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Dietrich T, Bujak ST, Keller T, Schnackenburg B, Bourayou R, Gebker R, Graf K, Fleck E. In Vivo Fluorine Imaging Using 1.5 Tesla MRI for Depiction of Experimental Myocarditis in a Rodent Animal Model. Int J Biomed Imaging 2023; 2023:4659041. [PMID: 37484527 PMCID: PMC10361831 DOI: 10.1155/2023/4659041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 02/13/2023] [Accepted: 06/04/2023] [Indexed: 07/25/2023] Open
Abstract
The usefulness of perfluorocarbon nanoemulsions for the imaging of experimental myocarditis has been demonstrated in a high-field 9.4 Tesla MRI scanner. Our proof-of-concept study investigated the imaging capacity of PFC-based 19F/1H MRI in an animal myocarditis model using a clinical field strength of 1.5 Tesla. To induce experimental myocarditis, five male rats (weight ~300 g, age ~50 days) were treated with one application per week of doxorubicin (2 mg/kg BW) over a period of six weeks. Three control animals received the identical volume of sodium chloride 0.9% instead. Following week six, all animals received a single 4 ml injection of an 20% oil-in-water perfluorooctylbromide nanoemulsion 24 hours prior to in vivo1H/19F imaging on a 1.5 Tesla MRI. After euthanasia, cardiac histology and immunohistochemistry using CD68/ED1 macrophage antibodies were performed, measuring the inflamed myocardium in μm2 for further statistical analysis to compare the extent of the inflammation with the 19F-MRI signal intensity. All animals treated with doxorubicin showed a specific signal in the myocardium, while no myocardial signal could be detected in the control group. Additionally, the doxorubicin group showed a significantly higher SNR for 19F and a stronger CD68/ED1 immunhistoreactivity compared to the control group. This proof-of-concept study demonstrates that perfluorocarbon nanoemulsions could be detected in an in vivo experimental myocarditis model at a currently clinically relevant field strength.
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Affiliation(s)
- Thore Dietrich
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
| | - Stephan Theodor Bujak
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
- Department of Geriatrics, Krankenhaus Hedwigshöhe, Alexianer St. Hedwig Kliniken Berlin GmbH, Berlin 12526, Germany
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin 10117, Germany
| | - Thorsten Keller
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
- B. Braun Melsungen AG, Melsungen 34212, Germany
| | | | - Riad Bourayou
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
| | - Rolf Gebker
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
| | - Kristof Graf
- Department of Cardiology, Jüdisches Krankenhaus Berlin, Berlin 13347, Germany
| | - Eckart Fleck
- Department of Cardiology, Deutsches Herzzentrum Berlin, Berlin 13353, Germany
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Small-scale preparation of perfluorocarbon-nanoemulsions utilizing dual centrifugation. Int J Pharm 2019; 572:118753. [PMID: 31678380 DOI: 10.1016/j.ijpharm.2019.118753] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/27/2019] [Accepted: 09/29/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND Perfluorocarbon-nanoemulsions (PFC-NE) made of PFC and phospholipids (PL) by homogenization are optimal for in vivo-19F labelling of monocytes and subsequently of inflamed tissues in magnetic resonance imaging (MRI). Necessary requirements for in vivo use of PFC-NE are sterility, suitable droplet sizes and the absence of immune activating liposomes, which are a typical byproduct of the homogenization process. METHODS AND RESULTS To meet these requirements, we developed an aseptic in-vial preparation technique for PFC-NE based on dual centrifugation (DC) by testing different PFC/phospholipid ratios as well as the application of additives. Two different PFC, perfluorooctylbromide (PFOB) and perfluoro-15-crown-5-ether (PFCE), were investigated. Particle sizes were assessed by dynamic light scattering and NE morphology by cryoTEM. DC homogenization was optimal when using an excess of PL (8.7 % (m/m) of utilized PFC, z-ave: 180 nm, pdi: 0.2). A purification approach by centrifugation was implemented to remove liposomes formed from the excess of PL during homogenization. The purification success was proven by phospholipid assay and PFC quantification via density and sound velocity measurements. CONCLUSION DC in combination with a short centrifugation is a fast and reliable way of small-scale aseptic PFC-NE production for 19F MRI passive-targeting experiments of monocytes and inflamed tissues.
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Ghuman H, Hitchens TK, Modo M. A systematic optimization of 19F MR image acquisition to detect macrophage invasion into an ECM hydrogel implanted in the stroke-damaged brain. Neuroimage 2019; 202:116090. [PMID: 31408717 DOI: 10.1016/j.neuroimage.2019.116090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 08/06/2019] [Accepted: 08/08/2019] [Indexed: 02/08/2023] Open
Abstract
19F-MR imaging of perfluorocarbon (PFC)-labeled macrophages can provide a unique insight into their participation and spatio-temporal dynamics of inflammatory events, such as the biodegradation of an extracellular matrix (ECM) hydrogel implanted into a stroke cavity. To determine the most efficient acquisition strategy for 19F-MR imaging, five commonly used sequences were optimized using a design of experiment (DoE) approach and compared based on their signal-to-noise ratio (SNR). The fast imaging with steady-state precession (FISP) sequence produced the most efficient detection of a 19F signal followed by the rapid acquisition with relaxation enhancement (RARE) sequence. The multi-slice multi-echo (MSME), fast low angle shot (FLASH), and zero echo time (ZTE) sequences were significantly less efficient. Imaging parameters (matrix/voxel size; slice thickness, number of averages) determined the accuracy (i.e. trueness and precision) of object identification by reducing partial volume effects, as determined by analysis of the point spread function (PSF). A 96 × 96 matrix size (0.35 mm3) produced the lowest limit of detection (LOD) for RARE (2.85 mM PFPE; 119 mM 19F) and FISP (0.43 mM PFPE; 18.1 mM 19F), with an SNR of 2 as the detection threshold. Imaging of a brain phantom with PFC-labeled macrophages invading an ECM hydrogel further illustrated the impact of these parameter changes. The systematic optimization of sequence and imaging parameters provides the framework for an accurate visualization of 19F-labeled macrophage distribution and density in the brain. This will enhance our understanding of the contribution of periphery-derived macrophages in bioscaffold degradation and its role in brain tissue regeneration.
