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Duyn J. MR susceptibility imaging. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 229:198-207. [PMID: 23273840 PMCID: PMC3602381 DOI: 10.1016/j.jmr.2012.11.013] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 05/23/2023]
Abstract
This work reviews recent developments in the use of magnetic susceptibility contrast for human MRI, with a focus on the study of brain anatomy. The increase in susceptibility contrast with modern high field scanners has led to novel applications and insights into the sources and mechanism contributing to this contrast in brain tissues. Dedicated experiments have demonstrated that in most of healthy brain, iron and myelin dominate tissue susceptibility variations, although their relative contribution varies substantially. Local variations in these compounds can affect both amplitude and frequency of the MRI signal. In white matter, the myelin sheath introduces an anisotropic susceptibility that has distinct effects on the water compartments inside the axons, between the myelin sheath, and the axonal space, and renders their signals dependent on the angle between the axon and the magnetic field. This offers opportunities to derive tissue properties specific to these cellular compartments.
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Affiliation(s)
- Jeff Duyn
- Advanced MRI Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
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Vinogradov E, Soesbe TC, Balschi JA, Sherry AD, Lenkinski RE. pCEST: Positive contrast using Chemical Exchange Saturation Transfer. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 215:64-73. [PMID: 22237630 PMCID: PMC3288637 DOI: 10.1016/j.jmr.2011.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 12/13/2011] [Accepted: 12/14/2011] [Indexed: 05/11/2023]
Abstract
Chemical Exchange Saturation Transfer (CEST) contrast utilizes selective pre-saturation of a small pool of exchanging protons and subsequent detection of the decrease in bulk water signal. The CEST contrast is negative and requires detection of small signal change in the presence of a strong background signal. Here we develop a Positive CEST (pCEST) detection scheme utilizing the analogous nature of the CEST and off-resonance T(1)(ρ) experiments and exploring increased apparent relaxation rates in the presence of the selective pre-saturation. pCEST leads to the positive contrast, i.e., increased signal intensity as the result of the presence of the agent and RF pre-saturation. Simultaneously substantial background suppression is achieved. The contrast can be switched "ON" and "OFF", similar to the original CEST.
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Affiliation(s)
- Elena Vinogradov
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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Norek M, Peters JA. MRI contrast agents based on dysprosium or holmium. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2011; 59:64-82. [PMID: 21600356 DOI: 10.1016/j.pnmrs.2010.08.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 08/31/2010] [Indexed: 05/30/2023]
Affiliation(s)
- Małgorzata Norek
- Biocatalysis and Organic Chemistry, Department of Biotechnology, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands
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Bakker CJG, de Leeuw H, Vincken KL, Vonken EJ, Hendrikse J. Phase gradient mapping as an aid in the analysis of object-induced and system-related phase perturbations in MRI. Phys Med Biol 2008; 53:N349-58. [PMID: 18723928 DOI: 10.1088/0031-9155/53/18/n02] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In this note we wish to demonstrate the utility of phase gradient mapping (PGM) as an aid in the analysis and characterization of object-induced and system-related macroscopic phase perturbations in MRI. To achieve this goal, phase gradient maps and, if applicable, field gradient maps were derived from standard phase images via a forward difference operator taking into account phase wraps. By way of phantom experiments, PGM was shown to provide reliable phase and field gradient information, even in regions with multiple phase wraps. Phase gradient mapping was further shown to allow positive identification of local phase and field perturbations and global discrimination between positive and negative local susceptibility deviations. The suitability of PGM for in vivo studies was demonstrated by a 3D brain examination of a healthy volunteer.
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Affiliation(s)
- Chris J G Bakker
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, The Netherlands.
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Liu W, Dahnke H, Jordan EK, Schaeffter T, Frank JA. In vivo MRI using positive-contrast techniques in detection of cells labeled with superparamagnetic iron oxide nanoparticles. NMR IN BIOMEDICINE 2008; 21:242-50. [PMID: 17566968 DOI: 10.1002/nbm.1187] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Positive-contrast techniques are being developed to increase the detection of magnetically labeled cells in tissues. We evaluated a post-processing positive-contrast technique, susceptibility-gradient mapping (SGM), and compared this approach with two pulse sequences, a gradient-compensation-based "White Marker" technique and an off-resonance-based approach, inversion recovery on-resonance water suppression (IRON), for the detection of superparamagnetic iron oxide (SPIO) nanoparticle-labeled C6 glioma cells implanted in the flanks of nude rats. The SGM, White Marker and IRON positive-contrast images were acquired when the labeled C6 glioma tumors were approximately 5 mm (small), approximately 10 mm (medium) and approximately 20 mm (large) in diameter along the largest dimension to evaluate their sensitivity to the dilution of the SPIO nanoparticles as the tumor cells proliferated. In vivo MRI demonstrated that all three positive-contrast techniques can produce hyperintensities in areas around the labeled flank tumors against a dark background. The number of positive voxels detected around small and medium tumors was significantly greater with the SGM technique than with the White Marker and IRON techniques. For large tumors, the SGM resulted in a similar number of positive voxels to the White Marker technique, and the IRON approach failed to generate positive-contrast images with a 200 Hz suppression band. This study also reveals that hemorrhage appears as hyperintensities on positive-contrast images and may interfere with the detection of SPIO-labeled cells.
