RÉSUMÉ
AIM: To study the effects of Sodium Hyaluronate (HA) and Bion Tears on corneal thickness in adult myopic patients.METHODS: A total of 38 cases (76 eyes) were involved in this study. Three consecutive corneal measurements (the thinnest point of the cornea,THN) were evaluated before and half an hour after the instillation of one drop of HA in one eye and Bion Tears in the other at random with the Orbscan Corneal Topography System II (Orbscan,Inc,Salt Lake City,UT,USA,Version 3.00E).RESULTS: There were no significant between-group differences in baseline variable (t=0.264). Thirty minutes after the instillation of HA and Bion tears,THN were significantly increased by 5.57±7.00μm (t=4.906,P<0.01) and 7.89±7.64μm (t=6.369,P<0.01) respectively. However,there were no between-group differences in THN changes(t=1.381,P>0.05).Increase in the corneal thickness were found in 32 eyes (84%) and 33 eyes (87%) for the HA and Bion tears group,respectively.CONCLUSION: Artificial tears including HA and Bion Tears can significantly increase the corneal thickness in a short period of time. Corneal thickness can be used as one of the objective indices for evaluating the quality and therapeutic role of artificial tears.
RÉSUMÉ
PURPOSE: To evaluate central corneal thickness and pachymetry maps in myopic eyes. METHODS: 104 eyes of 52 myopic patients were investigated using the Orbscan (Orbtek, Inc., USA). The pachymetry maps were designated as round, oval, decentred round, and decentred oval. Corneal thickness was evaluated at the central, eight-paracentral, and the thinnest sites on each of the corneas. We studied difference of corneal thickness under sex and myopic degree. And got the symmetry of the cornea under location of the thinnest sites. RESULTS: Superior cornea had the greatest average thickness (605.5+/-35.3 mu m). Average central corneal thickness (+/-SD) was 552.2 (+/-34.9) mu m. All corneas had the thinnest sites on 0.86 mm from the visual axis and most of all inferotemporal area (76.0%). There was no significant difference of corneal thickness in sex and myopic degree. Average thickness of the thinnest sites was 544.2 (+/-35.6) mu m and significantly thinner than center. 61.5% of the persons had symmetrically located thinnest corneal sites and most of all (57.7%) had temporal side symmetry. In the pachymetry maps, oval pattern was 47.1% of 104 eyes, andround, decentred oval, decentred round were observed in 43.3%, 5.8%, and 3.8% of eyes, respectively. CONCLUSIONS: Of all myopic eyes evaluated in this study, the thinnest sites were on average 0.86 mm from the visual axis. And oval type was the most common pachymetry map pattern.