A VR simulator provides low-cost, realistic training for intracardiac techniques for determining the heart's mechanical and electrical activities. A geometric method models interaction between a catheter and the heart wall. Boundary-enhanced voxelization accelerates detection of catheter-heart interaction. A tactile interface incorporates a VR catheter unit to track the catheter's movement.

No abstract

<p>Much efforts have been made to develop realistic cardiac models for clinical and research purposes. However, to implement these models always needs to handle excessive computational loads due to the complex and dynamic natures of the heart given limited computational power of Central Processing Unit (CPU). In this paper, a real-time approach to cardiac modeling is proposed based on the Graphics Processing Unit (GPU). A hardware platform is first designed and tested with a simplified model to represent the cardiac activities. Motion of mesh-based heart is then approximated to simulate the movement of each vertex. Time functions are used within the GPU platform to describe the cardiac cycle. The parallel computing feature of GPU platform significantly speeds up the computation process in real-time with over 140,000 vertices motion based on the time functions. The program is developed on top of CUDA architecture proposed and developed by nVIDIA. Computational Experiments show visualization of the cardiac dynamics is significantly benefiting from this new solution. Further improvement of the GPU based cardiac simulation is discussed.</p>

A novel B-Spline based approach to phase unwrapping in tagged magnetic resonance images is proposed for cardiac motion tracking. A bicubic B-spline surface is used to model the absolute phase. The phase unwrapping problem is formulated as a mixed integer optimization problem that minimizes the sum of the difference between the spatial gradients of absolute and wrapped phases, and the difference between the rewrapped and wrapped phases. In contrast to the existing techniques for motion tracking, the proposed approach can overcome the limitation of interframe half-tag displacement and increase the robustness of motion tracking. The article further presents a hybrid harmonic phase imaging-B-spline method to take the advantage of the harmonic phase imaging method for small motion and the efficiency of the B-Spline approach for large motion. The proposed approach has been successively applied to a full set of cardiac MRI scans in both long and short axis slices with superior performance when compared with the harmonic phase imaging and quality guided path-following methods.

No abstract