View clinical trials related to Myopia.
Filter by:This study aims to compare effects in retardation of myopia progression of combined ortho-k and 0.01% atropine therapy with those of ortho-k alone.Myopia control methods mainly focus on optical and pharmaceutical interventions . Currently, overnight-wear orthokeratology (ortho-k), is used extensively in Hong Kong with approximately 50% retardation effect. Pharmaceutical methods have focused on the use of atropine eye drops to slow myopic progression.The use of 1% atropine was limited by the manifestation of side effects and rebound effect.However, both side effect and rebound effect was minimal with 0.01% atropine.It was suggested that 0.01% was the optimum concentration for controlling myopia.The mechanisms of neither ortho-k nor atropine in myopia control are fully understood.It is believed that ortho-k and atropine act via different mechanisms.It is possible that by combining these two methods, additional retardation of myopia progression could be achieved.
The objective of this study is to evaluate the safety and effectiveness of the Bausch + Lomb samfilcon A soft (hydrophilic) contact lens, a new silicone hydrogel contact lens, compared to the Bausch + Lomb PureVision® soft contact lens when worn for 7-day extended wear by adapted soft contact lens wearers.
This study included patients who visit for refractive surgery (photorefractive keratectomy, photorefractive keratectomy with with corneal collagen cross linking, laser in situ keratomileusis, small incision lenticule extraction), phakic Intraocular Lens implantation (Implantable Collamer Lens, artiflex), and cataract surgery. Patients will be examined whether iris recognition scanner of smartphone works before and after surgery. In addition, before and after pupil dilation (5mm, 6mm, 7mm, 8mm), patients will be examined whether iris recognition scanner of smartphone works well.
This study aims to compare the clinical performance of the somfilcon A, nelfilcon A II 2 and omafilcon A II 2 daily disposable contact lenses.
This study aims to compare the clinical performance and subjective acceptance of the narafilcon A lens with the stenfilcon A lens when used on a daily wear, daily disposable basis.
The aim of this study is to determine the clinical performance of comfilcon A in comparison to senofilcon C.
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