Very Fast T2* Imaging by Using Improved Echo-Shifted Gradient-Recalled-Echo (iESGRE)

INTRODUCTION Echo-Shifted Gradient-Recalled-Echo (ESGRE) can be used to rapidly acquire MR images with strong T2* sensitivity [1, 2]. In this approach, excited spins are precessing over multiple TRs before each gradient echo is recalled. Therefore, the effective T2* weighting period in ESGRE is longer than one TR (TE>TR). This property makes it attractive in various clinical applications to significantly reduce scan time, such as volumetric T2* brain imaging and bolus tracking [1-4]. However, in most of reported applications, only one TR was shifted since the original ESGRE approach tends to produce strong ghosting artifacts for multipleTR shift. Here, we demonstrate an improved ESGRE (iESGRE) method, which can be used to acquire ghosting free T2* images with an arbitrary echo shift index.