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Affiliation(s)
- Harmanvir Ghuman
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - T Kevin Hitchens
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michel Modo
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA; Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA.
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Jahromi AH, Wang C, Adams SR, Zhu W, Narsinh K, Xu H, Gray DL, Tsien RY, Ahrens ET. Fluorous-Soluble Metal Chelate for Sensitive Fluorine-19 Magnetic Resonance Imaging Nanoemulsion Probes. ACS NANO 2019; 13:143-151. [PMID: 30525446 PMCID: PMC6467752 DOI: 10.1021/acsnano.8b04881] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Fluorine-19 MRI is an emerging cellular imaging approach, enabling lucid, quantitative "hot-spot" imaging with no background signal. The utility of 19F-MRI to detect inflammation and cell therapy products in vivo could be expanded by improving the intrinsic sensitivity of the probe by molecular design. We describe a metal chelate based on a salicylidene-tris(aminomethyl)ethane core, with solubility in perfluorocarbon (PFC) oils, and a potent accelerator of the 19F longitudinal relaxation time ( T1). Shortening T1 can increase the 19F image sensitivity per time and decrease the minimum number of detectable cells. We used the condensation between the tripodal ligand tris-1,1,1-(aminomethyl)ethane and salicylaldehyde to form the salicylidene-tris(aminomethyl)ethane chelating agent (SALTAME). We purified four isomers of SALTAME, elucidated structures using X-ray scattering and NMR, and identified a single isomer with high PFC solubility. Mn4+, Fe3+, Co3+, and Ga3+ cations formed stable and separable chelates with SALTAME, but only Fe3+ yielded superior T1 shortening with modest line broadening at 3 and 9.4 T. We mixed Fe3+ chelate with perfluorooctyl bromide (PFOB) to formulate a stable paramagnetic nanoemulsion imaging probe and assessed its biocompatibility in macrophages in vitro using proliferation, cytotoxicity, and phenotypic cell assays. Signal-to-noise modeling of paramagnetic PFOB shows that sensitivity enhancement of nearly 4-fold is feasible at clinical magnetic field strengths using a 19F spin-density-weighted gradient-echo pulse sequence. We demonstrate the utility of this paramagnetic nanoemulsion as an in vivo MRI probe for detecting inflammation macrophages in mice. Overall, these paramagnetic PFC compounds represent a platform for the development of sensitive 19F probes.
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Affiliation(s)
- Amin Haghighat Jahromi
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
| | - Chao Wang
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
| | - Stephen R. Adams
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Wenlian Zhu
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
| | - Kazim Narsinh
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Hongyan Xu
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
| | - Danielle L. Gray
- School of Chemical Sciences, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
| | - Roger Y. Tsien
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, California 92093, United States
| | - Eric T. Ahrens
- Department of Radiology, University of California, San Diego, La Jolla, California 92093, United States
- Corresponding Author: (E. T. Ahrens) Phone: (858) 246-0279.
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Bouvain P, Flocke V, Krämer W, Schubert R, Schrader J, Flögel U, Temme S. Dissociation of 19F and fluorescence signal upon cellular uptake of dual-contrast perfluorocarbon nanoemulsions. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2018; 32:133-145. [PMID: 30498884 DOI: 10.1007/s10334-018-0723-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/31/2018] [Accepted: 11/21/2018] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Perfluorocarbon nanoemulsions (PFCs) tagged with fluorescence dyes have been intensively used to confirm the in vivo 19F magnetic resonance imaging (MRI) localization of PFCs by post mortem histology or flow cytometry. However, only limited data are available on tagged PFCs and the potential dissociation of fluorescence and 19F label after cellular uptake over time. MATERIALS AND METHODS PFCs were coupled to rhodamine (Rho) or carboxyfluorescein (Cfl) and their fate was analyzed after in vitro uptake by J774, RAW and CHO cells by flow cytometry and 19F MRI. In separate in vivo experiments, the dual-labelled emulsions were intravenously applied into mice and their distribution was monitored in spleen and liver over 24 h. In a final step, time course of fluorescence and 19F signals from injected emulsions were tracked in a local inflammation model making use of a subcutaneous matrigel depot doped with LPS (lipopolysaccharide). RESULTS Internalization of fluorescence-labelled PFCs was associated with a substantial whitening over 24 h in all macrophage cell lines while the 19F signal remained stable over time. In all experiments, CflPFCs were more susceptible to bleaching than RhoPFCs. After intravenous injection of RhoPFCs, the fluorescence signal in spleen and liver peaked after 30 min and 2 h, respectively, followed by a successive decrease over 24 h, whereas the 19F signal continuously increased during this observation period. Similar results were found in the matrigel/LPS model, where we observed increasing 19F signals in the inflammatory hot spot over time while the fluorescence signal of immune cells isolated from the matrigel depot 24 h after its implantation was only marginally elevated over background levels. This resulted in a massive underestimation of the true PFC deposition in the reticuloendothelial system and at inflammatory hot spots. CONCLUSION Cellular uptake of fluorescently tagged PFCs leads to a dissociation of the fluorescence and the 19F label signal over time, which critically impacts on interpretation of long-term experiments validated by histology or flow cytometry.
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Affiliation(s)
- Pascal Bouvain
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University of Düsseldorf, Düsseldorf, NRW, Germany
| | - Vera Flocke
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University of Düsseldorf, Düsseldorf, NRW, Germany
- Department of Engineering Physics, University of Applied Science Münster, Münster, Germany
| | - Wolfgang Krämer
- Pharmaceutical Technology and Biopharmacy, Albert Ludwigs University, Freiburg, BW, Germany
| | - Rolf Schubert
- Pharmaceutical Technology and Biopharmacy, Albert Ludwigs University, Freiburg, BW, Germany
| | - Jürgen Schrader
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University of Düsseldorf, Düsseldorf, NRW, Germany
| | - Ulrich Flögel
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University of Düsseldorf, Düsseldorf, NRW, Germany.
