19F Magnetic Resonance Imaging and Spectroscopy in Neuroscience

H-1 magnetic resonance imaging (MRI) has established itself as a key diagnostic technique, affording the visualization of brain anatomy, blood flow, activity and connectivity. The detection of other atoms (e.g. F-19, Na-23, P-31), so called hetero-nuclear MRI and spectroscopy (MRS), provides investigative avenues that complement and extend the richness of information that can be gained from H-1 MRI. Especially F-19 MRI is increasingly emerging as a multi-nuclear (H-1/F-19) technique that can be exploited to visualize cell migration and trafficking. The lack of a F-19 background signal in the brain affords an unequivocal detection suitable for quantification. Fluorine based contrast material can be engineered as nanoemulsions, nanocapsules, or nanoparticles to label cells in vitro or in vivo. Fluorinated blood substitutes, typically nanoemulsions, can also carry oxygen and serve as a theranostic in poorly perfused brain regions. Brain tissue concentrations of fluorinated pharmaceuticals, including inhalation anesthetics (e.g. isoflurane) and anti-depressants (e.g. fluoxetine), can also be measured using MRS. However, the low signal from these compounds provides a challenge for imaging. Further methodological advances that accelerate signal acquisition (e.g. compressed sensing, cryogenic coils) are required to expand the applications of F-19 MR imaging to, for instance, determine the regional pharmacokinetics of novel fluorine-based drugs. Improvements in F-19 signal detection and localization, combined with the development of novel sensitive probes, will increase the utility of these multi-nuclear studies. These advances will provide new insights into cellular and molecular processes involved in neurodegenerative disease, as well as the mode of action of pharmaceutical compounds. This article is part of a Special Issue entitled: Brain imaging. (C) 2021 IBRO. Published by Elsevier Ltd. All rights reserved.

Automated summary

H-1 MRI and multi-nuclear MRI techniques, such as F-19 MRI, allow visualization of brain anatomy, blood flow, and activity, providing rich information. F-19 MRI can also be utilized for visualizing cell migration and treatment. Improvements in F-19 signal detection and introduction of new sensitive probes will enhance the utility of these multi-nuclear studies.