Improved precision in SASHA T1 mapping with a variable flip angle readout
نویسندگان
چکیده
Background The SAturation-recovery single-SHot Acquisition (SASHA) T1 mapping sequence has excellent accuracy independent of T1, T2, heart rate, and flip angle [1], which are known dependencies of the more commonly used MOdified Look-Locker Inversion-recovery (MOLLI) sequence. However, SASHA has a greater T1 variability (poorer precision) compared to MOLLI. A two-parameter fit, with assumed ideal saturation, has been shown to improve precision compared to the standard three-parameter fit used for SASHA, but at the expense of introducing systematic errors [2]. We propose that a variable flip angle (VFA) readout will reduce these systematic errors and thereby allow the improved precision of a two-parameter fit while maintaining the accuracy of the three-parameter fit.
منابع مشابه
Variability of T1 in purpose recruited normal volunteers and patients as a function of shim (B0), flip angle (B1) and myocardial sector at 3T
Methods 36 subjects (including 20 normal volunteers) were scanned using an investigational prototype sequence on a 3T scanner (MAGNETOM Skyra, Siemens AG, Germany). T1 was measured using three Methods MOLLI with a flip angle of 20 ̊, MOLLI with flip angle 35 ̊, and 2-parameter SASHA with a variable flip angle (VFA) readout. B0 and B1 field maps were generated. Sector level, intra-subject, between...
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