A Comparison of Ocular Health and Visual Quality With Corneal and Scleral Rigid Gas Permeable Lenses in Keratoconus Patients

What this Trial Is About

Researchers are evaluating the effects of two types of rigid gas permeable lenses—corneal (CRGPL) and scleral (SRGPL)—on eye health and visual quality in patients with keratoconus, a condition that causes thinning and irregular shaping of the cornea leading to vision problems. This crossover clinical trial aims to compare subjective experiences like comfort and visual function, as well as objective measures including visual acuity, contrast sensitivity, and higher-order aberrations. The study also examines how each lens type impacts the health of the eye's surface tissues and tear film. Participants will be randomly assigned to wear either the corneal RGP lens (Rose K2) or the scleral RGP lens (Onefit MED) for six weeks, followed by a one-week washout period, then switch to the other lens type for another six weeks. The corneal lens fits within the corneal diameter, while the scleral lens is larger and rests on the conjunctival tissue. Both lenses are designed with flexible parameters to suit individual needs. The study involves detailed eye examinations and measurements during each phase. During the study, participants will undergo various assessments including best corrected visual acuity measured by ETDRS charts, contrast sensitivity, subjective questionnaires on visual function and comfort, and detailed imaging and grading of the cornea, conjunctiva, sclera, and tear film. Higher order aberrations will be measured with specialized aberrometry. Safety and ocular health will be monitored throughout the 13-week study period, including before, during, and after each lens wear phase. Participants will be instructed on proper lens use and care, performing lens wear at home with clinical support.

Effect of Corneal and Scleral RGP Lenses on Ocular Health and Visual Quality in Keratoconus