Method for optimization of transmit and receive ultrasound pulses, particularly for ultrasonic imaging
AssigneeEsaote S.p.A.
InventorsAndrea Trucco, Simone Curletto
Life of this patent
Estimating the term…
Abstract
A method for optimizing transmit and receive ultrasound imaging pulses generates transmit pulses from an array of transducers which are energized by excitation signals that are applied to each individual transducer of the array. Each of the excitation signals are individually weighted to optimize the transducers' contribution to a predetermined energy function. Such optimization may also be performed on the received pulses.
Claims64
A method for optimizing ultrasonic pulses, particularly for ultrasound imaging, wherein transmit pulses are generated from ultrasonic pulse contributions of each of a plurality of electroacoustic transducers, said transducers being grouped in an array and being individually triggered by electric excitation signals, said excitation signal being applied to each individual transducer of said array having a predetermined delay with respect to the application of the excitation signal that is applied to the other transducers of said plurality of transducers, and wherein a weight is applied to the excitation signal for each transducer for adjusting the amplitude of said excitation signal, characterized in the following steps:
- defining an optimal desired mechanical pressure profile for said transmit pulses relative to the penetration depth of said transmit pulses within the body or object being examined as a function of at least amplitude weighting parameters for said transducers' contributions to said transmit pulses, and of the delays of excitation for transmission of individual pulse contributions of transducers, aimed at focusing comprehensive pulses on a scan line or band and at a certain penetration depth within the body or object under examination;
- defining an ideal beam pattern for said transmit pulses relative to the propagation time or penetration depth within the body or object under examination as a function of at least amplitude weighting parameters for said transducers' contributions to said transmit pulses, and of delays of excitation delays for transmission of individual pulse contributions of transducers aimed at focusing comprehensive pulses on a scan line or band and at a certain penetration depth within the body or object under examination;
- defining an energy function which depends on the difference between said ideal pressure profile and the actual pressure profile and between said ideal beam pattern and the actual beam pattern;
- determining the minimum of said energy function;
- determining said weighting parameters and said delays which correspond to the minimum of the energy function and applying said weighting parameters and said delays to said excitation signals for exciting said transducers to generate said comprehensive pulses.
A method as claimed in claimed 3, characterized in that said energy function is modified in such manner as to include integration of any excess values of what was actually obtained with respect to what was desired.
A method for optimizing ultrasonic pulses, particularly for ultrasound imaging, wherein receive pulses are generated from ultrasonic pulse contributions of each of a plurality of electroacoustic transducers, said transducers being grouped in an array and being individually triggered by electric excitation signals, said excitation signal being applied to each individual transducer of said array having a predetermined delay with respect to the application of the excitation signal that is applied to the other transducers of said plurality of transducers, and wherein a weight is applied to the excitation signal for each transducer for adjusting the amplitude of said excitation signal, characterized in the following steps:
- defining an optimal desired mechanical pressure profile for said receive pulses relative to the penetration depth of said receive pulses within the body or object being examined as a function of at least amplitude weighting parameters for said transducers' contributions to said receive pulses, and of the delays of excitation for reception of individual pulse contributions of transducers, aimed at focusing comprehensive pulses on a scan line or band and at a certain penetration depth within the body or object under examination;
- defining an ideal beam pattern for said receive pulses relative to the propagation time or penetration depth within the body or object under examination as a function of at least amplitude weighting parameters for said transducers' contributions to said receive pulses, and of delays of excitation delays for reception of individual pulse contributions of transducers aimed at focusing comprehensive pulses on a scan line or band and at a certain penetration depth within the body or object under examination;
- defining an energy function which depends on the difference between said ideal pressure profile and the actual pressure profile and between said ideal beam pattern and the actual beam pattern;
- determining the minimum of said energy function;
- determining said weighting parameters and said delays which correspond to the minimum of the energy function and applying said weighting parameters and said delays to said excitation signals for exciting said transducers to generate said comprehensive pulses.
A method as claimed in claimed 31, characterized in that said energy function is modified in such manner as to include integration of any excess values of what was actually obtained with respect to what was desired.
A transmit ultrasound pulse, characterized in that it is formed by the contributions of individual transducers of a transducer array, which contributions are optimized by using amplitude weights and/or different contribution transmission delays and/or different contribution waveforms, to minimize an energy function and form a comprehensive pulse having a nearly constant mechanical pressure over a predetermined propagation depth range and/or a beam pattern with a narrow and scan line centered main lobe and low side lobes, far from the main lobe, and substantially constant with time, i.e. along the ultrasonic pulse propagation axis.
A receive ultrasound pulse, characterized in that it is formed by the signal contributions of individual transducers of a transducer array, which signal contributions are optimized by using amplitude weights and/or different contribution transmission delays and/or different contribution waveforms, to minimize an energy function and form a comprehensive pulse having a beam pattern with a narrow and scan line centered main lobe and low side lobes, far from the main lobe, and substantially constant with time and/or a nearly constant mechanical pressure over a predetermined propagation depth range, i.e. along the ultrasonic pulse propagation axis.
Dependencies are inferred from the claim text.