Quantitative middle cerebral artery flow in normal and vasospastic arteries.
To determine the degree of MCA vasospasm necessary to exceed the ischaemic threshold of blood flow reduction to less than 1/3 normal flow, we developed a computer model of blood flow in the middle cerebral artery distribution. When solved for a 3 mm trunk diameter, it showed a normal flow of 179 ml/min. It was necessary to decrease trunk diameter by 75%, or branch diameter by 50%, or increase peripheral resistance by a factor of 3, in order to decrease blood flow to less than 1/3 normal.
Austin
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Aneurysm Research Institute, Santa Barbara, California 93105.
Gaskell
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D002536:Cerebral Arteries / Q000502:physiology* / Q000503:physiopathology*; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology / Q000503:physiopathology; D002546:Ischemic Attack, Transient / Q000503:physiopathology*; D008433:Mathematics; D008955:Models, Cardiovascular; D012039:Regional Blood Flow; D014655:Vascular Resistance