EP0182200A2
Expired / Lapsed
EP
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Determination of blood flow by using tracer gases and computed tomography
Assignee: General Electric Co
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Filing: 1985-11-05
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Granted: —
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Expires: 2005-11-05
Abstract
Abstract A simplified method of determining tissue blood flow such as cerebral blood flow is provided by calculating the partial derivatives with respect to flow rate constant (k) and partition coefficient (λ) of the sum of errors squared for calculated tissue concentration of a diffusible inert gas such as xenon minus measured tissue concentration of xenon based on CT numbers.
Inventors
- 👤 James George Colsher
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:49
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/026; A61B5/0275
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
80 words
A method of determining blood flow in tissue comprising the steps of applying a freely diffusible inert gas to said tissue, obtaining a measure of gas concentration in arterial blood as a function of time, obtaining measures of gas concentration in said tissue as a function of time, and obtaining the blood flow from the partial derivatives of the sum of errors squared of the measured tissue concentration less the predicted concentration with respect to partition coefficient and rate constant.
Claim 2
Independent Claim
80 words
A method of determining blood flow in tissue comprising the steps of applying a freely diffusible inert gas to said tissue, obtaining a measure of gas concentration in arterial blood as a function of time, obtaining measures of gas concentration in said tissue as a function of time, and obtaining the blood flow from the partial derivatives of the sum of errors squared of the measured tissue concentration less the predicted concentration with respect to partition coefficient and rate constant.
Claim 3
Dependent Claim
47 words
The method as defined by Claim 1 where tissue concentration of the freely diffusible inert gas is given by where, λ is the partition coefficient k is the rate constant f = Xk is flow/volume Ca(t) is the arterial concentration of gas as a function of time.
Claim 4
Dependent Claim
23 words
The method as defined by Claim 2 wherein the sum of the square of errors is given by and the partial derivatives are
Claim 5
Dependent Claim
21 words
The method as defined by Claim 1 wherein said blood flow is cerebral and said freely diffusible inert gas is xenon.
References Cited (Backward Citations)
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