Development and validation of real-time simulation of X-ray imaging with respiratory motion

Abstract

soft tissue modelling and ray tracing on GPU to simultaneously compute the respiratory motion and X-ray imaging in real-time. Our aim is to provide validated building blocks with high fidelity to closely match both the human physiology and the physics of X-rays. A CPU-based set of algorithms is presented to model organ behaviours during respiration. Soft tissue deformation is computed with an extension of the Chain Mail method. Rigid elements move according to kinematic laws. A GPU-based surface rendering method is proposed to compute the X-ray image using the Beer-Lambert law. It is provided as an open-source library. A quantitative validation study is provided to objectively assess the accuracy of both components: i) the respiration against anatomical data, and ii) the X-ray against the Beer-Lambert law and the results of Monte Carlo simulations. Our implementation can be used in various applications, such as interactive medical virtual environment to train percutaneous transhepatic cholangiography in interventional radiology, 2D/3D registration, computation of digitally reconstructed radiograph, simulation of 4D sinograms to test tomography reconstruction tools.}, pmid = {to appear}, publisher = {Elsevier} } AbstractWe present a framework that combines evolutionary optimisation, soft tissue modelling and ray tracing on GPU to simultaneously compute the respiratory motion and X-ray imaging in real-time. Our aim is to provide validated building blocks with high fidelity to closely match both the human physiology and the physics of X-rays. A CPU-based set of algorithms is presented to model organ behaviours during respiration. Soft tissue deformation is computed with an extension of the Chain Mail method. Rigid elements move according to kinematic laws. A GPU-based surface rendering method is proposed to compute the X-ray image using the Beer-Lambert law. It is provided as an open-source library. A quantitative validation study is provided to objectively assess the accuracy of both components: i) the respiration against anatomical data, and ii) the X-ray against the Beer-Lambert law and the results of Monte Carlo simulations. Our implementation can be used in various applications, such as interactive medical virtual environment to train percutaneous transhepatic cholangiography in interventional radiology, 2D/3D registration, computation of digitally reconstructed radiographs, simulation of 4D sinograms to test tomography reconstruction tools.

Interactive teaching environment for diagnostic radiography with real-time X-ray simulation and patient positioning

“…Hounsfield units are then converted into their respective chemical compositions and densities [24]. A quantitative validation study has been conducted to assess the accuracy of the simulated X-ray images [22].…”

“…It has been ported to modern graphics processing unit (GPU) using OpenGL [21], providing a real-time X-ray image simulation tool. It is now available as an Open-Source project, gVirtualXRay [22]. 1 This research proposes an X-ray projectional radiograph simulator to teach and train the procedure in a safe environment.…”

Densitometric Radiographic Imaging With Contour Sensors

“…This process requires just one X-ray image from the patient (which in turn involves a lower dose). The X figure is computed with the same ray-tracing basis [49] included in the open source library gVirtualXRay presented in [61], and the same methods tackled in Section V. Attenuation is then derived with:…”

Use of fast realistic simulations on GPU to extract CAD models from microtomographic data in the presence of strong CT artefacts

“…This high fidelity model is, however, very slow. A week may be needed to produce an image without too much noise [33]. Parallelism and variance reduction techniques may be deployed to speed up Monte Carlo simulations, however real-time performance is still not achievable, particularly on desktop computers.…”

“…We have developed and validated an open source library (gVirtualXRay) to perform the attenuation calculations on GPU using OpenGL [29,32,33]. gVirtualXRay is written in C++ and GLSL.…”