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In this thesis methods for the assessment of cerebral haemodynamics using 7 T Magnetic Resonance Imaging (MRI) are described. The measurement of haemodynamic parameters, such as cerebral blood flow (CBF), is an important clinical tool. Arterial Spin Labelling (ASL) is a non-invasive technique for CBF measurement using MRI. ASL methodology for ultra high field (7 T) MRI was developed, including investigation of the optimal readout strategy. Look-Locker 3D-EPI is demonstrated to give large volume coverage improving on previous studies. Applications of methods developed to monitor functional activity, through flow or arterial blood volume, in healthy volunteers and in patients with low grade gliomas using Look-Locker ASL are described. The effect of an increased level of carbon dioxide in the blood (hypercapnia) was studied using ASL and functional MRI; hypercapnia is a potent vasodilator and has a large impact on haemodynamics. These measures were used to estimate the increase in oxygen metabolism associated with a simple motor task. To study the physiology behind the hypercapnic response, magnetoencephalography was used to measure the impact of hypercapnia on neuronal activity. It was shown that hypercapnia induces widespread desynchronisation in a wide frequency range, up to ~ 50 Hz, with peaks in the sensory-motor areas. This suggests that hypercapnia is not iso-metabolic, which is an assumption of calibrated BOLD. A Look-Locker gradient echo sequence is described for the quantitative monitoring of a gadolinium contrast agent uptake through the change in longitudinal relaxation rate. This sequence was used to measure cerebral blood volume in Multiple Sclerosis patients. Further development of the sequence yielded a high resolution anatomical scan with reduced artefacts due to field inhomogeneities associated with ultra high field imaging. This allows whole head images acquired at sub-millimetre resolution in a short scan time, for application in patient studies.
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    • Lauterbur, P., Image Formation by Induced Local Interactions: Examples Employing Nuclear Magnetic Resonance. Nature, 1973. 242: p. 190-191.
    • Garroway, A.N., P.K. Grannell, and P. Mansfield, Image Formation in NMR by a Selective Irradiative Process. J. Phys. C: Solid State Phys., 1974. 7: p. 457-462.
    • 2010, Cambridge: Cambridge University Press.
    • Blamire, A.M., The technology of MRI - the next 10 years? The British Journal of Radiology, 2008. 81: p. 601-617.
    • Merkle, R. Goebel, M.B. Smith, and K. Ugurbil, 7T vs. 4T: RF power, homogeneity, and signalto-noise comparison in head images. Magnetic Resonance in Medicine, 2001. 46(1): p. 24- 30.
    • Vaughan, H. Merkle, K. Ugurbil, and X. Hu, Imaging brain function in humans at 7 Tesla.
    • Magnetic Resonance in Medicine, 2001. 45(4): p. 588-594.
    • Pfeuffer, J., G. Adriany, A. Shmuel, E. Yacoub, P.-F. Van De Moortele, X. Hu, and K. Ugurbil, Perfusion-based high-resolution functional imaging in the human brain at 7 Tesla. Magnetic Resonance in Medicine, 2002. 47(5): p. 903-911.
    • Gardener, A.G., P.A. Gowland, and S.T. Francis, Implementation of Quantitative Perfusion Imaging Using Pulsed Arterial Spin Labeling at Ultra-High Field. Mag. Res. Med., 2009. 61: p. 874-882.
    • Turner, Diffusion imaging in humans at 7T using readout-segmented EPI and GRAPPA.
    • Magnetic Resonance in Medicine. 64(1): p. 9-14.
    • Rooney, W.D., G. Johnson, X. Li, E.R. Cohen, S.-G. Kim, K. Ugurbil, and C.S. Springer, Magnetic Field and Tissue Dependancies of Human Brain Longitudinal 1H2O Relaxation in Vivo. Mag. Res. Med., 2007. 57: p. 308-318.
    • Clemence, S.T. Francis, R. Bowtell, and P.A. Gowland, Water Proton T1 Measurements in Brain Tissue at 7, 3 and 1.5T using IR-EPI, IR-TSE and MPRAGE: results and optimisation.
