James W. Hugg1, Benjamin M. W. Tsui2,
Orhan Nalcioglu3, Dirk Meier4, Mark J. Hamamura3,
Douglas J. Wagenaar1, Bradley E. Patt1
1Gamma Medica, Northridge,
CA, United States; 2Johns Hopkins University, Baltimore, MD,
United States; 3University of California, Irvine, CA, United
States; 4Gamma Medica, Oslo, Norway
We have built and tested three SPECT prototypes that can be inserted into small-animal or whole-body MRI systems for simultaneous, dynamic imaging of mice and rats. We have measured and characterized the Hall Effect due to the Lorentz force in the MR-compatible CZT gamma photon detectors. Otherwise, the MR and SPECT systems do not significantly affect each other. We have demonstrated simultaneous, dynamic SPECT-MR imaging in mice. We are developing MR attenuation and scatter corrections and MR priors for quantitative SPECT reconstruction. Imaging a SPECT agent can provide a molecular imaging contrast for MR images at pico- to nano-molar sensitivities.