Effects of piecewise smoothing on cardiac SPECT reconstruction

In this work we investigate the use of total variation (TV) regularization in the context of single photon emission computed tomography (SPECT), which is currently widely used for detection and evaluation of coronary artery diseases. Owing to its piecewise smoothing property, TV regularization is known to preserve discontinuities in the resulting images in inverse problems. Our goal is to study whether such a property will be useful for improving the reconstruction accuracy of perfusion defects in cardiac SPECT, which is an important clinical task. In our evaluation study we simulated cardiac gated SPECT imaging with Tc-99m labeled sestamibi. Our results demonstrate that, compared with a traditional quadratic regularization approach, use of TV regularization could lead to improved accuracy of perfect defect detection even when perfection defects are subtle.