Scleral lenses are an old technology that’s seen a resurgence in recent years as new applications are discovered. However, their use may be causing problems for some wearers and, with today’s monitoring capabilities, researchers are uncovering some of the damage, including changes in the posterior corneal curvature and corneal thinning.
The lack of studies evaluating the condition of the posterior corneal curvature following scleral lens application inspired a Spanish research team to undertake the evaluation. The team looked at 26 subjects with keratoconus divided into two groups; one with and one without intrastromal corneal ring segments (ICRS).1 They evaluated corneal thickness in different quadrants, posterior corneal curvature, posterior corneal aberrations and anterior chamber depth—each before and after scleral lens wear.
After eight hours of scleral lens wear, they found statistically significant corneal thinning in the inferior region of the group without ICRS.1 That group also showed a steepening in the temporal quadrant and a flattening that mainly affected the superior-nasal quadrant.1 The ICRS group showed steepening as well, which mainly affected the superior-nasal quadrant.1
Corneal thinning and abnormal curvature is associated with a number of ocular dysfunctions, including blurred vision, nearsightedness, astigmatism and photophobia.2
1. Serramito M, Carpena-Torres C, Carballo J, et al. Posterior cornea and thickness changes after scleral lens wear in keratoconus patients. Contact Lens & Anterior Eye. 2019;42(1):81-91.
2. NEI. Facts about the cornea and corneal disease. nei.nih.gov/health/cornealdisease. May 2016. Accessed January 23, 2019.