<p>The short-term physiological impact of switching reusable silicone hydrogel wearers into a hydrogel daily disposable multifocal</p>

Abstract

Purpose: To evaluate ocular physiological responses to etafilcon A multifocal (etMF) daily disposable (DD) lenses after 4 weeks of wear, when switching from habitual silicone hydrogel (SiHy) daily wear. Method: A single-arm, open-label, bilateral dispensing study was conducted in 39 habitual spherical SiHy wearers (14 hyperopes; 25 myopes). Clinical visits occurred with habitual SiHy (control) at baseline and after 4 weeks of etMF DD open-eye lens wear at exit. Objective limbal/bulbar hyperemia using the Oculus K5M (0–4) and subjective grading of lid wiper epitheliopathy (LWE) (0–4) were tested for non-inferiority (NI), using a margin of 1 grade. Corneal thickness along a 10 mm cord was measured using the Visante OCT and tested for NI using a 30 μm margin. Corneal staining area was graded (0–100%). Results: The least-square mean differences (LSMD) and 95% confidence interval (95% CI) between etMF DD and habitual SiHy in central and peripheral corneal thickness (μm) were 3.64 (−2.0, 9.29) and 3.0 (−7.72, 13.72) in hyperopic, and 3.56 (−0.66, 7.78) and 6.40 (−1.62, 14.42) in myopic subjects. The LSMD (95% CI) for bulbar and limbal hyperemia were −0.08 (−0.19, 0.02) and −0.01 (−0.12, 0.09) in hyperopes, and 0.04 (−0.03, 0.12) and 0.04 (−0.04, 0.11) in myopes. The LSMD (95% CI) for LWE were 0.11 (−0.39, 0.60) and 0.30 (−0.07, 0.67) for hyperopes and myopes, respectively. Conclusions: No clinically significant differences in a variety of physiological responses were found when habitual reusable SiHy daily wear subjects were refitted into hydrogel etMF, when the subjects were followed for 4 weeks.

Ocular health of children wearing daily disposable contact lenses over a 6-year period

“…This supports other literature that have reported no clinically relevant hypoxic changes with a healthy population wearing hydrogel lenses in a daily wear, daily disposable modality. [42][43][44] Hypoxic changes were not expected because the oxygen transmission through these thin lenses of low/mid myopic powers meets the requirements for daily wear in an adult population, and it is reassuring to see this confirmed within this paediatric population.…”

BCLA CLEAR - Effect of contact lens materials and designs on the anatomy and physiology of the eye

“…This criterion was re-evaluated in a more recent study and determined to be 19.8 and 32.6 Dk/t units, respectively, to avoid average central and peripheral corneal swelling in soft lens daily wear [435]. The results of current short-term studies suggest expecting an average minimal ocular physiological impact in open-eye wear with a minimum central Dk/t ~25 units and peripheral Dk/t of ~11 units [436,437]. It is noteworthy that the suggested minimum Dk/t values for closed or open-eye lens wear can only predict the population average corneal swelling values and are inherently incapable of reflecting individual Dk/t requirements in practice [408].…”

Thirty years of ‘quiet eye’ with etafilcon A contact lenses

“…For daily wear in low to moderate degrees of myopia, there is no evidence to support the need to fit silicone hydrogel lenses, over lower Dk hydrogels, due to concerns around corneal swelling. For example, Moezzi et al [107] reported no clinically significant differences in corneal swelling when habitual, reusable, silicone hydrogel, daily wear subjects were refitted into etafilcon A, multifocal daily disposable lenses and followed for four weeks. Also, Moezzi et al [108] demonstrated no difference in topographical corneal swelling between Acuvue Define lenses and Acuvue Define lenses with Lacreon, versus no lens wear.…”