title: Utilizing magnetization transfer imaging to investigate tissue remodeling in a murine model of autosomal dominant polycystic kidney disease.
abstract: OBJECTIVE
  Noninvasive imaging techniques that quantify renal tissue composition are needed to more accurately ascertain prognosis and monitor disease progression in polycystic kidney disease (PKD). Given the success of magnetization transfer (MT) imaging to characterize various tissue remodeling pathologies, it was tested on a murine model of autosomal dominant PKD.
  
  
  METHODS
  C57Bl/6 Pkd1 R3277C mice at 9, 12, and 15 months were imaged with a 16.4T MR imaging system. Images were acquired without and with RF saturation in order to calculate MT ratio (MTR) maps. Following imaging, the mice were euthanized and kidney sections were analyzed for cystic and fibrotic indices, which were compared with statistical parameters of the MTR maps.
  
  
  RESULTS
  The MTR-derived mean, median, 25th percentile, skewness, and kurtosis were all closely related to indices of renal pathology, including kidney weight/body weight, cystic index, and percent of remaining parenchyma. The correlation between MTR and histology-derived cystic and fibrotic changes was R(2) = 0.84 and R(2) = 0.70, respectively.
  
  
  CONCLUSIONS
  MT imaging provides a new, noninvasive means of measuring tissue remodeling PKD changes and may be better suited for characterizing renal impairment compared with conventional MR techniques.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Kline
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Maria V
authors.initials: MV
authors.lastname: Irazabal
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Behzad
authors.initials: B
authors.lastname: Ebrahimi
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Katharina
authors.initials: K
authors.lastname: Hopp
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Kelly N
authors.initials: KN
authors.lastname: Udoji
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Warner
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Korfiatis
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Prasanna K
authors.initials: PK
authors.lastname: Mishra
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Slobodan I
authors.initials: SI
authors.lastname: Macura
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Sudhakar K
authors.initials: SK
authors.lastname: Venkatesh
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Lilach O
authors.initials: LO
authors.lastname: Lerman
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.|Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Harris
authors.affiliation: Division of Nephrology and Hypertension Research, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Vicente E
authors.initials: VE
authors.lastname: Torres
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Bernard F
authors.initials: BF
authors.lastname: King
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Erickson
mesh_terms: D000818:Animals; D005260:Female; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007668:Kidney / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016891:Polycystic Kidney, Autosomal Dominant / Q000000981:diagnostic imaging*
keywords: Gaussian mixture model; fibrosis; histology; in vivo imaging; quantitative MRI; skewness