View clinical trials related to Refractive Errors.
Filter by:The study will compare the short-term clinical performance and wearer and practitioner acceptability in a pilot study of a new-to-market spherical silicone hydrogel daily disposable soft contact lens (SiHyDD) to three (3) benchmark soft daily disposable lenses (DD) and, subsequently, of a new-to-market hydrogel spherical daily disposable (HydDD) soft contact lens to three (3) other hydrogel daily disposable lenses. . The primary outcome variables for this study are subjective comfort and lens preference.
The purpose of this study was to compare the clinical performance of the new DAILIES® AquaComfort PLUS® FreshTech (DACP FreshTech) contact lenses to an already marketed daily disposable contact lens, DAILIES® AquaComfort PLUS® (DACP).
To assess the improvement in refractive error and the corneal endothelial safety with a customized corneal crosslinking treatment regimen for low grade myopia. The study compares two treatment protocols, a 4.0-mm central ring-shaped zone with a 3.5-mm central ring-shaped zone in high oxygen environment without corneal epithelial debridement.
Some programs do the screening, refraction testing and provision of spectacles to children entirely in the school setting ("School Model"). One strength of such programs is that most children at school who need spectacles get them. However, sustainability is poor, because spectacles cannot be sold in many schools and there may be too few refractionists to cover all schools in most countries. Other programs provide vision screening at schools but refer children who fail vision screening to nearby facilities for refraction and distribution/sale of spectacles ("Referral Model"). This model's strengths include a lower demand for refractionists and opportunities for the spectacles to be sold. However, a disadvantage is that most of the referred children do not attend the specialist facility. One way to improve this might be to enhance the Referral Model and a recent USAID review by Priya Reddy and Ken Bassett showed that involving teachers in vision screening and family counseling significantly increases children's use of spectacles. Therefore, at 141 schools in India, involving over 42,300 children (assuming a minimum of 300 children/school), the investigators will study an "Improved Referral Model," with strong teacher involvement, to investigate the potential benefits of combining the lower costs of the "Referral Models" with the high uptake of the "School Model". The investigators will also assess the effects of allowing parents to purchase enhanced spectacles, rather than having their child use free spectacles. Children will be randomized by the school to the "School Model," "(Improved) Referral Model" or the "(Improved) Referral Model + Cost Recovery (sale of "upgrade spectacles" alongside offering free spectacles. The main study outcome will be program cost-effectiveness, defined as the program cost per child identified with correctable refractive error, who receives spectacles, and wears them at an un-announced visit between 8 to 12 weeks after distribution. Profit on spectacles sold in the "Referral + Cost Recovery" group will be subtracted from the program costs in this study group. The groups will be compared, with and without adjustment for baseline characteristics.
The objective of this clinical investigation is to collect valid scientific safety and effectiveness data on the Acuity 200 (fluoroxyfocon A) Rigid Gas Permeable Contact Lens, manufactured from a newly developed rigid gas permeable material that is highly permeable to oxygen. The clinical performance data reported from this study is intended to be submitted to the U.S. Food and Drug Administration Center for Devices and Radiological Health (CDRH) in support of a 510(k) premarket notification.
The Lentechs Apioc-S and Apioc-A contact lenses are made in an FDA-approved contact lens material indicated for single-vision and astigmatism. The novel lens design has a lenticular portion which is thicker than the optical portion of the lens. When applied to the eye, it is oriented in a superior position. Unlike contact lenses currently on the market, this innovative design improves lens stability by preventing lens rotation, and may improve tear flow behind the lens.
The purpose of this study is to evaluate end of day (EOD) visual acuity (VA) at distance when wearing Precision1™ contact lenses compared to Acuvue® Moist contact lenses.
Single-center, open-label, prospective study in healthy volunteers desiring refraction for correction of visual acuity to compare a handheld device supported by a mobile application with the phoropter and autorefractor.
The purpose of this clinical study is to demonstrate the safety and performance of an investigational soft contact lens compared to a commercially available soft contact lens when worn in a daily wear modality.
The purpose of this study was to evaluate visual acuity at distance when wearing DDT2 contact lenses compared to Clariti contact lenses.