Active clinical trials for "Astigmatism"

Comparison of the astigmatism reducing effect of a toric IOL with a non toric IOL in eyes with low corneal astigmatism.

Astigmatic keratotomy (AK) is used to treat numerous refractive disorders, including congenital astigmatism, residual corneal astigmatism at the time of or following cataract surgery, post-traumatic astigmatism, and astigmatism after corneal transplantation. Within the past few years, much consideration has been given to an evolutionary variant of the procedure, the limbal relaxing incision (LRI). By moving the incision farther to the periphery, cataract surgeons can safely and predictably remediate mild to moderate amounts of regular astigmatism at the time of cataract surgery by performing this incisional technique. Recent technological developments have shifted ophthalmologist's attention from manually created LRIs and astigmatic keratotomy procedures to femtosecond laser-guided procedures. Femtosecond lasers offer superior incisional accuracy and reproducibility coupled with minimal effects on collateral tissues, achieving levels of safety and reproducibility exceeding those of mechanical techniques. A major clinical application of the femtosecond laser is for creating arcuate incisions that have a precise and accurate length, depth, angular position, and optical zone.

The main purpose of this study is to evaluate the use of limbal relaxing incision (LRI) for astigmatic correction. LRI is a procedure where a pair of incisions is made in the peripheral part of the cornea so as to alter its shape and improve the focusing power of the eye.

The objective is to conduct a contralateral prospective clinical study to compare the safety, efficacy, and quality of vision of the STAAR Surgical Co. Toric Implantable Contact Lens TICL) versus Custom Laser Vision Correction (Q-LASIK) in human eyes for the correction of myopia with astigmatism.

This study evaluates the Rayner T-flex Toric IOLs for spherical and astigmatic correction, and rotational stability in cataract surgery. 50 patients with cataract and corneal astigmatism >= 2 diopters will undergo cataract surgery, with implantation of Rayner toric intraocular lens. Post-operative examination will include IOL axis measurements and refraction.

The investigational device is an approved femtosecond laser (FSL) device with an integrated imaging system to perform certain steps of the cataract procedure including arcuate incisions (AI) correcting astigmatism, also referred to as arcuate keratotomy (AK). The FSL will perform anterior capsulotomy and lens fragmentation in individuals suffering from age-related cataract with need of cataract surgery and additionally perform arcuate keratotomy in individuals with more than 1.0 Diopter (dpt) of astigmatism. Cataract surgery will be performed in subjects who have signed an informed consent form. Postoperative examinations will be implemented in accordance with the approved Investigational Plan on subjects and includes: postoperative refraction, visual acuity, slitlamp examination, and corneal topography

This phase IV study is an open, prospective, single-center, single-surgeon bilateral eye study to investigate the bilateral uncorrected intermediate visual acuity of presbyopic hyperopic patients, who have been treated with Presbyopia Algorithm SUPRACOR.

Randomized, bilateral, cross-over dispensing study of a standard and VR800 refraction and associated spectacle lenses.

Comparison of LASIK outcomes using 3 different lasers and a total of 5 different treatment platforms.

Correlating the accuracy of a refraction done over telemedicine to that of a standard refraction, with a study hypothesis that the results will be equivalent.