Ultrasonic nonlinear imaging method and ultrasonic nonlinear imaging system

Abstract

The invention discloses an ultrasonic nonlinear imaging system. The ultrasonic nonlinear imaging system comprises a pulse generator and a drive pulse voltage amplifier circuit. By means of quick change of excitation voltage and receiving of echo signals corresponding to drive pulses with quickly changed transmitting voltages, analog-digital conversion is carried out after corresponding gain amplification is completed; the transmitting voltages of the drive pulses and amplifier gains of the corresponding echo signals are proportioned, and echo envelope signals with different excitation voltage gain ratios are firstly subjected to nonlinear preprocessing including depth (time) compensation and the like aiming at nonlinear effect; a nonlinear processing unit obtains the envelope signals after nonlinear preprocessing to generate nonlinear images related to nonlinear acoustic parameter distribution in a tested object by means of operations including logarithm transformation, subtraction and the like. By the ultrasonic nonlinear imaging system, high efficiency in acquisition of nonlinear ultrasonic images higher in image quality can be obtained.

Description

technical field [0001] The invention belongs to the technical field of medicine and relates to an ultrasonic imaging technology, in particular to an ultrasonic nonlinear imaging method and system. Background technique [0002] Ultrasound imaging technology has the advantages of no ionizing radiation, no invasive injury, real-time imaging, and low inspection costs. It has been widely used in clinical diagnosis and treatment. Diagnosis of multiple parts of the body such as breasts and breasts. [0003] For a long time, the theoretical basis of medical ultrasound systems has been a simplified linear acoustic physical model. This model assumes that the emission frequency of the sound source is the only frequency component present in the medium and that an increase in the intensity of the sound source will result in a linear increase in the intensity at any point in the medium. Under these two assumptions, the nonlinear effects of ultrasound are no longer considered. [0004] ...

AI Technical Summary

Problems solved by technology

Not conducive to real-time imaging of medical ultrasound

And the imaging result is a number of variables related to ultrasonic diffraction, scattering, echo formation and nonlinear effects in the object, which cannot accurately reflect the spatial distribution of nonlinear acoustic parameters of the object

The methods of M.Fatemi and J.F.Greenleaf require extremely high-voltage ultrasound excitation pulses, resulting in the MI (mechanical index) of medical ultrasound imaging equipment unable to meet the relevant requirements of human body safety, so it cannot be realized on medical ultrasound imaging systems

Moreover, the ultrasonic waves emitted by medical ultrasonic imaging equipment do not satisfy the assumption of small amplitude signals, which leads to major defects in the imaging principle of this method.

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