The MT pool size ratio and the DTI radial diffusivity may reflect the myelination in shiverer and control mice

A quantitative magnetization transfer (qMT) technique was employed to quantify the ratio of the sizes of the bound and free water proton pools in ex vivo mouse brains. The goal was to determine the pool size ratio sensitivity to myelin. Fixed brains from both shiverer mice and control littermates were imaged. The pool size ratio in the corpus callosum of shiverer mice was substantially lower than that in the control mice, while there was no distinguishable difference in the pool size ratio in the gray matter. These results correlate with diffusion tensor imaging (DTI) derived radial diffusivity which previously was shown to reflect myelin integrity in this animal model. Histological study reveals the presence of myelin in control mice white matter and the absence of myelin in shiverer mice white matter, supporting the qMT and DTI results. Our findings support the view that qMT may be used for estimating myelin integrity. Copyright © 2008 John Wiley & Sons, Ltd.

[1]  Shu-Wei Sun,et al.  Differential sensitivity of in vivo and ex vivo diffusion tensor imaging to evolving optic nerve injury in mice with retinal ischemia , 2006, NeuroImage.

[2]  P. Basser,et al.  Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI. , 1996, Journal of magnetic resonance. Series B.

[3]  C. Laule,et al.  Water content and myelin water fraction in multiple sclerosis , 2004, Journal of Neurology.

[4]  David H. Miller,et al.  Apparent diffusion coefficients in benign and secondary progressive multiple sclerosis by nuclear magnetic resonance , 1996, Magnetic resonance in medicine.

[5]  N. Lundbom,et al.  Relaxometry of brain: Why white matter appears bright in MRI , 1990, Magnetic resonance in medicine.

[6]  David H. Miller,et al.  Quantitative magnetic resonance of postmortem multiple sclerosis brain before and after fixation , 2008, Magnetic resonance in medicine.

[7]  N. Baumann,et al.  Absence of the major dense line in myelin of the mutant mouse ‘shiverer’ , 1979, Neuroscience Letters.

[8]  S. Blackband,et al.  Effects of temperature and aldehyde fixation on tissue water diffusion properties, studied in an erythrocyte ghost tissue model , 2006, Magnetic resonance in medicine.

[9]  R E Lenkinski,et al.  Magnetization transfer imaging and proton MR spectroscopy in the evaluation of axonal injury: correlation with clinical outcome after traumatic brain injury. , 2001, AJNR. American journal of neuroradiology.

[10]  I Levesque,et al.  Regional variations in normal brain shown by quantitative magnetization transfer imaging , 2004, Magnetic resonance in medicine.

[11]  R E Snyder,et al.  Multiexponential T2 relaxation in degenerating peripheral nerve , 1996, Magnetic resonance in medicine.

[12]  Yasuzo Tsukada,et al.  Fine structure of the central myelin sheath in the myelin deficient mutant Shiverer mouse, with special reference to the pattern of myelin formation by oligodendroglia , 1981, Brain Research.

[13]  Hsiao-Fang Liang,et al.  Detecting axon damage in spinal cord from a mouse model of multiple sclerosis , 2006, Neurobiology of Disease.

[14]  Shu-Wei Sun,et al.  Diffusion tensor imaging detects and differentiates axon and myelin degeneration in mouse optic nerve after retinal ischemia , 2003, NeuroImage.

[15]  B. Trapp,et al.  Pathogenesis of tissue injury in MS lesions , 1999, Journal of Neuroimmunology.

[16]  Derek K Jones,et al.  Applications of diffusion‐weighted and diffusion tensor MRI to white matter diseases – a review , 2002, NMR in biomedicine.

[17]  A. MacKay,et al.  In vivo visualization of myelin water in brain by magnetic resonance , 1994, Magnetic resonance in medicine.

[18]  J. Gore,et al.  Quantitative imaging of magnetization transfer using an inversion recovery sequence , 2003, Magnetic resonance in medicine.

[19]  Jean-Marie Bonny,et al.  In vivo analysis of the post‐natal development of normal mouse brain by DTI , 2007, NMR in biomedicine.

[20]  C. Beaulieu,et al.  Multi-component T1 relaxation and magnetisation transfer in peripheral nerve. , 1998, Magnetic resonance imaging.

