Research Abstracts Online
January 2009 - March 2010
University of Minnesota Twin Cities
Department of Physical Medicine and Rehabilitation
PI: Robert P. Patterson, Associate Fellow
Modeling of Electric Potentials in Human Thorax
This project investigates various electrical measurements in the body. Three-dimensional models of the human thorax are generated from magnetic resonance images. These images are segmented and all tissues are assigned a corresponding electrical resistivity. Current paths through the body may then be studied by placing electrodes in the thorax model and solving the resulting forward problem. This group’s finite difference models consist of 3.8 million elements. Applications include design of implantable pacemakers and defibrillator electrode systems, impedance cardiography, body fluid and fat measurement, and electrical impedance tomography.
Current research is focused on measuring pulmonary edema using both internal pacemaker leads and external electrodes. Recently added work includes the effects of pulmonary edema on defibrillation thresholds. It will focus on user-friendly electrode positions for impedance measurements used in detecting pulmonary edema associated with heart failure and cardiac dynamics. The cardiac-dynamics application will help in better understanding the homodynamics occurring with cardiac rhythm problems. The researchers’ earlier work on defibrillation current density patterns in the heart based on lead locations and possible tissue damage is in the process of being published.
Andres Belalcazar, Visiting Researcher
Fei Yang, Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri