View clinical trials related to Refractive Errors.
Filter by:This study will serve to evaluate and compare the performance of two new lenses to a marketed lens.
The purpose of this study was to demonstrate substantial equivalence of an investigational toric soft contact lens to the commercially available Focus® DAILIES® Toric soft contact lens when worn in a daily wear, daily disposable mode for three months.
The purpose of this study is to examine the short-term protective effect of Ultra-Violet filtering contact lenses on macular pigment ocular density.
The purpose of this study is to examine the long term effect of ultra-violet filtering contact lenses on macular pigment density (MPOD) and accommodative function.
The purpose of this study was to evaluate the subjective and objective performance and the physiological response to AIR OPTIX® COLORS soft contact lenses compared with AIR OPTIX® AQUA contact lenses in participants with normal eyes and prescription needs.
INTRODUCTION. Amblyopia is defined as the loss of visual acuity (VA) in one or both eyes, without any obvious structural or pathological anomalies. Amblyopic eye should be able to regain some VA if treatment is initiated before the age of seven. It is the leading cause of monocular blindness in the 20- to 70-year olds with prevalence 2-5%. Amblyopia is mainly monocular, hence children are general asymptomatic. VA testing is the only reliable method of detecting amblyopia, and the fourth year of life is considered best for vision screening programs. AIM: The purpose of the study is to reduce the preventable vision loss. The main goal of the study is to evidence the problem of amblyopia in Zagreb and to release a model for formal, government directed vision-screening program as a Croatian public health policy. HYPOTHESIS. In Croatia, the prevalence and actual effect of amblyopia and amblyogenic factors, along with treatment efficacy is impossible to quantify, since no population-based studies have been performed regarding this issue. In addition, national screening of preschool children does not exist, while the school-entry screening is prescribed by law. The object of the study is to determine the prevalence of amblyopia in a 4-4.5 year old children of The Town of Zagreb, the efficacy of screening and effectiveness of treatment on reducing amblyopia prevalence. The primary hypothesis is defined: screening of visual acuity monocularly at distance and near in 4-4.5 year old children in Zagreb is effective in detecting amblyopia. PATIENTS AND METHODS: Monocular vision of about 7000 children/ year aged 4-4.5 for whom both parents gave consent is to be tested with Lea chart at near (40cm) and distance (3m) in the kindergartens of The Town of Zagreb. The criterion for referral to complete ophthalmological examination is VA <0.8.
Proof of concept study is to compare the best corrected visual acuity obtained via First-Sight lenses with the clinical "gold standard" of manifest refraction and autorefraction.
By using a new software two consecutive laser treatments have been combined to correct the distance vision and to provide a near vision component in addition to the first treatment. This study will help us to answer 2 questions: 1. How accurately this combined technique corrects distance and near vision 2. Whether the correction is adequate to remove the complete need for supplementary near spectacles
The purpose of this three-month study is to compare the quality of life and ease of fit among children wearing investigational single-vision contact lenses, commercially marketed single-vision contact lenses, and commercially marketed multifocal contact lenses.
The results of this trial will demonstrate that the iDesign System performs as intended and is acceptable in a clinical setting.