Article

An inverse-geometry volumetric CT system with a large-area scanned source: A feasibility study

Department of Radiology, Stanford University, Stanford, California 94305, USA.
Medical Physics (Impact Factor: 3.01). 10/2004; 31(9):2623-7. DOI: 10.1118/1.1851913
Source: PubMed

ABSTRACT We propose an inverse-geometry volumetric CT system for acquiring a 15-cm volume in one rotation with negligible cone-beam artifacts. The system uses a large-area scanned source and a smaller detector array. This note describes two feasibility investigations. The first examines data sufficiency in the transverse planes. The second predicts the signal-to-noise ratio (SNR) compared to a conventional scanner. Results showed sufficient sampling of the full volume in less than 0.5 s and, when compared to a conventional scanner operating at 24 kW with a 0.5-s voxel illumination time (e.g., 0.5-s gantry rotation and pitch of one), predicted a relative SNR of 76%.

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