π-scheme short-scan SPECT and image reconstruction

Abstract

Because the effects of physical factors such as photon attenuation and spatial resolution are distance-dependent in single-photon emission computed tomography (SPECT), it is generally considered that accurate image reconstruction requires knowledge of the data function over 2/spl pi/. In SPECT with only uniform attenuation, Noo and Wagner (2001) showed that an accurate image can be reconstructed from knowledge of the data function over /spl pi/. In this work, we develop an heuristic perspective to demonstrate - and use simulation studies to confirm - that the data function in /spl pi/-scheme SPECT with non-uniform attenuation contains complete information for an accurate image reconstruction. In its most general form, the proposed /spl pi/-scheme SPECT entails data acquisition over disjoint angular intervals without conjugate views, totalling to /spl pi/ radians, thereby allowing flexibility in choosing projection views at which the emitted gamma-rays may undergo the least attenuation and blurring.