title: Dynamic changes in murine vessel geometry assessed by high-resolution magnetic resonance angiography: a 9.4T study.
abstract: OBJECTIVE
  To establish high-resolution magnetic resonance angiography (MRA) protocols to monitor and quantify dynamic changes of vascular remodeling in pathologic mouse models.
  
  
  METHODS
  Time-of-flight (TOF) MRA of murine vessels was performed at 9.4T to monitor temporal alterations in the vessel structure in two frequently used injury models (wire denudation of carotid artery and femoral artery occlusion). Quantification of vessel morphology was performed with the use of in-house-developed software and validated by estimation of inter- and intraobserver variabilities and reproducibility, and by correlation with histological data.
  
  
  RESULTS
  MRA-based volume determination exhibited low intra- and interobserver variabilities and high reproducibility. Furthermore, good correlations with histological data were found four weeks after injury (R2=0.970). Two high-resolution image series are presented to demonstrate the applicability of the technique: 1) the time course of a vessel stenosis that reopens by thrombus recanalization, and 2) the continuous restoration of blood flow by collateral vessel formation during arteriogenesis after induction of hindlimb ischemia.
  
  
  CONCLUSIONS
  We describe high-resolution MRA imaging protocols that are suitable for sensitively measuring the extent and time course of changes in vessel morphology in mice in a repetitive manner without any contrast agent. This methodology provides a reliable tool for noninvasive monitoring of vascular lesion development or neovascularization in transgenic mice.
authors.affiliation: Department of Cardiovascular Physiology, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany. christoph.jacoby@uni-duesseldorf.de
authors.forename: Christoph
authors.initials: C
authors.lastname: Jacoby
authors.forename: Yang Chul
authors.initials: YC
authors.lastname: Böring
authors.forename: Andreas
authors.initials: A
authors.lastname: Beck
authors.forename: Alma
authors.initials: A
authors.lastname: Zernecke
authors.forename: Volker
authors.initials: V
authors.lastname: Aurich
authors.forename: Christian
authors.initials: C
authors.lastname: Weber
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schrader
authors.forename: Ulrich
authors.initials: U
authors.lastname: Flögel
mesh_terms: D000465:Algorithms; D000818:Animals; D023921:Coronary Stenosis / Q000473:pathology*; D006614:Hindlimb / Q000098:blood supply* / Q000473:pathology; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D007511:Ischemia / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009389:Neovascularization, Pathologic / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity