Torsional power study using CENTURION phacoemulsification technology.

Abstract

BACKGROUND: To evaluate the effect of varying levels of power on phacoemulsification efficiency using the CENTURION Vision System. METHODS: Formalin-soaked porcine lenses were divided into 2-mm cubes; 0.9-mm, balanced tips were used. Torsional power levels were tested from 10% to 100% at 10% intervals. Vacuum was set to 550&#x2009;mmHg, aspiration to 50&#x2009;ml/min, and intraocular pressure at 50&#x2009;mmHg. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined. RESULTS: Increasing torsional power up to 60% increased efficiency. This effect was linear from 30 to 60% power (R&#x2009;=&#x2009;.90; P&#x2009;<&#x2009;0.05). There were no significant differences in efficiency past 60%. Chatter was highest at 10% power and decreased linearly (R&#x2009;=&#x2009;.87; P&#x2009;=&#x2009;0.007) as power was increased up to 60% power, and chatter did not improve above this power level. CONCLUSIONS: Power improved efficiency only up to a 60% power level, and then was negligible. Chatter correlated well with power up to the 60% level, so that as power was increased, chatter decreased. Because there are no additional benefits in efficiency past 60% power, and because chatter is minimal at 60% power, we recommend torsional ultrasound at 60% as the optimal power setting for using the CENTURION System for phacoemulsification.l.