부산대학교 도서관

PURPOSE: To establish the effect of lipid supplements on the tear lipid layer and their influence on lens wear comfort in habitual lens wearers. METHODS: Forty habitual soft contact lens wearers were recruited to a double-masked, randomized crossover trial. An emulsion drop containing phosphatidylglycerine (Systane Balance; Alcon) and a saline drop as a placebo or a liposomal spray containing phosphatidylcholine (Tears again; BioRevive) and a saline spray as a placebo were used three times a day for 2 weeks with 48 hours washout between each intervention. Ocular comfort, lipid layer grade, and stability of the tear film using a Tearscope and tear evaporation rate using a modified VapoMeter were assessed after 6 hours of lens wear with lenses in situ. RESULTS: Neither of the lipid supplements improved lens wear comfort compared to baseline. The noninvasive surface drying time significantly reduced with the placebo spray at day 1 (P = .002) and day 14 (P = .01) whereas the lipid spray had no effect. With the lipid drop and placebo, noninvasive surface drying time was unchanged compared to baseline (P > .05) on day 1, but by day 14, noninvasive surface drying time was reduced with the lipid drop (P = .02) and placebo (P < .001). Symptomatic wearers showed shorter noninvasive surface drying time compared to asymptomatic wearers with the spray treatment on both days (P = .03) but not with the lipid drop (P = .64). The placebo drop significantly changed the lipid layer distribution (P = .03) with a higher percentage of thinner patterns compared to the baseline distribution at day 14. A weak but significant correlation was shown between ocular comfort and noninvasive surface drying time (r = −0.21, P = .003) and tear evaporation rate (r = 0.19, P = .008). Ocular comfort was not associated with lipid layer patterns (r = 0.13, P = .06). CONCLUSIONS: Ocular comfort during contact lens wear improved with increased tear film stability and a reduced tear evaporation rate. However, the lipid supplements did not improve ocular comfort from baseline.