Meeting Banner
Abstract #1172

Pre-Emphasis Compensation of Oscillatory Phase Offsets in Phase-Contrast Flow Measurements

SUMMA25Julia Busch1, Signe Johanna Vannesjoe1, Daniel Giese1, 2, Christoph Barmet1, Klaas Pruessmann1, Sebastian Kozerke1, 2

1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; 2Division of Imaging Sciences and Biomedical Engineering, Kings College London, London, United Kingdom

Phase-contrast magnetic resonance imaging provides high resolution information about blood flow, however its application in a clinical setting is still limited due to its sensitivity to phase errors. Phase oscillations caused by mechanical vibrations of the gradient coils account for various degrees of phase offsets depending on the echo time point. A generic system-specific pre-emphasis would offer the possibility to compensate for 0th and 1st order phase offsets without the disadvantage of causing additional scan time. Focusing on the mechanical vibrations of the z-gradient it is demonstrated that pre-emphasis can reduce phase errors well below 1% of the encoding velocity.

Abstract PDF Poster PDF

Keywords

according accordingly accuracy acquisition addressed adds adjustment aims aligned amplitude aortic apparent application approximated axis background best biomedical calibration camera cardiac cause caused characteristic cine clinical coarse coefficient coefficients coil collected college compensated compensation complexity component comprehensive concerned concomitant considered constant contrast correction correspond cross degrees demanding depending derived despite determined diameter differ distributed division eddy emphasis encoded encoding engineering error every evolution experiment field fitted flow fluctuations frequency function functions future gatehouse general generic goal gradient healthy identified impulse in vivo includes individual initial insets institute investigate issues king kingdom limited linear measured mechanical modeled moments monitoring need offset offsets orientation oscillation oscillations oscillatory overall peak phantom physical previously procedure promise proportional protocol proton providing radian read realm recorded reduced reduces required resolution response separate setting sinusoidal smooth spatial spatially sphere static step subjects subsequently successfully system temporally term terms theory thereby third tissue translation triggered various velocity vibrations view visualization zoom