[ effect of rigid gas permeable contact lens fitting in corneal curvature, central thickness and volume]

ABSTRACT

Evaluation of the corneal curvature, central thickness and volume three months after fitting the Rigid Gas Permeable [RGP] contact lens in keratoconic eyes. Corneal topography maps of 25 keratoconic eyes with a negative history of using the RGP lens were evaluated by Oculus Pentacam. Corneal curvature in both surfaces of the cornea, central corneal thickness and corneal volume were evaluated before and three months after fitting the aspheric RGP lens. Three months after using the contact lens, decrease in central corneal thickness [-3.43 micro m, P=0.127], decrease in flattest anterior corneal surface power [-0.43D, P=0.339], decrease in anterior corneal steep power [-1.54D, P=0.358], decrease in posterior corneal flat power [-0.1D, P=0.121], an increase in posterior corneal steep power [0.02D, P=0.710] and an increase in corneal volume [0.27 mm[3] P=0.331] were not statistically significant. Lack of significant changes in corneal topographical parameters three months after using the RGP lens may indicate the non progressive nature of keratoconus in this period. Further studies with longer follow-up periods are suggested to obtain more accurate results: