View clinical trials related to Astigmatism.
Filter by:In this multicenter, prospective, interventional, single-arm clinical trial, the aim is to determine safety and efficacy of CLEAR using the FEMTO LDV Z8 in Chinese patients in China. The primary objective is to evaluate the visual outcome after CLEAR using the FEMTO LDV Z8 in myopia and astigmatic myopia at the time point, when stability of manifest refraction spherical equivalent (MRSE) is reached. The corresponding hypothesis is that the percentage of treated eyes with satisfactory Uncorrected Distance Visual Acuity (UCDVA) at the point when stability of MRSE is reached after CLEAR is at least 85% of all treated eyes. This hypothesis has been chosen in line with the recommendations of the "Checklist of Information Usually Submitted in an Investigational Device Exemptions (IDE) Application for Refractive Surgery Lasers" issued by the FDA. The secondary objectives are to evaluate the efficacy and safety with respect to stability, predictability, device defects and adverse events of CLEAR using the FEMTO LDV Z8 in myopia and astigmatic myopia during follow-up.
The main goal of this study is to compare traditional cataract surgery with two new technologies: the femtosecond laser and the new Active Sentry handpiece. The femtosecond laser is used in several fields of ophthalmology and allows to automate multiple key steps of cataract surgery. The new generation of handpiece called Active Sentry has the particularity to detect the pressure inside the eye in real time and to adjust it to avoid large variations. Theses technologies would potentially increase the efficacy and safety of standard cataract surgery. This study therefore aims at evaluating the differences in cumulative dissipated energy and endothelial cell loss between femtosecond laser assisted cataract surgery with the new Active Sentry handpiece compared to standard phaco with new (Active Sentry) or older handpieces (OZil).
surgical correction of ametropia. A number of improvements have been introduced to overcome the side effects and complications such as corneal haze, epithelial irregularities induced by wound healing, pain and delayed visual acuity recovery associated with PRK surgery. During traditional PRK, the corneal epithelium is mechanically debrided before stromal ablation is performed. Alcohol PRK is frequently used as an alternative to mechanical epithelial debridement and is considered simpler and faster. Transepithelial PRK (TransPRK) is a new method in which the corneal epithelium is photoablated by the laser in one step using a specific ablation profile. This study attempts to establish a means of quantitatively and objectively measuring corneal haze, using patented software based on optical coherence tomography (OCT) of the cornea. This will confirm or refute the hypothesis of a lower occurrence of corneal haze after TransPRK (experimental group) versus PRK with alcohol (control group). Each patient will have one eye randomised to one of the two groups being compared.
The AQUARIUZ ablation laser is a solid-state laser and has been CE approved for corneal surgery since March 2020 for the treatment of short- and longsightedness with and without astigmatism. The aim of this study is to collect the first clinical data. Safety and performance are examined here. The treatment with AQUARIUZ is comparable to treatments with an excimer laser, with the difference that these are operated with gas. Solid-state lasers and excimer lasers use the same process for tissue ablation, with a small difference in wavelength. This difference manifests itself in the lower involvement of water in the ablation process with the result of a gentler and safer treatment. Similar to excimer lasers for corneal surgery, the AQAURIUZ system (Ziemer Ophthalmic Systems AG) is equipped with a fast eye tracker (eye tracking system) to correct eye movements during the treatment. The shape of the removed portion of the cornea has an aspherical profile corresponding to the state of the art. The primary objective is to assess the safety of use of the AQUARIUZ corneal ablation laser for LASIK procedures in myopia and myopia with astigmatism. The secondary objective is to compare the predicted visual and refractive outcomes of LASIK procedures using the AQUARIUZ Ablation with clinical data. The study is planned in 3 phases to mitigate the inherent risk of a first in man study and to allow for verification and confirmation of the system correction factor at an early stage.
To assess the rotation stability of toric intraocular lenses between sitting or routine settings (sitting, going around) after cataract operation.
The purpose of this study is to compare developmental outcome for young children (12 to 35 months of age) with astigmatism meeting American Academy of Ophthalmology spectacle prescribing guidelines and who are prescribed and provided spectacles for either Full-Time wear (encouraged and reinforced) or Ad Lib wear (wear dependent on child acceptance).
The magnitude of posterior corneal astigmatism was considered negligible due to the smaller difference in the refractive index between the cornea and the aqueous . though ,neglecting the posterior corneal astigmatism lead to errors during calculation of the toric iols (over or under estimation ) . so we aim to determine the percentage of contribution of posterior corneal astigmatism to total corneal astigmatism in a sample of Egyptian population using scheimpflug imaging (Pentacam ).
MAIN OBJECTIVE: To assess the influence of residual astigmatism on visual acuity in the different lens foci in patients operated on for cataracts with a trifocal intraocular lens implant. SECONDARY OBJECTIVE: To study the influence of residual astigmatism on the visual quality of the patient in the far focus and to determine if there are differences of affectation in the two study groups.
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
Compared to laser-assisted in situ keratomileusis (LASIK), Photorefractive Keratectomy (PRK) is associated with more discomfort and requires more downtime. However, it is oftentimes considered the preferred method of refractive surgery for patients with dry eye syndrome, high refractive errors, thin corneas, or those with more active lifestyles who may be more prone to dislodging their LASIK flaps. We hypothesize that the use of bandage contact lenses soaked in proparacaine will decrease pain levels compared to solely the use of bandage contact lenses after PRK.