Study of kinetics of 19F-MRI using a fluorinated imaging agent (19FIT) on a 3T clinical MRI system
To use 19F imaging tracer (19FIT-27) to evaluate kinetics in major organs.
Kinetics studies using proton MRI are difficult because of low concentration of 19FIT-27 protons relative to background water protons. Because there is no background source of 19F NMR in a biological body, 19F may be an ideal nucleus to directly trace 19FIT-27. However, there are several challenges for reliable 19F MR imaging and spectroscopy, particularly with clinical whole-body MRI systems, which include low concentrations and long 19F T1.
Methods and materials
We performed a dynamic 19F MRI study on mice at a 3T whole-body MRI system using a homemade transmit/receive (Tx/Rx) switch and a Tx/Rx volume RF coil. We used a newly developed fluorine imaging agent, which has 27 identical fluorine atoms with identical chemical shift, a relatively short T1, and high hydrophilicity. Basic kinetics parameters were estimated from the 19F signal-time curve.
Results and discussions
Resultant fluorine images show fairly high spatial (3 × 3 × 3 mm3) and temporal resolutions. Biodistribution and kinetics of 19FIT-27 are obtained via 19F images for major uptake organs.
Whole-body dynamic 19F MRI of newly developed 19FIT-27 in mice was obtained with fairly high spatial and temporal resolutions on a 3T clinical MRI system. The present study demonstrates the feasibility of 19F MRI using our newly developed compound to investigate major organ kinetics.
Keywords19F MRI Kinetics 19FIT
This work was supported by NSF CBET 1133908.
Conflict of interest
All authors declare that they have no conflict of interest.
The study did not involve any human subject, therefore no ethical standard is required.
No informed consent is required.
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