Synopsis

1. Objective Evaluation of Surface Drying/Wetting in Two Daily-Disposable Contact Lenses Using Aberrometry Thomas O. Salmon & Sachiko YamadaNortheastern State University Oklahoma College of Optometry Figure 4 Methods Subjects (masked to lens type) wore Biomedics EV lenses for one day and a week later Acuvue Moist. HOAs for one eye (selected at random) per subject were measured at 20 minutes, 1, 3 and 6 hours after insertion using the COAS aberrometer (AMO Wavefront Sciences). We measured HOAs every second for 60 seconds with a blink every 10 seconds. Ten subjects completed the study. We analyzed change in HO RMS (4-mm pupil; orders 3-6) over time, as well as fluctuation (FI) and stability (SI) indices for each lens. HOA change was defined as the difference between each HOA value and the initial HOA value in each 60-second interval. FI was computed by finding the standard deviation of HO RMS values between blinks, then computing the mean for 6 blink intervals. SI was computed by finding the linear slope fitted to HOA values between blinks, then computing the mean for 6 blink intervals. Synopsis Purpose: Compare drying of two daily-disposable contact lenses (Biomedics EV; Acuvue Moist) using aberrometry. Methods: Aberrometry (every second for 60 seconds) was performed over the lenses to assess drying over time. We compared ∆ HO RMS, fluctuation (FI) and stability (SI) indices. Results: The mean ∆ HO RMS, FI and SI were significantly smaller for the Biomedics EV lens. Conclusion: This indicated less drying for the Biomedics EV lens compared to the Acuvue Moist. Introduction A major cause of soft contact lens (SCL) failure is discomfort due to drying. This can be mitigated in daily-wear lenses by adding a wetting agent to the packaging solution. Our purpose was to compare surface drying/wetting of two daily disposable SCLs, the 1day Biomedics EV (ocufilcon D, packaged with MPC, CooperVision Japan) and the 1day Acuvue Moist (etafilcon A, packaged with PVP, Vistakon). Using serial aberrometry, Koh (IOVS 2008) and others demonstrated that ocular surface drying is associated with an increase in fluctuation, instability and magnitude of higher aberrations (HOAs). We employed this method to compare drying/wetting of these SCLs. Table 2 • Results • Displayed are the mean results averaged across 10 eyes. • After the blink, HOAs increased until the next blink, which provided a partial but incomplete recovery (Fig 1). • The HOA increase was not significantly greater after 6 hours of wear (Fig 2). • The mean increase in HO RMS, FI and SI were signifi-cantly smaller for the Biomedics EV lens (Figs 3,4; Table 2) • Conclusion • Increase in HO RMS indicated drying and tear break up. • The pattern was similar for each SCL for up to 6 hours. • Averaged across subjects and measurement times, the ∆ HOA RMS, FI and SI were significantly smaller for the Biomedics EV compared to the Acuvue Moist. • This indicates less drying or tear break up over time for the Biomedics EV compared to the Acuvue Moist. • This may have been due to differences in material, the storage solution or both. Table 1 - Subjects (3 male, 8 female) Figure 3 Figure 1 Figure 2 ARVO 2009 - Hall B/C; Session 528; Poster board #D959; Thursday, May 7, 8-10:15 AM