National Eye Institute

The Age-Related Eye Disease Study (AREDS) was a randomized clinical trial study that followed participants over eight years since the start of enrollment in 1992 and was completed in 2001. The study showed the combination of high levels of antioxidants and zinc can reduce the risk of advanced Age-Related Macular Degeneration (AMD) and its associated vision loss. This combination isn't a cure or treatment for AMD. The specific daily amounts of antioxidants and zinc used in the study were: 500 milligrams of vitamin C, 400 International Units of vitamin E, 15 milligrams of beta-carotene (equivalent to 25,000 International Units of vitamin A), 80 milligrams of zinc as zinc oxide, and 2 milligrams of copper as cupric oxide.[6]

The Age-Related Eye Disease Study 2 (AREDS2) started in 2006 and was completed in 2012. AREDS2 is a second separate study from the original AREDS study. The purpose of this study was to improve and test different combinations of the original AREDS formula by adding omega-3 fatty acids, antioxidants lutein and zeaxanthin, removing beta-carotene, and lowering the amount of zinc. The antioxidants, lutein and zeaxanthin, were added to substitute beta-carotene from the formula because of the risk of lung cancer for smokers and former smokers found in a study conducted by the National Cancer Institute (NCI). Researchers added omega-3 fatty acids because of recent research found that it may be helpful to vision health and the zinc was lowered because some experts believed 80 mg was too high of a dosage.[7][8]

The Comparison of Age-Related Treatment Trial: Lucentis-Avastin (CATT) study was a two-year multicenter clinical trial that started in 2008 to compare the effectiveness of the two current treatments used for AMD. The results of the study concluded that both Lucentis and Avastin were equally effective in treating and improving vision, whether it was used monthly or on as needed basis.[9][10]

ETDRS Chart 1, used to measure visual acuity in the right eye

A multicenter, randomized clinical trial that treating clinically significant macular edema (CSME) with focal argon laser photocoagulation reduced the risk of additional vision loss; aspirin showed no benefit in delaying or reducing the onset or severity of retinopathy. Likewise, aspirin did not increase the risk for development of retinopathy or the progression of retinopathy. The participants were followed up to at least five years after they were enrolled in the study.[11][12]

Another significant contribution of the ETDRS was the introduction of the ETDRS charts, a set of three logMAR charts now widely used for the measurement of visual acuity in vision research and clinical practice.[13]

A network of NEI supported researchers, who are a part of the Diabetic Retinopathy Clinical Research Network completed a two years study in 2015 that found the drug Lucentis can be an effective treatment for people with advanced stage diabetic retinopathy, called proliferative diabetic retinopathy. Proliferative diabetic retinopathy is the growth of abnormal blood vessels that leak blood. This can distort vision and damage the retina. Lucentis is one of several drugs called vascular endothelial growth factor (VEGF) inhibitors that can block the growth of abnormal blood vessels. This is also commonly used to treat age-related macular degeneration. This study suggests that using VEGF inhibitors may help prevent macular edema.[14]

The Advanced Glaucoma Intervention Study (AGIS) is designed to provide a comprehensive assessment of the long-range outcomes of medical and surgical management in advanced glaucoma over a four-year period. The study uses visual function status to compare two intervention sequences in managing the disease.[15]

After seven years of follow-up on patients enrolled in the AGIS, results revealed that blacks and whites differed in the way they benefited from the two treatment programs. Based on the study results, it is recommended that black patients with advanced glaucoma begin a treatment program that starts with laser surgery, which is consistent with current medical practice. In contrast, white patients with advanced glaucoma who have no life-threatening health problems should begin a treatment program that starts with trabeculectomy. This recommendation is inconsistent with current medical practice.[16]

Because glaucoma is a lifelong disease, long-term information is important. The AGIS patients will continue to be followed for up to four more years.[16]

The Idiopathic Intracranial Hypertension (IIH) Treatment Trial enrolled participants in 2010-2012 and they were followed up for 6 months with the last follow-up in 2013. The study tested a glaucoma drug called acetazolamide (diamox) and weight loss plan to help improve vision for women who have idiopathic intracranial hypertension disorder. IIH is also called pseudotumor cerebri and usually affects overweight women. The most common symptoms associated with IIH are headaches and visual problems that include blind spots, poor side vision, double vision, and temporary episodes of blindness. The study results showed that a weight loss plan and acetazolamide can help preserve and restore vision for women with IIH.[17]

