Loading clinical trials...
Loading clinical trials...
Showing 1-20 of 59 trials
NCT07372911
Keratoconus causes irregular astigmatism and reduced vision. Epi-off corneal crosslinking (CXL) stabilizes the cornea but often leaves higher-order aberrations uncorrected. This randomized, parallel-group trial compares corneal wavefront guided photorefractive keratectomy (corneal wavefront guided PRK, 50 µm therapeutic ablation) combined with accelerated epi-off CXL versus epi-off CXL with epithelial removal by phototherapeutic keratectomy (PTK) using a Schwind AMARIS excimer laser, in adults with keratoconus. The primary endpoint is change in best-corrected distance visual acuity (logMAR) at 12 months. Key secondary endpoints include Kmax, corneal higher-order aberrations, manifest refraction, Scheimpflug densitometry (haze) and Fantes grade, Corvis ST biomechanics, NEI VFQ-25, and endothelial cell density by non-contact specular microscopy at 1, 3, 6 and 12 months.
NCT06451718
This Study is a First In Human clinical investigation addressed to evaluate the safety and efficacy of a novel intra-corneal nitinol device (Investigational Medical Device: GROSSO® implant) for the treatment of advanced keratoconus disease of the eye.
NCT06818461
To evaluate corneal biomechanical changes using the Corvis ST in patients who have under-gone LASIK, PRK, and corneal cross-linking (CXL).
NCT02118922
We have developed novel Brillouin microscopy and we are testing its potential for keratoconus and ectasia diagnostics. We plan to perform axial scans of the cornea in human volunteers in order to compare biomechanical properties of Keratoconus vs. Normal corneas and compare biomechanical properties of post-LASIK ectasia vs. normal corneas.
NCT04094090
To evaluate the safety and effectiveness of the PXL Platinum 330 system for performing corneal cross-linking (CXL) for the treatment of ectatic disorders.
NCT03504800
This main goal of this study is to improve the detection, classification, monitoring, and treatment of irregular corneas due to keratoconus, warpage, dry eye, scar, stromal dystrophies, and other corneal conditions. The primary goal will be achieved by using optical coherence tomography (OCT) to: 1. Develop an OCT-based system to classify and evaluate corneal-shape irregularities. 2. Develop OCT metrics for more sensitive detection of keratoconus progression. 3. Develop OCT-and-topography guided phototherapeutic keratectomy (PTK) for irregular corneas.
NCT04570020
The purpose of this study is to see if OCT technology can optimize scleral contact lens fittings. Subjects with keratoconus, post-penetrating keratoplasty (PK), post-LASIK ectasia, post-radial keratotomy (RK), or a variety of anterior surface disorders requiring scleral lens fittings will be considered for enrollment. For each study eye, a clinically-selected scleral lens fit will be compared against an OCT-selected lens fit. The quality of each lens fit will be determined by flourescein exam at the slit lamp. Apical clearance, limbal clearance, conjunctival compression, and lens edge lift will be assessed. A lens that satisfies all four criteria will be considered satisfactory.
