Daily Wear Contact Lenses Manufactured in Etafilcon A Are Noninferior to Two Silicone Hydrogel Lens Types With Respect to Hypoxic Stress

作者：Szczotka Flynn Loretta B^*; Debanne Sara; Benetz Beth Ann; Wilson Tawnya; Brennan Noel

来源：Eye and Contact Lens: Science and Clinical Practice , 2018, 44(3): 190-199.

DOI：10.1097/ICL.0000000000000335

• Etafilcon A
• Corneal swelling
• Limbal hyperemia
• Endothelial blebs
• Hypoxic stress

Purpose: This study hypothesized that a traditional high-water contact lens of moderate oxygen transmissibility (Dk/t) is noninferior to common silicone hydrogel (SH) lenses worn for daily wear with respect to measures of hypoxic stress.
Methods: Thirty-six habitual contact lens wearers completed wear of three lens types worn in a randomized order: etafilcon A (ACUVUE 2, control), lotrafilcon B (Air Optix Aqua), and comfilcon A (Biofinity). Central corneal thickness (CT) and limbal hyperemia were measured >2 hr after waking and after 6 to 8 hr of wear on days 1 and 7. Endothelial bleb formation was measured on day 1 of each lens type. Noninferiority of etafilcon A, with respect to the other two lens types, was assumed if the following difference margins of equivalence were met: <1.5% for corneal swelling, <0.5 grade for limbal hyperemia, and <1% area of endothelial blebs. Outcomes were modeled using generalized linear mixed modeling techniques.
Results: All lenses showed reductions in least-square mean estimates of CT on both days: etafilcon A -0.26% at day 1 and -0.31% at day 7; lotrafilcon B -1.11% at day 1 and -1.06% at day 7; comfilcon A -0.63% at day 1 and -0.84% at day 7. The difference in mean swelling between etafilcon A and lotrafilcon B was 0.85% at day 1 (95% confidence interval [0.4%-1.3%]) and 0.75% at day 7 (0.3%-1.2%). The difference in mean swelling between etafilcon A and comfilcon A was 0.37% at day 1 (-0.1% to 0.8%) and 0.53% at day 7 (0.1%-1.0%). For limbal redness, etafilcon A fell within 0.1 grade of lotrafilcon B and 0.18 grade of comfilcon A. For endothelial bleb formation, etafilcon A fell within 0.45% of lotrafilcon B and 0.23% of comfilcon A.
Conclusion: The etafilcon A control lens resulted in corneal deswelling throughout the day as did the SH lens types. Limbal hyperemia and endothelial bleb formation with all lenses were negligible, and non-inferiority assumptions were met between the lens types for all outcomes. Equivalence of etafilcon A with respect to the two SH lenses for three measures of hypoxic stress was demonstrated.

• 出版日期2018-5