Dr.Sudha Seetharam, Dr.Vijay Shetty, Dr.Suhas Haldipurkar, Prafulla Kuthe
Fitting of rigid gas permeable contact lens in keratoconus requires meticulous selection of base curve and lens diameter in order to achieve an optimum fit ensuring best possible visual acuity and patient comfort. Pentacam (Oculyzer) can serve as a valuable tool in this regard. Base curve of the trial lens is selected with the help of simulated keratometry (Sim-K) values on Oculyzer. Diameter of the trial lens depends on the type and position of the cone. After insertion of the trial lens, fluorescein staining is done. Central fit, peripheral fit, overall diameter, location and movement of the trial lens are assessed on the slit lamp under cobalt-blue filter. Parameters of the lens are refined depending on the fit achieved with the trial lens. Over-refraction is done after an optimum fit is achieved.