Share Email Print

Proceedings Paper

Image quality and dose optimization using novel x-ray source filters tailored to patient size
Author(s): Thomas L. Toth; Erdogan Cesmeli; Aziz Ikhlef; Tetsuya Horiuchi
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The expanding set of CT clinical applications demands increased attention to obtaining the maximum image quality at the lowest possible dose. Pre-patient beam shaping filters provide an effective means to improve dose utilization. In this paper we develop and apply characterization methods that lead to a set of filters appropriately matched to the patient. We developed computer models to estimate image noise and a patient size adjusted CTDI dose. The noise model is based on polychromatic X-ray calculations. The dose model is empirically derived by fitting CTDI style dose measurements for a demographically representative set of phantom sizes and shapes with various beam shaping filters. The models were validated and used to determine the optimum IQ vs dose for a range of patient sizes. The models clearly show that an optimum beam shaping filter exists as a function of object diameter. Based on noise and dose alone, overall dose efficiency advantages of 50% were obtained by matching the filter shape to the size of the object. A set of patient matching filters are used in the GE LightSpeed VCT and Pro32 to provide a practical solution for optimum image quality at the lowest possible dose over the range of patient sizes and clinical applications. Moreover, these filters mark the beginning of personalized medicine where CT scanner image quality and radiation dose utilization is truly individualized and optimized to the patient being scanned.

Paper Details

Date Published: 20 April 2005
PDF: 9 pages
Proc. SPIE 5745, Medical Imaging 2005: Physics of Medical Imaging, (20 April 2005); doi: 10.1117/12.595465
Show Author Affiliations
Thomas L. Toth, GE Healthcare (United States)
Erdogan Cesmeli, GE Healthcare (United States)
Aziz Ikhlef, GE Healthcare (United States)
Tetsuya Horiuchi, GE Healthcare (United States)

Published in SPIE Proceedings Vol. 5745:
Medical Imaging 2005: Physics of Medical Imaging
Michael J. Flynn, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?