Comfort remains the key factor in maintaining contact lens satisfaction among patients. While numerous product developments have significantly improved the wearing experience over the last few decades, comfort considerations and improvement continue to be of substantial interest to eye care professionals and consumers.
Furthering the eye health profession’s scientific understanding of contact lens comfort factors, CooperVision revealed findings from multiple studies it has conducted, in partnership with research centres and experts across various fields, at the annual 2022 Association for Research in Vision and Ophthalmology (ARVO) meeting in Denver, United States in early May.
Two of the studies presented1,2 were focussed on helping protect the ocular surface from hyperosmolarity of the tear film, which has particular relevance for contact lens wearers who are symptomatic, especially those with dryness. Conducted with the Herbert Wertheim School of Optometry & Vision Science at the University of California, Berkeley, the research team designed and employed a novel model to quantify a non-measurable yet critical factor: tear film osmolarity behind a contact lens.
“We concluded that contact lens materials with low salt diffusivity are better at protecting the cornea from hyperosmolarity and that osmolarity behind a contact lens reaches a steady state within the first hour. Our findings also illustrate that midday lens removal and reinsertion alone cannot prevent post-lens tear film hyperosmolarity,” said Cheng-Chun Peng, a Senior Scientist at CooperVision who coauthored the ARVO-delivered paper and poster.
“If tear film break-up on the cornea is believed to cause discomfort, contact lenses could theoretically help protect the ocular surface from osmolarity spikes. While pre-lens tear film hyperosmolarity is primarily due to evaporation, little is known about salt accumulation within and behind a contact lens. A better understanding of this factor could lead to substantial gains in future lens innovations and patient care.”
Additional CooperVision comfort science presented at ARVO 2022 included research regarding corneal sensitivity changes in symptomatic neophyte contact lens wearers,3 an evaluation of discomfort-associated conjunctival epithelial cell gene expression,4 and preliminary results from the Neurosensory Abnormalities in Ocular Surface Disease study.5 Those projects were conducted in conjunction with Indiana University, Universidad de Valladolid, and Tufts Medical Centre, respectively.
“Our commitment to comprehending the scientific fundamentals of contact lens comfort run deep, many of which relate to the eye’s physiological responses to wear. By partnering with renowned research centres and experts across various fields… we draw closer each day to unlocking the secrets of even greater patient and practitioner satisfaction,” said Nancy Keir, OD, PhD, Senior Director, Program and Biological Sciences for CooperVision.
- Kim Y, et al. Protection Against Localized Corneal Hyperosmolarity Spikes with SCL Wear. ARVO 2022 paper presentation.
- Radke C, et al. Dynamic Salt Accumulation in PLTF with SCL Wear: Implications for Protection Against Corneal Hyperosmolarity. ARVO 2022 poster presentation.
- Situ P, et al. Changes of Corneal Sensitivity in Symptomatic Neophyte Contact Lens Wearers. ARVO 2022 poster presentation.
- Calderón-García A, et al. Evaluation of Gene Expression in Conjunctival Epithelial Cells Associated to Contact Lens Wear and Discomfort. ARVO 2022 poster presentation.
- Hom M et al. Comparison of Ocular Surface Disease Patients within Two Different Clinical Settings: Preliminary Results from Neurosensory Abnormalities in Ocular SurfAce Disease (NASA) Study. ARVO 2022 poster presentation.