Retinopathy of prematurity (ROP) is an eye disease that affects premature infants. It is one of the most common causes of vision loss in childhood and can lead to vision impairment and blindness as children grow older. The Early Treatment of Retinopathy of Prematurity Study (ETROP) helped doctors predict which infants with ROP would benefit from early treatment by identifying certain eye characteristics. The early intervention would try to prevent severe vision loss later in life. Infants with ROP were treated using cryotherapy. Cryotherapy freezes the outer parts of the retina to slow down or stop the growth of new abnormal blood vessels.[18]

Amblyopia, also known as lazy eye, is the most common cause of vision impairment among children. Amblyopia occurs when one eye is weakened because the eye and brain are not working together. The standard treatment for amblyopia is patching: covering the stronger eye with a patch for two hours a day to improve vision in the weaker eye. However, a recent report by the Pediatric Eye Disease Investigators Group (PEDIG) suggested that extending the daily duration of patching from two to six hours a day is effective at treating persistent amblyopia. The research was funded by NEI.[19]

NEI researchers conducted a study that looked at the bacteria in the gut and how it protects the natural flora. Findings from studies suggest that this characteristic may be similar to how immune cells attack the eye in autoimmune eye diseases such as uveitis. Autoimmune uveitis is an inflammatory eye disease where the immune cells attack proteins in the eye. By studying how immune cells, also known as T cells, attack other parts of the body, researchers may gain further information on how the T cells are activated in the eye. It will also allow researchers to understand the disease better and develop treatments or therapies.[20]

Following the 2014 Ebola virus outbreak in Liberia, NEI investigators joined other researchers and investigators to be a part of the PREVAIL III (Partnership for Research on Ebola Virus in Liberia) study. Ebola survivors reported a variety of complaints such as headaches, joint and muscle pain, eye fatigue and blurry vision. Some reports indicate that survivors have uveitis. Uveitis is a group of inflammatory autoimmune eye disease that produces swelling and destroys eye tissue. This can reduce vision or lead to vision loss. It is unknown to researchers what the physical long term effects of survivors, including eye health.

In March 2015, investigators from different eye institutes including NEI, oversaw the design of an eye clinic for PREVAIL III in Liberia. The NEI team will travel back to Liberia during the course of the study to assist other health care professionals and partners to help provide follow-up eye care in the clinic for study participants. PREVAL III is sponsored by the National Institute of Allergy and Infectious Diseases of NIH.[21]

Retinitis pigmentosa (RP) is a group of rare, genetic disorders that involve a breakdown and loss of cells in the retina. Some of the most common symptoms of the disease are poor night vision and the loss of peripheral (side) vision. Currently there is no treatment to cure RP. A recent study by NEI-funded researchers showed that gene therapy can help preserve vision in late stage retinitis pigmentosa using canine models. Gene therapy halted the thinning of the retinal layer where photoreceptors are located and preserved the surviving photoreceptors. Research is still on going.[22]

NEI help fund the first retinal implant device called Argus II Retinal Prosthesis System, developed in 2011 by Second Sight Inc. to treat people who have retinitis pigmentosa. Argus II is a camera that is mounted on eyeglasses. The image is captured through the camera and processed by the video processing unit that transmits electrical pulse images to the retinal prosthesis through eyeglasses. This helps people with retinitis pigmentosa potentially move around and be independent. The NEI, Department of Energy, and the National Science Foundation (NSF) provided the support for the development of Argus II.[23]

Leber congenital amaurosis (LCA) is an inherited disorder that causes vision loss. NEI-funded scientists discovered that treating patients with gene therapy for Leber congenital amaurosis (LCA) may improve eyesight and sensitivity of the retina.[24] Some people with LCA have a mutated gene RPE65 that makes a protein found in the retinal pigment epithelium, which is a layer of cells that nourishes the light sensors or photoreceptors cells of the retina. LCA patients with this form of the disease were injected with an altered healthy RPE65 genes. Within days of the treatment, they reported increases in the ability to see dim light.[25]