Towards in vivo quantitative 19F MRI in the Spleen

Motivation: Perfluorocarbon emulsions can track immune cells activated after myocardial infarction. However, quantitative in vivo 19F MRI in large animals is challenging due to positional changes of organs. Goal(s): Developing a method to obtain comparable 19F signals in pig's spleens on multiple measurements over one week using a non-homogeneous receive coil. Approach: The receive coil was tracked using 19F markers. A region in the spleen with equal position from the coils was chosen for the evaluation. Results: Phantom experiments showed similar signal within the ROI. In vivo, a signal decay was measured for each animal with an average half-life in the spleen of 4.6d. Impact: The presented method allows for quantification of 19F signal decay in non-static large animal organs. While it already works well on its own, it allows for future combination with a sensitivity map in the future.