Abstract
Purpose :
Torsional oscillation of the phaco tip is increased surgical efficiency in cataract surgery, compares with conventional longitudinal ultrasound (US). Recently improved longitudial US (Stellaris®, Bausch & Lomb, NY, USA) is known as less heat generation and increased phaco efficiency in theoretically. This study tested the hypothesis that the improved longitudial US showed superior efficiency and induced less endothelial cell loss than torsional US for hard cataract.
Methods :
The present study included 44 eyes of 44 patients with hard cataract (nuclear sclerosis grade 4 and 5) undergoing cataract surgery. Operated eyes were compared in terms of the total phacoemulsification (phaco) time, average phaco power, total phaco energy and amount of fluid used during cataract surgery between the 2 modalities. Endothelial cell density, corneal edema, central corneal thickness (CCT), surgically induced astigmatism (SIA) and best-corrected visual acuity (BCVA) were also evaluated preoperatively and up to 3 month postoperatively.
Results :
In patients with hard cataract, the ultrasound time was significantly higher in the torsional group than the longitudinal group (37.08 ± 19.57sec versus 79.81 ± 43.92sec). The total phaco energy was significantly higher in the torsional group (8.58 ± 5.75 versus 23.07 ± 16.48). But, The average phaco power, and amount of fluid were similar between the 2 modalities. The torsional group induced more persistent corneal edema at 1 week postoperatively and more endothelial cell loss at 1 and 3 month postoperatively. Postoperative CCT, SIA and BCVA were not significantly different between the 2 modalities.
Conclusions :
As with our hypothesis, recently improved longitudinal US showed superior efficiency for hard cataracts and induced less endothelial cell loss compared to torsional US.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.