Method and apparatus for measuring blood flow noninvasively
US4103679A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 22, 1977 |
| Grant date | Aug 1, 1978 |
| Priority date | — |
| Expiry date | Mar 22, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/582
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for noninvasive, quantitative measurement of blood flow rate in a blood vessel includes a transducer array placed on the skin surface above the vessel of interest. The array is formed of transmitting and receiving elements for transmitting and receiving beams of ultrasonic energy. Pulsed ultrasonic energy is transmitted by the array into the body tissue and intercepts the flow in the blood vessel at a slant angle which is determined by electronically steering the transmitted beam, causing it to rotate through a predetermined angular change. The resulting Doppler frequency shifts of the received ultrasonic energy backscattered by moving particles of the blood flow associated with the angular orientation of the transmitted beam can then be measured. Through electronic range gating techniques, the Doppler frequency shifts at the determined slant angle are measured at various depths or ranges below the skin at different positions across the vessel cross-section. From the aforementioned Dopper frequency shifts and slant angle, the velocity profile of the blood through a cross-section of the vessel can be determined and the blood flow rate at any instance of time c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.