Clinical Neuroscience

[THE LANDMARKS OF THE MEASUREMENT OF CEREBRAL BLOOD FLOW]

NYÁRY István

JANUARY 22, 2008

Clinical Neuroscience - 2008;61(01-02)

[History of the measurement of local cerebral blood flow may cover a period of one and a half centuries. Parallel forthcoming of both theoretical and technical development were the key elements of ensuing progress resulting in the present state, when by the aid of in vivo blood flow and metabolic maps, we can visualize locales of brain functioning and their interconnections. Two theoretical landmarks should be mentioned in this historic process. First, the work of Adolf Fick, as the starter of quantitative measurements in this field, and Seymour Kety’s model of a single, homogenously perfused tissue element. The solution of this model, in the form of Kety’s equation is still fundamental to present day blood flow mapping techniques. Among the numerous investigators over the past years, two Hungarian scientist can be named as major contributors. Kálmán Sántha made substantial studies with continuous registration of local cerebral blood flow by the aid of thermocouples, while Emil Pásztor invented the hydrogen clearance method for the measurement of local cerebral blod flow both in human and in animal studies.]

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