title: Fast high-resolution T1 mapping using inversion-recovery Look-Locker echo-planar imaging at steady state: optimization for accuracy and reliability.
abstract: A fast T(1) measurement sequence using inversion recovery Look-Locker echo-planar imaging at steady state (IR LL-EPI SS) is presented. Delay time for a full magnetization recovery is not required in the sequence, saving acquisition time significantly for high-resolution T(1) mapping. Imaging parameters of the IR LL-EPI SS sequence were optimized to minimize the bias from the excitation pulses imperfection and to maximize the accuracy and reliability of T(1) measurements, which are critical for its applications. Compared with the conventional inversion recovery Look-Locker echo-planar imaging (IR LL-EPI) sequence, IR LL-EPI SS method preserves similar accuracy and reliability, while saving 20% in acquisition time. Optimized IR LL-EPI SS provided quantitative T(1) mapping with 1 x 1 x 4 mm(3) resolution and whole-brain coverage (28 slices) in approximately 4 min.
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, USA. shinwa@mail.nih.gov
authors.forename: Wanyong
authors.initials: W
authors.lastname: Shin
authors.forename: Hong
authors.initials: H
authors.lastname: Gu
authors.forename: Yihong
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology*; D017352:Echo-Planar Imaging / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity