View clinical trials related to Myopia.
Filter by:To test the hypothesis that correction with bifocal spectacle lenses rather than single-vision lenses will slow the progression of myopia in children with near-point esophoria. The primary outcome variable is cycloplegic refraction as measured with an automated refractor. Axial length is measured with ultrasound in order to test the corollary hypothesis that use of bifocals will slow ocular growth in these myopic children. We will also examine the amount of close work performed by subjects and the degree of parental myopia as factors that may influence myopia progression.
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).