TY - JOUR T1 - A few planar detectors collimated by multiple pinholes for cardiac SPECT imaging JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 406 LP - 406 VL - 50 IS - supplement 2 AU - Qiu Huang AU - Youngho Seo AU - Jason Bowen AU - Rostyslav Boutchko AU - Grant Gullberg Y1 - 2009/05/01 UR - http://jnm.snmjournals.org/content/50/supplement_2/406.abstract N2 - 406 Objectives The objective of this work was to study the necessary angular sampling for a cardiac SPECT system with stationary planar detectors placed at a few angular positions each collimated by multiple pinholes. Methods A SPECT study was performed using a dual-head GE Infinia Hawkeye SPECT/CT system. Each detector head was mounted with a custom built multipinhole collimator of 9 4.5 mm diameter apertures. Projection data were acquired of an anthropomorphic torso phantom with lung and cardiac insert. The torso was filled with water to simulate soft tissue. A dose of 0.1 μCi of 99mTc was injected into the myocardium. The two heads rotated in H-mode to obtain 24 projections over 360°. These projection data were combined to generate different data sets corresponding to different geometrical angular sampling. For each of the geometries, the ML-EM algorithm with total variation regularization was applied to reconstruct the distribution of 99mTc. The geometric response was modeled in the reconstruction. Results The quality of the reconstructed images varied with the number of views and the angular positions of the multipinhole collimated detectors. Data acquired at just two detector positions resulted in non-uniformity in the apex region of the left ventricle, whereas three heads positioned at equal angular separation from left posterior oblique to right anterior oblique resulted in less artifact and had comparable reconstructed images to the geometry with 24 positions over 2π. Conclusions The phantom study suggested that a stationary SPECT system with a few detector heads collimated by multiple pinholes has the potential to supply good image quality for myocardial perfusion imaging. ER -