Share Email Print
cover

Proceedings Paper

Field-of-view-dependent helical pitch in multislice CT
Author(s): Michael D. Silver; Katsuyuki Taguchi; Kyung S. Han
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

A goal of multi-scale CT (MSCT) is to decrease the scan time needed to image a volume of the patient. Detectors with multiple rows of sensors enable higher helical pitches and thus shorter scan times. One of the difficulties in devising an efficient reconstruction method with good image quality and good dose utilization is that each image pixel is irradiated by the cone-beam for a different range of gantry orientations. We derive a new half-scan weighting scheme for a helical, cone-beam backprojection algorithm based on the virtual fan angle. The virtual fan angle, in turn, determines the gantry view range such that image quality is maintained by allowing only valid ray-sums while using the available dose. This restricts the virtual fan angle to be at least the true geometric fan angle but less than 180 degree(s). The result is a computational efficient and dose efficient reconstruction algorithm with a continuous range of field-of-view dependent helical pitches. A 43% higher helical pitch is possible for the smallest field-of-view compared with the largest field-of-view, using the parameters of a commercial MSCT-scanner. Dose efficiency is compared among the new method and standard half scan and full scan approaches.

Paper Details

Date Published: 28 June 2001
PDF: 12 pages
Proc. SPIE 4320, Medical Imaging 2001: Physics of Medical Imaging, (28 June 2001); doi: 10.1117/12.430862
Show Author Affiliations
Michael D. Silver, Bio-Imaging Research, Inc. (United States)
Katsuyuki Taguchi, Toshiba Corp. (Japan)
Kyung S. Han, Bio-Imaging Research, Inc. (United States)


Published in SPIE Proceedings Vol. 4320:
Medical Imaging 2001: Physics of Medical Imaging
Larry E. Antonuk; Martin Joel Yaffe, Editor(s)

© SPIE. Terms of Use
Back to Top