Abstract #3806

Simultaneous, Dynamic SPECT-MRI Demonstrated in Three Small-Animal Prototypes

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.