title: Sequential, co-registered fluorine and proton field-cycled Overhauser imaging at a detection field of 59 mT.
abstract: In this work we show the feasibility of sequential, co-registered fluorine and proton field-cycled Overhauser imaging at a detection field of 59 mT. To this purpose we have built an RF coil assembly comprising an Alderman-Grant resonator for EPR irradiation at 127.7 MHz (evolution field of 4.5 mT) and a solenoidal coil for (19)F or (1)H MRI acquisition at the detection field of 59 mT. A removable tuning/matching circuit that allows the solenoid to be tuned to the (19)F frequency (2.346 MHz, FEDRI) or the (1)H frequency (2.494 MHz, PEDRI) without removing the sample was built and tested. Switching of the solenoid between the (19)F and (1)H frequency is thus achieved in less than 1 min. The co-registered FC-FEDRI and FC-PEDRI images show higher enhancement in the sample regions with higher free radical concentration. This work is the first methodological step towards the development of an MRI scanner capable of acquiring morphological ((1)H) and physiological ((19)F) images in animal models at very low fields.
authors.affiliation: Bio-Medical Physics, School of Medical Sciences, College of Life Sciences & Medicine, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Modica
authors.forename: David J
authors.initials: DJ
authors.lastname: Lurie
authors.forename: Marcello
authors.initials: M
authors.lastname: Alecci
mesh_terms: D003287:Contrast Media; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D004583:Electrons; D005461:Fluorine / Q000737:chemistry*; D005462:Fluorine Radioisotopes; D005609:Free Radicals; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D019047:Phantoms, Imaging; D011522:Protons; D011878:Radiotherapy / Q000379:methods*; D013113:Spin Labels
chemical_list: D003287:Contrast Media; D005462:Fluorine Radioisotopes; D005609:Free Radicals; D011522:Protons; D013113:Spin Labels; D005461:Fluorine