Collateral circulation imaging: MR perfusion territory arterial spin-labeling at 3T

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Collateral circulation knowledge is limited.
• Noninvasive methods for characterizing collateral roles are needed.

Purpose of the Study:

• Investigate collateral presence and distal flow using vessel-encoded arterial spin-labeling (VE-ASL).
• Assess the utility of a new MR perfusion territory imaging technique.

Main Methods:

• Fifty-six patients with ICA or MCA stenosis underwent VE-ASL.
• Perfusion data combined with VE maps to create 3-colored territory maps.
• Collateral flow presence and function (adequate/deficient CBF) assessed and compared with MRA and DSA.

Main Results:

• VE-ASL showed good agreement with MRA for collateral presence (kappa=0.785 anterior, 0.700 posterior).
• VE-ASL demonstrated strong agreement with DSA for collateral function (kappa=0.726).
• Identified collateral flow via leptomeningeal anastomoses in addition to the Circle of Willis.

Conclusions:

• VE-ASL noninvasively visualizes collateral presence, origin, and distal function in ICA/MCA stenosis.
• This technique offers a valuable tool for evaluating collateral status in cerebrovascular disease.