View clinical trials related to Retinitis.
Filter by:This study will evaluate the role of certain gene variants on the onset and course of cytomegalovirus (CMV) retinitis-a severe infection affecting the eye-in patients with AIDS. Symptoms include blurry vision, eye pain, photophobia, floaters, eye redness, and impaired vision. Left untreated, it can cause blindness. The study is done in collaboration with investigators of the Longitudinal Studies of the Ocular Complications of AIDS (LSOCA) at the Johns Hopkins University School of Medicine. The purpose of the LSOCA study is to learn about how HIV and other infections associated with AIDS and their treatments affect people's eyes and sight. Blood samples previously collected from patients participating in the LSOCA study will be analyzed for gene variants. These differences will then be correlated with the patients' clinical data to try to discover the role of gene differences among patients on the following: susceptibility to CMV and related problems; development and course of CMV; and response to HAART (highly active antiretroviral treatment), particularly in CMV onset and pathology. The study will use blood samples and clinical information previously collected from patients during their participation in LSOCA. The materials will be identified with a numerical code linking the samples and clinical data. No additional procedures will be performed on patients for this study.
The objective of this study is to evaluate the safety and efficacy of the retinal stimulation system by evaluating the data after chronic implantation.
The purpose of this study is to determine whether the structure and function of the human retina can be studied with high resolution in patients with inherited retinal degenerations using the Adaptive Optics Scanning Laser Ophthalmoscope (AOSLO).
This multinational study will investigate the inheritance of genetic retinal degeneration in families of different nationalities and ethnic backgrounds in order to identify the genes that, when altered, cause retinal degeneration. The retina is a light-sensitive membrane lining the back part of the eye. It relays vision signals to the brain, which the brain interprets into sight. When the retina degenerates, vision is altered and possibly lost. The findings of this study should help improve diagnosis and methods of treatment for these disorders. Participating institutions include: the National Institutes for Health in Bethesda, Maryland; the University of Miami in Florida; the Casey Eye Institute in Portland, Oregon; the Byrd Health Sciences Center in Morgantown, West Virginia; the University of Texas Southwestern Medical School in Dallas, Texas; the University of Tennessee Health Sciences Center in Memphis; the Prasad Eye Institute in Hyderabad, India; National Center of Excellence in Molecular Biology in Lahore, Pakistan; and the Jules Gonin Hospital in Lausanne, Switzerland. Patients with retinitis pigmentosa and closely related diseases such as Usher syndrome, snowflake vitreoretinal dystrophy and Bietti crystalline dystrophy may be eligible for this study. Participants undergo the following tests and procedures: - Medical and surgical history, including family history of vision problems. - Examination to clarify the type of retinal degeneration. - Eye examination, including tests of color vision, field of vision and ability to see in the dark - Electroretinogram to test the function of visual cells. For this test, the patient sits in a dark room for 30 minutes with his or her eyes patched. Then, a small electrode (silver disk) is taped to the forehead and the eye patches are removed. The surface the eyes is numbed with eye drops, and contact lenses are placed on the eyes. The patient looks inside a large dark globe that emits a series of light flashes. Then a light is turned on inside the globe and more lights flash. The contact lenses sense small electrical signals generated by the retina when the light flashes. - Hearing tests for patients with a personal or family history of deafness. Tests include an audiogram, ear examination and test of middle ear function. For middle ear function testing, the patient feels a little air pressure change for a moment and hears some tones. Another test requires the patient to sit quietly with electrodes on the head, forehead and earlobes. - Balance testing, including walking in a straight line, standing with eyes closed in the dark and other tests of coordination, and caloric testing. For the caloric testing, any ear wax in the ear canal is removed before the test begins. Then, electrodes are placed on the skin near the eyes and on the forehead. A small amount of cool (sometimes cold) or warm water is instilled into each ear canal, first one and then the other. - Blood sample collection for genetic testing.
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.
Purpose: Retinitis pigmentosa (RP) is characterized by progressive loss of visual function due to specific genetic mutations. This trial is focused on patients with one of the most severe forms of the disease, X-linked inherited RP (XLRP). This disease is characterized by early onset (typically loss of night vision as a child) followed by loss of peripheral vision as a teenager and young adult. There is no male-to-male transmission of the disease in the family. There is no cure for RP and treatment options are limited. Two clinical trials have not found a benefit from nutritional supplementation with the long-chain polyunsaturated fatty acid, docosahexaenoic acid (DHA), at low daily doses although there is evidence that it slows disease progression in certain instances. In this clinical trial, we propose that a high dose nutritional DHA supplement will slow the loss of visual function and preserve usable vision in patients with XLRP. This study is a 4-year placebo-controlled randomized clinical trial meaning that patients have a 50-50 chance of receiving placebo or experimental treatment. A total of 66 patients will be enrolled; 33 will receive placebo and 33 will receive the treatment. Entry criteria include diagnosis of XLRP by an ophthalmologist, age 7 to 32 years, male, sufficient visual function such that disease progression can be followed for the entire duration of the trial, and a willingness to visit the testing site (Dallas, TX) once a year. Annual visual function testing includes ETDRS visual acuity, full-field and multifocal electroretinography (ERG), static peripheral visual fields, and fundus photography. Cone ERG function is the primary outcome measure. Funding Source - FDA, Foundation Fighting Blindness, DSM Nutritionals
Some patients with HIV/AIDS suffer from a dangerous viral infection of the retina (and other organs) called cytomegalovirus infection (CMV). The medications currently used to treat CMV all have serious side effects. AIDS patients are prone to this infection because their immune system produces a lower number of CD4+T lymphocytes, the type of blood cells that fight viral infections. Some new HIV medications strengthen the immune system. This study will investigate the possibility that CMV patients on these HIV medications can develop immune systems strong enough to fight CMV without CMV medication. The study will enroll a maximum of 15 adult HIV/AIDS patients who have a CD4+T cell count over 150 cells/microliter and who have inactive CMV retinitis that is not immediately sight threatening. It is expected to last approximately 2 years. Each prospective participant will have a physical examination and complete eye examination, including retina photographs, with the eye examination and retina photographs repeated 2 weeks later. If there is no evidence of active CMV retinitis, the participant will be enrolled in the study, and CMV medication will be stopped. The participant will have physical and eye examinations every 2 weeks for the first 3 months of the study, and every 3 weeks for the next 3 months. After 6 months, the frequency of the examinations will be 2-8 weeks, depending on the participant's CD4 count. After one year, a participant with a CD4 count remaining over 150 cells/microliter may return to the care of a local ophthalmologist with HIV/CMV experience, revisiting the clinical center every 6 months. The participant's CMV medication will be restarted when CMV retinitis becomes active, which will terminate participation in the study.
