Table of Contents
International Journal of Molecular Imaging
Volume 2011, Article ID 197381, 8 pages
http://dx.doi.org/10.1155/2011/197381
Research Article

Quantitative Accuracy of Low-Count SPECT Imaging in Phantom and In Vivo Mouse Studies

Centre for Molecular Oncology and Imaging, Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, UK

Received 1 September 2010; Revised 12 December 2010; Accepted 19 January 2011

Academic Editor: Habib Zaidi

Copyright © 2011 Ciara M. Finucane et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We investigated the accuracy of a single photon emission computed tomography (SPECT) system in quantifying a wide range of radioactivity concentrations using different scan times in both phantom and animal models. A phantom containing various amounts of In-111 or Tc-99m was imaged until the activity had decayed close to background levels. Scans were acquired for different durations, employing different collimator pinhole sizes. VOI analysis was performed to quantify uptake in the images and the values compared to the true activity. The phantom results were then validated in tumour-bearing mice. The use of an appropriate calibration phantom and disabling of a background subtraction feature meant that absolute errors were within 12% of the true activity. Furthermore, a comparison of in vivo imaging and biodistribution studies in mice showed a correlation of 0.99 for activities over the 200 kBq to 5 MBq range. We conclude that the quantitative information provided by the NanoSPECT camera is accurate and allows replacement of dissection studies for assessment of radiotracer biodistribution in mouse models.