Medical Physics Seminar – Monday, February 9, 2015
Improved correction, reconstruction, and analysis methods for 4D-Flow MRI
Michael Loecher (student of Dr. Oliver Wieben)
Research Assistant, Medical Radiation Research Center, Dept of Medical Physics, UW-School of Medicine & Public Health, Madison, WI - USA
4D-Flow Magnetic Resonance Imaging allows for the measuring of dynamic vascular hemodynamics with full volumetric coverage and sub millimeter resolution. While successful clinical applications of this technique are plentiful, many vascular pathologies are difficult to image due to the presence of imaging artifacts and insufficient velocity to noise ratios. This seminar will detail work in correcting and improving various aspects of 4D Flow MRI imaging to better depict vascular disease, particularly neurovasculature pathologies. Topics to be covered include: increasing the dynamic range of velocity measurements via a 4D Laplacian base phased unwrapping algorithm, the use of divergence-free constraints to improve velocity to noise ratios, and a method for improved streamlines and the generation of ‘virtual injections.’ Demonstrations and results are shown in digital phantoms and clinical examples.