Optimization and comparison of a 0.7 mm tip with the 0.9 mm tip on an active-fluidics phacoemulsification platform.

PURPOSE: To assess the effect of varying levels of torsional power on phacoemulsification efficiency using an active-fluidics phacoemulsification platform with a 0.7 mm Sonata tip. SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. DESIGN: Experimental study. METHODS: A 0.7 mm tip was used to emulsify 2.0 mm porcine lenses that had been hardened in formalin. The torsional power was varied from 10% to 100% at intervals of 10%, and efficiency and chatter were recorded. A comparison of the 0.7 mm tip with the 0.9 mm Balanced tip was also performed. Using a torsional power setting of 90% and 100%, the 0.7 mm tip and the 0.9 mm tip efficiency times were recorded. RESULTS: The study showed an increase in efficiency as torsional power increased. The relationship was linear and more efficient up to 90% (R2 = .8025, P = .0005). Chatter was only observed at a torsional power setting of 60%. In addition, a head-to-head comparison of the 0.7 mm tip with the 0.9 mm tip showed that both tips were statistically similar in efficiency times, despite the smaller diameter of the 0.7 mm tip. CONCLUSIONS: The optimum torsional power setting with the Centurion platform in conjunction with the 0.7 mm tip was 90%. The efficiency of the 0.7 mm tip and the 0.9 mm tip was statistically similar.

Comparison of a torsional and a standard tip with a monitored forced infusion phacoemulsification system.

PURPOSE: To compare the relative efficiency and chatter of the 30-degree 0.9 mm Kelman tip (standard tip) and Ozil Intrepid Balanced tip (torsional tip) with identical optimum settings. SETTING: John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. DESIGN: Experimental study. METHODS: Porcine nuclei were fixed in formalin and cut into 2.0 mm cubes. Lens cubes were phacoemulsified with standard and torsional tips at 60% and 100% torsional amplitude with 0%, 25%, 50%, 75%, and 100% longitudinal power with monitored forced infusion. Experiments were performed at a constant vacuum, aspiration rate, and intraocular pressure. RESULTS: Linear regression showed increased efficiency with up to 75% longitudinal power at 60% torsional amplitude for both tips (P = .046 standard; P = .0093 torsional). Longitudinal did not significantly increase efficiency at 100% torsional power for either tip. Torsional tips were on average 29% more efficient than standard tips throughout the range tested (P < .0001), and 100% torsional power was on average 45% more efficient than 60% torsional power (P = .0028). Chatter was minimal except at 100% longitudinal power, which was greater than at 75% longitudinal power (P < .0001). At 100% longitudinal power, torsional tips had more chatter than standard tips (at 60% torsional, P < .0001; at 100% torsional, P = .0022). CONCLUSIONS: Increasing up to 75% longitudinal power increased the efficiency at 60% torsional for standard and torsional tips. Torsional tips were more efficient than standard tips. Chatter was generally minimal. Torsional tips showed more chatter than standard tips at 100% longitudinal power. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.