title: Assessment of collateral flow in patients with cerebrovascular disorders.
abstract: The ability to maintain cerebral parenchymal perfusion during states of acute or chronic ischemic insult depends largely on the capacity of the cerebral collateral circulation. Perfusion techniques, including perfusion-CT and arterial spin labeling, may not only describe the overall status of the collateral network, but can also quantify the pathophysiologic collateral reserve, which is occult to conventional imaging techniques. The following review details advanced imaging modalities capable of resolving pathophysiologic collateral circulation in a functional and dynamic manner, with regards to the evaluation of both acute ischemic penumbra and chronic cerebral vascular reserve. Specifically, the applications of perfusion-CT, arterial spin labeling MRI techniques, and transcranial Doppler are reviewed in the context of collateral circulation with emphasis on perfusion techniques and proposed clinical utility.
authors.affiliation: Division of Neuroradiology, University of Virginia, Charlottesville, VA, United States.
authors.forename: Joseph
authors.initials: J
authors.lastname: Donahue
authors.affiliation: Division of Neuroradiology, University of Virginia, Charlottesville, VA, United States.
authors.forename: Suna
authors.initials: S
authors.lastname: Sumer
authors.affiliation: Division of Neuroradiology, University of Virginia, Charlottesville, VA, United States. Electronic address: max.wintermark@gmail.com.
authors.forename: Max
authors.initials: M
authors.lastname: Wintermark
mesh_terms: D001783:Blood Flow Velocity; D002533:Cerebral Angiography / Q000379:methods*; D002561:Cerebrovascular Disorders / Q000175:diagnosis / Q000503:physiopathology*; D002941:Circle of Willis / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D003097:Collateral Circulation; D006801:Humans; D007089:Image Enhancement / Q000379:methods*
keywords: Cerebrovascular accident; Cerebrovascular circulation; Collateral circulation; Perfusion Imaging