NCT06914973
The cornea, as the outermost refractive structure of the eye, plays a critical role in maintaining clear vision. Its transparency and structural integrity are essential for optimal visual function. Among the layers of the cornea, the corneal epithelium is of particular interest due to its dynamic nature and its ability to remodel in response to various physiological and pathological conditions. Accurate and repeatable measurement of corneal epithelial thickness (CET) is therefore crucial for diagnosing and managing corneal diseases, such as keratoconus, and for planning refractive surgeries Keratoconus, a progressive corneal ectatic disorder, is characterized by thinning and protrusion of the cornea, leading to irregular astigmatism and visual impairment. Early detection and monitoring of keratoconus rely heavily on precise corneal imaging, including CET mapping. While AS-OCT has shown promise in evaluating CET in both healthy and keratoconic eyes, the repeatability of these measurements must be thoroughly evaluated to ensure their clinical utility Early diagnosis with subsequent corneal crosslinking (CXL) can slow-down or stop keratoconus progression.9 Identifying subclinical keratoconus is extremely important in refractive surgery screening to avoid iatrogenic ectasia. Anterior and posterior corneal topography combined with total cornea thickness measurements and localisation of the thinnest area are the parameters used commonly for diagnosing and staging of corneal ectasias. Recently, epithelial thickness is also added as an additional parameter and is shown to be useful for both early diagnosis and grading of keratoconus Corneal imaging is an essential tool in modern eye care. Initially, the curvature of the anterior corneal surface constituted the ground for the estimation of corneal optical properties and diagnosis of ectatic disorders like keratoconus. Gradually the importance of the posterior corneal curvature as well as its thickness gained significance. In recent years, new imaging devices allowing fast and high-resolution imaging of the entire anterior segment, cornea included started to emerge. The main advantages of the new generation Anterior Segment Optical Coherence Tomography (AS-OCT) are their superior acquisition speed, improved optical resolution (axial and transversal), as well as scanning depth and field of view . High-resolution imaging of the cornea with AS-OCT provides thickness measurements individually for epithelium and stroma individually. Measuring corneal epithelial thickness adds information that could be of value in early diagnosis, progression evaluation and maybe even for a more complete understanding of the pathophysiology of this disease. It has been shown that changes in the corneal epithelial thickness could be a sensitive tool for early keratoconus detection as well as for the assessment of the disease progression. Precise measurements of the epithelial thickness are therefore important for keratoconus diagnosis and follow-up. AS-OCTs have high axial resolution and studies have shown that these instruments provide repeatable epithelial measurements both in central and peripheral cornea. With an additional lens (anterior segment module), posterior segments OCTs can also be used to measure corneal parameters including epithelial thickness1and previous studies have shown that these modules can also produce precise epithelial thickness measurements in healthy corneas and in keratoconus. There is only limited information on how the precision of epithelial measurements with the anterior module in posterior segment OCTs compares to the precision of epithelial measurements with AS-OCTs Aim of this study Detect early-stage keratoconus by identifying suitable epithelial thickness changes before topographic abnormalities appear . \- Provide higher accuracy compared to traditional topography by offering high-resolution cross-sectional imaging
NCT04667572
Safety and Effectiveness of the PXL-Platinum 330 System for Corneal Collagen Cross-linking in Eyes With Corneal Thinning Conditions
NCT05748847
Keratoconus is a corneal degenerative disease associated with loss of best-corrected visual acuity. The use of intrastromal corneal ring segment implants is indicated to regularize the cornea and to reduce aberrations.
NCT06565091
The purpose of this clinical investigation is to evaluate the clinical utility of a multifunctional measuring device for Ophtalmology. The results of this clinical investigation will be used to refine and validate the device design. 378 participants total will be included in the trial, each having only one visit at the investigation center.
NCT05516004
This study study is to determine the effectiveness of cornea cross linking in patients with Keratoconus or other cornea thinning conditions.
NCT04698590
Aberrations are the spreading of light from a point focus. Aberrations of the eyes can be objectively evaluated with a wavefront aberrometer. Lower order aberrations such as defocus and astigmatism can be corrected with glasses and traditional/disposable soft contact lenses. Patients with ectatic corneal disease, such as keratoconus, or irregular astigmatism cause by surgery, trauma or disease, experience vision that is unlikely to be adequately corrected with glasses or disposable soft contact lenses due to higher order aberrations (HOA). HOA's cause halos, flare, glare, starbursts, doubling, smearing or ghosting of vision. Specialty contact lenses, such as scleral lenses, can be used to mask the irregularity of the cornea, reducing HOA's and improving vision. In many patients the resultant vision, though improved, still has some level of residual HOA's affecting the quality of vision. Custom scleral lenses with customized wavefront guided optics can be used to reduce residual HOA's and improve vision further. These lenses have been referred to as higher order aberration correcting scleral lenses or HOA correcting sclerals and wavefront guided scleral lenses or WFG sclerals.