| | - Sebastian Temme
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University of Düsseldorf, Düsseldorf, NRW, Germany
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Rothe M, Jahn A, Weiss K, Hwang JH, Szendroedi J, Kelm M, Schrader J, Roden M, Flögel U, Bönner F. In vivo 19F MR inflammation imaging after myocardial infarction in a large animal model at 3 T. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2018; 32:5-13. [DOI: 10.1007/s10334-018-0714-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/04/2018] [Accepted: 10/22/2018] [Indexed: 12/19/2022]
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Tirotta I, Dichiarante V, Pigliacelli C, Cavallo G, Terraneo G, Bombelli FB, Metrangolo P, Resnati G. (19)F magnetic resonance imaging (MRI): from design of materials to clinical applications. Chem Rev 2014; 115:1106-29. [PMID: 25329814 DOI: 10.1021/cr500286d] [Citation(s) in RCA: 327] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ilaria Tirotta
- Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering "Giulio Natta" and ‡Fondazione Centro Europeo Nanomedicina, Politecnico di Milano , Milan 20131, Italy
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Ahrens ET, Zhong J. In vivo MRI cell tracking using perfluorocarbon probes and fluorine-19 detection. NMR IN BIOMEDICINE 2013; 26:860-71. [PMID: 23606473 PMCID: PMC3893103 DOI: 10.1002/nbm.2948] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 01/29/2013] [Accepted: 02/21/2013] [Indexed: 05/08/2023]
Abstract
This article presents a brief review of preclinical in vivo cell-tracking methods and applications using perfluorocarbon (PFC) probes and fluorine-19 ((19) F) MRI detection. Detection of the (19) F signal offers high cell specificity and quantification ability in spin density-weighted MR images. We discuss the compositions of matter, methods and applications of PFC-based cell tracking using ex vivo and in situ PFC labeling in preclinical studies of inflammation and cellular therapeutics. We also address the potential applicability of (19) F cell tracking to clinical trials.
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Affiliation(s)
- Eric T Ahrens
- Department of Biological Sciences and Pittsburgh NMR Center for Biomedical Research, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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den Adel B, van der Graaf LM, Que I, Strijkers GJ, Löwik CW, Poelmann RE, van der Weerd L. Contrast enhancement by lipid-based MRI contrast agents in mouse atherosclerotic plaques; a longitudinal study. CONTRAST MEDIA & MOLECULAR IMAGING 2013; 8:63-71. [PMID: 23109394 DOI: 10.1002/cmmi.1496] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The use of contrast-enhanced MRI to enable in vivo specific characterization of atherosclerotic plaques is increasing. In this study the intrinsic ability of two differently sized gadolinium-based contrast agents to enhance atherosclerotic plaques in ApoE(-/-) mice was evaluated with MRI. We obtained a kinetic profile for contrast enhancement, as the literature data on optimal imaging time points is scarce, and assessed the longer-term kinetics. Signal enhancement in the wall of the aortic arch, following intravenous injection of paramagnetic micelles and liposomes, was followed for 1 week. In vivo T(1)-weighted MRI plaque enhancement characteristics were complemented by fluorescence microscopy of NIR(664) incorporated in the contrast agents and quantification of tissue and blood Gd-DTPA. Both micelles and liposomes enhanced contrast in T(1)-weighted MR images of plaques in the aortic arch. The average contrast-to-noise ratio increased after liposome or micelle injection to 260 or 280% respectively, at 24 h after injection, compared with a pre-scan. A second wave of maximum contrast enhancement was observed around 60-72 h after injection, which only slowly decreased towards the 1 week end-point. Confocal fluorescence microscopy and whole body fluorescence imaging confirmed MRI-findings of accumulation of micelles and liposomes. Plaque permeation of contrast agents was not strongly dependent on the contrast agent size in this mouse model. Our results show that intraplaque accumulation over time of both contrast agents leads to good plaque visualization for a long period. This inherent intraplaque accumulation might make it difficult to discriminate passive from targeted accumulation. This implies that, in the development of targeted contrast agents on a lipid-based backbone, extensive timing studies are required.
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Affiliation(s)
- Brigit den Adel
- Department of Anatomy and Embryology, Leiden University Medical Center, the Netherlands
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Kadayakkara DK, Ranganathan S, Young WB, Ahrens ET. Assaying macrophage activity in a murine model of inflammatory bowel disease using fluorine-19 MRI. J Transl Med 2012; 92:636-45. [PMID: 22330343 PMCID: PMC3397682 DOI: 10.1038/labinvest.2012.7] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Macrophages have an important role in the pathogenesis of most chronic inflammatory diseases. A means of non-invasively quantifying macrophage migration would contribute significantly towards our understanding of chronic inflammatory processes and aid the evaluation of novel therapeutic strategies. We describe the use of a perfluorocarbon tracer reagent and in vivo (19)F magnetic resonance imaging (MRI) to quantify macrophage burden longitudinally. We apply these methods to evaluate the severity and three-dimensional distribution of macrophages in a murine model of inflammatory bowel disease (IBD). MRI results were validated by histological analysis, immunofluorescence and quantitative real-time polymerase chain reaction. Selective depletion of macrophages in vivo was also performed, further validating that macrophage accumulation of perfluorocarbon tracers was the basis of (19)F MRI signals observed in the bowel. We tested the effects of two common clinical drugs, dexamethasone and cyclosporine A, on IBD progression. Whereas cyclosporine A provided mild therapeutic effect, unexpectedly dexamethasone enhanced colon inflammation, especially in the descending colon. Overall, (19)F MRI can be used to evaluate early-stage inflammation in IBD and is suitable for evaluating putative therapeutics. Due to its high macrophage specificity and quantitative ability, we envisage (19)F MRI having an important role in evaluating a wide range of chronic inflammatory conditions mediated by macrophages.
