In vivo 19F NMR imaging.

Area of Science:

• Medical Imaging
• Nuclear Magnetic Resonance Spectroscopy
• Fluorine Chemistry

Background:

• 19F NMR spectroscopy offers unique advantages for in vivo imaging due to the absence of a 19F background signal in biological tissues.
• Fluorinated compounds, including anesthetics and perfluorochemicals, are potential contrast agents for 19F NMR imaging.
• Challenges exist in achieving sufficient signal-to-noise ratio and spatial resolution for in vivo 19F NMR imaging.

Purpose of the Study:

• To evaluate the feasibility and potential applications of 19F NMR imaging in vivo using clinically safe fluorinated compounds.
• To assess the ability of 19F NMR chemical shift imaging to differentiate between different fluorinated agents.
• To demonstrate the utility of 19F NMR imaging for visualizing specific organs and functional processes.

Main Methods:

• Acquisition of in vitro and in vivo 19F NMR spectra and images using fluorinated anesthetics and perfluorochemicals (Fluosol-DA).
• Utilized standard and chemical shift imaging techniques to analyze signal origins and spatial distribution.
• Correlated 19F NMR images with conventional proton NMR images to confirm signal localization.

Main Results:

• Chemical shift imaging successfully distinguished between mixtures of halothane and methoxyflurane in vitro.
• In vivo 19F NMR imaging of Fluosol-DA in rats allowed visualization of the liver within 30 minutes, reflecting reticuloendothelial cell activity.
• High-contrast anatomical images of the gastrointestinal tract were obtained in as little as 12 minutes by filling the lumen with Fluosol-DA.

Conclusions:

• 19F NMR imaging is a promising technique for generating functional and anatomical images in vivo.
• Perfluorochemicals like Fluosol-DA can serve as effective contrast agents for liver and gastrointestinal tract imaging.
• Further development of 19F NMR imaging may lead to novel clinical diagnostic tools.