View clinical trials related to Visual Acuity.
Filter by:This is a randomized, double-masked dispensing study where subjects will randomized into one of two lens sequences to wear each of two contact lens types for a 4-week period with each lens type.
This is a multi-site, 5-visit, double-masked, dispensing study comparing an investigational contact lens with currently-marketed contact lenses. The objective of the study is to evaluate the comfort of the lenses when worn for 30 (-2/+6) days on daily wear modality.
This is a 4-week, randomized, double-masked study where subjects will wear bilaterally test and control lenses in random succession. The objective is to evaluate materials from different suppliers.
This is a single-visit prospective study to establish a real world Marketed Contact Lens 'Through Focus Curve' (TFC) measurement by comparing the consistency of vision between myopes and hyperopes. 33 subjects will be enrolled (at least 15 myopes and 15 hyperopes), who are 40 years of age or older, for a 1-visit, 4-hour study for measurements to be taken.
The purpose of this study is to evaluate the safety and performance profile of the suprachoroidal surgical approach and the Delivery System.
This is a single-site, 8-visit, double-masked, cross-over study involving three marketed products as study lenses. Participants will be randomly assigned each lens type, which will be worn for approximately two weeks (12 +/- 2 days) each. Participants will undergo a minimum washout period of 3 days before entering the study and undergo a minimum 7 day washout period between dispensing each lens type.
Approximately 120 subjects will be comparing two soft contact lenses for one week each.
The WHO, states that age related cataracts account for 51 percent of worldwide blindness and affect about 20 million people. Surgery with intraocular lens (IOL) implantation is the first line treatment for cataracts, thus there is an on going effort to improve IOL design and performance. It is planned to compare three different IOL designs in a psychophysical test setting. Most IOL testing is done in 2D scenarios such as Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity or contrast sensitivity testing. The use of 3D scenario would allow testing a more real-life situation. As various downsides of different IOL designs have been reported, testing of IOLs before surgical implantation is a promising approach to maximise patient satisfaction. Known deficiencies include amongst others reduced contrast sensitivity or light intensity. To test three different IOL designs, it is planned to have 2D healthy young subjects look through a stable, table mounted spectacle frame, in which the different IOLs can be inserted. This allows for subjective testing of IOL's in a 2D and 3D scenario.
The primary objective of this study is to evaluate the clinical performance of two marketed silicone hydrogel contact lenses in an Indian population in the following areas: physiological characteristics, comfort characteristics and vision characteristics.
In vitro studies show that some hydrogel materials uptake more lysozyme than other hydrogel materials and that this protein remains largely active and promotes reduced cytokine response in an in vitro culture of human corneal epithelial cells. This study investigates whether these data transfer to the in vivo situation.