title: Toward Precision and Reproducibility of Diffusion Tensor Imaging: A Multicenter Diffusion Phantom and Traveling Volunteer Study.
abstract: Precision medicine is an approach to disease diagnosis, treatment, and prevention that relies on quantitative biomarkers that minimize the variability of individual patient measurements. The aim of this study was to assess the intersite variability after harmonization of a high-angular-resolution 3T diffusion tensor imaging protocol across 13 scanners at the 11 academic medical centers participating in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury multisite study.
  
  
  
  Diffusion MR imaging was acquired from a novel isotropic diffusion phantom developed at the National Institute of Standards and Technology and from the brain of a traveling volunteer on thirteen 3T MR imaging scanners representing 3 major vendors (GE Healthcare, Philips Healthcare, and Siemens). Means of the DTI parameters and their coefficients of variation across scanners were calculated for each DTI metric and white matter tract.
  
  
  
  For the National Institute of Standards and Technology diffusion phantom, the coefficients of variation of the apparent diffusion coefficient across the 13 scanners was <3.8% for a range of diffusivities from 0.4 to 1.1 × 10-6mm2/s. For the volunteer, the coefficients of variations across scanners of the 4 primary DTI metrics, each averaged over the entire white matter skeleton, were all <5%. In individual white matter tracts, large central pathways showed good reproducibility with the coefficients of variation consistently below 5%. However, smaller tracts showed more variability, with the coefficients of variation of some DTI metrics reaching 10%.
  
  
  
  The results suggest the feasibility of standardizing DTI across 3T scanners from different MR imaging vendors in a large-scale neuroimaging research study.
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.).
authors.forename: E M
authors.identifier: 0000-0001-8849-6140
authors.initials: EM
authors.lastname: Palacios
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.).
authors.forename: A J
authors.identifier: 0000-0002-7963-4000
authors.initials: AJ
authors.lastname: Martin
authors.affiliation: National Institute of Standards and Technology (M.A.B.), Boulder, Colorado.
authors.forename: M A
authors.identifier: 0000-0002-9492-767X
authors.initials: MA
authors.lastname: Boss
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.).
authors.forename: F
authors.identifier: 0000-0003-4622-3755
authors.initials: F
authors.lastname: Ezekiel
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.).
authors.forename: Y S
authors.identifier: 0000-0002-9539-4553
authors.initials: YS
authors.lastname: Chang
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.).|Brain and Spinal Cord Injury Center (E.L.Y., M.J.V., P.M.), San Francisco General Hospital and Trauma Center, San Francisco, California.
authors.forename: E L
authors.identifier: 0000-0002-1180-2274
authors.initials: EL
authors.lastname: Yuh
authors.affiliation: Neurological Surgery and Brain and Spinal Injury Center (M.J.V.).|Brain and Spinal Cord Injury Center (E.L.Y., M.J.V., P.M.), San Francisco General Hospital and Trauma Center, San Francisco, California.
authors.forename: M J
authors.identifier: 0000-0001-6748-6939
authors.initials: MJ
authors.lastname: Vassar
authors.affiliation: Department of Psychology (D.M.S.), University of Texas, Austin, Texas.
authors.forename: D M
authors.identifier: 0000-0002-7472-2853
authors.initials: DM
authors.lastname: Schnyer
authors.affiliation: Department of Neurological Surgery (C.L.M.), University of Washington, Seattle, Washington.
authors.forename: C L
authors.identifier: 0000-0002-7419-996X
authors.initials: CL
authors.lastname: MacDonald
authors.affiliation: Mark and Mary Stevens Neuroimaging and Informatics Institute (K.L.C., A.I., A.W.T.), University of Southern California, Los Angeles, California.
authors.forename: K L
authors.identifier: 0000-0002-3294-0828
authors.initials: KL
authors.lastname: Crawford
authors.affiliation: Mark and Mary Stevens Neuroimaging and Informatics Institute (K.L.C., A.I., A.W.T.), University of Southern California, Los Angeles, California.
authors.forename: A
authors.identifier: 0000-0002-9254-9388
authors.initials: A
authors.lastname: Irimia
authors.affiliation: Mark and Mary Stevens Neuroimaging and Informatics Institute (K.L.C., A.I., A.W.T.), University of Southern California, Los Angeles, California.
authors.forename: A W
authors.identifier: 0000-0003-1454-8643
authors.initials: AW
authors.lastname: Toga
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (E.M.P., A.J.M., F.E., Y.S.C., E.L.Y., P.M.) pratik.mukherjee@ucsf.edu.|Bioengineering and Therapeutic Sciences (P.M.), University of California, San Francisco, San Francisco, California.|Brain and Spinal Cord Injury Center (E.L.Y., M.J.V., P.M.), San Francisco General Hospital and Trauma Center, San Francisco, California.
authors.forename: P
authors.identifier: 0000-0001-7473-7409
authors.initials: P
authors.lastname: Mukherjee
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging*; D056324:Diffusion Tensor Imaging / Q000379:methods / Q000592:standards*; D006801:Humans; D059906:Neuroimaging / Q000379:methods / Q000592:standards*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D014838:Volunteers