View clinical trials related to Myopia.
Filter by:In this study 126 eyes in 63 patients with moderate bilateral myopia and astigmatism between -3 and -5 (SE difference between two eyes should not be more than 0.75 and the residual corneal thickness>350 μ ) were entered in the study. One eye went randomly under PRK with mitomycin C 0.02% in 15 min and then the other eye went under the operation without MMC. UCVA,BCVA, refractory error after the operation and the number of endothelial cells before and after the surgery would be compared in 6 months.
This study evaluates the intrastromal correction of ametropia with a femtosecond laser made by 20/10 PERFECT VISION. This laser generates a beam of ultrashort, infrared pulses which enables very precise cuts in the cornea. By these cuts lamellae of the cornea are separated locally, and in the consequence the curvature of the cornea is changed, and the correction of the diagnosed ametropia can be achieved. On the contrary to cuts which are generated with a sharp knife, the cuts generated when using a laser can be generated just inside the cornea without opening the surface of the cornea. This means the procedure is minimal-invasive. The study hypothesis is: Different types of ametropia can be corrected safely and on long-term by intrastromal cuts.
The purpose of this study is to analyze macular retinal thickness and macular volume using the spectral domain - optical coherence tomography (SD-OCT) in normal eyes and in eyes with various ocular diseases.
In this study, the investigators employed Visante-OCT (Carl Zeiss, USA), an anterior chamber optical coherence tomography, to monitor the change of anterior chamber dimensions. These data were correlated to anterior and posterior curvature changes collected with the Oculus Pentacam (Oculus Inc., Germany), a corneal topographer based on rotating Scheimpflug principle. To minimize the effect of convergence and excyclotorsion during examination, topical cycloplegic medication was used. The investigators hypothesized that if there is a link between ciliary muscle contraction and cornea curvature, installation of cycloplegic should result in widening of anterior chamber angle to angle distance and flattening of the cornea curvature data.
The purpose of this combined retrospective and prospective chart review analysis is to investigate the safety, efficacy, and predictability obtained via Laser-Assisted In Situ Keratomileusis (LASIK) and Advanced Surface Ablation (ASA) over a wide range of refractive errors The working hypothesis is that there will be no difference in clinical outcomes between patients treated with LASIK or ASA.
Glaucoma is presumed to be an axonal disease which starts at the lamina cribrosa. This assumption has led to the monitoring of the retinal nerve fiber layer thickness for the diagnosis and monitoring of progression of glaucoma. However, varying disc size, myopia and tilted discs affect the thickness of the retinal nerve fiber layer. This study aims to ascertain the ration of the retinal nerve fiber layer against full retina as a predictor of glaucoma diagnosis and progression.
Because the measurement of the retinal nerve fiber layer thickness is very sensitive to the position of measurement, it may be incorrect in patients with the tilted disc. In the present study, the corrected RNFL thickness by the optic nerve head configuration using the Cirrus HD OCT will be evaluated. If the corrected RNFL thickness is more sensitive to detect the localized RNFL defect, the present software should be upgrade to reflect the optic nerve head configuration.
Our study has three parts has three parts, and the main aim of the study is to find out if corneal hysteresis was associated with myopia or even a predictor of myopia poor control predictor: - Part 1 of our study: patients with anisomeropia whose spherical equivalent refraction as measured by cycloplegic autorefraction between the two eyes differ greater than 1.5 D. - Part 2 of our study: Minus spherical equivalent refraction as measured by cycloplegic autorefraction. - Part 3 of our study: patients with minus spherical equivalent refraction as measured by cycloplegic autorefraction who are under regular atropine for the treatment of myopia;patients who are prescribed with atropine treatment are in need of myopia control instead of for research interest
The purpose of this study is to test the hypothesis that myopia can be prevented by using a low concentration of atropine eyedrops once a week.
The overarching goal of our research study is to evaluate changes in visual function and optic nerve topography (the structure of the back of the eye) in patients with glaucoma (increased susceptibility to pressure inside the eye that can cause loss of vision) or those with an increased risk of developing the disease. The purpose of this study is to determine the best methods for detecting the presence or progression (worsening over time) of glaucoma in patients with and without myopia and its effects on daily and visual function and quality of life. With several sources of NIH and foundation funding over the last twenty years we have designed a robust research protocol to address the most challenging aspects of glaucoma management. The most recent focus of this research is 1) to improve our ability to detect open angle glaucoma in individuals with myopia and in individuals of European and African descent, 2) to determine whether monitoring of the retinal vasculature with new optical imaging instruments can improve glaucoma management and elucidate the pathophysiology of the disease, and 3) to differentiate between age-related changes and glaucomatous progression. The grants supporting this project include 3 NIH funded studies, 1) the University of California, San Diego UCSD -based "Diagnostic Innovations in Glaucoma Study" (DIGS funded since 1995): 2) the "African Descent and Glaucoma Evaluation Study" (ADAGES funded since 2002), 3) the Brightfocus Foundation National Glaucoma Research Program and 4) the UCSD-based "Diagnosis and Monitoring of Glaucoma with Optical Coherence Tomography Angiography" (funded since 2018). The ADAGES is a multi-center study with data collection also conducted at 2 other academic sites, the University of Alabama at Birmingham, and Columbia University. Enrolled healthy participants, glaucoma suspects and glaucoma patients are generally asked to return for two or more visits a year for several years. We then analyze whether the glaucoma patients are progressing and what factors influence their glaucoma status compared to healthy subjects and individuals suspected of having glaucoma.