View clinical trials related to Macular Degeneration.
Filter by:This study will test the safety and effectiveness of a fluocinolone implant to treat age-related macular degeneration. This eye disease can severely impair central vision, affecting a person's ability to read, drive, and carry out daily activities. It is the leading cause of vision loss in people over age 60. The fluocinolone implant is a tiny plastic rod with a pellet of the steroid fluocinolone on the end. The pellet slowly dissolves and releases the medication into the fluid in the eye. Vision loss in macular degeneration is caused by the formation of new blood vessels in the choroid-a thin, pigmented vascular layer of the eye behind the retina. These abnormal vessels leak blood under the macula, the part of the retina that determines central vision. Tissue studies show evidence of inflammation in the retinas of patients. This study will test whether the slow release of the steroid fluocinolone directly into the affected part of the eye can prevent or slow further vision loss. Preliminary animal and human studies with fluocinolone implants have shown some benefit in reducing blood vessel growth and improving or stabilizing vision. Patients 50 years of age and older with age-related macular degeneration may be eligible for this study. Study patients will be randomly assigned to one of two treatment groups. One will receive a 0.5-mg dose implant; the other will receive a 2-mg dose implant. Theoretically, the implants can release the medicine for 2 to 3 years. Participants will have a medical history, physical examination and complete eye examination. The latter will include a vision test, eye pressure measurement, examination of the pupils, lens, retina, and eye movements. Photographs of the eye will be taken with a special camera. Patients will also undergo fluorescein angiography, a test that takes pictures of the retina using a yellow dye called sodium fluorescein. The dye is injected into the blood stream through a vein. After it reaches the blood vessels of the eye, photographs are taken of the retina. When the above tests are completed, patients will be scheduled for surgery to place the implant. The procedure will be done under either local or general anesthesia. Follow-up visits will be scheduled 1, 2, 4, and 6 weeks after surgery, then at 3 and 6 months after surgery, and then every 6 months until the implant is depleted of medicine or is removed. Several of the exams described above will be repeated during the follow-up period to evaluate the treatment and side effects, if any.
This study will examine whether taking the vitamin lutein changes lutein blood levels. Lutein, vitamin C, vitamin E and beta-carotene may be useful in treating the eye disease age-related macular degeneration, but more information is needed to support this. Age-related macular degeneration can significantly impair the ability to read, drive, and carry out daily activities. It is the most common cause of vision loss in people over age 60. Lutein a carotenoid that occurs naturally in the retina (the back part of the eye), especially the macula-the part of the retina that is important for fine, detailed vision. Men and women 60 years of age and older, with or without age-related macular degeneration, may be eligible for this study. Candidates will undergo the following tests: 1. Medical history and physical examination. 2. Eye examination-Includes evaluation of visual acuity, measurement of eye pressure, examination of the lens, retina, pupils and eye movements, and photographs of the eye. 3. Visual field study-Examines the ability to see objects in the periphery. The subject looks at a target on a screen and indicates when lights that appear in other places on the screen are visible. 4. Flicker photometry-The subject looks at a flashing light and turns a knob until the light stops flashing. 5. Blood tests-To measure blood levels of lutein and other carotenoids, liver function, cholesterol and triglycerides. Participants will be randomly assigned to take one of three dosages of lutein (2.5 milligrams, 5 milligrams or 10 milligrams) for 6 months and will be examined at follow-up visits scheduled 1, 3, 6, 9 and 12 months after starting lutein. During these visits, many of the exams described above will be repeated to evaluate the effects of lutein treatment on the eye.
This screening protocol is designed to help recruit patients for National Eye Institute (NEI) studies of the retina, such as diabetic retinopathy and macular degeneration. Patients must meet the specific criteria of a research study, and this protocol serves as a first step for admitting patients to a retinal disease study. Candidates will undergo a medical history and comprehensive eye examination. The eye examination includes dilation of the pupils to fully examine the retina. In some studies, photographs of the eye are required. This is done using fluorescein angiography. In this procedure, a dye called sodium fluorescein is injected into the blood stream through a vein. After the dye reaches the blood vessels of the eye, photographs are taken of the retina. Other diagnostic procedures may include physical examination, questionnaires, routine laboratory tests and other standard or specialized tests, as needed. When the screening is completed, patients will be informed of their options to participate in a study. Patients who are ineligible for a current study will be informed of alternative treatments or options. No treatment is offered under this protocol.
Age-related macular degeneration (AMD) represents the most common cause of blindness in patients over the age of 60. The major cause of vision loss in this disease is due to the development of choroidal neovascular membrane formation (CNVM). Several clinical trials have proven that eyes with "well-defined" CNVM or lesions that can be readily demarcated with fluorescein angiography can be successfully treated with laser photocoagulation. However, up to 87% of eyes present with "ill-defined" CNVM or lesions that cannot be well demarcated on fluorescein angiography and are not amenable to laser photocoagulation. No beneficial treatment for this form of choroidal neovascularization has been established. Histopathologic study has demonstrated the presence of inflammatory and reparative responses in the retina of patients with ill-defined choroidal neovascularization. Since corticosteroids have been shown to downregulate many of the cellular factors involved in both inflammation and repair, the present study is designed to assess the ability of corticosteroid injection around the eye to prevent severe vision loss associated with "ill-defined" choroidal neovascularization in the setting of age-related macular degeneration. The study will be organized as a randomized open label control clinical trial involving 2 phases. Phase 1 involving 40 patients will establish the feasibility and safety of this treatment modality. Phase 2 will place emphasis on efficacy of the study.
