Torsional power study using CENTURION phacoemulsification technology

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 mmHg, aspiration to 50 ml/min, and intraocular pressure at 50 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 2  = .90; P  < 0.05). There were no significant differences in efficiency past 60%. Chatter was highest at 10% power and decreased linearly ( R 2  = .87; P  = 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