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155261 https://hdl.handle.net/2286/R.I.43913 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2017 xiv 135 pages : illustrations (some color) Doctoral Dissertation Academic theses Text eng Turley, Dallas C Pipe, James G Kodibagkar, Vikram Frakes, David Sadleir, Rosalind Schmainda, Kathleen Arizona State University Partial requirement for: Ph.D., Arizona State University, 2017 Includes bibliographical references (pages 118-124) Field of study: Bioengineering Dynamic susceptibility contrast MRI (DSC-MRI) is a powerful tool used to quantitatively measure parameters related to blood flow and volume in the brain. The technique is known as a “bolus-tracking” method and relies upon very fast scanning to accurately measure the flow of contrast agent into and out of a region of interest. The need for high temporal resolution to measure contrast agent dynamics limits the spatial coverage of perfusion parameter maps which limits the utility of DSC-perfusion studies in pathologies involving the entire brain. Typical clinical DSC-perfusion studies are capable of acquiring 10-15 slices, generally centered on a known lesion or pathology.<br/><br/>The methods developed in this work improve the spatial coverage of whole-brain DSC-MRI by combining a highly efficient 3D spiral k-space trajectory with Generalized Autocalibrating Partial Parallel Acquisition (GRAPPA) parallel imaging without increasing temporal resolution. The proposed method is capable of acquiring 30 slices with a temporal resolution of under 1 second, covering the entire cerebrum with isotropic spatial resolution of 3 mm. Additionally, the acquisition method allows for correction of T1-enhancing leakage effects by virtue of collecting two echoes, which confound DSC perfusion measurements. The proposed DSC-perfusion method results in high quality perfusion parameter maps across a larger volume than is currently available with current clinical standards, improving diagnostic utility of perfusion MRI methods, which ultimately improves patient care. Medical Imaging Magnetic resonance imaging Diagnostic imaging Improved spatial coverage of high-temporal resolution dynamic susceptibility contrast-MRI through 3D spiral-based acquisition and parallel imaging