View clinical trials related to Astigmatism.
Filter by:The primary objective of this study is to collect safety and effectiveness data for the Technolas Teneo 317 Model 2 excimer laser for LASIK correction in participants with myopia and myopic astigmatism.
The aim of this prospective study is to evaluate the clinical performance of habitual wearers of Clariti Toric lenses after a refit with Avaira Vitality Toric lenses for 1-month of daily wear.
An evaluation of the clinical performance of the 1-day toric test contact lens compared to the 1-day toric control contact lens over one hour of lens wear.
The primary objective of this study is to evaluate the safety and effectiveness of performing 0.50 D cylinder correction on the RxSight Light Adjustable Lens (LAL) in patients who have undergone implantation with the FDA approved, commercially available LAL.
This study will be a prospective, multicenter, bilateral, comparative, three-way masked (Sponsor, subject and evaluator), randomized clinical investigation conducted at up to 15 sites. Up to 300 subjects will be enrolled to achieve approximately 270 bilaterally implanted subjects, resulting in approximately 244 evaluable subjects (122 per lens group) at 6 months. After informed consent is obtained and confirmation that all eligibility criteria are met, the eye(s) may be treated according to randomization. After signing the informed consent form, subjects meeting all eligibility criteria will be randomized in a masked fashion to a treatment group: either the investigational IOL Model ZFR00V or the control IOL Model ZCB00. Prior to randomization, the investigator will choose which eye to operate on first for each subject at his/her discretion based on his/her standard clinical practice (e.g., the eye with the worse cataract, poorer best corrected distance vision and/or more severe optical/visual complaints). All subjects are intended to have bilateral cataract surgery with the second eye surgery occurring after the 1-week postoperative exam for the first eye, but no more than 30 days after the first eye surgery. All subjects will be examined through 6 months postoperatively according to the visit schedule
In the past two decades, the femtosecond laser (FSL) technology has been introduced in the corneal refractive surgery filed, and brought a remarkable innovation. It can make tissue dissection through photodisruption and plasma cavitation. Initially, the FSL was used predominantly to make a corneal flap when performing laser in situ keratomileusis (LASIK), which is followed by stromal ablation using excimer laser. A new surgical technique called femtosecond lenticule extraction (FLEx) has been developed that uses only FSL to dissect two interfaces to create refractive lenticule and then remove it, which is very similar with LASIK. Small incision lenticule extraction (SMILE) which is the advanced form of all-in-one FSL refractive technique does not make a corneal flap rather make small incision where the separated refractive lenticule is removed through, and the upper part of the corneal tissue is called cap. Since the clinical outcomes of SMILE were firstly published in 2011, SMILE has been widely used for correction of myopia or myopic astigmatism worldwide. SMILE provides excellent visual outcomes and has advantages including a lesser decrease in corneal sensitivity and absence of flap related complications compared to LASIK. The vector planning method is newly developed astigmatism correction method, which combines refraction astigmatism in 60 % emphasis and corneal astigmatism in 40 % emphasis. The vectorial difference between corneal astigmatism and refractive cylinder at the corneal plane is ocular residual astigmatism (ORA). In normal eyes treated for myopic astigmatism, the ORA typically ranges from 0.73 to 0.81 D. The eyes with high ORA resulted in inferior clinical outcomes after corneal refractive surgery including LASIK, LASEK, and SMILE. The vector planning method was effective in LASIK according to previous study. Therefore we try to confirm the efficacy of vector planning method in SMILE.
Single-center, open-label, prospective study in healthy volunteers desiring refraction for correction of visual acuity to compare a handheld device supported by a mobile application with the phoropter and autorefractor.
The objectives of this study are to evaluate the safety and efficacy of a treatment regimen for high myopia and myopic astigmatism: LASIK followed by crosslinking performed with the KXL Crosslinking-System and VibeX Xtra (Riboflavin Ophthalmic Solution, Avedro, USA), as compared to LASIK alone, with regards to regression of refractive outcome, as measured by manifest refraction spherical equivalent (MRSE) and keratometry.
This is a multicenter, non-comparative trial following participants implanted bilaterally with the Mini WELL Toric Ready intraocular lens (IOL) for 6 months after the second eye implant. The objective of the study is to evaluate the clinical performance of the Mini WELL Toric Ready intraocular lens (IOL), in particular, visual performance and rotational stability at 6 months following the second eye implantation in participants suffering from bilateral cataract with corneal astigmatism. There are 2 hypotheses: - Rotational Stability: the rotation of the Mini WELL Toric Ready IOL compared between Visit 0a (the day of surgery) and Visit 4 (120 180 days post-operative follow-up) shall be less than ±10° in 90% of the cases. - Severe Visual Distortions: the rate of severe visual distortions for the Mini WELL Toric Ready IOL reported at 6 months postoperative will be less than 10 percents.
To determine clinically significant difference in results obtained from cataract surgery using IA. One eye will receive aphakic measurements only and the fellow eye will receive aphakic and then pseudophakic measurements when implanting a toric IOL.