Active clinical trials for "Retinitis"

The objective of this study is to develop the comprehensive visual function evaluation method in severe visually impaired patient.

Purpose: To study the associations between visual functions and the retinal tomography detected by optical coherence tomography (OCT) in patients with retinitis pigmentosa (RP). Study design: retrospective, non-randomized and non-comparable study Material: Medical recordings of the RP patients who visited the Out-Patient Department of Ophthalmology in NTUH during June, 2003 to June, 2008. Methods: By reviewing charts of the RP patients, the investigators will categorize RP patients into different types according to the loci of the pathological change in their retina evaluated by opththaomoscopy. And the investigators will collect the data of their visual functions including visual acuity, visual field, Arden ratio of electrooculography, and color sense discrimination. Then, according to the OCT map, the investigators will analyze the retinal thickness by dividing the macular area into foveal area, inner ring and outer ring. Finally, the investigators will analyze the relationships between visual functions and retinal thickness in different macular areas in different types of RP patients. Anticipated results: The investigators expect that retinal tomographies may different among different types of RP. And the retinal tomographic change may correspond to the change of a certain kind of visual function. Hence, according to the thickness of a specific area in macula, the investigators may anticipate that some visual dysfunction may exist.

The purpose of this study is to understand how changes in the immune system of HIV-infected patients affect their risk for 3 serious infections: Pneumocystis carinii pneumonia (PCP), cytomegalovirus (CMV) retinitis, or CMV organ disease. The purpose also is to understand how anti-HIV medicines may improve the immune system in these patients. (This purpose reflects a change in the AIDS-related [opportunistic] infections studied.) Presently, HIV-infected patients who have had PCP or CMV disease stay on lifelong therapy to prevent the return of the disease. This study is trying to see if a special lab test can help identify which patients can stop this preventive therapy without having another episode of PCP or CMV organ disease. (This rationale reflects a change in the AIDS-related infections studied.)

This study is aimed to characterize Russian population of Usher patients.

A new fundus-guided microperimeter (MP-3S) has been developed by Nidek, Inc. to track the fundus of the patient and present stimuli in specific anatomically-defined locations. Furthermore, this tracking means that exactly the same locations can be tested on subsequent (follow-up) visits. The investigators will use a method called two-color perimetry to map rod and cone sensitivity on this device. With this technique, the sensitivity difference (blue-red) to chromatic test stimuli can be used to determine whether rods, cones or both photoreceptor systems mediate the threshold at a given location in the macula.

To evaluate the natural history of visual function in subjects with IRD phenotypically diagnosed as Leber congenital amaurosis (LCA) or retinitis pigmentosa (RP) caused by RPE65 or LRAT gene mutations.

This study will explore clinical and genetic aspects of Usher syndrome, an inherited disease causing deafness or impaired hearing, visual problems, and, in some cases, unsteadiness or balance problems. Patients with type 1 Usher syndrome usually are deaf from birth and have speech and balance problems. Patients with type 2 disease generally are hearing impaired but have no balance problems. Patients with type 3 disease have progressive hearing loss and balance problems. All patients develop retinitis pigmentosa, an eye disease that causes poor night vision and eventually, blindness. Patients of any age with Usher syndrome may be eligible for this study. Patients who have had eye and hearing evaluations are asked to send their medical records to the research team at the National Eye Institute (NEI) for review. They are also asked to have a blood sample drawn by a medical professional and sent to NEI for genetic analysis. Finally, they are interviewed about their family histories, particularly about other relative with eye disease. Patients who have not been evaluated previously have the following tests and procedures at NIH: Family medical history, especially regarding eye disease. A family tree is drawn. Blood draw for genetic studies of Usher syndrome. Eye examination to assess visual acuity and eye pressure, and to examine pupils, lens, retina, and eye movements. Electroretinogram (ERG) to test the function of visual cells. Wearing eye patches, the patient sits in a dark room for 30 minutes. Electrodes are taped to the forehead and the eye patches are removed. The surface of the eye is numbed with eye drops and contact lenses are placed on the eyes. The patient looks inside a hollow, dark globe and sees a series of light flashes. Then a light is turned on inside the globe and more flashes appear. The contact lenses sense small electrical signals generated by the retina when the light flashes. Fluorescein angiography to evaluate the eye's blood vessels. A yellow dye is injected into an arm vein and travels to the blood vessels in the eyes. Pictures of the retina are taken using a camera that flashes a blue light into the eye. The pictures show if any dye has leaked from the vessels into the retina, indicating possible blood vessel abnormality. Hearing tests to help determine the patient's type of Usher syndrome. Tests to evaluate hearing include examination of both ears with an otoscope, evaluation of the middle ear and inner ear, and hearing tests using earphones that deliver tones and words the subject listens and responds to. Vestibular testing for balance function. Balance testing involves three procedures: Videonystagmography: This test records eye movements with little cameras. First the patient follows the movements of some small lights. Next, while wearing goggles, the patient lies on an exam table and turns to the right and left. Lastly, a soft stream of air is blown into the patient's ears four times, once in each ear with cool air and once in each ear with warm air. Rotary chair test: With electrodes placed on the forehead, the patient sits in a rotary chair in a dark room. Several red lights appear on the wall of the room and the patient follows the lights as they move back and forth. Then the chair turns at several speeds, all slower than a merry-go-round. Vestibular evoked potential: Electrodes are placed behind the patient's ear and at the base of the neck. Seated in a reclining chair and wearing earphones, the patient hears a brief series of loud clicking sounds. When the sounds are on, the patient is asked to lift his or her head up a few inches from the chair. The electrodes record information from the muscles in the neck as the sounds enter the ear.

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.

The Argus II Retinal Implant is a revolutionary new device, which offers vision to patients who are blind from retinal degeneration - retinitis pigmentosa. These patients have no alternatives. Patients typically can achieve ambulatory vision.

Using local immune suppression, the trial seeks evidence for the hypothesis that autoimmunity plays a role in the pathomechanism of retinitis pigmentosa.