The NIH/NIGMS
Center for Integrative Biomedical Computing

The simulation of bioelectric fields, and estimation of their parameters from measurements, have always been a core research domain for CIBC, and we continue to pursue exciting new topics in our Simulation & Estimation TR&D. We also continue to create and support a complete and comprehensive set of software tools for relevant image-based modeling, simulation, and estimation. While the simulation and estimation aspects focus on electricity in the setting of biomedical problems, they span a broad range of fields that includes both intrinsic electric currents flowing from organs in the body and the application of external currents to simulate or modulate function in the heart and brain. Software integration is a major technical theme of the Simulation & Estimation TR&D as we continue to explore efficient means to interact with third party programs and libraries at that same time that we develop our own tools for many aspects of this domain in which we have the expertise and experience. Our goal is to provide a useful and flexible framework into which many new and existing components can interact and provide our DBP partners and collaborators with a rich environment for their biomedical and technical research.

Just as interactions with DBPs and collaborations drive the simulation research and development and provide it with valuable test beds, the synergy within the CIBC is also essential to success. Simulation is perhaps the most dependent beneficiary of the creation of image based segmentation and mesh generation tools, of the visualization capabilities necessary to view all aspects of the simulation studies, and of the mature infrastructure that integrates and supports the simulation software components. Within the Center, the simulation applications also serve as internal drivers and test beds for all the other tools, a microcosm of the larger collaborative environment in which we have a large, and growing, impact.

The figure below is an excellent example of our integrative approach: research emerging from the synergy of two DBP partners, Drs. Trayanova and Plank and Dr. Marrouche that resulted in a publication and a cover figure in a leading journal in cardiac electrophysiology. The model generation, visualization, and exploration of the simulation results were all made possible by CIBC software and the simulation was constructed by interfacing with the CARP software tools developed by Dr. Plank and used extensively in our collaborations with Dr. Trayanova. The target application of these simulations was motivated by Dr. Marrouche and his colleagues, who interpret the morphology and timing of signals recorded with a bipolar catheter in the chambers of the heart. Despite considerable clinical experience, they have only incomplete understanding of the effects of catheter orientation and location so that findings from simulations like this can provide necessary insights to improve diagnostic determinations.

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Example of the application of integrated software in an interdisciplinary collaboration. This figure contains schematic diagrams of a slab of cardiac tissue (upper panel) through which activation waves are simulated using the CARP software and color coded in a visualization using SCIRun. The lower panel shows the bipolar cardiac catheter with which we sampled the surface and volume above the slab, with some of the resulting electrogram signals shown in the lower, right hand panel.