Yibin Xie1, Steven M. Shea2,
Yingli Fu3, Wesley D. Gilson2, Tina Ehtiati2,
Ronald Ouwerkerk4, Dorota Kedziorek3, Meiyappan
Solaiyappan3,
1Department of Biomedical Engineering, Johns
Hopkins University, Baltimore, MD, United States; 2Center for
Applied Medical Imaging, Siemens Research Corporate, Inc., Baltimore, MD,
United States; 3Russell H. Morgan Department of Radiology and
Radiological Science, Johns Hopkins University, Baltimore, MD, United States;
4National Institutes of Health, Bethesda, MD, United States
The
delivery and engraftment of therapeutic stem cells can be monitored by both 19F
MRI and c-arm CT using alginate-poly-L-lysine-alginate microcapsules loaded
with perfluorooctylbromide (APA-PFOB). MR tracking is advantageous for high
sensitivity and absence of ionizing radiation. However it suffers from lower
resolution. This study evaluates accuracy of tracking encapsulated
mesenchymal stem cells using 19F MRI relative to c-arm CT. Results
show a high identification and agreement in the spatial locations and volumes
of the injection sites between MRI and CT demonstrating that MRI provides an
accurate alternative to CT for tracking of encapsulated stem cells in vivo.