Patent ID: 6601459
Filing Date: 2003-08-05
Classification: A61B,G01F,G01S

Abstract:
Method to measure in vitro or in vivo the volumetric flow in blood vessels using a pulsed Doppler instrument which allows assessement of crossectional area and mean velocity for determining a real volumetric flow in the vessel, characterized in that Q=k&it;M1,3M0,3Ã—A2N+1A1N&it;M0,1N&it;M0,3M0,2N+1&it;(1-rR2)4&it;N&it;(1+NrR2)4(19)whereby Q=real volumetric flowk=c/(2fs) (c=speed of sound in medium, fs=emitted frequency) A=cross sectional area R1,2,3=radial distances of sample volumes from a transducer tip M0,1=zeroth Doppler moment of a first sample M0,2=zeroth Doppler moment of a second sample M0,3=zeroth Doppler moment of a third sample M1=first Doppler moment N=ratio of the differences in the distance between samples 2 and 3 R=R2âˆ’R1 Nr=R3âˆ’R2.