Real-time two-dimensional resistance and pulsatility mapping
US6023968A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1995 |
| Grant date | Feb 15, 2000 |
| Priority date | — |
| Expiry date | Nov 22, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/8979
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining resistance and pulsatility indices of a flow of material, such as the flow of blood in the human body. This may be implemented, for example, in a color flow module in an ultrasonic imaging system for display of the pulsatility or resistance index in two dimensions and in different colors to allow discrimination between veins and arteries and detection of pathologic elevation of vascular resistance in a clinical survey mode of the system. The resistance index is determined from the ratio of a unipolar variation estimate of a velocity of the flow material divided by a peak velocity. The variation estimate may be one of the following: a difference between a peak velocity of the flow of material and a second minimum (if unipolar) or negative (if bipolar) velocity of the flow of material, a standard deviation .rho. of the velocity of the flow of material, a square root of a value at a first peak of an autocorrelator of the velocity of the flow of material, and a square root of a value at a second peak of the autocorrelator of the velocity of the flow of material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.