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Search Publications by: Kathryn Keenan (Fed)

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Displaying 51 - 75 of 92

Characterization of 3-Dimensional Printing and Casting Materials for use in Computed Tomography and X-ray Imaging Phantoms

September 15, 2020
Author(s)
Bryan E. Yunker, Andrew Holmgren, Karl Stupic, J. L. Wagner, S Huddle, R Shandas, R. F. Weir, Katy Keenan, Edward Garboczi, Stephen E. Russek
Imaging phantoms are used to calibrate and validate the performance of medical computed tomography (CT) systems. Many new materials developed for three-dimensional (3D) printing processes may be useful in the direct printing or casting of biomimetic and

Characterization of 3-Dimensional Printing and Casting Materials for use in Magnetic Resonance Imaging Phantoms at 3 T

September 15, 2020
Author(s)
Bryan E. Yunker, Karl Stupic, J. L. Wagner, S Huddle, R Shandas, R. F. Weir, Stephen E. Russek, Katy Keenan
Imaging phantoms are used to calibrate and validate the performance of magnetic resonance imaging (MRI) systems. Many new materials have been developed for additive manufacturing (three-dimensional [3D] printing) processes that may be useful in the direct

Electromagnetics for Quantitative Magnetic Resonance Imaging

July 20, 2020
Author(s)
Stephen E. Russek, Karl F. Stupic, Joshua R. Biller, Michael A. Boss, Kathryn E. Keenan, Elizabeth Mirowski
Magnetic Resonance Imaging (MRI) is based on radio frequency (RF) interrogation of the human body at frequencies between 40 MHz to 300 MHz. An RF transmitter excites proton spin precession and then, in a manner analogous to an RF ID tag, the proton’s

T1 Mapping Performance and Measurement Stability: Results from the Multi-National T1MES (T1 Mapping and ECV Standardization) Phantom Program

May 7, 2020
Author(s)
Gabriella Captur, Abhiyan Bandari, Ye Yang, Richard James, Giulia Benedetti, Camilla Torlasco, Lewis Ricketts, Redha Boubertakh, Katy Keenan, Ruediger Bruehl, Bernd Itterman, Nasri Fatih, John Greenwood, Leonie Paulis, Chris Lawton, Chiara Bucciarelli-Ducci, Hildo Lamb, Richard Steeds, Steve Leung, Colin Berry, Sinitsyn Valentin, Andrew Flett, Charlotte de Lange, Francesco DeCobelli, Magalie Viallon, Pierre Croisille, David Higgins, Andreas Greiser, Wenjie Peng, Christian Hamilton-Craig, Wendy Strugnell, Tom Dresselaers, Andrea Barison, Dana Dawson, Andrew Taylor, Francois-Pierre Mongeon, Sven Plein, Daniel Messroghli, Mouaz Al-Mallah, Stuart Grieve, Massimo Lombardi, Jihye Jang, Michael Salerno, Nish Chaturvedi, Peter Kellman, David Bluemke, Reza Nezafat, Peter Gatehouse, James C. Moon

Progress Towards Standards for Quantitative MRI (qMRI) and Outstanding Needs

January 24, 2019
Author(s)
Kathryn E. Keenan, Joshua R. Biller, Michael A. Boss, Adele P. Peskin, Karl F. Stupic, Stephen E. Russek, Jana Delfino, Mark Does, Jeffrey L. Evelhoch, Mark Griswold, Jeffrey Gunter, R Scott Hinks, Stuart Hoffman, Geena Kim, Riccardo Lattanzi, Xiaojuan Li, Luca Marinelli, Pratik Mukherjee, Robert J. Nordstrom, Elena Perez, Berkman Sahiner, Natalie J. Serkova, Amita Shukla-Dave, Michael Steckner, Lisa J. Wilmes, Holden Wu, Huiming Zhang, Edward F. Jackson, Daniel Sullivan
The National Institute of Standards and Technology (NIST) MRI Standards project held a one-day workshop on August 4, 2017 on campus in Boulder, CO. The goal of the workshop was to evaluate the advances in quantitative MRI (qMRI) since the last NIST

Large T1 contrast enhancement using superparamagnetic nanoparticles in ultra-low field MRI

June 5, 2018
Author(s)
Xiaolu Yin, Stephen E. Russek, Gary Zabow, Fan Sun, Jeotikanta Mohapatra, Kathryn E. Keenan, Michael A. Boss, Hao Zeng, Sy-Hwang Liou, John M. Moreland
Superparamagnetic iron oxide nanoparticles (SPIONs) are widely investigated and utilized as magnetic resonance imaging (MRI) contrast and therapy agents due to their large magnetic moments. Local field inhomogeneities caused by these high magnetic moments

Magnetic Resonance Imaging Biomarker Calibration Service: Proton Spin Relaxation Times

May 3, 2018
Author(s)
Michael A. Boss, Andrew M. Dienstfrey, Zydrunas Gimbutas, Kathryn E. Keenan, Jolene D. Splett, Karl F. Stupic, Stephen E. Russek
This document describes the calibration service to measure proton spin relaxation times, T1 and T2, of materials used in phantoms (calibration artifacts) to verify the accuracy of MRI-based quantitative measurements. Proton spin relaxation times are used

Quantitative Magnetic Resonance Imaging Phantoms: A Review and the Need for a System Phantom

October 4, 2017
Author(s)
Kathryn E. Keenan, Maureen Ainslie, Alexander J. Barker, Michael A. Boss, Kim M. Cecil, Cecil Charles, Thomas L. Chenevert, Laurence Clarke, Jeffrey L. Evelhoch, Paul Finn, Guoying Liu, Stephen E. Russek, Karl F. Stupic, Joshua D. Trzasko, Chun Yuan, Jie Zheng
The MRI community is using quantitative mapping techniques to complement qualitative imaging. For quantitative imaging to reach its full potential, it is necessary to analyze measurements across systems and longitudinally. Clinical use of quantitative