title: Rapid volumetric T1 mapping of the abdomen using three-dimensional through-time spiral GRAPPA.
abstract: OBJECTIVE
  To develop an ultrafast T1 mapping method for high-resolution, volumetric T1 measurements in the abdomen.
  
  
  METHODS
  The Look-Locker method was combined with a stack-of-spirals acquisition accelerated using three-dimensional (3D) through-time spiral GRAPPA reconstruction for fast data acquisition. A segmented k-space acquisition scheme was proposed and the time delay between segments for the recovery of longitudinal magnetization was optimized using Bloch equation simulations. The accuracy of this method was validated in a phantom experiment and in vivo T1 measurements were performed with 35 asymptomatic subjects on both 1.5 Tesla (T) and 3T MRI systems.
  
  
  RESULTS
  Phantom experiments yielded close agreement between the proposed method and gold standard measurements for a large range of T1 values (200 to 1600 ms). The in vivo results further demonstrate that high-resolution T1 maps (2 × 2 × 4 mm(3)) for 32 slices can be achieved in a single clinically feasible breath-hold of approximately 20 s. The T1 values for multiple organs and tissues in the abdomen are in agreement with the published literature.
  
  
  CONCLUSIONS
  A high-resolution 3D abdominal T1 mapping technique was developed, which allows fast and accurate T1 mapping of multiple abdominal organs and tissues in a single breath-hold.
authors.affiliation: Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Pediatric Neuroimaging Research Consortium, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Lee
authors.affiliation: Haraldsplass Deaconess Hospital, Bergen, Norway.
authors.forename: Gunhild
authors.initials: G
authors.lastname: Aandal
authors.affiliation: Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Chaitra
authors.initials: C
authors.lastname: Badve
authors.affiliation: Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Wright
authors.affiliation: Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.|Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Griswold
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Seiberlich
authors.affiliation: Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.|Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
authors.forename: Vikas
authors.initials: V
authors.lastname: Gulani
mesh_terms: D000005:Abdomen / Q000000981:diagnostic imaging*; D000328:Adult; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D055815:Young Adult
keywords: Look-Locker method; T1 mapping; non-Cartesian sampling; parallel imaging; spiral trajectory