View clinical trials related to Pseudophakia.
Filter by:Targeting of post-cataract refraction depends mainly on the prediction of the post-operative lens position, but also on the post-operative refraction itself. Hence, aim of this study is to evaluate the agreement and variability of subjective refraction performed by two independent examiners, autorefraction, and wavefront aberrometry in pseudophakic patients after uneventful cataract surgery.
Angle Kappa is considered a potential factor in explaining suboptimal outcomes with intraocular lenses (IOLs), particularly multifocal IOLs. Some evidence suggests this is not the case. This study was designed to investigate correlations between angle kappa and post-surgical outcomes with a trifocal IOL.
Usually following cataract surgery patients would expect to have normal distance vision and not require the use of distance glasses. However, in clinical practice desired vision post cataract surgery is not achieved sometimes. In such cases a piggyback lens is used to enhance the visual outcome. This lens is placed in the ciliary sulcus (space between the iris and the lens). Often this piggyback lens is not the best fit for the ciliary sulcus space and it moves. This study will be using ultrasound biomicroscopy to measure the ciliary sulcus dimensions pre and postoperatively to estimate the normal anatomy and it's variations. Patients in this study will be randomised as to which way the intraocular lens is placed in the eye (horizontally or vertically) at the time of their cataract surgery. Patients requiring cataract surgery in both eyes will be identified from the Eye Hospital at the Royal Sussex County Hospital. Patients will be in the study for up to 6 months from being identified as suitable through to the operation in the 2nd eye and a final study visit.
Cataract surgery involves replacing milky lens with a plastic intraocular lens. This plastic lens can be either monofocal (fixates for distance or near without glasses), extended depth of focus (EDOF)(fixates for intermediate and distance vision only without glasses) or multifocal lenses (fixates for distance, intermediate and near vision without glasses). However, EDOF and multifocal lenses are known to produce glare and halos. Tecnis Eyhance (Johnson & Johnson, USA) is a monofocal IOL which give added intermediate vision without employing EDOF or multifocal technology and hence induces no glare and halos. Whereas monofocal IOLs such as RayOne do not give intermediate vision. The objective is to assess visual and optical performance of Tecnis Eyhance versus Rayner RayOne in a prospective, randomized, comparative bilateral study. The proposed study will be the first study comparing the new technology monofocal Eyhance with conventional RayOne Rayner lens to assess the added benefits of Eyhance technology at multiple visits until 3 months after the surgery. Patients attending the clinics with cataracts will be invited to participate in this randomised study. They will be randomised to receive either Eyhance or RayOne in both eyes through surgeries performed not more than 2 weeks apart. The patients will be followed up at 1 and 3 months in the research clinic to assess the uniocular and binocular vision, spectacle prescription, a simple non-invasive scan to look at any distortions in the optics of the eye (wavefront aberrometry) and questionnaire for assessing subjective outcomes, glare and halos.
To compare (low contrast) visual acuity (VA) and contrast sensitivity (CS) - both at intermediate distances under nighttime driving conditions in a driving simulator between patients with bilateral EYHANCE IOLs OR bilateral conventional monofocal IOLs. Visual function testing in the driving simulator will be assessed without AND with (static) glare. Additionally: Assessment of individual response times, scanpath characteristics, evaluation of test retest reliability and self-evaluation of (intermediate) vision and visual impairment related to glare.
The investigators are proposing this research project to: 1. Screen a set of patients after normal cataract surgery with a single focus lens aimed at good distance vision at 3 months after surgery to identify patients who are able to see and read well without glasses. 2. Identify the combination of factors responsible for this phenomenon in the patients who are achieving this. Potentially eligible patients will be given an invitation letter and patient information sheet on the day they arrive for surgery. They will then be asked if they are happy to be contacted by phone 2-4 weeks post-surgery with a view to booking them into an additional research visit at 3 months after their surgery. At 3 months after surgery they will have their un-corrected vision checked. They will also have their reading speed assessed without any glasses. They will undergo a through refractive check by an optometrist to assess the power of the spectacles (if needed) and following this they will have a scan of the eye (a technique known as wave front analysis which uses very sophisticated optics) to capture the optical distortions in the structures of the eye. If this study is able identify factor/s responsible for giving good unaided reading and distance vision then this factor can be reproduced in eyes undergoing cataract surgery. This will mean that the patients can have an increased option of spectacle independence without the need for expensive multifocal IOLs and their associated side effects such as glare and halos, particularly at night.
The current study aims to assess the use of pilocarpine and brimonidine to improve near visual acuity in patietns with monofocal intraocular lenses. Thirty-three subjects with be enrolled and baseline visual acuity with be measured at near and distance. This will be compared to visual acuity after drop administration over 6 hours. A quality of life questionnaire will also be evaluated.
A study to assess the utility of human polarization pattern perception for the detection, diagnosis and monitoring of eye disease
Influence of different ophthalmic conditions after cataract surgery (extended range of vision IOL (EROV) with micromonovision, minimonovision with standard IOL and single focus distance vision with standard IOL) on reading quality.
To evaluate long-term intraocular lens (IOL) decentration and tilt in eyes with pseudoexfoliation syndrome (PES) following cataract surgery using Visante anterior segment OCT and iTrace Visual Function Analyzer.