View clinical trials related to Myopia.
Filter by:Study in the US intended to evaluate the safety and effectiveness of a Johnson & Johnson Vision Care Inc, (JJVCI) contact lens for use on an extended-wear basis for up to 7 days (6 nights).
The purpose of this study is to determine whether bifocal soft contact lenses are effective in controlling the progression of myopia in children and adolescents that exhibit a tendency to excessively cross their eyes while reading (esophoria or eso fixation disparity). Several studies have demonstrated that bifocal or progressive multifocal spectacles are effective in slowing the progression of myopia in children either with near point esophoria and/or with inadequate focusing at near. A prominent theory for one cause of myopia progression is that poorly focused images on the back of the eye (retina) cause the eye to lengthen, causing an increase in myopia. Bifocal contact lenses may reduce this retinal defocus, reducing the stimulus to eye elongation, and thus may reduce myopia progression.
To examine the effects of rigid gas permeable contact lenses on the progression of myopia (nearsightedness) in children To determine what changes in the eyes cause certain eyes to progress in nearsightedness more slowly
To determine whether radial keratotomy is effective in reducing myopia. To detect complications of the surgery. To discover patient characteristics and surgical factors affecting the results. To determine the long-term safety and efficacy of the procedure.
To evaluate the relative efficacy of orthokeratology, primarily by assessment of changes in central corneal thickness, astigmatism, visual acuity, endothelial cell density, and corneal curvature. To evaluate the relative safety of orthokeratology, primarily by assessment of changes in central corneal thickness, astigmatism, visual acuity, endothelial cell density, induced corneal edema, and epithelial staining. To assess the duration of any orthokeratology treatment effect. To study the mechanisms by which refractive error and visual acuity changes occur, in particular the contribution that comes from changes in corneal curvature and shape. To determine whether there were any predisposing ocular factors that could be used to predict which subjects will experience changes or complications.
To evaluate whether progressive addition lenses (PALs) slow the rate of progression of juvenile-onset myopia (nearsightedness) when compared with single vision lenses, as measured by cycloplegic autorefraction. An additional outcome measure is axial length, as measured by A-scan ultrasonography. To describe the natural history of juvenile-onset myopia in a group of children receiving conventional treatment (single vision lenses).