Active clinical trials for "Corneal Diseases"

Using collagenase to isolate limbal stem cells and improve the technique of ex vivo expansion of limbal stem cells for the treatment of patients suffering from unilateral limbal stem cell insufficiency based on the concept of "limbal stem cells need special cell-cell contact and cell-extracellular matrix interaction to support their survival".

The purpose of this research is to determine if a new investigational contact lens shape allows the eye to get more oxygen.

The purpose of this study is the investigation of biomechanical properties of the cornea using computer-aided data analysis. Currently, it is known that keratoconus and glaucoma are ocular disease that are associated with biomechanical alterations of the cornea. 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. In glaucoma, the information about corneal alterations serves in two ways, first, correct measurement of intra ocular pressure (IOP); second, early diagnosis of suspects before visual field defects are detectable. Especially, the Corvis ST is an air-puff tonometer that measures intraocular pressure, corneal thickness (CCT) as well as dynamic corneal response (DCR) parameters. Most of the DCR parameters are affected by IOP and CCT: Therefore, algorithm are needed to determine parameters without impact of IOP and CCT that are describe the biomechanical properties of the cornea.

The objective of this study is to evaluate the ease of use of a modified, disposable contact lens and suction ring assembly.

Brittle Cornea Syndrome and Ehlers-Danlos Syndrome (EDS) type VI are rare collagen-connective tissue disorders that predispose affected individuals to the development of perforated corneas from the mildest of eye trauma or even spontaneously. Clinical studies evaluating riboflavin-corneal crosslinking have found that it dramatically increases corneal rigidity. Given the success and safety of riboflavin crosslinking, the investigators believe that it can increase the corneal stability in patients affected these disseases, preventing perforation. It is furthermore possible, that riboflavin crosslinking will allow corneal transplants to successfully be performed on blind eyes that have already perforated and opacified. The purpose of the study is to determine whether corneal crosslinking can be safely performed on individuals with Brittle Cornea Syndrome or Ehlers-Danlos Syndrome type VI.

The aim is to find out more about how corneal sensory fibres react to different types of stimuli (liquid / tactile / nylon thread) and how this can be consciously perceived by the individual. Is it possible to generate a stimulus that delivers a repeatable and reliable response within a useful stimulus force range which allows an interpretation / evaluation of normal / expected activity of superficial nerve fibres in the cornea? The study group will be divided into three groups of individuals: two groups with different types of contact lenses (CL) and one without CL, as sensitivity changes are thought to occur with CL wear. A very interesting research question is to find out, if such sensitivity differences can be detected with the nature of the stimuli applied in this study.

Keratoconus is a progressive corneal disease characterized by asymmetric corneal thinning and structural changes in corneal collagen which leads to decrease in visual acuity due to myopic shift, irregular astigmatism or corneal scarring. Early detection of the disease in children aids in halting the progression and improve their quality of life. There is no consensus regarding the progression criteria of the disease, we aimed to assess the changes in corneal asphericity in children after corneal collagen crosslinking and investigate any possible correlation with progression criteria widely used.

The primary objective of this clinical study is to compare the Nidek RS-3000 Optical Coherence Tomography (OCT) device to the Optovue RTVue OCT. The secondary objective is to evaluate any adverse events found during the clinical study.

This study will explore the clinical and hereditary (genetic) features of corneal dystrophy and other inherited corneal disease. Corneal dystrophy is clouding of the cornea - the transparent part of the eye covering the iris and pupil that passes light to the back of the eye. When the cornea becomes cloudy, interfering with the passage of light, vision may be impaired or lost. Corneal problems may occur with vision problems alone, or with other problems, such as changes in facial appearance or bone or joint problems. A better understanding of these genetic conditions may help in the development of better diagnostic tests and methods of disease management. Patients with corneal dystrophies and related corneal disease and their family members may be eligible for this study. Participants will be drawn from patients enrolled in other studies of corneal dystrophy at the NEI and collaborating clinics. Participants will undergo the following tests and procedures: Medical and surgical history Verification of diagnosis Construction of a family tree regarding familial vision problems Complete eye examination, including dilation of the pupils and photography of the cornea, tests of color vision, field of vision, and the ability to see in the dark, and photographs of the eye. Blood sample collection to identify the genes responsible for corneal disease and ascertain how they cause disease.

By comparing the preoperative data and postoperative data of 9 patients of microspherophakia, we concluded that the 6-point transscleral suture fixation of a 3-looped haptics posterior chamber intraocular lens (PC-IOL) through scleral pockets was a feasible method of PC-IOL implantation in the surgical treatment of microspherophakia.