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Affiliation(s)
- Wei Liu
- Philips Research Laboratories, Briarcliff Manor, NY 10510, USA.
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Ribot EJ, Thiaudière E, Roulland R, Brugières P, Rahmouni A, Voisin P, Franconi JM, Miraux S. Application of MRI phase-difference mapping to assessment of vascular concentrations of BMS agent in mice. CONTRAST MEDIA & MOLECULAR IMAGING 2008; 3:53-60. [DOI: 10.1002/cmmi.230] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Seppenwoolde JH, Vincken KL, Bakker CJG. White-marker imaging—Separating magnetic susceptibility effects from partial volume effects. Magn Reson Med 2007; 58:605-9. [PMID: 17628486 DOI: 10.1002/mrm.21304] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
By applying dephasing gradients, local magnetic field inhomogeneitiescan selectively visualized with positive contrast, such as those created by magnetically labeled cells. This is known as "white-marker imaging." In white-marker imaging, subvoxel signal variations are also visualized as a result of partial volume (PV) effects and may compromise the identification of magnetic structures (e.g., magnetically-labeled cells). This study presents the theory and proof-of-principle experiments of a strategy to eliminate PV effects during white-marker imaging. The strategy employs the asymmetry of the signal response curves for non-PV effects as a function of externally applied gradients. In the case of PV effects, subtraction of the symmetrical signal responses eliminates their contribution. In vitro experimental images were made using a spherical phantom with cylindrical elements. In vivo images of the brain were obtained at a location that included air cavities (susceptibility effects) and the circle of Willis (PV effect). The results show that PV effects were eliminated in the in vitro experiments and were virtually absent under in vivo conditions.
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Affiliation(s)
- Jan-Henry Seppenwoolde
- Image Sciences Institute, University Medical Center Utrecht, Department of Radiology, The Netherlands.
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Haacke EM, Cheng NYC, House MJ, Liu Q, Neelavalli J, Ogg RJ, Khan A, Ayaz M, Kirsch W, Obenaus A. Imaging iron stores in the brain using magnetic resonance imaging. Magn Reson Imaging 2005; 23:1-25. [PMID: 15733784 DOI: 10.1016/j.mri.2004.10.001] [Citation(s) in RCA: 725] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Accepted: 10/07/2004] [Indexed: 02/06/2023]
Abstract
For the last century, there has been great physiological interest in brain iron and its role in brain function and disease. It is well known that iron accumulates in the brain for people with Huntington's disease, Parkinson's disease, Alzheimer's disease, multiple sclerosis, chronic hemorrhage, cerebral infarction, anemia, thalassemia, hemochromatosis, Hallervorden-Spatz, Down syndrome, AIDS and in the eye for people with macular degeneration. Measuring the amount of nonheme iron in the body may well lead to not only a better understanding of the disease progression but an ability to predict outcome. As there are many forms of iron in the brain, separating them and quantifying each type have been a major challenge. In this review, we present our understanding of attempts to measure brain iron and the potential of doing so with magnetic resonance imaging. Specifically, we examine the response of the magnetic resonance visible iron in tissue that produces signal changes in both magnitude and phase images. These images seem to correlate with brain iron content, perhaps ferritin specifically, but still have not been successfully exploited to accurately and precisely quantify brain iron. For future quantitative studies of iron content we propose four methods: correlating R2' and phase to iron content; applying a special filter to the phase to obtain a susceptibility map; using complex analysis to extract the product of susceptibility and volume content of the susceptibility source; and using early and late echo information to separately predict susceptibility and volume content.
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Affiliation(s)
- E Mark Haacke
- The MRI Institute for Biomedical Research, 440 East Ferry Street, Detroit, MI 48202, USA.