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Affiliation(s)
- Deepak K Kadayakkara
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Sarangarajan Ranganathan
- Department of Pathology, University of Pittsburgh School of Medicine, Children’s Hospital of Pittsburgh, One Children’s Hospital Drive, Pittsburgh, PA, USA
| | - Won-Bin Young
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric T Ahrens
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
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Giraudeau C, Djemaï B, Ghaly MA, Boumezbeur F, Mériaux S, Robert P, Port M, Robic C, Le Bihan D, Lethimonnier F, Valette J. High sensitivity 19F MRI of a perfluorooctyl bromide emulsion: application to a dynamic biodistribution study and oxygen tension mapping in the mouse liver and spleen. NMR IN BIOMEDICINE 2012; 25:654-660. [PMID: 21953998 DOI: 10.1002/nbm.1781] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 07/12/2011] [Accepted: 07/14/2011] [Indexed: 05/31/2023]
Abstract
We have recently developed an optimized multi-spin echo (MSE) sequence dedicated to perfluorooctyl bromide (PFOB) imaging yielding an excellent sensitivity in vitro. The aim of the present study was to apply this sequence to quantitative measurements in the mouse liver and spleen after intravenous (i.v.) injection of PFOB emulsions. We first performed oxygenation maps 25.5 min after a single infusion of emulsion and, contrary to previous studies, shortly after injection. The signal-to-noise ratio (SNR) in the liver and spleen was as high as 45 and 120, respectively, for 3-min images with 11.7-μL pixels. Values of oxygen tension tended to be slightly higher in the spleen than in the liver. Dynamic biodistribution experiments were then performed immediately after intravenous (i.v.) injection of PFOB emulsions grafted with different quantities of polyethylene glycol (PEG) for stealth. Images were acquired every 7 min for 84 min and the SNR measured in the liver and spleen was at least four from the first time point. Uptake rates could be assessed for each PEG amount and, in spite of high standard deviations (SDs) owing to interanimal variability, our data confirmed that increasing quantities of PEG allow more gradual uptake of the emulsion particles by the liver and spleen. In conclusion, our method seems to be a powerful tool to non-invasively perform accurate in vivo quantitative measurements in the liver and spleen using (19)F MRI.
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Affiliation(s)
- Céline Giraudeau
- Commissariat à l'Energie Atomique (CEA), Institut d'Imagerie Biomédicale (I²BM), NeuroSpin, CEA Saclay, Gif-sur-Yvette cedex, France
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12
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Youn H, Hong KJ. In vivo Noninvasive Small Animal Molecular Imaging. Osong Public Health Res Perspect 2012; 3:48-59. [PMID: 24159487 PMCID: PMC3738683 DOI: 10.1016/j.phrp.2012.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 02/13/2012] [Accepted: 02/13/2012] [Indexed: 12/16/2022] Open
Abstract
The remarkable efforts that are made on molecular imaging technologies demonstrate its potential importance and range of applications. The generation of disease-specific animal models, and the developments of target-specific probes and genetically encoded reporters are another important component. Continued improvements in the instrumentation, the identification of novel targets and genes, and the availability of improved imaging probes should be made. Multimodal imaging probes should provide easier transitions between laboratory studies, including small animal studies and clinical applications. Here, we reviewed basic strategies of noninvasive in vivo imaging methods in small animals to introducing the concept of molecular imaging.
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Affiliation(s)
- Hyewon Youn
- Department of Nuclear Medicine, Cancer Imaging Center, Seoul National University Cancer Hospital, Seoul, Korea
- Laboratory of Molecular Imaging and Therapy, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Kee-Jong Hong
- Division of High-Risk Pathogen Research, Korea National Institute of Health, Osong, Korea
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13
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Abstract
One of the greatest challenges to study the structure, function, and molecules in the living brain is that it is enclosed within the skull and difficult to access. Although biopsies are feasible, they are invasive, could lead to functional impairments, and in any case will only provide a small regional sample that is not necessarily reflecting the entire brain. Since the beginning of the twentieth century, in vivo imaging has gradually, and steadily, matured into non-invasive techniques that enable the repeated investigation of the structural, functional, cellular, and molecular composition of the brain. Not only is this information of great importance to scientists aiming to understand how the brain works, but these techniques are also essential to physicians who use imaging to diagnose and treat disease. The current book is a collection of 29 cutting-edge methods and protocols that are used in the current field of neuroimaging.
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Affiliation(s)
- Michel Modo
- Department of Neuroscience, Kings College London, Institute of Psychiatry, Centre for the Cellular Basis of Behaviour, The James Black Centre, London, UK.
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14
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Giraudeau C, Flament J, Marty B, Boumezbeur F, Mériaux S, Robic C, Port M, Tsapis N, Fattal E, Giacomini E, Lethimonnier F, Le Bihan D, Valette J. A new paradigm for high-sensitivity19F magnetic resonance imaging of perfluorooctylbromide. Magn Reson Med 2010; 63:1119-24. [DOI: 10.1002/mrm.22269] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Janjic JM, Ahrens ET. Fluorine-containing nanoemulsions for MRI cell tracking. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2009; 1:492-501. [PMID: 19920872 PMCID: PMC2777673 DOI: 10.1002/wnan.35] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this article we review the chemistry and nanoemulsion formulation of perfluorocarbons used for in vivo(19)F MRI cell tracking. In this application, cells of interest are labeled in culture using a perfluorocarbon nanoemulsion. Labeled cells are introduced into a subject and tracked using (19)F MRI or NMR spectroscopy. In the same imaging session, a high-resolution, conventional ((1)H) image can be used to place the (19)F-labeled cells into anatomical context. Perfluorocarbon-based (19)F cell tracking is a useful technology because of the high specificity for labeled cells, ability to quantify cell accumulations, and biocompatibility. This technology can be widely applied to studies of inflammation, cellular regenerative medicine, and immunotherapy.
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Affiliation(s)
- Jelena M. Janjic
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Eric T. Ahrens
- Department of Biological Sciences and Pittsburgh NMR Center for Biomedical Research, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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16
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Gillies RJ, Raghunand N, Karczmar GS, Bhujwalla ZM. MRI of the tumor microenvironment. J Magn Reson Imaging 2002; 16:430-50. [PMID: 12353258 DOI: 10.1002/jmri.10181] [Citation(s) in RCA: 412] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The microenvironment within tumors is significantly different from that in normal tissues. A major difference is seen in the chaotic vasculature of tumors, which results in unbalanced blood supply and significant perfusion heterogeneities. As a consequence, many regions within tumors are transiently or chronically hypoxic. This exacerbates tumor cells' natural tendency to overproduce acids, resulting in very acidic pH values. The hypoxia and acidity of tumors have important consequences for antitumor therapy and can contribute to the progression of tumors to a more aggressive metastatic phenotype. Over the past decade, techniques have emerged that allow the interrogation of the tumor microenvironment with high resolution and molecularly specific probes. Techniques are available to interrogate perfusion, vascular distribution, pH, and pO(2) nondestructively in living tissues with relatively high precision. Studies employing these methods have provided new insights into the causes and consequences of the hostile tumor microenvironment. Furthermore, it is quite exciting that there are emerging techniques that generate tumor image contrast via ill-defined mechanisms. Elucidation of these mechanisms will yield further insights into the tumor microenvironment. This review attempts to identify techniques and their application to tumor biology, with an emphasis on nuclear magnetic resonance (NMR) approaches. Examples are also discussed using electron MR, optical, and radionuclear imaging techniques.
