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Comparison of torsional and longitudinal modes using phacoemulsification parameters
Marek Rekas1, Robert Montés-Micó, Karolina Krix-Jachym
1Department of Ophthalmology, Military Health Service Institute, Warsaw, Poland. rekaspl@gmail.com
Journal of Cataract and Refractive Surgery
|September 29, 2009
Summary
Torsional ultrasound mode phacoemulsification is more effective than longitudinal mode, using less energy and fluid. This efficiency was consistent across various cataract densities, showing improved outcomes in torsional cataract surgery.
Area of Science:
- Ophthalmology
- Surgical Technology
- Cataract Surgery
Background:
- Phacoemulsification is a standard cataract surgery technique.
- Ultrasound (US) modes, including torsional and longitudinal, are used to emulsify the cataractous lens.
- Optimizing energy delivery and fluid dynamics is crucial for surgical outcomes.
Purpose of the Study:
- To compare the efficiency of torsional versus longitudinal ultrasound modes in phacoemulsification.
- To evaluate key parameters such as phaco time, power, amplitude, and aspiration time.
- To assess total energy expenditure and effective coefficient across different nucleus densities.
Main Methods:
- A prospective study evaluated 400 eyes undergoing phacoemulsification with the Infiniti Vision System.
- Eyes were assessed at 1, 7, and 30 days post-surgery.
- Cataract classification (Lens Opacities Classification System II) and nucleus fragmentation techniques (phaco-chop, quick-chop) were standardized.
Main Results:
- Torsional mode demonstrated significantly lower cumulative dissipated energy (CDE) for nucleus grades I-III.
- Aspiration time was significantly shorter with torsional mode for nucleus grades III and IV.
- Total energy and effective coefficient showed significant advantages for torsional mode across most nucleus densities.
Conclusions:
- Torsional phacoemulsification is more effective than longitudinal mode regarding fluid application and ultrasound energy usage.
- The torsional method allows for a consistent ratio of fluid flow to ultrasound energy, irrespective of nucleus density.
- This suggests improved efficiency and potentially better outcomes with torsional ultrasound in cataract surgery.
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