Effect of long-term wearing rigid gas permeable contact lenses on the stability of tear film / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

· AIM:To investigate the effect of long-term wearing rigid gas permeable (RGP) contact lenses on the stability of tear film,and to observe its safety.· METHODS:Totally 60 myopia patients (120 eyes) wearing RGP in our hospital from October 2014 to January 2016 and 30 low myopia patients (60 eyes) without a history of wearing RGP were selected.There were 26 patients (52 eyes) wearing RGP at daytime were included into daytime wearing group;34 patients (68 eyes) only wearing RGP at night were set as the night wearing group.And patients without wearing RGP were set as control group.Schirmer Ⅰ test (S Ⅰ t),tear film fern experiments,and break-up time (BUT) of tear film were performed before wearing RGP,wearing for 1 mo,wearing for 6mo,wearing for 1a,wearing for 2a,respectively.· RESULTS:After wearing RGP,the BUT and S Ⅰ t of daytime wearing group and night wearing group significantly decreased,and were significantly lower than those of the control group at the time points,the difference was statistically significant (P＜ 0.05).After wearing for 6mo,1a and 2a,the BUT and S Ⅰ t of daytime wearing group was significantly lower than that of the night wearing group,the statistic found significant difference (P＜0.05).The three groups had no statistically significant differences in tear fern classification experiment before wearing RGP and wearing for 1 and 6mo (P＞0.05).The number of the eyes ≥ Ⅲ in daytime wearing group and night wearing group was significantly higher than that of the control group after wearing for 1 and 2a,the difference was statistically significant (P＜ 0.05),but the difference between daytime wearing group and night wearing group found no significant difference (P＞0.05).· CONCLUSION:Wearing RGP can result in reducing tear secretion and decreasing the stability of tear film.