Cart (Loading....) | Create Account
Close category search window
 

Geometric co-calibration of a small animal SPECT-CT system with fully superimposed fields-of-view

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Liji Cao ; German Cancer Research Center (DKFZ), Div. Medical Physics in Radiation, Im Neuenheimer Feld 280, Heidelberg, D-69120, Germany ; Kriesche, T. ; Peter, J.

In this paper we present a method for geometric co-calibration of a single-gantry SPECT-CT small animal imaging system with axially overlapping fields-of-view. Because spatial resolution and noise level differ greatly between both sub-systems the method incorporates different strategies to obtain more accurate calibration values. Firstly, x-ray tomographic calibration is performed on a steel-sphere-phantom which includes 13 steel spheres with 1 mm in diameter, placed on a straight line. Geometric displacement for the high-resolution x-ray CT system (five parameters) is then calculated based on a mathematical analysis of those projection data. Secondly, a 360 degree SPECT-CT imaging of point sources, which are labeled with both radioactivity and x-ray absorber, is applied. With the calculated geometric parameters for the CT system the exact positions of the point sources in the CT volume can be extracted from the CT reconstruction result, and given the positional information in CT as a priori the geometric displacement for the SPECT camera as well as the intrinsic co-alignment between the SPECT and the CT sub-systems (six parameters) is estimated with an iterative optimization strategy (Levenberg-Marquardt). For routine imaging, the calibrated parameters are incorporated into the image reconstruction algorithms applied to the SPECT (MLEM) and CT (FDK) data, respectively, without an additional registration process. Our results show intrinsically aligned images of both modalities with high spatial resolution and low level of mis-alignment. This method is feasible for multi-modality imaging systems with common fields-of-view, however, large difference in spatial resolution and noise level.

Published in:

Nuclear Science Symposium Conference Record, 2008. NSS '08. IEEE

Date of Conference:

19-25 Oct. 2008

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.