A recent study compared the comfort and visual performance of corneal rigid gas permeable (GP) and scleral GP contact lenses in participants with corneal ectasia. Using a subjective perception of comfort score (SPC), the researchers found that participants experience better comfort in sclerals than in corneal contact lenses. Still, they noted significantly higher comfort in corneal contact lenses in those who preferred corneal lenses than those who preferred sclerals.
All other outcomes, such as best-corrected visual acuity and contrast sensitivity, exhibited no significant difference between the two types of lenses. They also found no significant difference in the proportion of patients who preferred corneal GPs and sclerals (53% and 47%, respectively). There are unlikely to be any significant visual or visual quality-of-life advantages in refitting successful corneal lens wearers who have keratoconus or other corneal ectasia disorders with scleral lens and vice versa, the researchers noted.
No participant with SPC less than seven out of 10 chose to remain in corneal GPs. The researchers suggest that these individuals may benefit from alternative contact lenses, such as sclerals, even if no other clinical indications for refitting are present.
“If these findings are replicated and validated, the SPC instrument may be used routinely to establish whether an alternative contact lens management may be appropriate to further improve the contact lens experience of successful corneal lens wearers,” the study concluded.
|Levit A, Benwell M, Evans BJW. Randomised controlled trial of corneal vs. scleral rigid gas permeable contact lenses for keratoconus and other ectatic corneal disorders. January 7, 2020. [Epub ahead of print].|