Researchers at ARVO’s annual meeting presented a study where they measured corneal thickness after short-term small- and large-diameter scleral lens wear.

Twenty healthy participants (15 females and five males, average age 29) were divided into two groups to measure change in corneal thickness after wear of either a 15.2mm or 18mm lens for one hour. Central corneal thickness was measured using the Pentacam both prior to lens wear and immediately after removal.

After an hour of small-diameter lens wear, cornea thickness increased by 1.2%; for those in the large-diameter lens group, the increase was 2.4%. Next, subjects switched to the other modality for one hour. Small-lens wearers had an additional 1.4% increase in corneal thickness after the  change. Those that wore the large lens initially and then wore the small lens experienced a 1% increase.

“There is concern that scleral lens wear may cause the cornea beneath the lens to swell,” the authors noted in their presentation. They also noted that differences in lens diameter and design may influence the cornea physiology differently.