ABSTRACT

To evaluate the effects of silicone hydrogel contact lenses (SHCL) on central corneal thickness (CCT), corneal endothelial cell morphology, and tear functions.

Fifty-five eyes of 28 SHCL wearers (Group 1) and 52 eyes of 26 healthy subjects (Group 2) were included in this study’. According to their contact lens wearing time, the contact lens wearing subjects were divided into 2 groups: Group 1a - wearing time less than 1 year and Group 1b - wearing time more than 1 year. CCT, epithelial thickness, corneal endothelial cell morphology, ocular surface disease index score (OSDI), and tear break-up time (TBUT) were evaluated.

In Group 1 and Group 2, the mean CCT was 561.85±39.98 μm and 537.25±27.12 μm, respectively (p: 0.001).The epithelial thickness was 50.38±5.41 μm and 55.64±5.32 μm, respectively (p: 0.001). In Group 1a and Group1 b, the mean CCT was 573.39±33.86 μm and 546.96±42.98 μm (p: 0.014) and the epithelial thickness was 49.51±4.78 μm and 51.50±6.04 μm (p>0.05), respectively. In Group 1, the percentage of endothelial cells larger than 700μ was low, while the percentage of endothelial cells between 200 and 400μ was high (p<0,05).

With SHCL wear, the corneal morphology is more affected in the short-term period. During long-term contact lens wear, the cornea enters an adaptation period and shows near-normal morphology. Tear functions are not affected by short- or long-term SHCL wear. (Turk J Ophthalmol 2012; 42: 91-6)