View clinical trials related to Refractive Errors.
Filter by:In a randomized controlled trial, we will establish whether early glasses for high refractive error at age one reduce the development of amblyopia between age one and four. As a secondary outcome early literacy will be compared in groups with and without glasses.
Primary objective of our study is the development and validation of an application for smart-TVs for the self-examination of the distant visual acuity of patients diagnosed with macular edema.
The purpose of this multicenter randomized clinical trial is to evaluate the adjunctive effect of repeated low-level red-light therapy (RLRL) and orthokeratology (ortho-k) on myopia control in ortho-k non-responders who have undergone ortho-k treatment but were still experiencing fast myopia progression.
The purpose of this study is to compare the results of vision tests that are algorithmically derived and delivered through a virtual reality headset with those delivered through the existing technology standards (eg. Humphrey for field tests). Tests that the researchers will be conducting include vision field perimetry, Amsler, acuity chart, contrast- sensitivity and currently used office tests.
We aimed o compare the refractive changes associated with pars plana vitrectomy with or without intraocular gas tamponade in pseudophakic eyes. This retrospective study included pseudophakic patients with Nd:YAG laser posterior capsulotomy who underwent 23G PPV between February 2015 and March 2019. Group 1 consisted of patients with regmatogenous RD who underwent PPV and 12% perflouropropane (C3F8) gas tamponade whereas Group 2 consisted of patients who underwent PPV for epiretinal membrane or vitreous hemorrhage (VH). No tamponade was used in Group 2. Minimum follow-up was 12 months.
Successful treatment of residual refraction 6 months after IOL Implantation with Relex-Smile.
The primary objective of this study is to evaluate the overall clinical performance of an investigational silicone hydrogel contact lens over 7 days of daily wear.
The two main objectives of this study are to demonstrate safety and effectiveness of implanting the PanOptix Trifocal IOL in patients who have had previous myopic Lasik. The primary objectives to demonstrate clinical safety will be the quality of vision questionnaire (QUVID) which will demonstrate the patient's perception of halos, glares, and starbursts before and after the implantation of the trifocal IOL. The primary objective to demonstrate clinical effectiveness will be done by measuring visual outcomes at distance, intermediate, and near. In addition, the patients will also fill out the spectacle independence questionnaire (IOLSAT Questionnaire) to determine their level of glasses independence postoperatively. In addition, at the conclusion of the study the patient will also fill out a patient satisfaction survey.
This is a prospective, comparative, randomized, controlled, single-blind, single-surgeon, single-center PMCF clinical study whereby participants undergoing refractive surgery for correction of ametropia will receive a transepithelial PRK (tPRK) and conventional PRK treatment in the contralateral eye. To avoid bias in the clinical outcomes, the two PRK treatment options are randomized to the eyes of the patients based on ocular dominance. In addition, a 1:1 randomization is applied within the tPRK group to eyes with and without end-treatment laser polishing. Both procedures, standard PRK and tPRK, are performed in a one-step procedure. The main difference between the procedures is, that in conventional PRK, the epithelium will be removed using alcohol, whereas in tPRK procedures, the epithelium will be removed by laser ablation.
This study is exploratory and examines whether the best-corrected visual acuities (BCVA's) from trial frames created with the refraction results obtained from a novel handheld optical device yields results similar to the ophthalmic refraction obtained from an autorefractor in healthy volunteers age stratum of 18 through 65 years.