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Affiliation(s)
- Robert J Gillies
- Department of Biochemistry, Arizona Cancer Center, University of Arizona HSC, Tucson, Arizona 85724-5024, USA.
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17
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Nöth U, Gröhn P, Jork A, Zimmermann U, Haase A, Lutz J. 19F-MRI in vivo determination of the partial oxygen pressure in perfluorocarbon-loaded alginate capsules implanted into the peritoneal cavity and different tissues. Magn Reson Med 1999; 42:1039-47. [PMID: 10571925 DOI: 10.1002/(sici)1522-2594(199912)42:6<1039::aid-mrm8>3.0.co;2-n] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Semipermeable hydrogels formed with a biocompatible alginate solution and Ba(2+) ions protect encapsulated cells and tissues from a foreign immune system. For the viability and metabolic activity of the encapsulated materials, a sufficient oxygen supply inside the capsules is necessary. Quantitative (19)F-MRI was performed on perfluorocarbon-loaded alginate capsules implanted into the peritoneal cavity, the musculus quadriceps femoris, and beneath the kidney capsule of rats, in order to determine in vivo the partial oxygen pressure (pO(2)) inside the capsules at these implantation sites. The temporal behavior of the pO(2) values was observed for at least 3 months. The most stable values over time were observed in the kidney, where inter-rat pO(2) differences were considerable. In the muscle, the values were very high directly after implantation and decreased to nearly zero after 2 weeks. In the peritoneal cavity, values changed randomly over a wide range between different rats and over time. Magn Reson Med 42:1039-1047, 1999.
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Affiliation(s)
- U Nöth
- Physikalisches Institut, Lehrstuhl für Biophysik, Am Hubland, Würzburg, Germany
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18
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Sogabe T, Imaizumi T, Mori T, Tominaga M, Koga K, Yabuuchi Y. Effects of vasodilators on the signal intensity of perfluorocarbon monitored by in vivo 19F-NMR spectroscopy. Magn Reson Imaging 1997; 15:341-5. [PMID: 9201682 DOI: 10.1016/s0730-725x(96)00382-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effects of vasodilators on peripheral vessels were examined by monitoring the 19F-NMR signal of perfluorocarbon in vivo. Nitroglycerin, a venodilator that acts mainly on venous smooth muscle, increased the signal intensity of FC-43, whereas hydralazine, a typical arteriolar dilator that acts on arteriolar smooth muscle, decreased the signal intensity. These results indicate that the in vivo effects of vasodilators on smooth muscles of the venous and arterial systems are reflected by their effects on the signal intensity of FC-43.
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Affiliation(s)
- T Sogabe
- Tokushima Research Institute, Otsuka Pharmaceutical Co., Ltd., Japan
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19
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Webb AG, Wong M, Kolbeck KJ, Magin R, Suslick KS. Sonochemically produced fluorocarbon microspheres: a new class of magnetic resonance imaging agent. J Magn Reson Imaging 1996; 6:675-83. [PMID: 8835962 DOI: 10.1002/jmri.1880060417] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
With the intent of increasing the signal-to-noise ratio (SNR) of fluorine magnetic resonance imaging and enabling new applications, we have developed a novel class of agents based on protein encapsulation of fluorocarbons. Microspheres formed by high-intensity ultrasound have a gaussian size distribution with an average diameter of 2.5 microns. As with conventional emulsions, these microspheres target the reticuloendothelial system. However, our sonochemically produced microspheres, because of a high encapsulation efficiency, show increases in the SNR of up to 300% compared to commercially available emulsions. We also demonstrate an increase in the circulation lifetime of the microspheres with the bloodstream by more than 30-fold with a chemical modification of the outer surface of the microsphere. Finally, by encapsulating mixtures of fluorocarbons that undergo solid/liquid phase transitions, we can map temperature in the reticuloendothelial system, with signal changes of approximately 20-fold over a 5 degrees C range.
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Affiliation(s)
- A G Webb
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
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20
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Rottman GA, Judd RM, Yin FC. Validation of 19F-magnetic resonance determination of myocardial blood volume. Magn Reson Med 1995; 34:628-31. [PMID: 8524033 DOI: 10.1002/mrm.1910340421] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The use of perfluorochemical (PFC) emulsions to study the myocardial circulation by means of 19F NMR requires that the biodistribution of the PFC be known. The authors tested the hypothesis that PFC particles remain within the myocardial vascular space by infusing rats with both a PFC emulsion and 125I-albumin. Measurement of myocardial vascular volume by 19F NMR and by standard radiotracer analysis of the same tissue yielded concordant values by the two methods, establishing the PFC emulsion as an intravascular agent in this tissue. Perfluorochemical emulsions should be useful for the noninvasive study of myocardial vascular physiology by magnetic resonance.
