Translenticular hydrodissection, lens fragmentation, and influence on ultrasound power in femtosecond laser-assisted cataract surgery and refractive lens exchange

PURPOSE: To compare ultrasound time (UST) during femtosecond laser assisted and conventional cataract surgery or refractive lens exchange and evaluate UST during femtosecond laser surgery with and without a new technique, translenticular hydrodissection. SETTING: Centre for Sight, East Grinstead, West Sussex, United Kingdom. DESIGN: Comparative case series. METHOD: This single-surgeon study compared consecutive femtosecond laser assisted surgery (with and without translenticular hydrodissection to assist lens mobilization) and consecutive conventional surgery performed immediately before adoption of femtosecond laser technology. The mean US power, UST, and effective phacoemulsification time (EPT) in the 2 groups were compared. Further analysis of the femtosecond group compared translenticular hydrodissection and no translenticular hydrodissection. RESULTS: The mean US power, UST, and EPT were significantly longer in the conventional group (n = 108) than in the femtosecond group (n = 108) as follows: 7.30% +/- 2.56% (SD) versus 5.32% +/- 2.48% (P=.000); 9.89 +/- 5.32 seconds versus 8.58 +/- 4.66 seconds (P=.044); 0.87 +/- 0.85 seconds versus 0.57 +/- 0.51 seconds (P=.002), respectively. In the femtosecond group, parameters were significantly higher in eyes without translenticular hydrodissection (n = 27) than in eyes with translenticular hydrodissection (n = 81) as follows: 5.78% +/- 2.23% versus 5.16% +/- 2.56% (P=.046); 10.95 +/- 4.66 seconds versus 7.78 +/- 4.41 seconds (P=.046); 0.72 +/- 0.26 seconds versus 0.52 +/- 0.53 seconds (P=.002), respectively. CONCLUSION: Femtosecond laser capsulotomy and lens fragmentation statistically significantly reduced UST over conventional surgery. Trans lenticular hydrodissection further reduced UST.