NCT06312163
The goal of this Prospective, single-site, cohort study is to validate rigid gas permeable corneal contact lens (RGP) designs for keratoconus derived from combining the data from corneal topography scans and contact lenses ordered in patients with keratoconus (KC) attending a UK tertiary NHS Hospital contact lens clinic. The main questions it aims to answer are: * Does a Scheimpflug topography derived RGP contact lens design for keratoconus have the equivalent overall contact lens fit as the patients' own lens? * Is the number of trial lenses required to fit a patient is reduced compared to standard practice? * Is the time taken to fit a contact lens is reduced compared to standard practice? * Is there user acceptance of the new lens? * Are the Axial ege lift (AEL) changes clinically significant? There will be 3 work packages WP1: For each participant data collection will take place over two visits. • Visit 1: Pentacam topography scans and optimal 'virtual' lens selection will take place. • • Visit 2: Participants are fitted with 4 contact lenses (i) the optimal lens design as specified by the virtual fitting module, (ii) a contact lens with a clinically significant step flatter AEL (iii) a contact lens steeper in axial edge lift (AEL) (iv) the participant's own contact lens. Each CL fit will be assessed with slit lamp photography according to the standardised method proposed by Wolffsohn et al. (2013), Anterior segment OCT MS39) (CSO Hansom Instruments, UK) and best-corrected visual acuity with each lens design using high-contrast logMAR . WP2. Participants will attend one appointment where a traditional lens fit, and a lens fitted using the topography guided 'virtual' module will be undertaken (with the fitting method selected for each eye randomised). For each fitting method the total fitting time will be measured and the total number of trial contact lenses used. Patients will be invited to complete a questionnaire that probes their satisfaction of this process. WP3. Clinicians not involved in the study will be invited to examine a demo version of the virtual fitting module and complete the validated system usability scale tool.
NCT03442751
To evaluate the safety and efficacy of epithelium-on corneal collagen cross-linking (CXL) in impeding the progression of, and/or reducing corneal curvature (Kmax) in eyes with progressive keratoconus. Epithelium-on CXL uses a formulation that allows the riboflavin to penetrate the cornea without the need to remove the epithelium, the outer most layer of the cornea.
NCT04168112
There is no standard of care medication regimen for the management of pain and inflammation post-corneal crosslinking (CXL), although most cornea specialists agree on use of an antibiotic and steroid eye drop in the immediate postoperative period. However, steroid tapering schedule and use of additional topical non-steroidal anti-inflammatory (NSAID) eyedrops vary amongst practitioners. The goal of this study is to compare postoperative pain scores between patients receiving a tapering dose of topical steroids over 1-month post-CXL, versus those receiving an intracanalicular dexamethasone insert.
NCT04668924
The purpose of this study is to evaluate the efficacy, safety and postoperative ocular discomfort by individually customized Photorefractive intrastromal crosslinking (PiXL) without epithelium debridement in high oxygen environment (Epi-on) for progressive Keratoconus.
NCT03990506
The purpose of this study is to evaluate the efficacy, safety and postoperative ocular discomfort by comparing individually customized Photorefractive intrastromal crosslinking (PiXL) for progressive Keratoconus. The study compares two different protocols, PiXL with corneal epithelium debridement (Epi-off) and PiXL without epithelium debridement in high oxygen environment (Epi-on), with the hypothesis that Epi-on gives less postoperative ocular discomfort.
NCT01789333
The purpose of the study is to see if brighter lights will allow for shortening of the treatment time required to stabilize the eyes of patients with keratoconus or a bulging cornea. The investigators will be comparing the therapeutic effects of two different higher brightnesses of ultra violet light on a riboflavin treated eye. One light will be twice as bright as the other and the exposure time of these brighter lights to deliver equivalent energy to the cornea will be reduced from the standard 30 minutes to 10 and 5 minutes. Riboflavin is vitamin B2 and the investigators are trying to determine if an identical clinical effect can be achieved the brighter treatment lights are used for shorter times. The investigators will also monitor the clinical effect and the status of the cornea to see if additional risks are associated with the brighter light.
NCT01112072
This study will determine the efficacy of corneal collagen crosslinking (CXL) combined with Intacs for the treatment of keratoconus and corneal ectasia. The goal of CXL is to decrease the progression of keratoconus, while Intacs has been shown to decrease corneal steepness in keratoconus. This study will attempt to determine the relative efficacy of the two procedures either performed at the same session versus CXL performed 3 months after Intacs.