Optimum on-time duty cycle for a transversal ultrasound machine
| Autor: | Brian Zaugg, Jeff H. Pettey, Alex J. Wright, Randall J. Olson, Ashlie Bernhisel, Brian Ta, Austin Bohner, William R. Barlow |
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| Rok vydání: | 2018 |
| Předmět: |
Time Factors
Swine medicine.medical_treatment Operative Time High-Energy Shock Waves Salt lake 03 medical and health sciences 0302 clinical medicine medicine Animals Ultrasonics Off time Mathematics Phacoemulsification business.industry Ultrasound Significant difference Lens Nucleus Crystalline Sensory Systems Bevel Ophthalmology Duty cycle Transversal (combinatorics) 030221 ophthalmology & optometry Surgery business 030217 neurology & neurosurgery Biomedical engineering |
| Zdroj: | Journal of Cataract and Refractive Surgery. 44:1140-1143 |
| ISSN: | 0886-3350 |
| Popis: | Purpose To evaluate the optimum on-time setting for the most efficient removal of lens fragments using micropulse ultrasound (US) and Ellips FX transversal US in the Whitestar Signature Pro phacoemulsification machine. Setting John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. Design Experimental study. Methods Porcine lens nuclei were soaked in formalin for 2 hours and cut into 2.0 mm cubes. The US machine was used with a bent 0.9 mm phaco tip and a 30-degree bevel. The off time was set to 6 milliseconds (ms) and the on time varied from 4 to 10 ms in 1 ms increments. Efficiency (time for fragment removal) and chatter (number of times the fragment bounced from the tip) were measured. Results A linear incremental increase in efficiency was observed between 4 ms and 6 ms. The most statistically significant efficiency was achieved with an on time of 6 ms. On times shorter than 6 ms were significantly less efficient (P = .05). Greater on times (7 to 10 ms) did not result in a significant difference in efficiency (P = .72), but did appear to have more chatter events when comparing on-time settings of 7 to 10 ms with 4 to 6 ms (P = .02). Conclusions With micropulse transversal US, 6 ms of on time was as efficient as longer on times. To maximize phacoemulsification efficiency and minimize chatter events, an on time of 6 ms is recommended. |
| Databáze: | OpenAIRE |
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