View clinical trials related to Refractive Errors.
Filter by:Corrective eye surgeries, such as Lasik, are widely used to correct focusing problems such as myopia, or nearsightedness. Often these patients develop other conditions like myopic maculopathy or glaucoma which require monitoring with optical coherence tomography (OCT). Since OCT is a light-based test and changes the refractive status of the eye (in the cornea or the lens), it can potentially affect the results of the OCT measurements but has not been sufficiently studied. This pilot study aims at studying the potential change in OCT parameters in the eye after undergoing such surgery.
This is a 12-month longitudinal randomized controlled trial aiming to evaluate the effect of colour temperature of reading lamp on refractive error development.
The objective of this intervention study was to understand the visual health status of nearly one million children and adolescents in ten provinces in China, and then to conduct intervention and evaluate the effect of intervention measures with the development of myopia as the outcome indicator. The study will be conducted in the form of a stepped intervention and will answer the following questions. Current China children and adolescent's vision health, including the different degrees of myopia prevalence, and farsightedness reserve status. To evaluate the implementation and effect of eight appropriate technologies and six interventions developed in this study, to reduce the incidence of myopia among children and adolescents in China, to achieve the purpose of nationwide application. In the early stage of this study, a baseline survey will be conducted on participants. In the middle stage, participants will be required to adjust the seat height regularly and increase the time for outdoor activities, etc. In the later stage, intervention measures will be evaluated based on the overall research situation to consider national promotion.
This study will be a 2-phase, prospective, multicenter, open-label, non-comparative, non-randomized clinical investigation to confirm the safety and effectiveness of the ELITA system.
This prospective non-comparative interventional study aims to analyse the pre-operative factors affecting the range of optimal ICL vaulting. the main question is what is the correlation between age, gender, spherical equivalent, white to white, anterior chamber volume and depth and postoperative vault? participants will do preoperative investigations ( specular microscopy, pentacam and biometry ) then refractive surgery (ICL implantation) followed by follow-up visits to assess the post-operative ICL vault and visual outcome.
There was a prospective cohort observational study. Forty hyperopic children, 40 myopic children and 120 emmetropia children were randomly selected from grade 1 to grade 3, and were followed up every six months for 3 years. All patients received cycloplegic refraction examination, ocular biological test, binocular visual function test and a questionnaire related to daily eye habits. A multi-level and multi-dimensional data analysis model was constructed to explore the possible factors affecting the occurrence and development of myopia in children.
The purpose of this clinical trial is to evaluate the effect of repeated low-level red-light (RLRL) therapy on the retinal function and structure among myopic teenagers.
The purpose of this prospective multicenter clinical study is to evaluate the visual and refractive outcomes and safety outcomes following bilateral implantation of trifocal and/or trifocal toric 1stQ AddOn (Medicontur) intraocular lenses (IOLs) to correct residual refractive errors, astigmatism, and presbyopia in previously pseudophakic eyes.
Results of retinal detachment surgery may be affected in cases with history of previous intraocular surgery.
The investigators aim to conduct a mixed-method study in which a randomised controlled trial (RCT) and a descriptive qualitative study will be conducted. The RCT aims to determine whether free near and distance glasses provided to residents in Hyderabad, India, aged ≥ 60 years, with under- or un- corrected refractive error and normal baseline hearing and cognition (HMSE > 18), can improve quality of life, reduce falls, reduce depression, improve social interaction and physical activity cost-effectively over 36 months. The primary qualitative research aim is to a) contextualize the RCT with information on the milieu and culture in which the trial will be conducted; b) provide data on the lived experiences of older adults with reduced vision in the study area, and c) conduct a process evaluation of the trial. The primary outcome measure is the three-year change in cognition measured by LASI- DAD (Longitudinal Aging Study in India(LASI)- Diagnostic Assessment of Dementia(DAD) global cognitive score. Secondary Outcome Measures: Domain-specific cognitive function (orientation, executive function, language/fluency, memory), quality of life (WHOQOL BREF), self-reported visual functioning (INDVFQ), falls, mobility, depression (PHQ9), glasses compliance, cost-effectiveness (total intervention cost per additional quality-adjusted life years(QALY) gained in the intervention group), social interaction/isolation (Social Networking Index, SNI), self-reported physical activity (GPAQ). An additional secondary outcome will be LASI-DAD global cognitive score analysed by excluding any tests determined pre-hoc to depend on visual acuity.