Comparison of ocular aberrations in three types of rigid gas permeable lenses in keratoconus patients

Abstract

Purpose: To determine the effect of different types of Rigid Gas Permeable (RGP) contact lenses on ocular aberrations in patients with keratoconus. Methods: Eighteen eyes of young patients with mild to moderate keratoconus were selected. General ocular examinations such as refraction, visual acuity, and ocular aberrations were performed. Three types of RGP contact lenses, i.e., Boston, Senso Select and Wohlk, were fitted using the cross over method. Repeated measures analysis of variance and Mauchly's test of sphericity were used to compare the average of residual high order aberrations and visual acuity after fitting each type of lens. Results: Vertical coma was -0.271 ± 0.37 µm before fitting and decreased to 0.081 ± 0.08 µm with Boston, 0.098 ± 0.08 µm with Senso Select and 0.124 ± 0.08 µm with Wohlk contact lens (P-value < 0.0001). The mean RMS (root mean square) for high order aberrations decreased from 0.526 ± 0.43 µm before fitting to 0.256 ± 0.09 µm with Boston, 0.263 ± 0.12 µm with Senso Select, and 0.304 ± 0.10 µm with Wohlk contact lens (P-value= 0.001). The mean RMS for low order aberrations decreased from 1.480 ± 0.78 µm before fitting to 0.703 ± 0.43 µm with Boston, 0.802 ± 0.39 µm with Senso Select, and 0.760 ± 0.45µm with Wohlk (P-value < 0.0001). Conclusion: Despite achieving optimal fit and good visual acuity with these different RGP lenses, in keratoconus patients, their performance is different in reducing ocular aberrations.

Assessment of large‐diameter and small‐diameter SoftK specialty contact lenses for early‐stage keratoconus

“…was greater than that observed with soft lenses in this study. However, the improvement in the total RMS was greater with the soft lenses used here, compared with Torkman et al 30 …”

“…Further, in an investigation that examined the improvement in HOA with three types of RGP lenses in 18 eyes of keratoconic participants using a Hartmann-Shack device, mean improvements in vertical coma of 0.35, 0.37 and 0.39 μ were reported. 30 The improvement in coma with RGP lenses reported by Torkman et al 30 was greater than that observed with soft lenses in this study. However, the improvement in the total RMS was greater with the soft lenses used here, compared with Torkman et al 30 Differences between these findings may be attributed to use of varying instruments and lens designs.…”

“…30 The improvement in coma with RGP lenses reported by Torkman et al 30 was greater than that observed with soft lenses in this study. However, the improvement in the total RMS was greater with the soft lenses used here, compared with Torkman et al 30 Differences between these findings may be attributed to use of varying instruments and lens designs. Despite these differences, they demonstrate that the LD-SoftK and SD-SoftK lenses provide improvements that are similar to those obtained with RGP lenses for patients presenting with grades I or II KC (Amsler-Krumeich classification).…”

“…Further, in an investigation that examined the improvement in HOA with three types of RGP lenses in 18 eyes of keratoconic participants using a Hartmann–Shack device, mean improvements in vertical coma of 0.35, 0.37 and 0.39 μ were reported 30 . The improvement in coma with RGP lenses reported by Torkman et al 30 .…”