title: Automated multiscale vessel analysis for the quantification of MR angiography of peripheral arteriogenesis.
abstract: OBJECTIVE
  To automatically analyze the time course of collateralization in a rat hindlimb ischemia model based on signal intensity distribution (SID).
  
  
  METHODS
  Time-of-flight magnetic resonance angiograms (TOF-MRA) were acquired in eight rats at 2, 7, and 21 days after unilateral femoral artery ligation. Analysis was performed on maximum intensity projections filtered with multiscale vessel enhancement filter. Differences in SID between ligated limb and a reference region were monitored over time and compared to manual collateral artery identification.
  
  
  RESULTS
  The differences in SID correlated well with the number of collateral arteries found with manual quantification. The time courses of ultrasmall (diameter ≪0.5 mm) and small (diameter ≈0.5 mm) collateral artery development could be differentiated, revealing that maturation of the collaterals and enlargement of their feeding arteries occurred mainly after the first week postligation.
  
  
  CONCLUSIONS
  SID analysis performed on axial maximum intensity projections is easy to implement, fast, and objective and provides more insight in the time course of arteriogenesis than manual identification.
authors: Cardiovascular Research Institute Maastricht, Maastricht, Netherlands.
authors: Karolien
authors: K
authors: Jaspers
authors: Jos M G M
authors: JM
authors: Slenter
authors: Tim
authors: T
authors: Leiner
authors: Allard
authors: A
authors: Wagenaar
authors: Mark J
authors: MJ
authors: Post
authors: Walter H
authors: WH
authors: Backes
mesh_terms: D000818:Animals; D001157:Arterial Occlusive Diseases / Q000473:pathology*; D003097:Collateral Circulation; D005263:Femoral Artery / Q000293:injuries / Q000473:pathology*; D006614:Hindlimb / Q000098:blood supply* / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D007511:Ischemia / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D018919:Neovascularization, Physiologic; D051381:Rats; D017207:Rats, Sprague-Dawley