| 摘要 |
<p>A method of quantitatively determining a contraction to expansion ratio of cardiac muscles in a tangential direction along the surface of the heart from an electrocardiogram-synchronized SPECT image or PET image. The method uses a radioactive chemical built up on the cardiac muscles, by projecting a radioactive chemical built-up quantity (count) on cardiac muscles obtained from a minor axis tomogram reconstructed from the electrocardiogram-synchronized transverse tomogram on to a cylindrical screen having the same axis as that of the major axis of the heart. The projected temporal and spatial changes of the count distribution are expressed by a quadratic second-order partial differential equation describing a fluid. This equation is numerically solved by using a computer. The result obtained is inversely projected on the cardiac muscles to determine tangential displacement of a cardiac muscle at each point of the heart, and a contraction rate and an expansion rate of the cardiac muscles are quantitatively determined as the differences between displacement quantities at individual portions.</p> |
