Fang-Cheng Yeh1, Yijen L. Wu2, Qing Ye2, T. Kevin Hitchens2, Chien Ho2
1Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States; 2Pittsburgh NMR Center for Biomedical Research, Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA
A new imaging modality called R2*-m imaging is proposed to detect ultra-small superparamagnetic iron oxide (USPIO) nanoparticle-labeled cells in rat cardiac tissue modeling acute allograft rejection. By introducing an additional spin density term, R2*-m imaging is shown to provide a higher specificity than regular R2* image in term of their vunerabilibity to the suscupetibility artifact occurred in the air-tissue junctions. The resulting images demonstrate a clearer image background, with the existence of iron particles presented in high intensity, which offers a more specific identification of the rejection site. The specificity feature of R2*-m Imaging may provide a better quantification analysis on the severity of the rejection.