Human whole‐blood relaxometry at 1.5T: Assessment of diffusion and exchange models

Human whole‐blood relaxometry experiments were performed to allow the prediction of blood signal changes with blood oxygen saturation (Y) and refocusing interval (τ180). Such predictions are particularly relevant for spin‐echo (SE) blood oxygenation level‐dependent (BOLD) experiments and a recently proposed noninvasive fMRI method for measuring cerebral blood volume (CBV). Ensemble fitting of the entire set of T2 estimates, obtained over an extensive range of Y and τ180 values, was performed with the use of both a fast chemical exchange model and a model of diffusion in weak magnetic field inhomogeneities. The diffusion modeling resulted in a large reduction in the residual sum‐of‐squares compared to the fast exchange modeling. The longitudinal relaxation rate decreased linearly with Y, and increased with hematocrit. The results support the application of the recently reported diffusion model to describe deoxyhemoglobin (dHb)‐induced blood transverse relaxation rate enhancement at 1.5 T. Magn Reson Med 52:716–723, 2004. © 2004 Wiley‐Liss, Inc.

[1]  E. Moser,et al.  Proton NMR relaxation times of human blood samples at 1.5 T and implications for functional MRI. , 1997, Cellular and molecular biology.

[2]  Risto A Kauppinen,et al.  Effects of hematocrit and oxygen saturation level on blood spin‐lattice relaxation , 2003, Magnetic resonance in medicine.

[3]  Xavier Golay,et al.  Measurement of tissue oxygen extraction ratios from venous blood T2: Increased precision and validation of principle , 2001, Magnetic resonance in medicine.

[4]  J. Bulte,et al.  Comparison of t2 relaxation in blood, brain, and ferritin , 1995, Journal of magnetic resonance imaging : JMRI.

[5]  C. Gasparovic,et al.  On the origin of paramagnetic inhomogeneity effects in whole blood , 1991, Magnetic resonance in medicine.

[6]  K. J. Packer.  The effects of diffusion through locally inhomogeneous magnetic fields on transverse nuclear spin relaxation in heterogeneous systems. Proton transverse relaxation in striated muscle tissue , 1973 .

[7]  R. Brooks,et al.  On T2‐shortening by weakly magnetized particles: The chemical exchange model † , 2001, Magnetic resonance in medicine.

[8]  Albert Macovski,et al.  Coronary Angiography with Magnetization‐Prepared T2 Contrast , 1995, Magnetic resonance in medicine.

[9]  J. A. Sanders,et al.  CHAPTER 7 – Functional Magnetic Resonance Imaging , 1995 .

[10]  R A Brooks,et al.  Magnetic resonance imaging of stationary blood: a review. , 1987, Medical physics.

[11]  Ray Freeman,et al.  Broadband Decoupling in High-Resolution Nuclear Magnetic Resonance Spectroscopy , 1984 .

[12]  D G Nishimura,et al.  Flow‐independent magnetic resonance projection angiography , 1991, Magnetic resonance in medicine.

[13]  G. Radda,et al.  Oxygenation dependence of the transverse relaxation time of water protons in whole blood at high field. , 1982, Biochimica et biophysica acta.

[14]  Risto A. Kauppinen,et al.  Quantitative assessment of blood flow, blood volume and blood oxygenation effects in functional magnetic resonance imaging , 1998, Nature Medicine.

[15]  G. Wright,et al.  Blood Relaxation Properties at 3T -- Effects of Blood Oxygen Saturation , 2003 .

[16]  J. Jensen,et al.  NMR relaxation in tissues with weak magnetic inhomogeneities , 2000, Magnetic resonance in medicine.

[17]  C. S. Poon,et al.  Practical T2 quantitation for clinical applications , 1992, Journal of magnetic resonance imaging : JMRI.

[18]  B. Meyer,et al.  Inhibitory and excitatory interhemispheric transfers between motor cortical areas in normal humans and patients with abnormalities of the corpus callosum. , 1995, Brain : a journal of neurology.

[19]  P W Kuchel,et al.  Application of spin-echo nuclear magnetic resonance to whole-cell systems. Membrane transport. , 1979, The Biochemical journal.

[20]  M. D. Herbst,et al.  A review of water diffusion measurement by NMR in human red blood cells. , 1989, The American journal of physiology.

[21]  T Asakura,et al.  NMR Relaxation Times of Blood: Dependence on Field Strength, Oxidation State, and Cell Integrity , 1987, Journal of computer assisted tomography.

[22]  C. Cuénod,et al.  Proton Transverse Nuclear Magnetic Relaxation in Oxidized Blood: a Numerical Approach , 1995, Magnetic resonance in medicine.

[23]  R. Bryant,et al.  Magnetic relaxation in blood and blood clots , 1990, Magnetic resonance in medicine.

[24]  D. Yablonskiy,et al.  Water proton MR properties of human blood at 1.5 Tesla: Magnetic susceptibility, T1, T2, T  *2 , and non‐Lorentzian signal behavior , 2001, Magnetic resonance in medicine.

[25]  T Conlon,et al.  Water diffusion permeability of erythrocytes using an NMR technique. , 1972, Biochimica et biophysica acta.

[26]  S. Meiboom,et al.  Nuclear Magnetic Resonance Study of the Protolysis of Trimethylammonium Ion in Aqueous Solution—Order of the Reaction with Respect to Solvent , 1963 .

[27]  R. Henkelman,et al.  Practical Implementation and Optimization of One‐shot T1 imaging , 1991, Magnetic resonance in medicine.

[28]  R. Weisskoff,et al.  MRI susceptometry: Image‐based measurement of absolute susceptibility of MR contrast agents and human blood , 1992, Magnetic resonance in medicine.

[29]  Charles Gasparovic,et al.  On the origin of paramagnetic inhomogeneity effects in blood , 1989, Magnetic resonance in medicine.

[30]  R. Bryant,et al.  Noninvasive measurement of protein concentration , 1996, Magnetic resonance in medicine.

[31]  C. Gasparovic,et al.  The line shapes of the water proton resonances of red blood cells containing carbonyl hemoglobin, deoxyhemoglobin, and methemoglobin: implications for the interpretation of proton MRI at fields of 1.5 T and below. , 1990, Magnetic resonance imaging.

[32]  D. Altman,et al.  STATISTICAL METHODS FOR ASSESSING AGREEMENT BETWEEN TWO METHODS OF CLINICAL MEASUREMENT , 1986, The Lancet.

[33]  X Golay,et al.  Comparison of the dependence of blood R2 and R  2* on oxygen saturation at 1.5 and 4.7 Tesla , 2003, Magnetic resonance in medicine.

[34]  S. H. Koenig,et al.  Transverse relaxation of solvent protons induced by magnetized spheres: Application to ferritin, erythrocytes, and magnetite , 1987, Magnetic resonance in medicine.

[35]  Charles Gasparovic,et al.  The magnetic properties and water dynamics of the red blood cell: A study by proton‐NMR lineshape analysis , 1992, Magnetic resonance in medicine.