View clinical trials related to Choroidal Neovascularization.
Filter by:This study will try to identify and treat feeder vessels in age-related macular degeneration. The macula is the part of the retina in the back of the eye that determines central or best vision. In macular degeneration, leaking blood vessels under the macula lead to loss of central vision. These vessels branch out tree-like from one or more feeder vessels. Instead of treating all the abnormal branching vessels, this study will try to find and close only the feeder vessels, thereby depriving the abnormal vessels of nutrition. The vessels will be closed with laser beam treatment. People 50 years of age and older with macular degeneration and visual acuity worse than 20/50 in the study eye and the same or better vision in the other eye may be eligible for this study. Candidates will undergo fluorescein angiography to try to locate feeder vessels. For this procedure, a yellow dye is injected into an arm vein. The dye travels to the blood vessels in the eyes, and 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. Before laser treatment, participants will have a complete eye examination, including measurement of visual acuity, evaluation of the front part of the eye with a slit lamp microscope, examination of the retina with an ophthalmoscope, and measurement of eye pressure using a tonometer. During the laser treatment phase of the study, participants will have indocyanine green angiography-a procedure similar to fluorescein angiography, but using a green dye-to photograph the retina and identify feeder vessels. If feeder vessels are located, laser beam treatment will begin. For this procedure, the eye is anesthetized with numbing drops. A special contact lens is then placed on the eye for the laser treatment. The number of treatments depends on how well the individual patient responds, but usually between two and eight treatments are required. The indocyanine green angiogram will be repeated after the laser beam treatment to determine if the feeder vessels have been successfully closed. If the vessels remain partially open, a repeat application will be done, followed by another indocyanine green angiogram to check the results. Patients will be checked in the clinic after 1 week to see if additional treatment is needed. If so, re-treatment will be done in a week. If no re-treatment is required, follow-up visits will be scheduled 2, 3, and 6 weeks after treatment, 3 and 6 months after treatment, and every 6 months after that for 2 years to evaluate treatment results. The evaluations will include fluorescein angiograms and other examinations that were done before starting treatment. If abnormal vessels are still present or growing, repeat treatments will be applied following the same procedure.
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.
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.