Retinitis pigmentosa (RP) is a collective term for a group of inherited retinal dystrophies that are a major cause of irreversible blindness. RP of some type occurs in approximately 1 out of 3500 persons in the United States(1). Gene mutations are responsible for the majority of RP. To date, mutations have been identified in 30 different genes linked to RP(2). The visual prognosis of RP is poor, since the gradual but relentless visual field loss leads eventually to some degree of blindness(3). Although no effective treatment for RP has been identified, participants supplemented with a daily oral dose of 15,000 IU vitamin A palmitate have shown, on average, a slower rate of deterioration of retinal function when the intervention is continued over several years(4). The purpose of this research is to determine whether administration of high oral doses of vitamin A can acutely improve cone photoreceptor function in RP participants as measured by electroretinography (ERG). In this interventional, non-randomized, prospective, pilot study, 5 participants will receive a daily oral dose of 50,000 IU of vitamin A palmitate for 4 weeks, followed by a maintenance dose of 15,000 IU daily for the subsequent 2 weeks. The primary efficacy outcome is a relative percentage change in ERG response amplitude subsequent to vitamin A supplementation. A secondary efficacy outcome is a relative percentage change in implicit time from pre- to post- vitamin A supplementation, with improvement specified as a shorter response implicit time. Other secondary outcomes will be improvements in visual field (Humphery, 10-2; sum of thresholds). Safety outcomes include visual fields, ETDRS visual acuity, intraocular pressure, serum vitamin A level and liver function tests.
This study will evaluate the safety of a ciliary neurotrophic factor (CNTF) implant placed in the eye to allow the release of CNTF directly on the retina. The results of this study may lead to a larger investigation of CNTF implants to treat retinitis pigmentosa (RP), a progressive degenerative eye disease that begins with loss of peripheral vision and night blindness and often leads to blindness in later life. Currently, there are no effective treatments for RP. Researchers have found, however, that certain proteins, called ciliary neurotrophic factor (CNTF), can partially protect cells in the eye if given directly inside the eye. A major challenge in treating RP is to deliver medicine directly into the eye. One way to ensure that CNTF gets into the eye is to surgically place an implant inside the eye to release the protein. Patients 18 years of age and older with retinitis pigmentosa whose visual acuity is 20/100 or worse may be eligible for this study. Candidates will be screened with a medical history, physical examination, eye examinations, and eye photographs. The eye examination includes measurement of visual acuity and eye pressure, examination of the pupils and eye movements, and examination of the lens and back of the eye. In addition, patients will have the following tests: - Visual field test: Patients look at a central spot on a white screen and tell the examiner whenever they see a small light appear at other places on the screen. - Electroretinogram (ERG): Electrodes are taped to the patient's forehead. Special contact lenses are placed on the eyes, similar to normal contact lenses, after the eye has been numbed with drops. The contact lenses sense small electrical signals generated by the retina. The ERG measures the electrical activity of the retina when it is stimulated by light. For the ERG recording, the patient looks inside a large, hollow, dark sphere, and sees flashes of light, first in the dark, and then with a light turned on in the sphere. - Optical coherence tomography: This test, done with the machine used to examine the eye, measures retinal thickness by producing cross-sectional pictures of the retina. Participants undergo surgery at the NIH Clinical Center in a 30-minute operation to place the implant in one eye. The surgery is done under local anesthetic. Before the procedure, patients are given a steroid injection along side the eye to minimize inflammation after surgery. Following the procedure, patients return for follow-up visits once a month for 6 months. At these visits, several of the exams described above are repeated to evaluate treatment effects and check for adverse side effects. After 6 months, the implant is surgically removed. Post-surgical care for both implant and explant surgeries include examinations the day and week after surgery to examine the wound, a high dose of steroid immediately after surgery, oral antibiotics for 7 days, and eye drops for 1 week to prevent infection and inflammation.
Phase I/II double-masked, randomized, placebo-controlled, cross-over trial to determine effects of lutein on vision in retinitis pigmentosa, including safety and effective dosage assessment