Curtis L. Johnson1, 2, Matthew D.J. McGarry3, Armen A. Gharibans1, John B. Weaver4, Keith D. Paulsen3, 4, Bradley P. Sutton, 25, John G. Georgiadis1, 2
1Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States; 2Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States; 3Thayer School of Engineering, Dartmouth College, Hanover, NH, United States; 4Radiology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, United States; 5Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
Recently, MR Elastography (MRE) sequences using multi-shot readouts have been used for higher resolution acquisitions. However, multi-shot MRE is prone to significant phase errors between shots due to inconsistencies in applied motion, resulting in phase cancellation and signal loss. In this work, a multi-shot, variable-density spiral sequence is used, which allows for phase offsets to be estimated for each shot and registered across shots. Results are presented which demonstrate the improvement in image quality, octahedral shear strain-based SNR, and estimated shear modulus estimates. We present 2mm isotropic high-resolution brain MRE data with mechanical estimates obtained with the iterative NLI algorithm.