title: In vitro comparison of intracranial stent visibility using various concentrations of gadolinium contrast agent under 1.5 T and 3 T MR angiography.
abstract: OBJECTIVE
  MR angiography (MRA) is an increasingly used evaluation method following intracranial stenting. However, the various artifacts created by the stent limit this technique. The purpose of this study was to investigate the effects of various concentrations of gadolinium contrast agent on the visibility and signal characteristics of two stents using the a contrast enhanced MRA technique.
  
  
  METHODS
  Two intracranial stents (Enterprise and Helistent) were placed in polyvinyl chloride tubes as vascular phantoms. They were filled with six different doses of gadolinium contrast agent (1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 mmol/L dimeglumine gadopentetate, respectively) and imaged using 3 T and 1.5 T MR systems. Relative in-stent signal (RIS) was calculated and artificial luminal narrowing (ALN) was obtained using pixel by pixel analysis.
  
  
  RESULTS
  The Enterprise stent, performed in both 1.5 T and 3 T MR systems, showed mean RIS values much less than those for the Helistent for all different doses of gadolinium solution. Increased gadolinium concentration resulted in a gradual reduction in RIS values in the Enterprise group. Also, ALN in the Enterprise group showed no or little change with various gadolinium doses.
  
  
  CONCLUSIONS
  The Enterprise stent demonstrated good luminal visibility regardless of gadolinium concentration. The relative in-stent signals were more predictable in the Enterprise stent with various doses of gadolinium. Therefore, the Enterprise stent has been shown to provide better in-stent visibility compared with the Helistent using various gadolinium doses.
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.|Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors: Chen-Hua
authors: CH
authors: Chiang
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.|Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors: Ying-Chi
authors: YC
authors: Tseng
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
authors: Ai-Chi
authors: http://orcid.org/0000-0002-8134-1012
authors: AC
authors: Chen
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.|Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors: Yen-Lin
authors: YL
authors: Huang
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.|Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors: David Yen-Ting
authors: DY
authors: Chen
authors: Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.|Chia-Yi Hospital, Ministry of Health and Welfare, Chiayi City, Taiwan.
authors: Chi-Jen
authors: CJ
authors: Chen
authors: Biostatistics Center, Taipei Medical University, Taipei, Taiwan.
authors: Yen-Kuang
authors: YK
authors: Lin
authors: Department of Radiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.|Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors: Hui-Ling
authors: HL
authors: Hsu
mesh_terms: D016477:Artifacts; D003287:Contrast Media; D004305:Dose-Response Relationship, Drug; D005682:Gadolinium; D019786:Gadolinium DTPA; D006801:Humans; D066298:In Vitro Techniques; D018810:Magnetic Resonance Angiography / Q000379:methods*; D019047:Phantoms, Imaging; D015607:Stents
chemical_list: D003287:Contrast Media; D005682:Gadolinium; D019786:Gadolinium DTPA
keywords: Magnetic Resonance Angiography; Stent