title: High-resolution T1-weighted gradient echo imaging for liver MRI using parallel imaging at high-acceleration factors.
abstract: OBJECTIVE
  To determine whether application of a high-acceleration parallel acquisition can provide three-dimensional (3D)-fat-suppressed T1-weighted gradient-recalled-echo (T1W-GRE) imaging at 3T for liver MR imaging.
  
  
  METHODS
  This retrospective study was approved by our institutional review board. Seventy patients underwent liver MRI at a 3T scanner. After administration of a standard dose of Gadoxetic acid for 20 min, 3D-T1W-GRE images were obtained twice using sensitivity encoding with acceleration factors (AFs) 2.6 [332 × 298 matrix, 3-mm slice thickness (ST)] and 4 (380 × 320 matrix, 1.5-mm ST). The image qualities of the two image sets were graded using a five-point scale.
  
  
  RESULTS
  The high-resolution (HR) 3D-T1W-GRE image sets were obtained with an AF 4 within a single breath-hold (18.5 s). It showed a better anatomic depiction than conventional 3D-T1W-GRE image sets with an AF 2.6 (p < 0.05). Although the image noise was higher on the HR image sets (p < 0.05), the HR image sets showed better lesion conspicuity and overall image quality than the conventional image sets (p < 0.05).
  
  
  CONCLUSIONS
  With the use of high AFs, HR 3D-T1W-GRE imaging was demonstrated to be clinically more feasible and advantageous than the conventional 3D-T1W-GRE.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea.
authors.forename: Jeong Hee
authors.initials: JH
authors.lastname: Yoon
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Mi Hye
authors.initials: MH
authors.lastname: Yu
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Kim
authors.forename: Joon Koo
authors.initials: JK
authors.lastname: Han
authors.forename: Byung Ihn
authors.initials: BI
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D017352:Echo-Planar Imaging; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA