View clinical trials related to Refractive Errors.
Filter by:This study is exploratory and examines whether the refraction results obtained from a novel optical device yields results similar to the ophthalmic refraction measurements obtained from an autorefractor in children.
The purpose of this study is to evaluate the overall performance of PRECISION1™ contact lenses when compared to INFUSE™ contact lenses.
The purpose of this study is to compare the clinical performance of PRECISION1™ for Astigmatism (P1fA) contact lenses with 1-DAY ACUVUE MOIST® for ASTIGMATISM (AMfA) contact lenses.
The purpose of this study is to compare the clinical performance of PRECISION1™ contact lenses to Clariti® 1 day contact lenses.
The investigator want to determine the refractive status of 80 children with disabilities and of 81 healthy children from a witness group. The vitamin D level of the children will be dosed for making different correlations with visual acuity status.
Measuring parameters of anterior segment of the eye accurately is important for diagnosing variety of diseases and for cataract surgeries, glaucoma, refractive surgeries and post-operative follow-up. One of the anterior segment parameters is the anterior chamber depth. The anterior chamber depth (ACD) measurement provides valuable information in different fields in ophthalmology. Firstly, it is important for the new theoretical biometric formulas used to calculate the power of intraocular lenses (IOLs) .Secondly, phakic IOL implantation requires precise ACD measurement for both surgical planning and IOL power calculation. Thirdly, the ACD is also implicated as a screening risk factor for glaucoma. Additionally, precise ACD measurement is thought to be important to the accurate determination of the optic zone ablation diameter for keratorefractive surgery, as well as for the analysis of postoperative ACD changes. Different technologies are used in measurement of the anterior chamber depth Such as pentacam and iol maste
LASIK (laser-assisted in situ keratomileusis) is a type of refractive surgery for correction of myopia, hyperopia and astigmatism. Yet approximately 30% of operated patients have symptoms like glare, halos, dry eyes and especially residual hypermetrop refractive errors. Residual hypermetrop refractive errors are difficult to treat surgically, the current treatment is Refractive Lens Implantation - risks are similar to those of cataract surgery (endophthalmitis, loss of accommodation, etc.)
The purpose of this study is to evaluate corneal staining observed after 2 hours of wear with an investigational contact lens against both PureVision contact lenses pre-cycled with Biotrue and Biofinity contact lenses pre-cycled with RepleniSH.
To evaluate the refractive outcomes of cataract surgery in PEX syndrome and determine which of the commonly used IOL formulas (SRK/T, Barrett Universal II and Hill-RBF) is the best in predicting postoperative refractive outcomes in PEX.
Primary objective of this study is the development and validation of a web-based application for the examination of the distance visual acuity of normal- and low-vision patients.