Active clinical trials for "Astigmatism"

Background and Rationale: LASIK has been among the highest satisfaction rates of surgical procedures, ranging from 82%-98%. Different ablation profiles have been developed over the years. The purpose of this study is to validate this novel measurement by comparing the visual outcomes when the TMR is used in myopic astigmatic LASIK to using the standard manifest refraction or the Topolyzer measurements alone. Objectives : To evaluate the safety, efficacy and predictability of topography-guided myopic LASIK with three different refraction treatment strategies.

This clinical phase IV study is an open, prospective phase IV study and acts to evaluate the effectiveness of the femtolaser-assisted astigmatic keratotomy.

To demonstrate that wavefront-guided LASIK with measurements from iDesign is safe and effective in the treatment of mixed astigmatism.

The purpose of this study is to compare visual acuity, safety, predictability, corneal biomechanics, dry eyes, and nerve-morphology after all femtosecond laser refractive lenticule extraction. Approximately 30 to 40 patients with moderate to high myopia will randomly (after ocular dominance) receive ReLEx flex in one eye, and ReLEx smile in the other.

The purpose of the study was to assess the efficacy of the Allegretto Wave excimer laser and the wavefront optimized ablation profile in correcting primarily non-anterior astigmatism faults, following laser in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).

To evaluate the short-term changes in ocular surface measures and tear inflammatory mediators after lenticule extraction (FLEx), laser in situ keratomileusis (LASIK) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) procedures.

This study will include patients who will undergo PRK in both eyes, for each patient each eye will be randomly allocated to one of 2 procedures: topography-guided ablation in one eye (group I) and Q-factor customized ablation in the other eye (group II). Alcon/Wavelight Light Laser Technolo¬gie (GmbH, Erlangen, Germany) will be used for photoablation. The wavelight Topolyzer (Wavelight AG, Erlan¬gen, Germany)and CSO Sirius scheimpflug camera combined with Placido corneal topography (CSO, Florence,Italy) will be used before and 1, 3 and 6 months after PRK. Refrac¬tive visual outcomes and corneal aberration changes will be compared between the two treatment modalities.

The most common causes for irregular cornea (IC) in hospital contact lens practice are Keratoconus (KC) and related cornea thinning disorders. These conditions cause mild to marked impairment of vision and cannot be effectively corrected by spectacles and soft contact lenses. The gold standard in the management of KC is Corneal Rigid Gas Permeable contact lenses (corneal lenses), which correct approximately 90% of the corneal irregularity. Compared with a normal cornea, the cornea in KC is irregular and this results in a compromise to the fit of rigid corneal lenses. Specifically, they bear on the cornea and this, together with the vulnerability of the cornea in KC, are implicated in corneal scarring, and disease progression as well as a significantly reduced vision related quality of life (QoL) in KC compared with corneal lens wearers who have no KC. In cases where the compromise fit of corneal lenses proves problematic, large diameter Scleral RGP contact lenses (scleral lenses) may be used as a problem solver. Unlike the smaller corneal lenses which bear on the cornea, the scleral lenses completely bridge over the cornea and bear on the sclera. The aim of this research is to investigate the performance of scleral lenses in KC participants who habitually wear corneal lenses. The research question: is there a measurable difference in the visual performance and visual quality of life in participants with Irregular cornea disorders like keratoconus and other related conditions, who habitually wear corneal lenses in comparison with scleral lenses.

the purpose of this study was to assess the efficacy of custom made toric intraocular lens implantation in patients with simultaneous post-DALK high corneal astigmatism and cataract.

A study to demonstrate the safety and effectiveness of wavefront laser refractive surgery treatments for hyperopia and astigmatism.