View clinical trials related to Keratoconus.
Filter by:Patients with KCN who undergo cornea transplantation divided to 2 groups: Group1: After mechanical trephination, horizontal meridian of donor's cornea sutured to horizontal meridian of recipient cornea Group 2: After mechanical trephination, horizontal meridian of donor's cornea sutured to vertical meridian of recipient cornea After suture removal, best corrected visual acuity, refractive error, corneal keratometry, irregularity of corneal surface and high order aberration of two groups will compare
Knowledge of the pathogenesis of ocular conditions, a leading cause of blindness, has benefited greatly from recent advances in ophthalmic imaging. However, current clinical imaging systems are limited in resolution, speed, or access to certain structures of the eye. The use of a high-resolution imaging system improves the resolution of ophthalmoscopes by several orders of magnitude, allowing the visualization of many microstructures of the eye: photoreceptors, vessels, nerve bundles in the retina, cells and nerves in the cornea. The use of a high-speed acquisition imaging system makes it possible to detect functional measurements such as the speed of blood flow. The combination of data from multiple imaging systems to obtain multimodal information is of great importance for improving the understanding of structural changes in the eye during a disease. The purpose of this project is to observe structures that are not detectable with routinely used systems.
To evaluate the safety and effectiveness of the PXL Platinum 330 system for performing corneal cross-linking (CXL) for the treatment of ectatic disorders.
To assess depth of demarcation line in transepithelial versus epithelium-off accelerated cross-linking in keratoconus patients
Aim of this study is to conduct longitudinal and cross-sectional analyses about the corneal ectatic disease Keratoconus based on data obtained from Keratoconus patients in the Homburg Keratoconus Center (HKC). The Homburg Keratoconus Center (HKC) was founded in 2010 and, up to now, comprises more than 2.000 Keratoconus patients. Topographic, tomographic and biomechanic characteristics of the disease are being analyzed with the intention to elucidate how the disease begins and develops during lifetime.
The study objective is to compare accelerated and standard corneal crosslinking for treatment of progressive keratoconus or corneal ectasia.
To determine whether the Peschke PXL-330 system is safe and effective in the treatment of corneal thinning conditions.
Aim of work: - To detect abnormal corneal thinning in keratoconus using pachymetry maps measured by high-speed anterior segment optical coherence tomography (OCT). - To evaluate the visualization and depth of the demarcation line with anterior segment optical coherence tomography (AS-OCT) after corneal collagen cross-linking (CXL). - To compare the depth of demarcation line between epithelial-on (Epi-on) and epithelial-off (Epi-off) corneal collagen cross-linking.
Background: The objective of corneal collagen crosslinking (CXL) is to increase the binding of intrafibrillary and interfibrillary covalent bonds to improve the mechanical stability of the cornea and thus to stop the progression of corneal ectasias. Although the vast majority of studies have described pain after photorefractive keratectomy (PRK), the pathophysiological principle of pain is similar in CXL. From the anatomical point of view, the corneal epithelium is the most densely innervated and sensitive surface of the body, being 300-600 times greater than in the skin. The pain after CXL comes from several routes, the process begins with the epithelial rupture that generates exposure of the nerve endings, induces apoptosis and necrosis of the epithelial cells. Subsequently an inflammatory cascade is initiated in which the different cytokines stimulate the nerve terminals. Inflammatory mediators also activate the ion channels in the nerve membrane, and this process continues until the epithelium heals. Additionally, exposure to UVA rays can also cause nerve damage. The effect of local cold for pain management has already been reported in PRK. By cooling the cornea, the release of chemical mediators and inflammation can be reduced. In the CXL radiation is transformed into several forms of energy: fluorescent radiation, chemical energy and, to a small extent, heat. The CXL process is energetically comparable to photosynthesis, in which the radiation energy is transformed into chemical energy (glucose) with the help of pigments (chlorophyll). The thermal effect is negligible in the photochemical method of CXL. Justification: No method for the control of pain after crosslinking is considered ideal or universally accepted, the importance of this study lies in looking for an additional tool to reduce the most common postoperative complaint in a highly performed procedure worldwide. Hypothesis: The application of riboflavin at 4oC reduces the pain assessment after the CXL. Purpose: to evaluate the effect of the application of riboflavin at 4oC in the assessment of postoperative pain in patients undergoing CXL. Materials and methods: Prospective and interventional clinical study in patients older than 18 years with a diagnosis of keratoconus who underwent CXL, in the cornea and refractive surgery service of the Ophthalmology institute Fundación Conde de Valenciana.
Optical Coherence Tomography (OCT) devices are non-contact instruments that can measure the depth of scars, other causes of cloudiness of the cornea, and degree of corneal thinning in patients with keratoconus. Laser Custom Corneal Collagen Cross-linking (CXL) significantly decreases corneal aberrations and improves vision. This study will use OCT-guided setting for the lasers used in the corneal smoothing portion of the laser custom CXL procedure to assess the affect on visual outcomes.