Biomaterial Database

Cortical blood flow: thermal diffusion vs isotope clearance. 1981

L P Carter, and R Erspamer, and W J Bro

A thermal diffusion flow probe incorporating a Peltier stack has been found to give a quantitative dynamic assessment of cortical blood flow in both the laboratory and clinical settings. Further calibration characteristics of the probe were evaluated by correlation with the fast component of Xe133 clearance in cats. The correlation has some linear characteristics but is better defined by the equation: CBFp = phi(1/delta V - 1/delta Vo) Where CBFp is flow in ml/100 g/min, delta V is the voltage difference of the thermocouples, and delta Vo is the voltage difference of the thermocouples with no flow, which was 342.8 +/- 12.9 microv. Phi describes the characteristics of the probe and was determined to be 52,431.2 +/- 4796.3. The average deviation of the calculated curve from the experimental data points was +/- 6.3. The calculated phi differed markedly from the mean when Xe133 fast component flows were less than 35 ml/100 g/min. This is evidence that CBF as measured by Xe133 clearance analyzed by the bicompartmental technique loses accuracy at lower flows. The thermal diffusion flow probe is a good device for evaluation of flow in acute ischemia models since it can delineate abrupt flow variations. Theoretically the flow probe can accurately measure flow at ischemic levels.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D011865	Radioisotope Dilution Technique	Method for assessing flow through a system by injection of a known quantity of radionuclide into the system and monitoring its concentration over time at a specific point in the system. (From Dorland, 28th ed)	Radioisotope Dilution Technic,Dilution Technic, Radioisotope,Dilution Technics, Radioisotope,Dilution Technique, Radioisotope,Dilution Techniques, Radioisotope,Radioisotope Dilution Technics,Radioisotope Dilution Techniques,Technic, Radioisotope Dilution,Technics, Radioisotope Dilution,Technique, Radioisotope Dilution,Techniques, Radioisotope Dilution
D012039	Regional Blood Flow	The flow of BLOOD through or around an organ or region of the body.	Blood Flow, Regional,Blood Flows, Regional,Flow, Regional Blood,Flows, Regional Blood,Regional Blood Flows
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D004058	Diffusion	The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.	Diffusions
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013815	Thermodilution	Measurement of blood flow based on induction at one point of the circulation of a known change in the intravascular heat content of flowing blood and detection of the resultant change in temperature at a point downstream.	Thermodilutions
D014980	Xenon Radioisotopes	Unstable isotopes of xenon that decay or disintegrate emitting radiation. Xe atoms with atomic weights 121-123, 125, 127, 133, 135, 137-145 are radioactive xenon isotopes.	Radioisotopes, Xenon