title: Development of a high resolution MRI intracranial atherosclerosis imaging phantom.
abstract: OBJECTIVE
  Currently, there is neither a standard protocol for vessel wall MR imaging of intracranial atherosclerotic disease (ICAD) nor a gold standard phantom to compare MR sequences. In this study, a plaque phantom is developed and characterized that provides a platform for establishing a uniform imaging approach for ICAD.
  
  
  METHODS
  A patient specific injection mold was 3D printed to construct a geometrically accurate ICAD phantom. Polyvinyl alcohol hydrogel was infused into the core shell mold to form the stenotic artery. The ICAD phantom incorporated materials mimicking a stenotic vessel and plaque components, including fibrous cap and lipid core. Two phantoms were scanned using high resolution cone beam CT and compared with four different 3 T MRI systems across eight different sites over a period of 18 months. Inter-phantom variability was assessed by lumen dimensions and contrast to noise ratio (CNR).
  
  
  RESULTS
  Quantitative evaluation of the minimum lumen radius in the stenosis showed that the radius was on average 0.80 mm (95% CI 0.77 to 0.82 mm) in model 1 and 0.77 mm (95% CI 0.74 to 0.81 mm) in model 2. The highest CNRs were observed for comparisons between lipid and vessel wall. To evaluate manufacturing reproducibility, the CNR variability between the two models had an average absolute difference of 4.31 (95% CI 3.82 to 5.78). Variation in CNR between the images from the same scanner separated by 7 months was 2.5-6.2, showing reproducible phantom durability.
  
  
  CONCLUSIONS
  A plaque phantom composed of a stenotic vessel wall and plaque components was successfully constructed for multicenter high resolution MRI standardization.
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Ju-Yu
authors.initials: JY
authors.lastname: Chueh
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Kajo
authors.identifier: http://orcid.org/0000-0003-1099-9498
authors.initials: K
authors.lastname: van der Marel
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gounis
authors.affiliation: Departments of Neurology and Radiology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Todd
authors.initials: T
authors.lastname: LeMatty
authors.affiliation: Departments of Neurology and Radiology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Truman R
authors.initials: TR
authors.lastname: Brown
authors.affiliation: Departments of Radiology, Neurology, and Neurological Surgery, Northwestern University, Chicago, Illinois, USA.
authors.forename: Sameer A
authors.initials: SA
authors.lastname: Ansari
authors.affiliation: Department of Radiology, University of Chicago, Chicago, Illinois, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Carroll
authors.affiliation: Departments of Radiology and Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA.
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Buck
authors.affiliation: Departments of Radiology, Neurosurgery, and Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Xiaohong Joe
authors.initials: XJ
authors.lastname: Zhou
authors.affiliation: Departments of Neurology and Radiology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: A Rano
authors.initials: AR
authors.lastname: Chatterjee
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: King
authors.affiliation: Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Mao
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Shaokuan
authors.initials: S
authors.lastname: Zheng
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Olivia W
authors.initials: OW
authors.lastname: Brooks
authors.affiliation: Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Jeff W
authors.initials: JW
authors.lastname: Rappleye
authors.affiliation: Department of Medicine (Neurology), Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Richard H
authors.initials: RH
authors.lastname: Swartz
authors.affiliation: Neurosciences and Rehabilitation, Baystate Health, Springfield, Massachusetts, USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Feldmann
authors.affiliation: Departments of Neurology and Radiology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Tanya N
authors.initials: TN
authors.lastname: Turan
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000295:instrumentation / Q000379:methods; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation* / Q000379:methods; D002537:Intracranial Arteriosclerosis / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D014715:Vertebrobasilar Insufficiency / Q000000981:diagnostic imaging*
keywords: Atherosclerosis; MRI; Stenosis; Vessel Wall