The efficacy of laser photocoagulation treatment for diabetic retinopathy has been demonstrated by several National Eye Institute (NEI) sponsored clinical trials. The Diabetic Retinopathy Study (DRS) demonstrated that scatter photocoagulation reduces the risk of blindness from diabetic retinopathy. The Early Treatment Diabetic Retinopathy Study (ETDRS) extended these findings by providing information on when to initiate scatter photocoagulation and by demonstrating that focal treatment was effective in treating macula edema. The Krypton Argon Regression Neovascularization Study (KARNS) showed that scatter photocoagulation with krypton red laser was just as safe and effective as the argon blue-green laser in the treatment of proliferative diabetic retinopathy. Unfortunately, there is little data on the long term effects of photocoagulation on visual function. The first objective of this study is to assess the long term effects of photocoagulation for diabetic retinopathy. A second objective is to provide additional information on the risk of progression of cataracts in persons with diabetes. All patients previously treated with laser photocoagulation (focal and/or scatter) are eligible to participate in this long term study. The first priority will be given to patients who participated in the ETDRS and KARNS because of the wealth of information available regarding the details of their treatment and course after treatment. Study evaluations will include a standard ophthalmic examination, fluorescein angiography, lens and fundus photography.
The purpose of this study is to evaluate possible mechanisms of central visual loss in patients with diabetes mellitus. The visual loss of interest to be investigated is that associated with macular edema (prior to and following laser photocoagulation treatment) and that associated with panretinal photocoagulation. The evaluation will be performed with psychophysical testing, i.e., static perimetry and contrast sensitivity function. Of particular interest, the mechanisms of visual loss associated with macular edema (prior to and following laser photocoagulation) will be further investigated. Photoreceptor-mediated visual loss will be assessed by measurements of the Stiles-Crawford effect. Visual loss mediated by post-receptoral retinal changes will be assessed by measuring the Westheimer spatial desensitization/sensitization effect.
Clouding of the lens, or cataract formation, accounts for vision loss in about 45 percent of the U.S. population aged 75 to 85 years. Macular degeneration-destruction of the part of the retina responsible for central vision used in reading-is the leading cause of legal blindness in people over 60 years of age. This 10-year study on age-related macular degeneration and cataract will investigate: 1. The natural course and prognosis of these diseases; 2. The effects of vitamin and mineral supplements on their development and progression; and 3. Risk factors associated with their development. Patients with age-related macular degeneration or cataract will be evaluated for their eligibility in this study with a medical history, vision test and thorough eye examination, including photographs of the lens and back of the eye. Those accepted to the study will be randomly assigned to take one of the following 4 times a day: 1) a vitamin only; 2) a mineral only; 3) both a vitamin and a mineral; or 4) a placebo (a tablet with no active ingredient). A blood sample will be drawn at the beginning of the study and once a year until its end to measure vitamin and mineral blood levels and to study their effects on cholesterol. Participants will be asked to complete a voluntary questionnaire about their visual function and how it affects their daily lives. Some patients may be asked to participate in two interviews about 6 months apart, in which they will provide information on their food intake over a 24-hour period. This information will be used to explore possible dietary risk factors for macular degeneration and cataract. Participants may also be asked to provide a small blood sample for use in studying possible hereditary factors associated with age-related macular degeneration. This research may lead to a better understanding of why the condition develops, who is likely to be affected and to what degree, and how to improve treatment.
The purpose of this project is to diagnose and evaluate ocular and related tissues with various diseases such as conjunctival, corneal, uveal, vitreoretinal and optic nerve disorders, ocular degenerative, metabolic or genetic diseases and tumors. These will be studied using light microscopy, electron microscopy, confocal microscopy, immunohistochemistry, molecular pathological including polymerase chain reaction and in situ hybridization, as well as measuring the functions of cellular organelles, e.g., mitochondrial function. Lymphocytes in the peripheral blood as well as other involved biopsied tissues and ocular tissue will be compared and categorized by disease. Cytokines, chemokines or growth factors and/or other released molecules in the blood and ocular fluids will be also analyzed. Elucidating the relationship between the infiltrating cells, ocular resident cells, and their products in various diseases will help us to make diagnoses and increase our understanding of human ocular disorders. Patients who require eye surgery to treat an eye disease or other disease in which the eye is involved may participate in this study. Samples of eye tissue and fluid that are normally removed and discarded during eye surgery will instead be given to researchers for study. The tissues will be examined under microscope and studied using sophisticated chemical and biological tests. Immune cells from blood samples may also be examined. These studies will help better understand and diagnose the various eye diseases and to develop more attractive therapies.
To determine whether application of low-intensity laser treatment of eyes with drusen in the macula can prevent later complications of age-related macular degeneration and thereby preserve visual function.
To determine whether scatter argon laser photocoagulation can prevent the development of neovascularization. To determine whether peripheral scatter argon laser photocoagulation can prevent vitreous hemorrhage. To determine whether macular argon laser photocoagulation can improve visual acuity in eyes with macular edema reducing vision to 20/40 or worse.