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Affiliation(s)
- G A Rottman
- Department of Radiology, Johns Hopkins Medical Institutes, Baltimore, Maryland, USA
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21
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Dardzinski BJ, Sotak CH. Rapid tissue oxygen tension mapping using 19F inversion-recovery echo-planar imaging of perfluoro-15-crown-5-ether. Magn Reson Med 1994; 32:88-97. [PMID: 8084241 DOI: 10.1002/mrm.1910320112] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Fluorine-19 inversion-recovery, echo-planar imaging (IR-EPI) was used in conjunction with a new PFC emulsion, perfluoro-15-crown-5-ether, to map the spatial distribution of oxygen tension in murine liver, spleen and radiation induced fibrosarcoma (RIF-1) tumors. Intravenously administered PFC emulsions were allowed to sequester in the liver, spleen, and tumor 3 to 7 days prior to imaging experiments. Seven, 64 x 64 IR-EPIs were acquired with successively increasing inversion times (TI). A nonlinear least-squares regression algorithm was used to fit the seven two-dimensional matrices, on a pixel-by-pixel basis, to solve for the relaxation rate, R1, of the sequestered PFC. From in vitro calibration curves, the oxygen tension (pO2) was calculated from the measured R1. Oxygen tension maps were then murine liver and spleen were produced (in 2.5 min) to demonstrate the technique and changes in tissue oxygenation as a function of breathing gas (air and carbogen (95% O2-5% CO2)) are presented. Tissue pO2 maps from RIF-1 tumors (n = 5) were obtained in less than 10 min and changes in tumor pO2 were studied when the breathing gas was switched from air to carbogen. The results from tumor pO2 maps were compared with 19F MR spectroscopy measurements to check for consistency. Histogram analysis yielded an average liver and spleen pO2 of 43 torr and 26 torr for RIF-1 tumors when the animals were breathing air. Statistically significant changes in tumor oxygenation as a function of breathing gas were obtained from both pO2 maps (6 +/- 2 torr, P < 0.05) and 19F MR spectroscopy (13 +/- 3 torr, P < 0.01) as evaluated using the Student's paired t test.
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Affiliation(s)
- B J Dardzinski
- Department of Biomedical Engineering, Worcester Polytechnic Institute, MA 01609
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22
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Mason RP. Non-invasive physiology: 19F NMR of perfluorocarbons. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1994; 22:1141-53. [PMID: 7849916 DOI: 10.3109/10731199409138809] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Ever since it was shown that the 19F NMR spin-lattice relaxation rates (R1) of perfluorocarbon (PFC) emulsions are highly sensitive to oxygen tension (pO2), there has been a developing interest in the use of PFCs to probe tissue physiology. Oxygen is required for efficient function by most tissues and hypoxia leads to rapid cellular dysfunction and damage. In addition, hypoxic tumor cells are refractory to radiotherapy. Thus, the opportunity to measure tissue oxygen tension non-invasively may be significant in understanding mechanisms of tissue function and in clinical prognosis. PFC NMR parameters are also sensitive to temperature, facilitating NMR thermometry with potential applications in hyperthermia studies. I will review the development of experimental techniques, applications to specific tissues and discuss the challenges and opportunities presented by 19F NMR of perfluorocarbons.
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Affiliation(s)
- R P Mason
- Department of Radiology, UT-Southwestern Medical Center, Dallas 75235-9058
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23
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Jäger LJ, Nöth U, Haase A, Lutz J. Half-life of perfluorooctylbromide in inner organs determined by fast 19F-NMR imaging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1994; 361:129-34. [PMID: 7597935 DOI: 10.1007/978-1-4615-1875-4_17] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- L J Jäger
- Institute of Radiology, University of Bonn, Germany
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24
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Abstract
The goal of this study was the development of a method that allows the acquisition of chemical shift selective 19F NMR images within a short measuring time. A train of small tip angle frequency selective pulses, each followed by a dephasing gradient of random strength, was used as a presaturation experiment for the suppression of the unwanted chemical shift components. Imaging was performed after presaturation using a SNAPSHOT-FLASH experiment. The acquisition time for a 64 x 128 image including the presaturation experiment amounted to only 470 ms. The sequence was applied in a 4.7 Tesla magnet to perform a longitudinal pharmacological study on the clearance of perfluoroocytlbromide (PFOB) in the liver and spleen of rats.
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Affiliation(s)
- U Nöth
- Physikalisches Institut, Universität Würzburg, Germany
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25
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Sotak CH, Hees PS, Huang HN, Hung MH, Krespan CG, Raynolds S. A new perfluorocarbon for use in fluorine-19 magnetic resonance imaging and spectroscopy. Magn Reson Med 1993; 29:188-95. [PMID: 8429782 DOI: 10.1002/mrm.1910290206] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A new perfluorocarbon, PTBD (perfluoro-2,2,2',2'-tetramethyl-4,4'-bis(1,3-dioxolane)), is described for use in 19F MR imaging and spectroscopy. Two-thirds of the molecular fluorine in PTBD resonates at a single frequency and can be imaged without the use of frequency-selective spin-echo (SE) MRI pulse sequences to suppress chemical shift artifacts. The absence of strong homonuclear spin-spin coupling to the imagable -CF3 groups in PTBD minimizes signal attenuation in 19F SE MRI due to J-modulation effects. For equimolar concentrations of perfluorocarbon, PTBD gives an approximately 17% increase in sensitivity, relative to literature results for perfluorinated amines, at short values of TE (approximately 10 ms) in 19F SE MRI. These attributes allow 19F MRI of PTBD to be performed on standard clinical imaging instrumentation (without special hardware and/or software modification) and an in vivo example in a mouse is shown. This investigation involved characterizing the MR T1 and T2 relaxation times of PTBD as well as the MR spin-lattice relaxation rate, R1 (1/T1), of PTBD as a function of dissolved oxygen concentration. The T1 and T2 relaxation times and R1 relaxation rates of perfluorooctyl bromide (PFOB) were also obtained, under similar experimental conditions, to compare and contrast PTBD with a representative perfluorocarbon that has been widely employed for 19F MRI/MRS applications.
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Affiliation(s)
- C H Sotak
- Department of Biomedical Engineering, Worcester Polytechnic Institute, MA 01609
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26
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Börnert P, Norris DG, Koch H, Dreher W, Reichelt H, Leibfritz D. Fast perfluorocarbon imaging using 19F U-FLARE. Magn Reson Med 1993; 29:226-34. [PMID: 8429787 DOI: 10.1002/mrm.1910290211] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The application of an ultra-fast low angle RARE technique for the 19F imaging of perfluorocarbons (PFCs) used as temporary blood substitutes is described. This sequence is attractive for fast 19F imaging studies that measure the biodistribution of PFCs in vivo, due to its high signal-to-noise ratio. Extensions of this technique for the chemical shift selective measurement of fluorine T1 values are presented. Using the linear dependence between the oxygen partial pressure (pO2) and the T1 relaxation rate of PFC resonances this technique makes possible the fast in vivo measurement of oxygen tension. Using the sequence in a diffusion sensitized form 19F measurements of the diffusion constants of PFCs are also presented. Phantom experiments to test the methods, and in vivo images obtained in rat studies are given and discussed.
