Cerebral collateral magnetic resonance imaging

Abstract

Objective To evaluate collateral flows using vessel encoded arterial spin labeling (VE-ASL) perfusion imaging. Methods VE-ASL was achieved to assess the presence and function of collateral flow on patients with internal carotid artery (ICA) stenosis. The presence of the anterior and posterior collateral flow was demonstrated by flow patterns of the A1 segment and posterior communicating artery (PCoA). Distal function of collateral flow of stenotic hemisphere was categorized as adequate ( cerebral blood flow ≥10 ml · min-1·100 g-1 ) or deficient (cerebral blood flow < 10 ml · min-1· 100 g-1 ). The results were compared with magnetic resonance angiography (MRA) and intraarterial digital subtraction angiography (DSA) in crosstable by using Kappa values. The VE-ASL before and after ICA stent therapy were compared. Results The Kappa values of the flow patterns of AI segment and PCoA between VE-ASL and MRA were 0. 746 and 0. 700. The Kappa value of the function of collaterals using VE-ASL and DSA was 914. VE-ASL showed collateral flow via leptomeningeal anastomoses. VE-ASL changed significantly after ICA steat therapy. Conclusion VE-ASL reveals the presence and distal function of collateral flow, which helps to evaluate the efficacy of ICA steat therapy. Key words: Carotid stenosis; Collateral circulation; Magnetic resonance imaging