Interest has been shown in cardiac strain for its role in feedback information to the brain. The feedback information on the heart's condition is measured in the body using biological "strain gauges" known as baroreceptors. Doctor Cameron Bennett of the Royal Brisbane Hospital put forward a hypothesis in 1994 as to the stimulus-response mechanism between the brain and the heart, requiring heart wall strain (in particular the left ventricle) to be quantitatively measured. Until recently, no useful methods existed to collect data on strain within the heart wall in vivo. Practical, non invasive methods have only arisen from use of magnetic resonance imaging technology (MRI).

A system for measuring the strain within the walls of the left ventricle is being developed with collaboration between Cardiac scientists at the Royal Brisbane Hospital, the Centre for Magnetic Resonance and the Department of Mechanical Engineering. Data is collected using "tagged" images of the heart at the Magnetic Resonance Centre and the relevant information is processed at the Royal Brisbane Hospital. The scope of this thesis is to provide the final stage of data processing to obtain values of wall strain within the heart using finite element methods.

This seminar will describe the data collection processes, and the numerical algorithms which have been developed to convert the raw data into information readily processed by a commercial finite element program. In particular, the difficulties posed by extracting data from two-dimensional images to gain information on three-dimensional heart wall motion will be discussed. A description of the anticipated results of the project will also be presented.