[21]  G. B. Pike,et al.  Quantitative imaging of magnetization transfer exchange and relaxation properties in vivo using MRI , 2001, Magnetic resonance in medicine.

[22]  Rajiv Midha,et al.  MR properties of excised neural tissue following experimentally induced demyelination , 2005, NMR in biomedicine.

[23]  Rajiv Midha,et al.  MR properties of excised neural tissue following experimentally induced inflammation , 2004, Magnetic resonance in medicine.

[24]  L Steinman,et al.  Multiple Sclerosis: A Coordinated Immunological Attack against Myelin in the Central Nervous System , 1996, Cell.

[25]  Sheng-Kwei Song,et al.  Relative indices of water diffusion anisotropy are equivalent in live and formalin‐fixed mouse brains , 2003, Magnetic resonance in medicine.

[26]  J C Gore,et al.  Quantitative imaging of magnetization transfer using multiple selective pulses , 1999, Magnetic resonance in medicine.

[27]  R M Henkelman,et al.  Quantitative interpretation of magnetization transfer , 1993, Magnetic resonance in medicine.

[28]  B K Rutt,et al.  Magnetization transfer and multicomponent T2 relaxation measurements with histopathologic correlation in an experimental model of MS , 2000, Journal of magnetic resonance imaging : JMRI.

[29]  John Russell,et al.  Dysmyelination Revealed through MRI as Increased Radial (but Unchanged Axial) Diffusion of Water , 2002, NeuroImage.

[30]  Jun Yoshino,et al.  Demyelination increases radial diffusivity in corpus callosum of mouse brain , 2005, NeuroImage.

[31]  J. Gore,et al.  Quantitative studies of magnetization transfer by selective excitation and T1 recovery , 1997, Magnetic resonance in medicine.

[32]  M Cercignani,et al.  Diffusion tensor magnetic resonance imaging in multiple sclerosis , 2001, Neurology.

[33]  G. Pike,et al.  Quantitative interpretation of magnetization transfer in spoiled gradient echo MRI sequences. , 2000, Journal of magnetic resonance.

[34]  R M Henkelman,et al.  A multicenter measurement of magnetization transfer ratio in normal white matter. , 2000, Journal of Magnetic Resonance Imaging.

[35]  K. Nave,et al.  Axonal swellings and degeneration in mice lacking the major proteolipid of myelin. , 1998, Science.

[36]  M. Bronskill,et al.  Characterizing white matter with magnetization transfer and T2 , 1999, Magnetic resonance in medicine.

[37]  S. Reingold,et al.  The role of magnetic resonance techniques in understanding and managing multiple sclerosis. , 1998, Brain : a journal of neurology.

[38]  Christian Enzinger,et al.  Method for quantitative imaging of the macromolecular 1H fraction in tissues , 2003, Magnetic resonance in medicine.

[39]  G. Barker,et al.  Precise estimate of fundamental in-vivo MT parameters in human brain in clinically feasible times. , 2002, Magnetic resonance imaging.

[40]  G J Barker,et al.  Quantitative magnetization transfer mapping of bound protons in multiple sclerosis , 2003, Magnetic resonance in medicine.

[41]  Sharon Portnoy,et al.  Modeling pulsed magnetization transfer , 2007, Magnetic resonance in medicine.

[42]  Vasily L Yarnykh,et al.  Pulsed Z‐spectroscopic imaging of cross‐relaxation parameters in tissues for human MRI: Theory and clinical applications , 2002, Magnetic resonance in medicine.

[43]  Jens Frahm,et al.  Multicontrast MRI of remyelination in the central nervous system , 2005, NMR in biomedicine.

[44]  P S Tofts,et al.  Correlation of apparent myelin measures obtained in multiple sclerosis patients and controls from magnetization transfer and multicompartmental T2 analysis , 2005, Magnetic resonance in medicine.

[45]  John C Gore,et al.  Quantitative magnetization transfer imaging via selective inversion recovery with short repetition times , 2007, Magnetic resonance in medicine.

[46]  S. H. Koenig,et al.  Cholesterol of myelin is the determinant of gray‐white contrast in MRI of brain , 1991, Magnetic resonance in medicine.