3-dimensional printing for the diagnosis of left ventricular outflow tract obstruction after mitral valve replacement.

The objective of this study was to evaluate the use of the generation of 3D models and 3D prints of complex cases for physicians at the example of an intricate left ventricular outflow tract obstruction (LVOTO). LVOTO is a known complication of mitral valve surgery. A 38-year-old female patient with increasing dyspnoea after mitral valve replacement was referred to our centre. Echocardiography showed a strut of the bioprosthetic heart valve protruding into the left ventricular outflow tract. However, the diagnosis of a LVOTO was difficult based on echocardiography alone. Therefore, we fabricated a physical model of the left ventricular outflow tract, the mitral valve, the aortic valve and the left ventricle. With this physical model in hand, we were able to visualize the LVOTO and to discuss potential therapeutic options. Moreover, we were able to plan the subsequent redo surgery in detail using the model. This case shows the benefit of 3D printing technologies for surgeons and patients, not only for analysis, but also during the decision-making and pre-operative planning process.

Virtual Reality Analysis of Three-Dimensional Echocardiographic and Cardiac Computed Tomographic Data Sets.

BACKGROUND: Three-dimensional echocardiographic (3DE) imaging and cardiac computed tomographic (CCT) imaging are important cardiac imaging tools. Despite the three-dimensional nature of these image acquisitions and reconstructions, they are visualized on two-dimensional monitors with shading and coloring to create the illusion of three dimensions. Virtual reality (VR) is a novel tool that allows true three-dimensional visualization and manipulation. The aims of this study were to test the feasibility of converting 3DE and CCT data into three-dimensional VR models, compare the variability of measurements performed in VR and conventional software, assess the diagnostic quality of VR models, and understand the value of VR over conventional viewing. METHODS: Custom software with clinically relevant postprocessing tools (interactively adjustable visualization parameters, multiplanar reconstructions, cropping planes, and nonplanar measurements) was developed to convert 3DE and CCT data into VR models. Anatomic measurements of 15 3DE and 15 CCT data sets of the mitral valve were compared using conventional software and in the VR environment. Additionally, the diagnostic quality of the VR models created from 3DE and CCT data sets was assessed. RESULTS: The 3DE and CCT data sets were successfully converted into VR models in <3 min. The measurement variabilities were reduced by 40% (20.1% vs 12.2%) for 3DE imaging and 34% (15.3% vs 10.1%) for CCT imaging by using VR. The mean time needed for measurements was reduced by 31% (from 61 to 42 sec) for 3DE imaging and 39% (from 37 to 23 sec) for CCT imaging. Most users reported facile manipulation of VR models, diagnostic quality visualization of the anatomy, and high confidence in the measurements. CONCLUSIONS: This study demonstrates the feasibility of converting 3DE and CCT data into diagnostic-quality VR models. Compared with conventional imaging, VR analysis is associated with faster navigation and accurate measurements with lower variability.

Three-dimensional echo for the assessment of valvular heart disease.

Three-dimensional echocardiography (3DE) is a valuable tool to be used in addition to and not instead of two-dimensional echocardiography by providing complementary information and improved quantitative accuracy and reproducibility compared with two-dimensional techniques. 3DE has the potential to become the standard echocardiographic examination procedure for the assessment of valvular disease. This article describes applications of 3DE.

Three-Dimensional Echocardiography: The Gateway to Virtual Reality!

Virtual reality (VR) is one of the latest developments in cardiac three-dimensional (3-D) ultrasound. A VR heart model linked to 3-D echocardiographic image datasets provides the observers spatial information regarding a 3-D image dataset and prevents the "lost in space effect" in difficult and relevant coupled diseases when integrated into 3-D reconstruction software. Standardized echocardiographic views can be selected within the integrated developed VR heart model, and this is the first step to automatic 3-D computations with minimal operator interaction. VR heart models open exciting opportunities in the field of teaching echocardiographic cardiology, diagnosis, and examinable states.

Volumetric Holography of Cardiac Defects in Humans: Initial Clinical Experience Using Tomographic Echocardiographic Data.

We have previously described a method to develop holograms that does not entail the presence of laser light source in the clinical environment. Although we have demonstrated the feasibility of holography from cardiac ultrasound data to depict normal and abnormal cardiac anatomy in experimental studies, the ability of holography from ultrasound data to image structural cardiac anomalies in patients is not known. In this exploratory study, we addressed the question of whether it was possible to image cardiac pathology by holography in patients with mitral valve disease, atrial septal defects, and ventricular aneurysms. Parallel, tomographic echocardiographic data obtained during transesophageal echocardiography were used to generate holograms of cardiac disorders. Holographic three-dimensional (3-D) reproduction contains up to 1024 by 1024 pixels and full gray scale in each of the individual slices. Holograms of cardiac defects depicted their true spatial location, which not only enhanced the anatomic appreciation of the defect itself, but also revealed the depth and the relationship of the structures in proximity of the defect. Thus, 3-D imaging of cardiac anomalies by volumetric multiplexed holography is feasible.