title: Clinical performance of a free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced pediatric abdominal MR angiography.
abstract: BACKGROUND
  Pediatric contrast-enhanced MR angiography is often limited by respiration, other patient motion and compromised spatiotemporal resolution.
  
  
  OBJECTIVE
  To determine the reliability of a free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced MR angiography method for depicting abdominal arterial anatomy in young children.
  
  
  METHODS
  With IRB approval and informed consent, we retrospectively identified 27 consecutive children (16 males and 11 females; mean age: 3.8 years, range: 14 days to 8.4 years) referred for contrast-enhanced MR angiography at our institution, who had undergone free-breathing spatiotemporally accelerated time-resolved contrast-enhanced MR angiography studies. A radio-frequency-spoiled gradient echo sequence with Cartesian variable density k-space sampling and radial view ordering, intrinsic motion navigation and intermittent fat suppression was developed. Images were reconstructed with soft-gated parallel imaging locally low-rank method to achieve both motion correction and high spatiotemporal resolution. Quality of delineation of 13 abdominal arteries in the reconstructed images was assessed independently by two radiologists on a five-point scale. Ninety-five percent confidence intervals of the proportion of diagnostically adequate cases were calculated. Interobserver agreements were also analyzed.
  
  
  RESULTS
  Eleven out of 13 arteries achieved acceptable image quality (mean score range: 3.9-5.0) for both readers. Fair to substantial interobserver agreement was reached on nine arteries.
  
  
  CONCLUSIONS
  Free-breathing spatiotemporally accelerated 3-D time-resolved contrast-enhanced MR angiography frequently yields diagnostic image quality for most abdominal arteries in young children.
authors.affiliation: Department of Radiology, Stanford University, 350 Serra Mall, Packard 212, Stanford, CA, 94305, USA. tzhang08@stanford.edu.|Department of Electrical Engineering, Stanford University, Stanford, CA, USA. tzhang08@stanford.edu.
authors.forename: Tao
authors.identifier: http://orcid.org/0000-0001-7329-8598
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Stanford University, 350 Serra Mall, Packard 212, Stanford, CA, 94305, USA.
authors.forename: Ufra
authors.initials: U
authors.lastname: Yousaf
authors.affiliation: Department of Radiology, University of California, San Diego, San Diego, CA, USA.
authors.forename: Albert
authors.initials: A
authors.lastname: Hsiao
authors.affiliation: Department of Radiology, Stanford University, 350 Serra Mall, Packard 212, Stanford, CA, 94305, USA.|Department of Electrical Engineering, Stanford University, Stanford, CA, USA.
authors.forename: Joseph Y
authors.initials: JY
authors.lastname: Cheng
authors.affiliation: Department of Radiology, Stanford University, 350 Serra Mall, Packard 212, Stanford, CA, 94305, USA.
authors.forename: Marcus T
authors.initials: MT
authors.lastname: Alley
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, CA, USA.|Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Lustig
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, CA, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Pauly
authors.affiliation: Department of Radiology, Stanford University, 350 Serra Mall, Packard 212, Stanford, CA, 94305, USA.
authors.forename: Shreyas S
authors.initials: SS
authors.lastname: Vasanawala
mesh_terms: D000005:Abdomen / Q000033:anatomy & histology* / Q000098:blood supply*; D000293:Adolescent; D001158:Arteries / Q000033:anatomy & histology*; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007223:Infant; D007231:Infant, Newborn; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D012680:Sensitivity and Specificity; D062211:Spatio-Temporal Analysis
chemical_list: D003287:Contrast Media
keywords: Children; Compressed sensing; Magnetic resonance angiography; Parallel imaging; Spatiotemporal acceleration