View clinical trials related to Myopia.
Filter by:Macular foveoschisis (MF) is a common complication of pathological myopia, which is characterized by choroid-retinal degeneration and vision impairment. Although pars plana vitrectomy (PPV) is the primary method for MF treatment, there is still a large proportion of recurrent MF due to the extremely long global axial length and posterior staphyloma. Macular buckling (MB) surgery aims at counteracting the traction exerted by the posterior staphyloma, and has been proven an effective method for treating MF. Optical Coherence Tomography (OCT) is widely used for the structural analysis of MF. Multifocol electroretinogram (mfERG) is an objective examination for visual evaluation. To our knowledge, there is a lack of data on the comprehensive visual function evaluations of MF patients associated with OCT findings. Our clinical trial aims to provide the structural and functional relationship in MF patients undergoing MB surgery, and find out potential factors to determine the visual prognosis.
This pilot study will evaluate the visual response to infrared (IR) in humans after dark adaptation. The investigators plan to determine which wavelength and intensity the human eye is most sensitive too, using a broad spectrum light source and wavelength-specific bandpass filters. The investigators will then evaluate the electrophysiologic response in healthy humans to IR, followed by studies in those with specific retinal diseases. The long-term goal of this research is to better understand the role that IR plays in visual function, and whether this can be manipulated to allow for vision in certain retinal pathologies that result from loss of photoreceptor cells. The investigators central objective is to test the electrophysiologic response to IR in the dark-adapted retinal and visual pathways. The investigators central hypothesis is that IR evokes a visual response in humans after dark adaptation, and the characteristics of this response suggest transient receptor potential (TRP) channel involvement. The investigators rationale is that a better understanding of how IR impacts vision may allow for an alternative mechanism for vision in a number of diseases that cause blindness from the degradation or loss of function of photoreceptor cells. The investigators will test the investigators hypothesis with the following Aims: Aim 1: To determine the optimal IR wavelength for visual perception in dark-adapted human participants. The investigators hypothesize that the healthy human eye will detect IR irradiation, with a maximum sensitivity at a specific wavelength. Using a broad-spectrum light source with wavelength-specific bandpass filters, the spectral range of visual perception to IR will be evaluated. The same will be done on colorblind participants. Aim 2: To test the electrophysiologic response to IR in healthy humans after dark adaptation. The investigators hypothesize that IR will elicit an amplitude change on electroretinography (ERG) and visual evoked potential (VEP) responses after dark adaptation in healthy human participants. Participants will be tested with both test modalities to evaluate their response to IR. Aim 3: To test the electrophysiologic response to IR after dark adaptation in humans with certain retinal diseases. Participants with retinitis pigmentosa, age related macular degeneration and congenital stationary night blindness, will be tested. Results will be compared to baselines and to those of healthy participants. The investigators hypothesize that there will be a response to IR on ERG and VEP, which will provide clues to the retinal cell layer location of the response to IR and the nature of potential TRP channel involvement.
The purpose of this study is to determine whether Eye Health Intervention can obviously reduce and delay myopia onset and development and improved the awareness rate of knowledge apparently .
Prospective study aiming to measure central ablation depth during excimer laser surgery in myopic patients operated with femtosecond laser assisted LASIK with intraoperative OCP, before and after laser ablation. This measurement will be compared with pre and 1 month postoperative topography differential pachymetric measurements.
The photorefractive keratectomy was the first correction mode refractive laser. It's a photo-ablation of a predetermined thickness of anterior corneal stroma. Debridement of epithelium can be done either mechanically (m-PRK) or by laser (trans-PRK). Trans-PRK has a lot of interests: facility and speed of procedure as well as suppression of human variable. Very good results are obtained by m-PRK. The aim of this study is to show equivalence or non inferiority of trans-PRK over conventional m-PRK in terms of safety and refractive efficiency
43 Subjects (43 eyes) qualified for participation will undergo the required screening procedures to determine study eligibility. The surgical protocol involves applying riboflavin 0,22% to 0,25 % up to 20 minutes . Then, the eyes will be exposed to UVA (ultraviolet A) light with the KXL II system according to the programmed treatment pattern. All use of the KXL II system will be in accordance with the general instructions in the operator's manual. All subjects will be evaluated at screening, Day 3, and 1, 3, 6 ,12 and 24 months after treatment. Manual keratometry, manifest refraction, uncorrected visual acuity, best corrected visual acuity, slit lamp biomicroscopy, pentacam measurements and placido disc topography (TMS), will be obtained at baseline and at appropriate times after the treatment.
The purpose of this study is to determine whether less frequent dosing of atropine drops may be as effective as daily dosing for the treatment of progressive myopia.
Myopia, the most common human eye disorder, is a phenomenon characterized by an unconstrained elongation of the eye globe There are number of theories concerning the environmental effect on the emmetropization process, most are related to childhood exposure to outdoor activity, near work and sleep with night light. Studies in lab animals found an association between intensity of ambient lighting and myopia development. In this study, the investigators will examine the ambient light in kindergarten and schools and their relation to refractive error. Diurnal luminance in kindergarten and school class room will be measured and correlated to biometric measures such as refraction, axial length and keratometry.
The aim of this study is to compare the subjective performance of the comfilcon A contact lens against lotrafilcon B contact lens after 4 weeks of reusable lens wear.
In this study, ocular discomfort following intravitreal injection in naïve patients will be studied, as well as the efficacy of wetting agent (Optive eyewash) to prevent ocular discomfort.