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)

· 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.

Observation of the curative effect of rigid gas permeable contact lens in the treatment of adult high and special type ametropia / 国际眼科杂志(Guoji Yanke Zazhi)

?AlM:To explore the use of rigid gas permeable ( RGP ) contact lens, and its clinical effect and safety in the treatment of adult high and special type ametropia. ? METHODS: Totally 110 cases ( 185 eyes ) of Ophthalmology Center fitting of RGP from January 2010 to December 2012 were retrospective analyzed. According to the refractive error types, patients were divided into high myopia astigmatism group( 49 cases, 92 eyes), 36 cases (64 eyes) of keratoconus group, special ametropia group (25 cases, 29 eyes). Corrected visual acuity differences, adverse reactions of different temporal acuity and conventional frame in the three group were observed after wearing RGP. ?RESULTS:After wearred RGP, corrected visual acuity of high myopic astigmatism group was 4. 94 ± 0. 16, keratoconus group was 4. 98±0. 15, and special ametropia group was 4. 87±0. 19; they were significantly better than wearing frame mirror 4. 86±0. 23, 4. 79±0. 22, 4. 61±0. 27 and the differences were statistically significant (P ?CONCLUSlON: Wearring RGP can correct adult high and special type ametropia than ordinary frame glasses, which avoid the occurence of dry eye, foreign body sensation, and easy fatigue. lt is worthy of clinical application.

Sustainability of Orthokeratology as Demonstrated by Corneal Topography

PURPOSE: To determine the sustaining effects of orthokeratology. METHODS: This study enrolled 58 eyes with moderate myopia. LK-DM lenses (Lucid Korea Dream Lens(TM)) were fitted daily for at least eight hours on an overnight regimen. The effects of orthokeratology and it's sustainability throughout the day were recorded twice; immediately after removal in the morning and eight hours later. Sustainability was measured by comparing the changes from morning to afternoon for best uncorrected visual acuity, apical corneal power, keratometric values, spherical equivalent and induced astigmatism. RESULTS: UCVA demonstrated improved values at all follow up periods. Fluctuations during the day stabilized after 4 weeks of lens wear. K values averaged a mean of 42.4 mm at baseline, and reduced to 40.9 mm by week 12. Unaided logMAR visual acuity changed from 0.94+/-0.14 at baseline to -0.11+/-0.17 by week 12. The sustainability of orthokeratology, defined as the difference between morning and afternoon values of unaided logMAR visual acuity, increased from -0.82 on day 1 to -0.11 on week 12. CONCLUSIONS: UCVA and spherical refractive error did not change to a significant degree after 4 weeks. Although statistically insignificant minute fluctuations during the day were observed up to week 12, these fluctuations decreased to a statistically significant level after week 4.

Sustainability of Orthokeratology as Demonstrated by Corneal Topography

PURPOSE: To determine the sustaining effects of orthokeratology. METHODS: This study enrolled 58 eyes with moderate myopia. LK-DM lenses (Lucid Korea Dream Lens(TM)) were fitted daily for at least eight hours on an overnight regimen. The effects of orthokeratology and it's sustainability throughout the day were recorded twice; immediately after removal in the morning and eight hours later. Sustainability was measured by comparing the changes from morning to afternoon for best uncorrected visual acuity, apical corneal power, keratometric values, spherical equivalent and induced astigmatism. RESULTS: UCVA demonstrated improved values at all follow up periods. Fluctuations during the day stabilized after 4 weeks of lens wear. K values averaged a mean of 42.4 mm at baseline, and reduced to 40.9 mm by week 12. Unaided logMAR visual acuity changed from 0.94+/-0.14 at baseline to -0.11+/-0.17 by week 12. The sustainability of orthokeratology, defined as the difference between morning and afternoon values of unaided logMAR visual acuity, increased from -0.82 on day 1 to -0.11 on week 12. CONCLUSIONS: UCVA and spherical refractive error did not change to a significant degree after 4 weeks. Although statistically insignificant minute fluctuations during the day were observed up to week 12, these fluctuations decreased to a statistically significant level after week 4.