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27
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Brix G, Bellemann ME, Zabel HJ, Bachert P, Lorenz WJ. Selective 19F MR imaging of 5-fluorouracil and alpha-fluoro-beta-alanine. Magn Reson Imaging 1993; 11:1193-201. [PMID: 8271906 DOI: 10.1016/0730-725x(93)90247-b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A 19F MR chemical shift imaging (CSI) technique is presented which enables selective imaging of the antineoplastic drug 5-fluorouracil (5-FU) and its major catabolite alpha-fluoro-beta-alanine (FBAL). The CSI sequence employs a chemical shift selective (CHESS) saturation pulse to suppress either the 5-FU or the FBAL resonance before the other component of the two-line 19F MR spectrum is measured. Because the transmitter frequency can always be set to the Larmor frequency of the 19F resonance to be imaged, this approach yields 5-FU and FBAL MR images free of chemical shift artifacts in read-out and slice-selection direction. In phantom experiments, selective 5-FU and FBAL images with a spatial resolution of 15 x 15 x 20 mm3 (4.5 ml) were obtained in 30 min from a model solution, whose drug and catabolite concentrations were similar to those estimated in the liver of tumor patients undergoing IV chemotherapy with 5-FU. The drug-specific MR imaging technique developed is, therefore, well-suited for the direct and noninvasive monitoring of the up-take and trapping of 5-FU in liver tumors in vivo.
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Affiliation(s)
- G Brix
- Research Program Radiological Diagnostics and Therapy, German Cancer Research Center (DKFZ), Heidelberg
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28
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Ruiz-Cabello J, Cohen JS. NMR and the study of pathological state in cells and tissues. INTERNATIONAL REVIEW OF CYTOLOGY 1993; 145:1-63. [PMID: 8500979 DOI: 10.1016/s0074-7696(08)60424-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- J Ruiz-Cabello
- Department of Pharmacology, Georgetown University Medical School, Washington, D.C. 20007
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29
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Judd RM, Rottman GA, Forder JR, Yin FC, Blackband SJ. Feasibility of 19F imaging of perfluorochemical emulsions to measure myocardial vascular volume. Magn Reson Med 1992; 28:129-36. [PMID: 1435216 DOI: 10.1002/mrm.1910280113] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
19F magnetic resonance images were obtained of the ventricular walls of isolated rabbit hearts perfused with a perfluorochemical (PFC) emulsion. Since the PFC is known to stay within the vascular space in normal myocardial tissue, the 19F signal should reflect myocardial vascular volume. 19F MRI of PFC emulsions represents a new investigational tool for the study of coronary vascular volume.
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Affiliation(s)
- R M Judd
- Department of Biomedical Engineering, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
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30
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31
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Prior MJW, Maxwell RJ, Griffiths JR. Fluorine-19F NMR Spectroscopy and Imaging In-Vivo. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/978-3-642-77218-4_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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32
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Mishima H, Kobayashi T, Shimizu M, Tamaki Y, Baba M, Shimano T, Itoh S, Yamazaki M, Iriguchi N, Takahashi M. In vivo F-19 chemical shift imaging with FTPA and antibody-coupled FMIQ. J Magn Reson Imaging 1991; 1:705-9. [PMID: 1823176 DOI: 10.1002/jmri.1880010616] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A mixture of perfluoromethyldecahydroisoquinoline (FMIQ) emulsion coupled with anti-CEA (carcinoembryonic antigen) antibody and perfluorotripropylamine (FTPA) was injected into a nude mouse inoculated with human colon carcinoma LS174T. Three days after the injection, in vivo fluorine-19 chemical shift images of the spectral signals of the two perfluorocarbons (PFCs) were obtained simultaneously. The signal intensities and distributions of FMIQ and FTPA were similar in the liver and spleen but different in the tumor. FMIQ was detected in almost the entire tumor, with scattered areas of high uptake. FTPA, however, was detected only in the center of the tumor. The results suggest that F-19 chemical shift imaging of two PFCs, one coupled to antibody and the other not, has potential application in tumor diagnosis.
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Affiliation(s)
- H Mishima
- Second Department of Surgery, Osaka University Medical School, Japan
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33
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Mason RP, Nunnally RL, Antich PP. Tissue oxygenation: a novel determination using 19F surface coil NMR spectroscopy of sequestered perfluorocarbon emulsion. Magn Reson Med 1991; 18:71-9. [PMID: 2062243 DOI: 10.1002/mrm.1910180109] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This work examines the variation with oxygen tension (pO2) of the individual spin-lattice relaxation times (T1) of the 19F resonances of the perfluorocarbon emulsion Oxypherol-ET (FC-43). A linear relationship between 1/T1 and pO2 has been confirmed for all four resonances at any specific temperature. Using a saturation recovery sequence, T1 has been successfully measured using surface coil NMR spectroscopy. This has facilitated measurement of T1 in vivo in a subcutaneous murine tumor. Mice were predosed with Oxypherol-ET emulsion: following complete vascular clearance of the perfluorocarbon, 19F signal was observed specifically from material sequestered in tissue, thus avoiding flow artifacts. Comparison of the pO2 estimated from each of the 19F resonances provided an internal consistency check. A pO2 = 0.1 +/- 2.2% was determined in a Meth-A murine tumor. When the mouse breathed carbogen (95% O2, 5% CO2) no significant change in tumor pO2 was detected, whereas the pO2 in the liver showed a distinct increase.
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Affiliation(s)
- R P Mason
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas 75235
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34
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Visualisation of a fluorinated pharmaceutical formulation in the anaesthetised rat using 19F- and 1H-NMR imaging. Int J Pharm 1991. [DOI: 10.1016/0378-5173(91)90223-b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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35
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Abstract
The effect of homonuclear J modulation on 19F spin-echo images is evidenced by a substantial reduction in signal when the echo time, TE, approaches 1/2J, with a subsequent increase in signal at longer TEs. Suppression of the J-modulation effect is demonstrated using chemical shift-selective 180 degrees refocusing pulses.
