Yi Chen1, Yan Xi1, Jun Zhao1. 1. School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
Abstract
BACKGROUND: The temporal resolution of current computed tomography (CT) systems is limited by the rotation speed of their gantries. OBJECTIVE: A helical interlaced source detector array (HISDA) CT, which is a stationary CT system with distributed X-ray sources and detectors, is presented in this paper to overcome the aforementioned limitation and achieve high temporal resolution. METHODS: Projection data can be obtained from different angles in a short time and do not require source, detector, or object motion. Axial coverage speed is increased further by employing a parallel scan scheme. Interpolation is employed to approximate the missing data in the gaps, and then a Katsevich-type reconstruction algorithm is applied to enable an approximate reconstruction. RESULTS: The proposed algorithm suppressed the cone beam and gap-induced artifacts in HISDA CT. The results also suggest that gap-induced artifacts can be reduced by employing a large helical pitch for a fixed gap height. CONCLUSIONS: HISDA CT is a promising 3D dynamic imaging architecture given its good temporal resolution and stationary advantage.
BACKGROUND: The temporal resolution of current computed tomography (CT) systems is limited by the rotation speed of their gantries. OBJECTIVE: A helical interlaced source detector array (HISDA) CT, which is a stationary CT system with distributed X-ray sources and detectors, is presented in this paper to overcome the aforementioned limitation and achieve high temporal resolution. METHODS: Projection data can be obtained from different angles in a short time and do not require source, detector, or object motion. Axial coverage speed is increased further by employing a parallel scan scheme. Interpolation is employed to approximate the missing data in the gaps, and then a Katsevich-type reconstruction algorithm is applied to enable an approximate reconstruction. RESULTS: The proposed algorithm suppressed the cone beam and gap-induced artifacts in HISDA CT. The results also suggest that gap-induced artifacts can be reduced by employing a large helical pitch for a fixed gap height. CONCLUSIONS: HISDA CT is a promising 3D dynamic imaging architecture given its good temporal resolution and stationary advantage.