• Oral omega-3 fatty acids (O3FA) may have a positive impact on epithelial cell morphology and goblet cell density in contact lens-related dry eye, reports a study published in Cornea.1 Dry eye syndrome has previously been linked to O3FA deficiency.
In a randomized, double-blind, multicenter trial, researchers from India administered either O3FA or a corn oil placebo to 496 contact lens wearers in two groups twice daily for six months. Patients answered a questionnaire covering dry eye symptoms and lens wear comfort at baseline, three months and six months, and also underwent tear break-up time (TBUT), Schirmer testing and conjunctival impression cytology.
Researchers observed a significant improvement in symptom score of the O3FA group (4.7) compared with the placebo group (0.5). Lens comfort levels also reportedly improved. Interestingly, while there was a significant increase in TBUT (3.3) and Nelson grade (0.7) in the O3FA group as compared with 0.3 and 0.1, respectively, in the placebo group the magnitude of Schirmer increase (2.0) was relatively small.
1. Rajalakshmy AR, et al. Patients with dry eye without hepatitis C virus infection possess the viral RNA in their tears. Cornea. 2015;34(1):28-31.
• Corneal crosslinking
(CXL) does not affect scleral lens tolerance in patients with progressive keratoconus,
according to a small prospective study in the March 2015 Optometry and Vision Science
However, lens fit should be reevaluated after CXL, as some fitting parameters can change.
Researchers evaluated scleral lens-corrected distance visual acuity (CDVA), lens specifications, fit and wear time in 18 scleral lens patients before and one year after CXL. Researchers found no significant change in CDVA before and after CXL was performed; however, 11 of the 18 eyes experienced a spherical scleral lens power change. Individual scleral lens fitting parameters (e.g., radius, toricity, sagittal depth, diameter) changed in 17% to 50% of cases. Wearing time and subjective tolerance remained fairly stable across the board.
1. Visser ES, Soeters N, Tahzib NG. Scleral lens tolerance after corneal cross-linking for keratoconus. Optometry and Vision Science 2015;92(3):318-23.