View clinical trials related to Astigmatism.
Filter by:The goal of this observational study is to test whether surgeries for lenses designed to be implanted in the eye to correct refractive error can be done without the need for using viscoelastic substances that are used routinely nowadays to make it easier to introduce them inside the human eye and protect the inside of the eye during the operation. The main question it aims to answer is that is it safe to do the surgery without using them? to answer this question researchers will access recorded data of patients that underwent refractive surgeries in a private clinic since 2017 and compare them as two groups: those who underwent the traditional procedures and those who had it without the use of dispersive viscoelastics in regard to their vision before and after surgery, their ocular pressure and biomicroscopic analysis of the inside of their corneas before and after surgery.
To evaluate the visual and refractive outcomes after an intraocular lens (IOL) implantation in pediatric eyes with cataract and preexisting corneal astigmatism
The purpose of this post-market study is to describe the long-term safety and performance of Clareon Toric Intraocular Lenses (IOLs).
To evaluate the short-term efficacy and safety of scleral contact lens in the clinical treatment of patients with irregular astigmatism after corneal transplantation by analyzing ocular parameters and ocular surface conditions of patients after corneal transplantation.
The goal of this observational study is to learn about the difference of refractive outcomes between Artificial Intelligence and experienced surgeon predicting Nomogram assist SMILE surgical design and the influenced factors of refractive outcomes in patients who underwent Small Incision Lenticule Extraction(SMILE) at the Refractive Surgery Center of Tianjin Eye Hospital. The main questions it aims to answer are: - Compare the difference of refractive outcomes between Artificial Intelligence and experienced surgeon predicting Nomogram assist SMILE surgical design - Analysis the influenced factors of refractive outcomes
In modern cataract surgery, residual astigmatism continues to be one of the major factors influencing patients' visual quality and satisfaction. The goal of this study is to compare the clinical outcomes of femtosecond laser arcuate keratotomy in one eye and Toric intraocular lens implantation in the contralateral eye for astigmatism correction in patients undergoing femtosecond laser-assisted cataract surgery. The study is a prospective randomized comparative study. Patients with binocular regular corneal astigmatism ranging from 0.75 to 3.00 D will be recruited. The patient will randomly receive femtosecond laser arcuate keratotomy in one eye and receive Toric intraocular lens implantation in the contralateral eye. Long term evaluation will be performed to compare the visual acuity, subjective manifest refraction, and corneal topography between groups.
Small incision lenticule extraction (SMILE) is a refractive intrastromal procedure for myopia and myopic astigmatism correction. Most of the studies evaluating astigmatic correction by SMILE reported astigmatic under-correction, especially in high degrees of astigmatism. This under-correction could be due to: first, the active eye tracker or the iris registration is not yet available to overcome the cyclotorsion that occurred during the treatment with the VisuMax femtosecond laser system (Carl Zeiss Meditec, Jena, Germany) which could be overcome by manual compensation technique, especially in higher degrees of cylinders (> 1.5 diopters (D)). Second, in patients with small lenticule diameters, the more abrupt change in thickness at the edge of the treated area could induce more stromal and epithelial healing in this area. Thus, the astigmatic correction would be less effective with small than large lenticule diameters for similar high preoperative astigmatism. This study assessed the outcome of using a 0.5 millimeter (mm) larger lenticule diameter in the fellow eyes of myopic astigmatic correction SMILE participants. This assessment included the safety and effectiveness indices, the refractive and visual outcomes, the contrast sensitivity, and some morphological outcomes such as corneal curvature and epithelial and corneal thickness.
Software refraction in the mobilerone for myopia and astigmatism is a novel medical device for myopia adults and elder children with or without astigmatism. And the investigators would like to test its accuracy and efficacy as well as safety.
Determine if Total30 for Astigmatism contact lenses (CLs) provide a comfortable wearing experience all day. CL discomfort affects most CL wearers with discomfort consistently topping the reasons why established CL wearers drop out of CLs. In fact, studies have consistently found that the frequency of CL dropout is around 20% with this dropout frequency staying relatively stable over the past 20 plus years. This static frequency of CL dropout is surprising since there have been a number of dramatic soft CL innovations during this time frame (e.g., widely available daily disposable CLs, silicone hydrogel CL materials with high oxygen transmissibility, new CL surface coatings).
The objective of this orthokeratology study is to evaluate the safety and effectiveness of the Arise Orthokeratology Lens with non-spherical posterior peripheral curves