance imaging or ultrasound augment the understanding of complex anatomy and pathology, assist preoperative planning and simulate surgical or interventional procedures to achieve precision medicine for improvement of treatment outcomes, train young or junior doctors to gain their confidence in patient management and provide medical education to medical students or healthcare professionals as an effective training tool. This article provides an overview of patient-specific 3D printed models with a focus on the applications in cardiovascular disease including: 3D printed models in congenital heart disease, coronary artery disease, pulmonary embolism, aortic aneurysm and aortic dissection, and aortic valvular disease. Clinical value of the patient-specific 3D printed models in these areas is presented based on the current literature, while limitations and future research in 3D printing including bioprinting of cardiovascular disease are highlighted.

Three-Dimensional Congenital Heart Models Created With Free Software and a Desktop Printer: Assessment of Accuracy, Technical Aspects, and Clinical Use

BACKGROUND

Three-dimensional printing is increasingly recognized as a valuable tool for congenital heart disease (CHD) procedural planning and education. Cost and complexity currently limit the more widespread adoption of this technology. We sought to demonstrate the accuracy of 3D printed CHD models created from contrast-enhanced magnetic resonance imaging (MRI) and computed tomography (CT) scans using free software and an inexpensive desktop fused filament fabrication (FFF) printer.

METHODS

Solid segmentations of the intracardiac blood pool were created with the program ITK-SNAP. Using the computer program Meshmixer, the segmentation model was hollowed to create a 0.8 mm shell with the inner surface representing endocardium. Three-dimensional models were created on an FFF printer. Four arteries and a ventricular septal defect (VSD) were 3D printed and measured for accuracy. Five models were used to assess candidacy for biventricular surgical repair and one to guide an interventional catheterization.

RESULTS

All six patients underwent intervention planned with the 3D models. The computer model shell walls all achieved specifications within 0.05 mm of the designated 0.8 mm thickness and the original solid blood pool segmentation fit within the hollowed 3D model. The 3D printed arteries and VSD all measured accurately to within 0.5 mm of their source computer model.

CONCLUSION

Accurate 3D printed models of complex, pediatric CHD may be created from volumetric MRI and CT studies using free online software and printed on an inexpensive desktop printer.

Three-dimensional printing for cardiovascular diseases: from anatomical modeling to dynamic functionality

Three-dimensional (3D) printing is widely used in medicine. Most research remains focused on forming rigid anatomical models, but moving from static models to dynamic functionality could greatly aid preoperative surgical planning. This work reviews literature on dynamic 3D heart models made of flexible materials for use with a mock circulatory system. Such models allow simulation of surgical procedures under mock physiological conditions, and are; therefore, potentially very useful to clinical practice. For example, anatomical models of mitral regurgitation could provide a better display of lesion area, while dynamic 3D models could further simulate in vitro hemodynamics. Dynamic 3D models could also be used in setting standards for certain parameters for function evaluation, such as flow reserve fraction in coronary heart disease. As a bridge between medical image and clinical aid, 3D printing is now gradually changing the traditional pattern of diagnosis and treatment.