View clinical trials related to Astigmatism.
Filter by:The purpose of this study is long-term follow up of patients with corneal diseases to analyze the quality of surgical interventions and diagnosis. Corneal ectasia, especially keratoconus, is a corneal disease that leads to an irreversible loss of visual acuity while the cornea becomes steeper, thinner and irregular. For these patients, surgical intervention (e.g. corneal cross-linking) is performed, in case of disease progression. Overall, a long-term follow up is needed to evaluate an early disease progression as well as corneal stability after surgical intervention.
This study will be a 3-phase, 12-months, prospective,single arm, multicenter, open-label, non-comparative, clinical investigation conducted at up to 7 sites. Up to 20 subjects will be enrolled in phase I, up to 30 subjects in phase II, and up to 200 subjects in phase 3 to achieve up to 350 treated eyes.
The Use of the VisuMaxTM Femtosecond Laser Small-Incision Lenticule Extraction (SMILE) Procedure for the Correction of Myopia with or without Astigmatism study is a prospective, non-randomized, multicenter clinical study that will be conducted by the Navy Refractive Surgery Center, Naval Medical Center San Diego, CA in collaboration with the U.S. Air Force 59th Medical Wing, Wilford Hall Eye Center, TX, and the U.S. Army Warfighter Refractive Eye Surgery Program and Research Center, Fort Belvoir Community Hospital, VA.
This study sets out to evaluate the EpiMaster application software for use in predicting the refractive change induced by a trans-epithelial phototherapeutic keratectomy (TE-PTK) procedure in eyes with irregularly irregular astigmatism. If validation criteria are met during the observational phase, the software refractive prediction will be used to plan the refractive correction in TE-PTK treatments.
The investigational devices are approved intraocular lenses (IOL) intended to be implanted after phacoemulsification in individuals suffering from age-related cataract with the need of cataract surgery. Within the study, three different IOLs will be investigated and separately evaluated. Cataract surgery with IOL implantation will be performed in subjects who have signed an informed consent form. Postoperative examinations will be postoperative refraction, visual acuity, slitlamp examination, and rotation of the IOL within 1 hour, 1 week, 1 month and 4-7 months. In the Alcon Clareon toric and RayOne EMV toric groups, patients receive a toric IOL according to their preoperative astigmatism
This study is to compare the contrast sensitivity function and neural response to gratings before and after the orientation discrimination task in the astigmatism or amblyopia patients.
The purpose of the study is to compare the astigmatism reducing effect of a toric intraocular lens (IOL) (model MX60T - Bausch & Lomb) with that of limbal relaxing incisional surgery combined with a non toric IOL (model MX60 - Bausch & Lomb) in patients with corneal astigmatism between 1.0 and 1.5 diopters and also the effect of cylinder reduction on patient's quality of vision.
Comparison of the astigmatism reducing effect of a toric IOL with a non toric IOL in eyes with low corneal astigmatism.
The recently introduced toric V4c toric ICL (STAAR Surgical Company, Monrovia, CA, USA) has been designed with a 360-µm central hole to allow aqueous humor to flow without the need for an iridotomy. As far as the investigators certain, there have been not well-established prospective studies on the role of the V4c toric ICL for myopic astigmatism correction. Therefore, the present study aimed to investigate the clinical outcomes and rotational stability and to analyze factors that influence the rotational stability in V4c toric ICL implanted eyes prospectively.
To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.