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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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Du W, Du YP, Bick U, Fan X, MacEneaney PM, Zamora MA, Medved M, Karczmar GS. Breast MR imaging with high spectral and spatial resolutions: preliminary experience. Radiology 2002; 224:577-85. [PMID: 12147859 DOI: 10.1148/radiol.2242011022] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The authors evaluated magnetic resonance (MR) imaging with high spectral and spatial resolutions (HSSR) of water and fat in breasts of healthy volunteers (n = 6) and women with suspicious lesions (n = 6). Fat suppression, edge delineation, and image texture were improved on MR images derived from HSSR data compared with those on conventional MR images. HSSR MR imaging data acquired before and after contrast medium injection showed spectrally inhomogeneous changes in the water resonances in small voxels that were not detectable with conventional MR imaging.
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Affiliation(s)
- Weiliang Du
- Department of Radiology, MC2026, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637, USA
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Al-Hallaq HA, Fan X, Zamora M, River JN, Moulder JE, Karczmar GS. Spectrally inhomogeneous BOLD contrast changes detected in rodent tumors with high spectral and spatial resolution MRI. NMR IN BIOMEDICINE 2002; 15:28-36. [PMID: 11840550 DOI: 10.1002/nbm.728] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
MRI detects changes in blood-oxygenation-level dependent (BOLD) contrast in tumors caused by tumor oxygenating agents. These changes can be used to guide the design of improved tumor oxygenating treatments (TOXs). The conventional approach to detection of BOLD effects assumes that the water resonance is a single, homogeneously broadened Lorentzian line, and that changes in the T2* of this line owing to changes in deoxyhemoglobin are spectrally homogeneous. This model may not adequately describe BOLD contrast changes in complex water resonances that are often detected in tumors. The present work investigated: (a) whether changes in the water resonance in very small voxels caused by tumor oxygenating agents are spectrally inhomogeneous; and (b) whether high spectral and spatial resolution (HiSS) MRI of the water and fat resonances detects these changes more accurately than conventional gradient-recalled echo (GRE) imaging. Carbogen (95% oxygen, 5% CO2) was used to increase tumor oxygenation. In two tumor models [mammary adenocarcinoma (R3230Ac; n=5) and rhabdomyosarcoma (BA1112; n=5)] proton signals were often complex and inhomogeneously broadened. Spectrally inhomogeneous changes during carbogen breathing occurred in at least 10% of the R3230AC tumor voxels that responded to carbogen and 18% of BA1112 tumor voxels. The largest changes during carbogen breathing in many voxels occurred at frequencies that were significantly different from the frequency of the primary water peak. Carbogen-induced changes in proton T2* detected by simulated GRE and HiSS differed by more than 75% in 67% of voxels in R3230Ac tumors and in 65% of voxels in BA1112 tumors. The spectrally inhomogeneous effects of tumor oxygenating agents may reflect changes in sub-voxelar microenvironements and thus may be important for accurate evaluation of the effects of therapy.
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Affiliation(s)
- Hania A Al-Hallaq
- Department of Radiology, The University of Chicago, Chicago, IL 60637, USA
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Zhong K, Li X, Shachar-Hill Y, Picart F, Wishnia A, Springer CS. Magnetic susceptibility shift selected imaging (MESSI) and localized (1)H(2)O spectroscopy in living plant tissues. NMR IN BIOMEDICINE 2000; 13:392-397. [PMID: 11114062 DOI: 10.1002/1099-1492(200011)13:7<392::aid-nbm659>3.0.co;2-o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Maize root segments permeated with aqueous solutions of the paramagnetic agents GdDTPA(2-) or DyDTPA-BMA display two well-resolved NMR peaks corresponding to the signals from intracellular and extracellular (1)H(2)O, which arise from well-understood bulk magnetic susceptibility effects. This allows each component to be studied separately. Images obtained at each frequency with MESSI editing, and single- and multiple-voxel ('spectroscopic imaging') localized spectra, clearly indicate that the agents permeate into the interstitial spaces, and into the longitudinal (xylem/phloem) channels in the stele (core) of the root, confirming earlier assessments. We believe these are the first images of a multicellular tissue acquired in vivo exclusively from the intracellular water proton resonance. This method can be further exploited to study water transport in similar systems.
