A heterogeneous tissue model for measurement of regional blood perfusion in the myocardium using inert gas isotopes
Autor: | R.W. Parkey, F. J. Bonte, Ernest M. Stokely, L. R. Nardizzi |
---|---|
Rok vydání: | 1974 |
Předmět: |
Statistics and Probability
General Immunology and Microbiology Isotope business.industry Chemistry Washout curve Applied Mathematics Washout General Medicine General Biochemistry Genetics and Molecular Biology Heterogeneous tissue medicine.anatomical_structure Modeling and Simulation medicine Diffusion (business) General Agricultural and Biological Sciences Nuclear medicine business Inert gas Perfusion Biomedical engineering Artery |
Zdroj: | Mathematical Biosciences. 20:359-380 |
ISSN: | 0025-5564 |
Popis: | Inert gas isotopes are finding increasing application in the measurement of blood perfusion in the capillary beds of muscle, especially the myocardium. When measuring blood perfusion of the myocardium, washout curves are first produced by precordial monitoring of isotope activity following intracoronary artery injection of an inert gas isotope dissolved in saline. The washout curve data are then applied to a mathematical model to yield blood perfusion rate. Present models for this purpose either ignore any diffusive effects of gas movement (Kety-Schmidt model), or diffusive effects are accounted for by weighting the calculated perfusion value (Zierler's height-over-area technique). A new model is described here for convective and diffusive movement of an inert, nonpolar gas in myocardial tissue. A digital computer simulation of the model equations is used both to simply the model and to show agreement between the model response and experimental 133 Xe washout curves from normal and infracted canine hearts. The model assumes that the tail of the washout curves (portion after roughly 1.5 minutes) is caused by a heterogeneous, diffusion-limited tissue structure. The model provides two parameters which can be adjusted to washout curve data using model-matching techniques. These are perfusion rate, and a parameter which is an index of the diffusive nature of the particular myocardial area under study. |
Databáze: | OpenAIRE |
Externí odkaz: |