Evaluating rotating slant-hole SPECT with respect to parallel hole SPECT

The objective of this project was to comparatively evaluate the image quality of rotating slant-hole (RSH) SPECT versus parallel beam SPECT. RSH collimators provide a means for increasing SPECT sensitivity at a volume of interest (VOI), such as the breast or heart. However RSH has an asymmetric geometric response function (GRF) and requires fully-3D reconstruction. A series of phantom simulations were performed to study overall image quality in terms of contrast, resolution, and noise. A cardiac phantom experiment was also performed to evaluate myocardial uniformity and to make an overall assessment of visual image quality. Simulation results demonstrated very similar contrast and resolution for RSH and parallel beam reconstructed images when compensations were made for attenuation and detector response. For the same acquisition time, the normalized standard deviation of the VOI in the reconstructed images of a uniform phantom was found to be 1.31 times higher for parallel beam than for RSH. The reconstructed cardiac phantoms using RSH were and found to give improved results compared to parallel hole SPECT. These results show that the increased detection; efficiency and improved noise properties of RSH can make it a good choice for cardiac imaging