Acoustic Imaging Technologies Corp.

Michael R Sturgill

Bradley K Herres, Deceased

Richard H Love

Marsha A Thesen

Theodore F Herres, Executor

Muriel Herres, Executor

An ultrasonic blood flow measuring and imaging system comprises a transmit-receive transducer for transmitting ultrasonic waves toward and into the human body and for receiving reflected echo signals which are then processed for use in a Doppler blood flow imaging and display system. Multiple ultrasonic pulse beams are transmitted into the body at each of a number of angles in an area under diagnosis. For each angle, a plurality of reflected echo signals are received during successive predetermined time intervals. Each received echo signal has a stationary component reflected from essentially stationary tissue and a Doppler component reflected from areas where movement is sensed, such as blood flow. The reflected echo signals are processed in an MTI filter subtracting a stationary component from the received echo signals to thereby extract a Doppler signal representative of a Doppler component of the received echo signals. The Doppler component is then processed in an MTI filter equalizer having a frequency response which is the inverse of the MTI filter, for producing an output having an essentially flat frequency response over the range of frequencies being measured. The output is used to produce color flow imaging of the blood flow in the area under diagnosis.

Ultrasonic Doppler imaging systems with improved flow sensitivity

An ultrasonic blood flow measuring and imaging system comprises a transmit-receive transducer for transmitting ultrasonic pulses toward and into the human body and for receiving reflected echo signals which are then processed for use in a Doppler blood flow imaging and display system. Multiple ultrasonic pulses are transmitted into the body at each of a number for angles in an area under diagnosis. For each angle, a plurality of reflected echo signals are received during successive predetermined time intervals. Each received echo signal has a tissue motion Doppler component representative of reflection from moving tissue and a blood flow Doppler component representative of relfection from both moving tissue and flowing blood. The reflected echo signals are processed in a system which includes tissue velocity determining elements for estimating the velocity of the tissue motion, and tissue velocity canceller elements for removing a tissue velocity component from the received echo signals. The system provides output signals used to produce color flow imaging of the blood flow in the area under diagnosis.

Adaptive tissue velocity compensation for ultrasonic Doppler imaging

A system for improving the flow estimation sensitivity of an ultrasonic Doppler flow imaging system includes an ultrasonic wave tranmitter and receiver for sequentially transmitting ultrasonic waves toward and into a living body and for receiving the reflected Doppler-shifted echo signals. A series of echo signals received from each of a number of points within the body are processed in a velocity estimator, using maximum entropy techniques, to produce an output signal representative of an estimated velocity of the flow at each of said points within the body. The processing means detects the series of echo signals for each point and calculates an average power spectrum based on the amplitude-versus-frequency distribution of the series of received echo signals. The power spectrum is calculated by fitting a first order polynomial to the series of echo signals, although higher order polynomials can be used. A peak center frequency shift associated with the data detected for each point is derived from the power spectrum. The resulting peak center frequency shift information is then processed to produce a velocity estimate for each of the points at which velocity is being measured, and the resulting velocity estimate information is then processed further for imaging in a two-dimensional Doppler color flow imaging display.

Growing community of inventors

Phoenix, AZ, United States of America

Michael R Sturgill