    • Magn. Reson. Mater. Phy, 2008. 21: p. 121-130.
    • Bowtell, T2* Measurements in Human Brain at 1.5, 3 and 7T. Magnetic Resonance Imaging, 2007. 25: p. 748 - 753.
    • Cox, E.F. and P. Gowland, Simultaneous Quantification of T2 and T2' Using a Combined Gradient Echo-Spin Echo Sequence at Ultrahigh Field. Mag. Res. Med., 2010. 64: p. 1441- 1446.
    • Forsting, and I. Wanke, First Clinical Study on Ultra-High-Field MR Imaging in Patients with Multiple Sclerosis: Comparison of 1.5T and 7T. American Journal of Neuroradiology, 2009.
    • 30(4): p. 699-702.
    • Regatte, R.R. and M.E. Schweitzer, Ultra-high-field MRI of the musculoskeletal system at 7.0T. Journal of Magnetic Resonance Imaging, 2007. 25(2): p. 262-269.
    • Andersen, J. Strupp, and K. Ugurbil, Whole-body imaging at 7T: Preliminary results.
    • Magnetic Resonance in Medicine, 2009. 61(1): p. 244-248.
    • Behr, B.r., J.r. Stadler, H. Michaely, H.-G. Damert, and W. Schneider, MR imaging of the human hand and wrist at 7Â T. Skeletal Radiology, 2009. 38(9): p. 911-917.
    • Vaughan, Initial results of cardiac imaging at 7 tesla. Magnetic Resonance in Medicine, 2009. 61(3): p. 517-524.
    • Umutlu, L., S. Orzada, S. Kinner, S. Maderwald, I. Brote, A. Bitz, O. Kraff, S. Ladd, G. Antoch, M. Ladd, H. Quick, and T. Lauenstein, Renal imaging at 7 Tesla: preliminary results.
    • European Radiology. 21(4): p. 841-849.
    • Rev. Sci. Instrum., 1970. 41: p. 250-1.
    • Rooney, W.D., G. Johnson, X. Li, E.R. Cohen, S.-G. Kim, K. Ugurbil, and C.S. Springer, Magnetic Field and Tissue Dependancies of Human Brain Longitudinal 1H2O Relaxation in Vivo. Mag. Res. Med., 2007. 57: p. 308-318.
    • Clemence, S.T. Francis, R. Bowtell, and P.A. Gowland, Water Proton T1 Measurements in Brain Tissue at 7, 3 and 1.5T using IR-EPI, IR-TSE and MPRAGE: results and optimisation.
    • Magn. Reson. Mater. Phy, 2008. 21: p. 121-130.
    • Rev. Sci. Instrum., 1970. 41: p. 250-1.
    • Kaptein, R., K. Dijkstra, and C.E. Tarr, Single-Scan Fourier Transform Method for Measuring Spin-Lattice Relaxation Times. Journal of Magnetic Resonance, 1976. 24(2): p. 295-300.
    • Young, I.R., A.S. Hall, and G.M. Bydder, The design of a multiple inversion recovery sequence for T1 measurement. Magnetic Resonance in Medicine, 1987. 5(2): p. 99-108.
    • Brix, G., L.R. Schad, M. Deimling, and W.J. Lorenz, Fast and Precise T1 Imaging Using a TOMROP Sequence. Magnetic Resonance Imaging, 1990. 8: p. 351-356.
    • Kay, I. and R.M. Henkelman, Practical Implementation and Optimization of One-shot T1 imaging. Magnetic Resonance in Medicine, 1991. 22(2): p. 414-424.
    • Deichmann, R. and A. Haase, Quantification Of T1 Values By Snapshot-FLASH NMR Imaging.
    • Journal of Magnetic Resonance, 1992. 96(3): p. 608-612.
    • Gowland, P. and P. Mansfield, Accurate Measurement Of T(1) In-Vivo In Less Than 3 Seconds Using Echo-Planar Imaging. Magnetic Resonance in Medicine, 1993. 30(3): p. 351-354.
