白内障超声乳化仪中手柄频率跟踪方法的研究  

Ultrasound handle frequency tracking method for cataract phaco-emulsifier

作　　者：巩丽文[1] 杨军[1] 纪运红[1] 

机构地区：[1]中国医学科学院北京协和医学院生物医学工程研究所,天津300192

出　　处：《生物医学工程与临床》2011年第6期517-520,共4页Biomedical Engineering and Clinical Medicine

基　　金：天津市自然科学基金资助(09ZXCXSF03100)

摘　　要：目的通过对谐振网络幅频特性的分析,提出一种白内障超声乳化仪中跟踪手柄谐振频率的新方法。方法谐振网络等效负载阻抗两端电压随激励信号的频率而变化,当激励信号的频率等于超声手柄的谐振频率时,电压取得最小值。利用谐振网络这一幅频特性,在扫频过程中,通过寻找其电压最小值来确定超声手柄的谐振频率。在超声乳化仪工作时,实时检测谐振网络两端的电压并不断微调激励信号的频率,使电压始终保持最小值,从而达到频率跟踪的目的。结果扫频取得的幅频特性曲线中,电压最小值所对应的频率为手柄谐振频率,该值处手柄尖端振幅最大。频率跟踪方法能够随谐振网络阻抗及负载力的变化而迅速跟踪谐振频率,且跟踪过程平稳可靠。结论实验研究表明,该方法可有效地实现动态频率跟踪,提高了超声乳化仪的功率输出效率,保证了白内障手术高效安全地进行。Objective To study a new method of tracking ultrasound handle resonant frequency for ophthalmic cataract phacoemulsifier through analyzing amplitude-frequency characteristics in resonant network.Methods The voltage across the equivalent load impedance of resonant network was changed with frequency of excitation signal.The voltage reaches to the minimum value as the frequency of excitation signal was equaled with the resonant frequency of ultrasound handle.The resonant frequency of ultrasound handle could be determined by searching the minimum voltage in sweeping process.As the phaco emulsifier worked,the voltage was kept at the minimum value by real-time detection and incessant fine-tuning of excitation signal frequency in order to realize the frequency tracking.Results In the amplitude-frequency characteristic curve obtained by sweeping,the frequency corresponding to the minimum voltage was the resonant frequency of handle,and the amplitude at the tip of handle was the maximum value.The frequency tracking method could rapidly track resonant frequency with the changes of network impedance and load force,and the tracking process was smooth and reliable.Conclusion It is demonstrated that the method could effectively implement dynamic frequency tracking,improve the power output efficiency of phaco-emulsifier,and ensure the efficient and safe manner of cataract surgery.

关 键 词：谐振网络 幅频特性 超声乳化仪 频率跟踪 

分 类 号：R318.6[医药卫生—生物医学工程]