Oki Kotaro
Oki Eye Surgery Center, Tokyo, Japan.
J Cataract Refract Surg. 2004 Aug;30(8):1759-67. doi: 10.1016/j.jcrs.2003.12.035.
To measure and photograph rectilinear flow generated in an anterior chamber model during different power phases of phacoemulsification.
Oki Eye Surgery Center, Tokyo, Japan.
An ultrasound (US) needle was fitted to a Sovereign WhiteStar (AMO) phacoemulsification unit. The sleeved needle was inserted into a silicone test chamber filled with balanced salt solution with glutation (BSS Plus). An LV-1610 laser Doppler vibrometer (Ono-Sokki) captured and processed the velocity and displacement of vibrations on the surface of the test chamber. Measurements were processed in a CF-520 Fast Fourier Transform (FFT) analyzer with the results shown in real time on the FFT analyzer and displayed on a computer monitor using 3-dimensional software. Four US delivery modes were measured: WhiteStar DB, WhiteStar CF, continuous mode, and short-pulse mode at 6 pulses per second (pps). Flow and vacuum were set at 20 cc/min and 200 mm Hg, respectively, and US power was 20% and 50%. Schlieren photography of the fluid flow was performed with an ultra-high-speed Memrecam fx 6000 camera (NAC Image Technology).
The peak vibration velocity (m/s) and displacement at the distal end of the test chamber were greatest for continuous mode, followed by short pulse (6 pps), WhiteStar DB, and WhiteStar CF, in descending order. At 20% power, the US needle generated a peak velocity of 8.64 x 10(-3) m/s in continuous mode, 7.30 x 10(-3) m/s in short-pulse mode, 5.03 x 10(-3) m/s in DB mode, and 3.74 x 10(-3) m/s in CF mode. At 50% power, the US needle generated a peak velocity of 12.8 x 10(-3) m/s in continuous mode, 10.9 x 10(-3) m/s in short-pulse mode, 8.52 x 10(-3) m/s in DB mode, and 6.37 x 10(-3) m/s in CF mode. Schlieren photography showed the greatest wave speed, intensity, and turbulence in continuous mode and the least with the WhiteStar modes.
Peak vibration velocity and amplitude of displacement were less with the WhiteStar delivery modes than with continuous power or short-pulse modes. A similar reduction was seen in the rectilinear flow under Schlieren photography. Attenuation of rectilinear flow and turbulence patterns may have clinical implications for the corneal endothelium during phacoemulsification.
测量并拍摄白内障超声乳化不同能量阶段在前房模型中产生的直线流。
日本东京冲眼科手术中心。
将超声（US）针头安装到Sovereign WhiteStar（AMO）白内障超声乳化仪上。将带套管的针头插入充满含谷胱甘肽平衡盐溶液（BSS Plus）的硅胶测试腔中。LV - 1610激光多普勒振动计（小野测器）捕获并处理测试腔表面振动的速度和位移。测量在CF - 520快速傅里叶变换（FFT）分析仪中进行，结果实时显示在FFT分析仪上，并使用三维软件显示在计算机显示器上。测量了四种超声能量输出模式：WhiteStar DB、WhiteStar CF、连续模式和每秒6脉冲（pps）的短脉冲模式。流量和真空度分别设置为20 cc/min和200 mmHg，超声能量为20%和50%。使用超高速Memrecam fx 6000相机（NAC图像技术公司）对流体流动进行纹影摄影。
测试腔远端的峰值振动速度（m/s）和位移，连续模式最大，其次是短脉冲（6 pps）、WhiteStar DB和WhiteStar CF，依次递减。在20%能量时，超声针头在连续模式下产生的峰值速度为8.64×10⁻³ m/s，短脉冲模式下为7.30×10⁻³ m/s，DB模式下为5.03×10⁻³ m/s，CF模式下为3.74×10⁻³ m/s。在50%能量时，超声针头在连续模式下产生的峰值速度为12.8×10⁻³ m/s，短脉冲模式下为10.9×10⁻³ m/s，DB模式下为8.52×10⁻³ m/s，CF模式下为6.37×10⁻³ m/s。纹影摄影显示连续模式下波速、强度和湍流最大，WhiteStar模式下最小。
WhiteStar能量输出模式下的峰值振动速度和位移幅度低于连续能量或短脉冲模式。在纹影摄影下直线流也有类似的降低。直线流和湍流模式的减弱可能对白内障超声乳化术中角膜内皮有临床意义。
