View clinical trials related to Astigmatism.
Filter by: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).
Demonstrate that refraction measurements from the device agree with refraction measurements from a phoropter within clinically meaningful limits.
The objective of this orthokeratology study is to evaluate the safety and effectiveness of the Arise Orthokeratology Lens with non-spherical posterior peripheral curves
The primary objective of this study is to evaluate the axis orientation of LID226397 toric contact lenses.
To subjectively evaluate wearing experience in the T30fA lens among subjects who were already satisfied with their Biofinity Toric lenses.
The objective of the study is to compare the clinical performance of two monthly toric silicone hydrogel contact lenses in habitual wearers, when worn for 1-month each.
The objective is to compare the percentage of monocular UDVA -0.1 logMAR (20/16) outcomes for each planning strategy (Phorcides and manifest refraction) at the 3-month post operative visit.
The objective is to determine the percentages of past toric CL wearers (who dropped out of contact lens wear due to dissatisfaction with comfort or vision) who are satisfied with the comfort and vision of DT1fA contact lenses.