    • Deichmann, R., Fast high-resolution T1 mapping of the human brain. Magnetic Resonance in Medicine, 2005. 54(1): p. 20-27.
    • Shah, N.J., M. Zaitsev, S. Steinhoff, and K. Zilles, A new method for fast multislice T-1 mapping. Neuroimage, 2001. 14(5): p. 1175-1185.
    • Chikui, T., K. Tokumori, R. Zeze, T. Shiraishi, T. Ichihara, M. Hatakenaka, and K. Yoshiura, A fast Look-Locker method for T1 mapping of the head and neck region. Oral. Radiol., 2009.
    • 25: p. 22-29.
    • McKenzie, C.A., R.S. Pereira, F.S. Prato, Z. Chen, and D.J. Crost, Improved contrast agent bolus tracking using T1 FARM. Mag. Res. Med., 1999. 41: p. 429-435.
    • Schwarzbauer, C., J. Syha, and A. Haase, Quantification of Regional Blood Volume by Rapid T1 Mapping. Mag. Res. Med., 1993. 29: p. 709-712.
    • Cunningham, C.H., J.M. Pauly, and K.S. Nayak, Saturated Double-Angle Method for Rapid B1+ Mapping. Mag. Res. Med., 2006. 55: p. 1326-1333.
    • Yarnykh, V.L., Actual Flip-Angle Imaging in the Pulsed Steady State: A Method for Rapid Three-Dimensional Mapping of the Transmitted Radiofrequency Field. Mag. Res. Med., 2007.
    • 57: p. 192-200.
    • Majumdar, T2 Relaxation Time Histograms in Multiple Sclerosis. Magnetic Resonance Imaging, 2002. 20: p. 733-741.
    • Cox, E.F. and P. Gowland, Simultaneous Quantification of T2 and T2' Using a Combined Gradient Echo-Spin Echo Sequence at Ultrahigh Field. Mag. Res. Med., 2010. 64: p. 1441- 1446.
    • Asllani, I., A. Borogovac, and T.R. Brown, Regression Algorithm Correcting for Partial Volume Effects in Arterial Spin Labeling MRI. Magnetic Resonance in Medicine, 2008.
    • 60(6): p. 1362-1371.
    • Zur, Y., M.L. Wood, and L.J. Neuringer, Spoiling of Transverse Magnetization in Steady-State Sequences. Magnetic Resonance in Medicine, 1991. 21: p. 251-263.
    • 2010, Cambridge: Cambridge University Press.
    • Sacolick, L.I., F. Wiesinger, I. Hancu, and M.W. Vogel, B1 mapping by Bloch-Siegert shift.
    • Magnetic Resonance in Medicine. 63(5): p. 1315-1322.
    • Lu, H., M. Law, G. Johnson, Y. Ge, P.C.M. van Zijl, and J.A. Helpern, Novel approach to the measurement of absolute cerebral blood volume using vascular-space-occupancy magnetic resonance imaging. Magnetic Resonance in Medicine, 2005. 54(6): p. 1403-1411.
    • Moran, P.R., N.G. Kumar, N. Karstaedt, and S.C. Jackels, Tissue contrast enhancement: Image reconstruction algorithm and selection of TI in inversion recovery MRI. Magnetic Resonance Imaging, 1986. 4(3): p. 229-235.
    • Winnik, M.F. Reiser, and S.O. Schoenberg, Phase-Sensitive Inversion Recovery (PSIR) SingleShot TrueFISP for Assessment of Myocardial Infarction at 3 Tesla. Investigative Radiology, 2006. 41(2): p. 148-153.
    • Hou, P., K.M. Hasan, C.W. Sitton, J.S. Wolinsky, and P.A. Narayana, Phase-Sensitive T1 Inversion Recovery Imaging: A Time-Efficient Interleaved Technique for Improved Tissue Contrast in Neuroimaging. American Journal of Neuroradiology, 2005. 26(6): p. 1432- 1438.
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