Abstract. Objective: To evaluate two solutions, lactated Ringer's (LR) and a balanced salt solution (BSS Plus, Alcon Laboratories, Ft. Worth, TX), compared with normal saline solution (NSS), for ocular irrigation in healthy adult volunteers with and without the Morgan therapeutic lens (MTL). Methods: This was a prospective, double-blind, randomized study of healthy volunteers who were at least 18 years of age. Exclusion criteria included the use of analgesics within four hours of the study. A complete ophthalmologic examination was performed at baseline and a t the completion of the study. Following randomization and prior to any intervention, baseline discomfort scores were obtained by means of a verbally administered, horizontal, lOO-mm, unnumbered analog discomfort scale. Both eyes of each volunteer were irrigated simultaneously for 15 minutes, with additional discomfort scores being recorded every 5 minutes using the same lOO-mm, unnumbered analog discomfort scale. A global evaluation to assess the method of irrigation and the solutions used for irrigation was completed by both the physician blinded to the treatment groups and the volunteers. The volunteers were continuously monitored for any adverse effects resulting from the irrigation solutions or MTL. Results: Sixty-three volunteers were recruited into the study, with 61 entered in the final analysis. Age and gender were balanced within each group. There was no significant difference in discomfort scores between the two groups; however, all discomfort scores decreased over time ( p = 0.008). A lens-solution interaction was identified, with LR being the most tolerated when administered with the MTL. A statistically higher ocular pH difference was seen between the pre-and postirrigation readings for the control eye in volunteers irrigated with MTL ( p = 0.046). Analysis of the global evaluations for each group revealed no difference in the distributions of physician and volunteer scores. No adverse event was reported in either group. Conclusion: There does not appear to be any difference in discomfort scores between the ocular irrigation fluids when used without the MTL. Overall, the use of the MTL appears well tolerated by healthy, adult volunteers. However, there does appear to be a significant lens-solution effect on volunteers' discomfort scores, with LR having significantly lower discomfort scores when used for ocular irrigation with the MTL. The authors conclude that the use of the MTL for ocular irrigation is well tolerated and recommend using LR as the irrigation solution for maximal patient comfort.
