基于回波幅值信号的医用超声探头性能快速检测系统的研制

Development of Rapid Performance Testing System for Medical Ultrasonic Probes Based on Echo Amplitude Signal

目的研制一套基于回波幅值信号的医用超声探头阵元快速检测系统,用以对超声探头性能进行评估与质量控制。方法运用现场可编程门阵列作为系统主控制芯片,以控制系统内部集成的电脉冲激励信号源,进而激励医用超声探头的阵元。阵元振动后产生超声波并在遇到空气后反射。基于超声脉冲回波测试方法,以回波幅值为主要检测参数,实现对超声探头阵元工作状态的检测与评估。结果选取同型号不同使用年限及故障状态的探头进行系统测试,并与所成超声图像进行对比:全新完好探头的回波幅值信号范围为550~575 mV,整体误差小于0.5 dB;使用1年的探头回波幅值信号范围为550~590 mV,较全新探头整体误差低0.6 dB左右;使用3年的探头回波幅值信号中存在十多个3 dB、6 dB及个别10 dB等不同程度的衰减;故障探头中存在三十多个成片连续衰减10 dB阵元。探头衰减位置及程度与所成超声图像缺损位置及程度相对应。结论本系统具有灵敏度高、稳定性好、操作简单快速等特点,在超声探头阵元性能评估方面具有很强的实际应用和推广价值。

Objective Aim to develop a rapid performance testing system for medical ultrasonic probe array element based on echo amplitude signals,to evaluate the performance and quality control of ultrasonic probes.Methods The field programmable gate array was used as the main control chip of the system to control the integrated electric pulse excitation signal source inside the system,thereby to stimulate the array elements of medical ultrasonic probes.After the vibration of the array element,ultrasonic waves were generated and reflected when encountering air.Based on the ultrasonic pulse echo testing method,the echo amplitude was the main detection parameter to achieve the detection and evaluation of the working state of the ultrasonic probe array element.Results Selected probes of the same model with different service life and fault status for system testing and compared them with the obtained ultrasound images.The echo amplitude signal of the brand new intact probe was concentrated between 550 mV and 575 mV,with an overall error of less than 0.5 dB.The echo amplitude signal of the probe used for one year was concentrated between 550 mV and 590 mV,which was about 0.6 dB lower than the overall error of the new probe.There were varying degrees of attenuation in the amplitude signal of the probe echo after 3 years of use,such as more than ten 3 dB,6 dB,and some 10 dB.There were more than thirty continuously attenuated 10 dB array elements in the faulty probe.The attenuation position and degree of the probe correspond to the defect position and degree of the resulting ultrasound image.Conclusion This system has the characteristics of high sensitivity,good stability,simple and fast operation,and has strong practical application and promotion value in the performance evaluation of ultrasonic probe array elements.