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Updated: Jan 25, 2026

A Microfluidic Device with Groove Patterns for Studying Cellular Behavior
Published on: August 30, 2007
The effect of increasing power when grooving using phacoemulsification
Rhett S Thomson1,2, Brian A Bird3, Lance A Stutz4
1Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, Salt Lake City, UT 84132, USA, jeff.pettey@hsc.utah.edu.
Purpose:
To determine optimal power settings on the Centurion Vision System during the grooving step in cataract surgery.
Methods:
Intact porcine lenses hardened by formalin and placed in a chamber designed to simulate the anterior chamber of the eye were used to test longitudinal power at 40%, 70%, and 100% and torsional power at 0%. Flow rate was set at 40 mL/min. Vacuum was set at 400 mmHg, intraocular pressure was set at 50 mmHg, and a balanced phacoemulsification tip with a 20 degree tip and a 30 degree bevel was used. Efficiency (time to groove the lens in half) was determined.
Results:
Increasing longitudinal power from 40% to 70% increased efficiency by 28% (P<0.05), and by 32% (P<0.05) when increasing longitudinal power from 40% to 100%. There was no statistically significant increase in efficiency from 70% to 100%.
Conclusion:
For the tested variables, a longitudinal power of 70% was determined to be most efficient during the grooving step of cataract surgery for equivalent 3-4+ nuclei. Further increases in power demonstrated no statistically significant improvement in efficiency.
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