title: Quiet and distortion-free, whole brain BOLD fMRI using T2 -prepared RUFIS.
abstract: OBJECTIVE
  To develop and evaluate a novel MR method that addresses some of the most eminent technical challenges of current BOLD-based fMRI in terms of 1) acoustic noise and 2) geometric distortions and signal dropouts.
  
  
  METHODS
  A BOLD-sensitive fMRI pulse sequence was designed that first generates T2-weighted magnetization (using a T2 preparation module) and subsequently undergoes three-dimensional (3D) radial encoding using a rotating ultrafast imaging sequence (RUFIS). The method was tested on healthy volunteers at 3T with motor, visual, and auditory tasks, and compared relative to standard gradient and spin echo planar imaging (EPI) methods.
  
  
  RESULTS
  In combination with parallel imaging the method achieves efficient and robust 3D whole brain coverage (3 mm isotropic resolution in 2.65 s scan time). Compared with standard EPI-based fMRI, the method demonstrated 1) T2-weighted imaging clean of geometrical distortions and signal dropout, 2) an acoustic noise reduction of ∼40 dB(A), and 3) a consistent BOLD response that is less sensitive (∼1.3% BOLD change) but spatially more specific.
  
  
  CONCLUSIONS
  T2-prepared RUFIS provides quiet and distortion-free whole brain BOLD fMRI with minimal demands on the gradient performance. In particular, auditory fMRI and/or studies involving brain regions near air-tissue interfaces are expected to greatly benefit from the proposed method, especially if performed at ultrahigh field strengths.
authors.affiliation: GE Global Research, Munich, Germany.
authors.forename: Ana Beatriz
authors.initials: AB
authors.lastname: Solana
authors.affiliation: GE Global Research, Munich, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Menini
authors.affiliation: GE Global Research, Munich, Germany.
authors.forename: Laura I
authors.initials: LI
authors.lastname: Sacolick
authors.affiliation: GE Global Research, Munich, Germany.|Department of Medical Engineering, Technische Universität München, Munich, Germany.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Hehn
authors.affiliation: GE Global Research, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Wiesinger
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*
keywords: 3D radial; RUFIS; fMRI; geometric distortions; silent; zero TE