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Affiliation(s)
- K Zhong
- Department of Chemistry, SUNY Stony Brook, NY 11794-3400, USA
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Fossheim S, Johansson C, Fahlvik AK, Grace D, Klaveness J. Lanthanide-based susceptibility contrast agents: assessment of the magnetic properties. Magn Reson Med 1996; 35:201-6. [PMID: 8622584 DOI: 10.1002/mrm.1910350211] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The T2* contrast efficacy of paramagnetic contrast agents is dependent on their magnetic properties. Vibrating sample magnetometry (VSM) and the Live Chan NMR method have been used to evaluate the influence of ligand structure on the bulk magnetic susceptibility (BMS) of low-molecular weight (LMW) lanthanide chelates. VSM was also used for the BMS assessment of LMW lanthanide chelates covalently attached to cross-linked starch particles. The ligand structure had no influence on the BMS of the gadolinium (Gd) and dysprosium (Dy) chelates. The mean BMS value of the Dy-chelates was 1.8 fold higher than that of the Gd-chelates. The holmium (Ho) DTPA-BMA chelate had a similar BMS to that of Dy-DTPA-BMA while the lowest BMS was found for europium (Eu(III)) DTPA-BMA. The covalent attachment of Gd-DTPA and Dy-DTPA to a cross-linked starch particle had no impact on their intrinsic magnetic properties. The BMS data were in good accordance with those obtained for non-particulate bound LMW Dy- and Gd-chelates. The magnetic susceptibility of the Gd-DTPA labeled particles was described by the Curie law, indicative of no magnetic interactions between Gd-DTPA molecules. The magnetic susceptibility of the Dy-DTPA labeled particles followed the Curie-Weiss law with a Curie-Weiss temperature of about-2 K, indicating magnetic interactions. The magnetic susceptibility of Dy-DTPA will, however, not be affected by such magnetic interactions at physiological temperatures.
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Affiliation(s)
- S Fossheim
- Department of Medicinal Chemistry, School of Pharmacy, University of Oslo, Norway
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Bacić G, Liu KJ, O'Hara JA, Harris RD, Szybinski K, Goda F, Swartz HM. Oxygen tension in a murine tumor: a combined EPR and MRI study. Magn Reson Med 1993; 30:568-72. [PMID: 8259056 DOI: 10.1002/mrm.1910300507] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The effects of fusinite, a new agent for the measurement of the concentration of oxygen in vivo by EPR, on MRI images have been studied. There was little effect on spin-echo T1-weighted images, but the fusinite resulted in large effects on T2-weighted images. Especially large effects could be observed when using spoiled gradient echo sequences (SPGR). The observed measurements of oxygen by EPR corresponded to the relative vascularity at the site of the fusinite both histologically and by MRI studies of vascularity using Gd-DTPA as a contrast agent. We conclude that by using the effects of fusinite on magnetic susceptibility, it can be located accurately and noninvasively with MRI and thereby the value of the use of fusinite to measure concentration of oxygen in vivo is enhanced.
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Affiliation(s)
- G Bacić
- Department of Radiology, Dartmouth Medical School, Hanover, New Hampshire 03755
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Albert MS, Huang W, Lee JH, Balschi JA, Springer CS. Aqueous shift reagents for high-resolution cation NMR. VI. Titration curves for in vivo 23Na and 1H2O MRS obtained from rat blood. NMR IN BIOMEDICINE 1993; 6:7-20. [PMID: 8457429 DOI: 10.1002/nbm.1940060103] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Frequency shift/concentration calibration curves applicable to the use of shift reagents (SRs) for in vivo 23Na MRS studies can be obtained from experiments with whole blood. Here, they are reported for titrations of rat blood with the SRs DyTTHA3- and TmDOTP5-. There are a number of considerations that must be made in order to derive accurate calibration curves from the experimental data. These include the effects of bulk magnetic susceptibility (BMS, since the SRs are paramagnetic), the effects of water flux (since addition of the SR stock solution to blood renders the plasma hyperosmotic), and the consequences of restricted distribution of the SR anion in the erythrocyte suspension. We give in some detail the BMS shift theory that obtains in this case and show also how it applies to excised perfused organ as well as in vivo studies. Also, we report significant effects of adjuvant Ca2+ additions in the TmDOTP5- titrations. These are very important to the successful use of this SR in vivo. Finally, our considerations of BMS lead naturally to an understanding of its manifestations in the shifts of the 1H2O resonance frequencies of cell suspensions and tissues induced by SRs. Since these are being increasingly reported, and often misinterpreted, we devote an experiment and some discussion to this subject. We show that this phenomenon cannot be used to quantitatively discriminate intra- and extracellular 1H2O signals.
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Affiliation(s)
- M S Albert
- Department of Chemistry, State University of New York, Stony Brook 11794-3400
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Mosher TJ, Smith MB. Magnetic susceptibility measurement using a double-DANTE tagging (DDT) sequence. Magn Reson Med 1991; 18:251-5. [PMID: 2062238 DOI: 10.1002/mrm.1910180127] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Preliminary results are presented for the nuclear magnetic resonance (NMR) measurement of field gradients generated by differences in magnetic susceptibility. The DDT technique maps the resonant frequency throughout the sample in a single image. Regions of paramagnetic and diamagnetic susceptibility are differentiated with a single magnitude-calculated image.
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Affiliation(s)
- T J Mosher
- Department of Radiology, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey 17033
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