View clinical trials related to Blindness.
Filter by:The project objective is to validate the types of eye trackers that may most effectively be employed in the rehabilitation evaluation and training of people with central scotomas. The eye trackers will include the three basic types of eye trackers, namely, 1)electrophysical, 2) front surface trackers, and 3) retinal trackers.
The project has four primary objectives: 1) Determine if blind rehabilitation improves the quality of life of legally blind veterans; 2) Determine the relationship between quality of life and visual function; 3) Determine if factors, such as cognitive status, level of depression, age and the presence of additional medical conditions besides vision loss, intervention of blind rehabilitation extends beyond the visually impaired individual and improve the quality of life of their primary caregiver (e.g. spouse, partner, family member or friend.)
The purpose of this study is to test the belief that specific areas of the brain are connected differently in blind patients than patients with sight. In addition, the study will examine the different anatomical connections between brain areas of patients who became blind early in life versus patients who became blind later.
The purpose of this study is to investigate the physiology associated with plasticity of the motor system. Plasticity refers to the process by which neighboring brain cells assume the responsibilities of damaged or diseased brain cells. The mechanisms behind this process are unknown. However, researchers have several theories about how plastic changes take place. Possible explanations include the growth of new connections between brain cells and the use of previously unused connections. Researchers plan to use transcranial magnetic stimulation and drug intervention in order to determine the mechanisms responsible for specific types of plasticity. Previous studies have shown that certain drugs can affect the mechanisms involved in these changes. By using one drug at a time, researchers plan to evaluate the role of each of several different mechanisms in brain reorganization.
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.
To determine whether photocoagulation helps prevent severe visual loss from proliferative diabetic retinopathy. To determine whether a difference exists in the efficacy and safety of argon versus xenon photocoagulation for proliferative diabetic retinopathy.
To evaluate the effectiveness of both argon laser photocoagulation and aspirin therapy in delaying or preventing progression of early diabetic retinopathy to more severe stages of visual loss and blindness. To help determine the best time to initiate photocoagulation treatment in diabetic retinopathy. To monitor closely the effects of diabetes mellitus and of photocoagulation on visual function. To produce natural history data that can be used to identify risk factors and test etiologic hypotheses in diabetic retinopathy.