Koninklijke Philips Corporation N.v.

Georgia Tech Research Corporation

Qifeng Wei

Karl E Thiele

Ajit P Yoganathan

Choon-Hwai Yap

Mona Shrestha

An ultrasonic diagnostic imaging system is described which quantifies regurgitant flow through a mitral valve. A flow quantification processor () in the ultrasound system produces a mathematical model of a flow velocity field proximal to a regurgitant orifice. The velocity field model produces values of velocity vectors directed toward the regurgitant orifice. These modeled values are modified for the effects of ultrasound physics and ultrasound system operation to produce expected velocity values. The expected velocity values are compared with actual Doppler velocities measured by the ultrasound system, and the differences accumulated to a mean square error which is used to adjust parameters of the model such as the orifice location and flow velocities. When this iterative processing converges with a desired comparison, parameters derived from the finally adjusted model are used to calculate the true orifice location, flow rate, and volume flow.

Analysis of mitral regurgitation by ultrasonic imaging

An ultrasonic diagnostic imaging system is described which assesses regurgitant flow through a mitral valve by color-flow imaging. A Doppler processor produces Doppler velocity measurements of blood flow around a regurgitant valve to identify an iso-velocity surface to be used in the PISA method of regurgitant flow quantification. The velocity measurements are used to color pixels in the colorflow image and are mapped to a plurality of colors for a color bar used with the image. The color bar exhibits distinct color transitions at one or more velocities in the velocity range of the color bar which distinctively identify an iso-velocity surface in the colorflow image. The color bar may be formed with an aliasing velocity in the middle of the bar, between a zero velocity reference color of the bar and an end of the bar, and the aliasing velocity aligned with a desired iso-velocity and used to create the color transition.

Ultrasonic color flow map for analysis of mitral regurgitation

An ultrasonic diagnostic imaging system is described which quantifies regurgitant flow through a plurality of pinhole leaks or a slit leak of a mitral valve. A plurality of orifice locations of a leaking valve are identified and Doppler values obtained from a flow velocity field proximal each orifice. The Doppler values of each flow velocity field vectorially relating to the orifice location are processed to produce a measure of flow through the orifice. The flow measurements for a plurality of such orifices are summed to produce a quantified measure of regurgitant flow through a plurality of pinhole leaks or along a slit leak.

Analysis of mitral regurgitation from slit orifices by ultrasonic imaging

An ultrasonic diagnostic imaging system is described which quantifies regurgitant flow through a mitral valve. Echo signals received by an ultrasound probe () are used to produce an image of a regurgitant flow region, and are processed by a wall filter having a response characteristic which peaks at an intermediate sampling rate between zero and the Nyquist limits. This response characteristic is thus highly sensitive to lower flow rates which may be anticipated in a flow velocity field proximal a regurgitant orifice. Echo signals passed by the wall filter are Doppler processed and used to quantify the flow through the regurgitant orifice.

Wall filter for ultrasonic mitral regurgitation analysis

An ultrasonic diagnostic imaging system is described which quantifies regurgitant flow through a mitral valve, including the automatic indication of the location of a regurgitant orifice in an ultrasound image. A clinician images the regurgitant valve and indicates in the image the presumed location of the regurgitant orifice (). A flow quantification processor is responsive to this initial location estimate by the clinician to calculate a refined estimation of the orifice location. The refined location is indicated on the ultrasound image by the imaging system, either by relocating an icon placed by the clinician, or displaying a second icon () on the image at the refined location.

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Wayland, MA, United States of America

Qifeng Wei