View clinical trials related to Refractive Errors.
Filter by:The purpose of this study is to evaluate worn AIR OPTIX® plus HYDRAGLYDE® (AOHG) lenses cleaned and disinfected with HYDRAGLYDE® containing lens solutions compared to each of the control habitual silicone hydrogel (SiHy) lenses cleaned and disinfected with habitual multi-purpose solution (MPS) for cholesterol uptake.
The purpose of this study is to evaluate the initial safety of the UV-FS laser in humans.
The purpose of this study is to evaluate the impact of back surface molded marks (MM) applied to delefilcon A contact lenses as measured by the incidence of ocular discomfort device-related adverse events with DAILIES TOTAL1® Multifocal contact lenses with molded marks (DT1 MF MM) and current DAILIES TOTAL1® Multifocal contact lenses (DT1 MF).
Refractive surgery includes interventions to correct refractive errors, using a medical device such as a laser or an implant (intraocular lenses) or surgical instruments. The study distinguishes corneal interventions, carried on the surface of the eye, and intraocular interventions, performed on the lens or in the anterior or posterior chamber of the eye. The number of procedures in refractive surgery is growing significantly. They seem to offer satisfactory visual results but a number of issues remains unresolved. In order to get emmetropia, refractive surgery corrects optical defects by decreasing aberrations of lower orders (ie spherical refractive error and astigmatism). This increases high-order aberrations (the most common is a bright halo on the edge of the image). The cutting of the flap to the surface of the cornea in the case of LASIK increases high-order aberrations, which have the effect of reducing post-surgical visual performance (ie visual acuity and contrast sensitivity) and can't be corrected by glasses, while the adaptation of contact lenses on a post-operative cornea is more complex. It is therefore necessary to limit these post-surgical aberrations and to identify their possible sources. Indeed, some authors have provided insight into the effects of some high-order aberrations, but the influence of several factors characterizing the preoperative eye on refractive surgery are still unknown, such as pupillary diameter, depth of the anterior chamber, Intra Ocular Pressure or astigmatism.
Subjects will wear 2 of 2 study contact lenses for a wearing time of approximately three to four hours at each of the visits in order to take measurements on binocular functional visual performance.
The purpose of this study is to evaluate DAILIES TOTAL1® Multifocal (DTl MF) contact lenses in current multifocal contact lens wearers with symptoms of end of day discomfort compared to their habitual multifocal contact lens correction.
The purpose of this study is to carry out an international multicenter trial to get more convincing and valuable results of the SMILE surgery and compare the outcomes between the SMILE surgery and the FS-LASIK (femtosecond laser assisted-laser in situ keratomileusis) surgery. The investigators hope to investigate the differences between the SMILE and the FS-LASIK surgery comprehensively, including the comparison of visual acuity, refraction, the correction of cylindrical diopter, the high order aberrations, the corneal biomechanics, the corneal ectasia, the characteristics of the changes of central corneal thickness and the complications. To meet the demands of a multi center trial, all the examination equipments should be same in each center, and this will limit the variations within a study
Study to evaluate the safety and efficacy of HI-BRITE large diameter rigid gas permeable contact lens (hexafocon b) test when worn on a daily wear basis in the correction of myopia/hyperopia/astigmatism/presbyopia/ and irregular cornea.
The purpose of this study is to evaluate the safety and efficacy of FID 120947A in soft contact lens wearers of Japanese ethnicity.
The purpose of this study is to compare the lens fit characteristics, specifically lens centration, of ACUVUE® OASYS® 1-DAY (AO1D) contact lenses and DAILIES TOTAL1® (DT1) contact lenses.