Steinert Roger F, Schafer Mark E
Department of Ophthalmology, University of California, Irvine, Irvine, California 92651-4375, USA.
J Cataract Refract Surg. 2006 Feb;32(2):284-7. doi: 10.1016/j.jcrs.2005.09.025.
To evaluate and compare ultrasonic turbulence created by conventional and micropulse ultrasound technology.
Sonora Medical Systems, Longmont, Colorado, USA.
A high-resolution digital ultrasound probe imaged the zone around a phacoemulsification tip. Doppler analysis allowed determination of flow. The fluid velocity was measured at 4 levels of ultrasound power at a constant flow, comparing the ultrasonic conditions of continuous energy to WhiteStar micropulses.
In addition to the normal baseline irrigation and aspiration, fluid movement was detected directly below the phaco tip, produced by a nonlinear effect known as acoustic streaming. Acoustic streaming increased with increased phacoemulsification power for both conditions. At each of the 4 levels of power, fluid velocity away from the tip was less with micropulse technology than with continuous phacoemulsification.
The demonstrated decrease in acoustic streaming flow away from the phaco tip with Sovereign WhiteStar micropulse technology compared to conventional ultrasound provides an objective explanation for clinical observations of increased stability of nuclear fragments at the tip and less turbulence in the anterior chamber during phacoemulsification. This methodology can be used to examine and compare fluid flow and turbulence under a variety of clinically relevant conditions.
评估并比较传统超声技术与微脉冲超声技术所产生的超声湍流。
美国科罗拉多州朗蒙特市索诺拉医疗系统公司。
使用高分辨率数字超声探头对超声乳化头周围区域进行成像。通过多普勒分析确定血流情况。在恒定血流状态下,于4个超声功率水平测量流体速度,比较连续能量超声条件与WhiteStar微脉冲超声条件。
除正常的基线冲洗和抽吸外,在超声乳化头正下方检测到由一种称为声流的非线性效应产生的流体运动。两种情况下,声流均随超声乳化功率的增加而增强。在4个功率水平中的每一个水平下,微脉冲技术使远离探头的流体速度低于连续超声乳化技术。
与传统超声相比,Sovereign WhiteStar微脉冲技术所显示的远离超声乳化头的声流减少,为超声乳化过程中核碎片在探头处稳定性增加以及前房内湍流减少的临床观察提供了客观解释。该方法可用于在各种临床相关条件下检查和比较流体流动及湍流情况。