Flow sensitivity analysis of variable refocusing angle 3D FSE
نویسندگان
چکیده
Introduction: FSE sequences can be adapted either to maintain brightness or to suppress the signal of moving blood. Subtraction methods with FSE can generate angiographic images without injection of contrast agents [1]. 3D FSE variants with variable refocusing angle (VRA) of the echo train are naturally suitable for high scanning efficiency and SAR reduction [2]. We analyze sequence parameter modifications to adapt 3D VRA FSE sequences for Fresh Blood Imaging (FBI) angiography.
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SNR Analysis of Variable Refocusing Flip Angle FSE
R. F. Busse Applied Science Lab West, GE Medical Systems, Menlo Park, CA, United States Introduction For fast spin echo sequences, power can be greatly reduced while suffering only modest reduction in signal by using low flip angle refocusing pulses, provided the flip angles of the first few pulses are modulated so as to maintain pseudo-steady-state (pss) conditions in the spin system (1). Rece...
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Recent advances have reduced scan time in three-dimensional fast spin echo (3D-FSE) imaging, including very long echo trains through refocusing flip angle (FA) modulation and 2D-accelerated parallel imaging. This work describes a method to modulate refocusing FAs that produces sharp point spread functions (PSFs) from very long echo trains while exercising direct control over minimum, center-k-s...
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