Dynamic changes in murine vessel geometry assessed by high-resolution magnetic resonance angiography: a 9.4T study.
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.
Jacoby
Christoph
C
Department of Cardiovascular Physiology, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany. christoph.jacoby@uni-duesseldorf.de
Böring
Yang Chul
YC
Beck
Andreas
A
Zernecke
Alma
A
Aurich
Volker
V
Weber
Christian
C
Schrader
Jürgen
J
Flögel
Ulrich
U
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