Looking into the effects of scleral lens wear on patients with ocular surface disease, researchers recently found a statistically significant increase in central corneal thickness (CCT), but did not detect a significant relationship between scleral lenses and intraocular pressure (IOP). They attributed the CCT changes to potential corneal edema caused by a subclinical hypoxic condition stemming from scleral lens wear.
This retrospective study evaluated 46 eyes of 25 subjects fit with scleral lenses ranging in diameter from 17.0mm to 18.0mm. The patients were categorized into the following groups based on the etiology of their dry eye: chronic graft-vs.-host disease, Stevens-Johnson syndrome, Sjögren’s syndrome or general dry eye syndrome. CCT and IOP measurements were obtained at the initial scleral lens consultation and at follow-up visits immediately after lens removal.
The team discovered that the average differences were 7.19mm between pre- and post-lens wear CCT—a statistically significant increase of 1.01%—and -0.89mm Hg between pre- and post-lens wear IOP. They add that there were no statistically significant correlations between CCT or IOP changes and: visual acuity, lens diameter, dry eye etiology or wearing time.
Although scleral lens wear doesn’t seem to affect IOP in healthy young eyes, the study authors recommend exercising caution when fitting older patients with these lenses.
“The concern for elevated IOP and glaucoma development is valid, especially when considering the role that CCT plays as a risk factor for glaucoma,” the researchers concluded in their paper.
|Shahnazi KC, Isozaki VL, Chiu GB. Effect of scleral lens wear on central corneal thickness and intraocular pressure in patients with ocular surface disease. Eye Contact Lens. October 24, 2019. [Epub ahead of print].|