Segmental reconstruction of myocardial perfusion from biplane angiographic projections by regularized iterative matrix inversion

The proposed segmental reconstruction technique allows the assessment of the relative mass density levels (segment values) in eight segments of slices through the myocardial muscle from biplane X-ray angiographic projections, and has been adopted from an approach by D.G.W. Onnasch et al. (1986). From a simple projection model, a set of eight dependent equations can be derived. This set is solved by regularized iterative matrix inversion that minimizes least square errors under imposed constraints. The projection images and a reconstructed slice are illustrated. The definition of the segments, intervals at projection data, and the related projection matrix are defined and the iterative regularized matrix inversion is described. Experiments with computer simulations have shown that differences between segment values of actual and reconstructed slices were less than -45% of maximum (normal) segment values