Inverse problems in biomechanics

The FEM (Finite Element Method) is a powerful numerical technique in solving boundary value problems in Biomechanics, which are difficult to analyze by other closed form or numerical procedures due to their complexity and irregularity in shape, size and forces applied. We define the inverse problem as one where the distribution of the material property of a structure is obtained given the original and the deformed geometrical shape and the loading pattern. In this paper, an example of an inverse FEM technique has been used to analyze the diastolic tissue elastic stiffness ('E'-value) of the left ventricle. The concept of an index for normal left ventricle based on 'E'-values has been introduced so that the ischemic tissue can be identified from the normal ones based on their 'E'. The study is based on the angiographic images of left ventricle which are further corrected for both magnification and pin-cushion distortion effects for accurate determination of regional 'E'-values.