Dynamic simulation of cardiac ultrasound based on ray tracing and ultrasound Doppler technology

The dynamic simulation of cardiac ultrasound is a crucial and challenging task. In this paper, a three-dimensional cardiac animation model is reconstructed with computed tomography(CT) data. Ray tracing and ultrasound Doppler techniques are employed for the computational simulation of cardiac motion. Subsequently, the animation sequences are cached on the graphics processing unit(GPU) to achieve real-time dynamic simulation of cardiac ultrasound. The experimental results show that with 512 rays and an ultrasound image resolution of 145 μm, the model, which consists of over 200,000 triangular facets, is able to generate dynamic ultrasound images at a rate exceeding 20 frames per second. Meanwhile, ultrasound Doppler simulation is realized through the ray tracing method, which verifis the feasibility of using scatterer contribution to achieve ultrasound Doppler simulation.

心脏超声动态仿真属于一项兼具重要研究意义与挑战性的课题。本文基于计算机断层扫描（computed tomography, CT）数据重建了三维心脏动画模型。本研究采用光线追踪（ray tracing）与超声多普勒（ultrasound Doppler）技术实现心脏运动的计算仿真。随后将动画序列缓存于图形处理器（graphics processing unit, GPU）中，以此实现心脏超声的实时动态仿真。实验结果表明，当采用512条光线、超声图像分辨率达145 μm时，该由超20万个三角面片构成的模型可实现每秒20帧以上的动态超声图像生成速率。与此同时，本研究通过光线追踪方法实现了超声多普勒仿真，验证了利用散射体贡献度完成超声多普勒仿真的可行性。