Cerebral Blood Flow Quantification Using Vessel-Encoded Arterial Spin Labeling. Issue 11 (November 2013)

• Record Type: Journal Article
• Authors: Okell, Thomas W; Chappell, Michael A; Kelly, Michael E; Jezzard, Peter
• Is Part Of: Journal of cerebral blood flow & metabolism. Volume 33:Issue 11(2013)
• Page Start: 1716
• Page End: 1724
• Publication Date: 2013-11
• Subjects: ASL -- brain imaging -- cerebral blood flow measurement -- cerebral hemodynamics -- MRI; Cerebral circulation -- Periodicals; Brain -- Metabolism -- Periodicals; Brain -- Blood-vessels -- Periodicals; Cerebrovascular disease -- Periodicals; 612.824
• DOI: 10.1038/jcbfm.2013.129
• Languages: English
• ISSNs: 0271-678X

Abstract

Arterial spin labeling (ASL) techniques are gaining popularity for visualizing and quantifying cerebral blood flow (CBF) in a range of patient groups. However, most ASL methods lack vessel-selective information, which is important for the assessment of collateral flow and the arterial supply to lesions. In this study, we explored the use of vessel-encoded pseudocontinuous ASL (VEPCASL) with multiple postlabeling delays to obtain individual quantitative CBF and bolus arrival time maps for each of the four main brain-feeding arteries and compared the results against those obtained with conventional pseudocontinuous ASL (PCASL) using matched scan time. Simulations showed that PCASL systematically underestimated CBF by up to 37% in voxels supplied by two arteries, whereas VEPCASL maintained CBF accuracy since each vascular component is treated separately. Experimental results in healthy volunteers showed that there is no systematic bias in the CBF estimates produced by VEPCASL and that the signal-to-noise ratio of the two techniques is comparable. Although more complex acquisition and image processing is required and the potential for motion sensitivity is increased, VEPCASL provides comparable data to PCASL but with the added benefit of vessel-selective information. This could lead to more accurate CBF estimates in patients with a significant collateral flow.