Ultrasonic flow velocity imaging systems with velocity image presistence
November 21, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesAutocorrelation apparatus and method for approximating the occurrence of a generally periodic but unknown signal Ultrasonic diagnostic equipment Conversion control circuit for image display apparatus Doppler velocity processing method and apparatus Ultrasonic diagnosis apparatus for displaying speed or correlation between speed and speed dispersion by color change Ultrasonic doppler diagnostic apparatus Apparatus and method for displaying ultrasonic data Patent #: 5123417 InventorsAssigneeApplicationNo. 799667 filed on 11/21/1991US Classes:600/454, Blood flow studies600/458Contrast enhancementExaminersPrimary: Howell, Kyle L.Assistant: Manuel, George Attorney, Agent or FirmInternational ClassA61B 008/06AbstractAn ultrasonic diagnostic imaging system is described which enhances the presentation of flow velocity images through asymmetric persistence of visually displayed changes in fluid velocity. Preferably the asymmetric persistence employs a shorter (i.e., faster) time constant for increases in fluid velocity and a longer (i.e., slower) time constant for decreases in fluid velocity. In a preferred embodiment of the present invention, increases in fluid velocity are displayed at their rate of occurrence, and decreases in fluid velocity are displayed with a longer, user-selectable time constant. In the preferred embodiment the persistence enhancement is determined as a function of displayed image frame rate so that the persistence time constant remains fixed as a function of time despite user changes affecting the frame rate. | |
