Display for subtraction imaging techniques

A method to visualize tissue background and low amplitude signals simultaneously, without restricting visualization of the low amplitude signals, the method comprising:

• creating a first image from a plurality of firings at a target to form corresponding waveforms;
• processing said waveforms to form said first image, wherein said first image is indicative of the low amplitude signal;
• displaying said first image on a display device;
• creating a second image from a subset of said plurality of firings to form a subset of said corresponding waveforms;
• processing said subset of said corresponding waveforms, wherein said second image is a B-mode image indicative of the tissue background proximate the flow signal;
• and
• displaying said second image on said display device.

A method of operating an imaging system comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and transducing returned wave energy into electrical signals, and a display monitor for displaying a image having a first image portion which is a function of a flow image signal and having a second image portion which is a function of a reference image signal, said method comprising:

• (a) activating transducer elements of said array to transmit focused wave energy encoded with a transmit code during first and second transmit events;
• (b) forming first and second receive signals from electrical signals produced by said transducer elements subsequent to said first and second transmit events respectively;
• (c) forming a reference image signal derived at least in part from independent processing of at least one of said first and second receive signals;
• (d) compressing, bandpassing and wall filtering first and second fundamental signal components of said first and second receive signals respectively to form a flow signal;
• (e) forming a flow image signal derived at least in part from said flow signal;
• and
• (f) applying said flow image signal and said reference image signal to the display monitor, wherein said reference image is adjustable without affect to said flow image.

A method of operating an imaging system comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and transducing returned wave energy into electrical signals, and a display monitor for displaying an image having an image portion which is a function of a flow image signal, said method comprising of:

• (a) activating transducer elements of said array to transmit focused wave energy encoded with a first Golay code of a Golay code pair during first and third transmit events and to transmit focused wave energy encoded with a second Golay code of said Golay code pair during second and fourth transmit events;
• (b) forming first through fourth receive signals from electrical signals produced by said transducer elements subsequent to said first through fourth transmit events respectively;
• (c) forming a reference image signal derived at least in part from independent processing of two of first through fourth receive signals;
• (d) decoding, bandpassing and wall filtering first through fourth fundamental signal components of said first through fourth receive signals respectively to form a flow signal;
• (e) forming a flow image signal derived at least in part from said flow signal;
• and
• (f) applying said flow image signal and said reference image signal to the display monitor, wherein said reference image is adjustable without affect to said flow image.

An ultrasound medical diagnostic system for imaging stationary and moving reflectors for an area of interest in a patient, comprising:

• a transmitter for transmitting a sequence of at least two pulses to a transmit focal position;
• a receiver for receiving at least two echo signals associated with said sequence of at least two pulses, said echo signals containing a fundamental frequency component;
• a first display processor configured to receive and process said at least two echo signals and having a filter for supplying a filtered signal containing flow image information for moving reflectors based on said at least two echo signals,
• a second display processor configured to receive and independently process at least one of said at least two echo signals containing B-mode information for stationary reflectors based on said at least two echo signals, said B-mode information for stationary reflectors including said fundamental frequency component;
• and
• a display for displaying a flow image of moving reflectors based on said filtered signal and a B-mode reference image of stationary reflectors based on said at least one of said at least two echo signals supplied by said second display processor.

An imaging system comprising:

• a transducer array having a multiplicity of transducer elements for transmitting wave energy centered at a fundamental frequency in response to electrical activation and for transducing returned wave energy into electrical signals;
• a display monitor for displaying an image having a first image portion which is a function of a flow image signal and a second image portion which is a function of a B-mode reference image signal;
• and
• a computer programmed to perform:
• (a) activating transducer elements of said array to transmit focused wave energy encoded with a transmit code during first and second transmit events;
• (b) forming first and second receive signals from electrical signals produced by said transducer elements subsequent to said first and second transmit events respectively;
• (c) processing at least one of said first and second receive signals to form a B-mode signal;
• (d) compressing, bandpassing and wall filtering first and second fundamental signal components of said first and second receive signals respectively to form a flow signal;
• (e) forming a B-mode reference image signal derived at least in part from said B-mode signal;
• (f) forming a flow image signal derived at least in part from said flow signal;
• and
• (g) applying said B-mode image signal and said flow image signal to said display monitor.