Snapshot gradient-recalled echo-planar images of rat brains at long echo time at 9.4 T

With improved B-0 homogeneity along with satisfactory gradient performance at high magnetic fields, snapshot gradient-recalled echo-planar imaging (GRE-EPI) would perform at long echo times (TEs) oil the order of T-2*, which intrinsically allows obtaining strongly T-2*-weighted images with embedded substantial anatomical details in ultrashort time. The aim of this study was to investigate the feasibility and quality of long TE snapshot GRE-EPI images of rat brain at 9.4 T. When compensating for B-0 inhomogeneities, especially second-order shim terms, a 200x200 mu m(2) in-plane resolution image was reproducibly obtained at long TE (> 25 ms). The resulting coronal images at 30 ms had diminished geometric distortions and, thus, embedded Substantial anatomical details. Concurrently with the very consistent stability, such GRE-EPI images should permit to resolve functional data not only with high specificity but also with substantial anatomical details, therefore allowing coregistration of the acquired functional data oil the same image data set. (C) 2008 Elsevier Inc. All rights reserved.