Abstract
Purpose :
To evaluate the postoperative rotational stability of four prototype intraocular lenses (IOLs) featuring unique haptic designs against a control design.
Methods :
Three prospective, multicenter, contralateral-eye studies with 6-month follow-up were conducted to evaluate four test IOL designs against a control. Each test design had a unique, frosted and squared haptic geometry, while the control had the same haptic design as the TECNIS toric IOL. In the first two studies, subjects were contralaterally implanted with test and control IOLs, whereas in the third study, two test designs were contralaterally implanted and their performance was compared to data for the control IOL from the earlier trials. To precisely assess IOL orientation and subsequent rotation, operative photographs were taken at the end of surgery. Postoperative photographs were taken at 1 day, 1 week, 1 month and 6 months postoperative. Paired operative and postoperative photographs were analyzed by two independent, masked analysts to determine the change in lens orientation at each postoperative timepoint. For each IOL, the mean absolute rotation, and frequency of rotations >5° and >10° were calculated. Absolute rotation data were analyzed using a mixed model ANOVA with adjustment for unequal variance.
Results :
At 1 week postoperative, mean (±SD) absolute rotation was 0.81±0.76°, 1.06±1.14°, 0.88±0.94° and 0.71±0.69° for test IOLs 1 through 4, respectively, and 2.26±3.15° for the control IOL (based on pooled data from the first two studies). The difference in mean absolute rotation between test and control was statistically significant for all test IOLs (all p<0.0001). None of the eyes implanted with test IOLs had rotation >5° at 1 week postoperative, except for 1 out of 59 eyes (1.7%) implanted with the test 2 IOL, where rotation was 6.1°. For the control IOL, 10.4% (18/173) of eyes had rotation >5° and 3.5% (6/173) had >10° at 1 week. The signed rotation at 1 day, 1 week and 1 month were highly correlated, suggesting most rotation occurred within 1 day postoperative.
Conclusions :
All four prototype IOLs with frosted, squared haptics demonstrated reduced postoperative rotation versus control. The test 4 IOL had the lowest mean absolute rotation at 1 week. This IOL had the same haptic geometry as the current TECNIS toric IOL, however the haptics were frosted, suggesting this minor haptic modification significantly improved rotational stability.
This is a 2020 ARVO Annual Meeting abstract.