New, healthy gas permeable (GP) wearers don’t appear to adapt better to lens wear if changes are made to the lens diameter or surface lubricity, a team of researchers from the UK reports.

Their study, published in Contact Lens & Anterior Eye, was a two-part, prospective, double-masked, randomized investigation in which 119 neophyte patients wore, on separate occasions, a GP lens (9.6mm diameter) with a Hydra-PEG (Tangible Science) plasma-coated surface or an uncoated GP lens. Patients were approximately 21 years old, and 77% of the study subjects were female. A second group of 114 age- and gender- matched neophyte wearers wore the uncoated lens with the 9.6mm diameter in one randomly allocated eye. In the other eye, 51 patients wore a 10.1mm diameter lens, and 62 subjects wore a 10.6mm diameter lens with a base curve compensation keeping the fit equivalent.

The researchers assessed lens fit and corneal staining after 20 minutes. Additionally, the investigators noted comfort and bulbar redness at the time of lens application and again after five, 10, 15 and 20 minutes. Participants also reported their ease of application and removal on a five-point scale.

The investigators found neither the plasma coated GP lenses or increasing diameters improved comfort or bulbar redness during the 20-minute adaptation period. In both cohorts, comfort improved and bulbar redness reduced with time. Additionally, corneal staining, ease of insertion and ease of removal did not differ with GP coating or diameter.

Debarun D, Wolffsohn JS. Effect of large diameter and plasma coating on the initial adaptation of gas permeable contact lens fitting for neophytes. Contact Lens Anter Eye. September 8, 2020. [Epub ahead of print].