Image based magnetic field background correction for aortic and pulmonary artery flow measurement using phase contrast
نویسندگان
چکیده
Methods A large gel phantom was used to assess phase offset in through-plane phase contrast images in x (left to right), y (anterior to posterior) and z directions at the isocenter and in positions ±40 mm and ±80 mm away from the isocenter. Repeated measures were averaged and fit to linear regressions. Phase correction was validated in human study for the assessment of aorta and pulmonary artery (PA) flow which was followed immediately by a phantom scan using the same settings. The aorta and PA flow corrected by the regression calculated background phase was compared to that corrected by the measured background phase in the phantom study.
منابع مشابه
Image based background magnetic field correction for aortic and pulmonary artery flow measurement using phase contrast
Methods Twelve volunteers underwent breath-hold through-plane phase contrast (PC) imaging of cross sectional view of the ascending aorta and PA. PC imaging was immediately repeated on a static fluid-filled phantom. Phase images were analyzed using QFlow (Medis, Leiden, Netherlands.). Phase shift was also analyzed in static background and in surrounding tissues including chest wall fat and muscl...
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