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Affiliation(s)
- E E Babcock
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas 75235
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36
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Maxwell RJ, Frenkiel TA, Newell DR, Bauer C, Griffiths JR. 19F nuclear magnetic resonance imaging of drug distribution in vivo: the disposition of an antifolate anticancer drug in mice. Magn Reson Med 1991; 17:189-96. [PMID: 2067393 DOI: 10.1002/mrm.1910170122] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The application of 19F nuclear magnetic resonance imaging to the study of drug distribution in vivo is discussed. CB3988 (C2-desamino-C2-methyl-N10-propargyl-2'-trifluoromethyl-5,8-dideazafolic acid) is a fluorinated representative of a class of quinazoline antifolates which act as inhibitors of thymidylate synthase and which are being evaluated for the treatment of human cancer. 19F images were obtained in vivo from the abdomen of mice following intravenous injection of CB3988 (500 mg/kg). Time resolutions of 4 and 20 min were achieved for two- and three-dimensional imaging, respectively. These images were consistent with the presence of high concentrations of drug (up to 26 mg/ml) in the gall bladder, urinary bladder, and small intestine, as confirmed ex vivo by extraction and HPLC analysis. The results indicate the potential value of 19F NMR imaging in pharmacokinetic studies.
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Affiliation(s)
- R J Maxwell
- CRC Biomedical Magnetic Resonance Research Group, St. George's Hospital Medical School, London, United Kingdom
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37
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Kim SG, Ackerman JJ. Quantification of regional blood flow by monitoring of exogenous tracer via nuclear magnetic resonance spectroscopy. Magn Reson Med 1990; 14:266-82. [PMID: 2345507 DOI: 10.1002/mrm.1910140212] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Deuterium and fluorine nuclear magnetic resonance spectroscopy have been employed for quantification of regional blood flow in concert with nonradiative, exogenous, freely diffusible tracers such as D2O and freon gas. Typically, the tracer residue washout was monitored by NMR over time following tracer administration by bolus injection or inhalation. The theory, including compartmental analysis, required to quantitatively derive volumetric tissue blood flow and perfusion is reviewed herein. Applications of NMR tissue blood flow measurement techniques to tumor, muscle, liver, and brain are presented with discussion of the advantages and disadvantages of NMR methods.
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Affiliation(s)
- S G Kim
- Department of Chemistry, Washington University, St. Louis, Missouri 63130
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38
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Ceckler TL, Gibson SL, Hilf R, Bryant RG. In situ assessment of tumor vascularity using fluorine NMR imaging. Magn Reson Med 1990; 13:416-33. [PMID: 2325542 DOI: 10.1002/mrm.1910130309] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In situ fluorine NMR imaging has been used to measure vascularity in subcutaneously implanted mammary tumors. Oxyferol, a perfluorinated blood substitute comprised of an emulsion of 25% w/v perfluorotributylamine, was used as a tracer. Following iv administration, this perfluorocarbon emulsion remains primarily in the vasculature during the image acquisition period. The distribution of the PFTA in the 19F NMR image gives a map of tissue regions with intact vascularity. This technique has been used to demonstrate decreased blood flow in necrotic regions of R3230AC mammary tumors in which vasculature had been damaged either as a result of spontaneous necrosis or by photodynamic therapy (PDT). Damage to tumor vascularity following PDT was observed prior to the development of necrosis.
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Affiliation(s)
- T L Ceckler
- Department of Biophysics, University of Rochester School of Medicine, New York 14642
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39
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Young SW, Bradley B, Muller HH, Rubin DL. Detection of hepatic malignancies using Mn-DPDP (manganese dipyridoxal diphosphate) hepatobiliary MRI contrast agent. Magn Reson Imaging 1990; 8:267-76. [PMID: 2114511 DOI: 10.1016/0730-725x(90)90099-n] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A new hepatobiliary contrast agent (Mn-DPDP) was used in the detection of liver metastases in six rabbits with seven hepatic V2 carcinomas. This contrast agent is derived from pyridoxyl-5-phosphate which is biomimetically designed to be secreted by the hepatocyte. After Mn-DPDP administration, a 105% increase in liver signal to noise was obtained using a 200/20 (TR/TE) pulsing sequence, and a 62% decrease in intensity was observed using a 1200/60 pulsing sequence. Liver V2 carcinoma contrast enhancement increased 427% using the 200/20 pulsing sequence and 176% using the 1200/60 pulsing sequence. Four of seven V2 carcinomas were not detectable prior to the administration of Mn-DPDP (50 mumol/kg). Two neoplasms were only detectable in retrospect (after Mn-DPDP) on the 1200/60 sequence. The smallest neoplasms detected in this study were 1-4 mm. Mn-DPDP appears to be a promising MRI contrast agent.
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Affiliation(s)
- S W Young
- Department of Diagnostic Radiology, Stanford University School of Medicine, CA 94305
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40
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Mason RP, Antich PP, Babcock EE, Gerberich JL, Nunnally RL. Perfluorocarbon imaging in vivo: a 19F MRI study in tumor-bearing mice. Magn Reson Imaging 1989; 7:475-85. [PMID: 2607898 DOI: 10.1016/0730-725x(89)90402-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Multiresonance perfluorocarbon emulsions (Oxypherol and Fluosol-DA) were imaged in tumor-bearing mice using 19F spin-echo magnetic resonance imaging in vivo. Multiple thin-slice fluorine images free of chemical shift artifacts were obtained in 13 minutes and these were correlated with proton images obtained during the same experiment to delineate the anatomic distribution of perfluorocarbons. Sequential images were used to determine the time course of the distribution and the retention of the compounds in tumors and organs. 19F MR spectroscopy was used ex vivo to determine with high sensitivity the relative concentration of perfluorocarbons in different tissues and organs and to confirm the results obtained from imaging experiments. The fluorine images visually demonstrated the preferential localization of the perfluorocarbons in the liver and spleen; shortly after injection, the images also revealed the highly vascularized tumor-chest wall interface. Imaging and spectroscopy together showed that the perfluorocarbons were removed from the blood pool within hours and remained sequestered in tissues at later times; the highest concentrations were found in the spleen and liver, where the agents were retained without spectral changes for the duration of these studies. The perfluorocarbons accumulated within tumors at dose-dependent concentrations, one to two orders of magnitude smaller than those observed in the spleen and liver.
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Affiliation(s)
- R P Mason
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas 75235
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