Approximately 11 million Americans 12 years and older could improve their vision through proper refractive correction. More than 3.3 million Americans 40 years and older are either legally blind (having best-corrected visual acuity of 6/60 or worse (=20/200) in the better-seeing eye) or are with low vision (having best-corrected visual acuity less than 6/12 (less than 20/40) in the better-seeing eye, excluding those who were categorized as being blind). The leading causes of blindness and low vision in the United States are primarily age-related eye diseases such as age-related macular degeneration, cataract, diabetic retinopathy, and glaucoma. Other common eye disorders include amblyopia and Strabismus.
Smart Medicine for Your Eyes: A Guide to Natural, Effective and Safe Relief of Common Eye Disorders
The Eye Book: A Complete Guide to Eye Disorders and Health (A Johns Hopkins Press Health Book)
Refractive Errors
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Refractive errors are the most frequent eye problems in the United States. Refractive errors include myopia (near-sightedness), hyperopia (farsightedness), astigmatism (distorted vision at all distances), and presbyopia that occurs between age 40-50 years (loss of the ability to focus up close, inability to read letters of the phone book, need to hold newspaper farther away to see clearly) can be corrected by eyeglasses, contact lenses, or in some cases surgery. Recent studies conducted by the National Eye Institute showed that proper refractive correction could improve vision among 11 million Americans 12 years and older. |
Age-Related Macular Degeneration
Dry AMD: When the macula thins overtime as part of aging process, gradually blurring central vision. The dry form is more common and accounts for 70-90% of cases of AMD and it progresses more slowly than the wet form. Over time, as less of the macula functions, central vision is gradually lost in the affected eye. Dry AMD generally affects both eyes. One of the most common early signs of dry AMD is drusen. |
It is estimated that 1.8 million Americans 40 years and older are affected by AMD and an additional 7.3 million with large drusen are at substantial risk of developing AMD. The number of people with AMD is estimated to reach 2.95 million in 2020. AMD is the leading cause of permanent impairment of reading and fine or close-up vision among people aged 65 years and older.
Cataract
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Cataract is a clouding of the eye’s lens and is the leading cause of blindness worldwide, and the leading cause of vision loss in the United States. Cataracts can occur at any age due to a variety of causes, and can be present at birth. Although treatment for the removal of cataract is widely available, access barriers such as insurance coverage, treatment costs, patient choice, or lack of awareness prevent many people from receiving the proper treatment.
An estimated 20.5 million (17.2%) Americans 40 years and older have cataract in one or both eyes, and 6.1 million (5.1%) have had their lens removed operatively. The total number of people who have cataracts is estimated to increase to 30.1 million by 2020.   Right Eye Cataract Not Repaired, Left Eye Lens Replaced  |
Diabetic Retinopathy
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Diabetic retinopathy (DR) is a common complication of diabetes. It is the leading cause of blindness in American adults. It is characterized by progressive damage to the blood vessels of the retina, the light-sensitive tissue at the back of the eye that is necessary for good vision. DR progresses through 4 stages, mild nonproliferative retinopathy (microaneurysms), moderate nonproliferative retinopathy (blockage in some retinal vessels), severe nonproliferative retinopathy (more vessels are blocked leading to deprived retina from blood supply leading to growing new blood vessels), and proliferative retinopathy (most advanced stage). Diabetic retinopathy usually affects both eyes.
The risks of DR are reduced through disease management that includes good control of blood sugar, blood pressure, and lipid abnormalities. Early diagnosis of DR and timely treatment reduce the risk of vision loss; however, as many as 50% of patients are not getting their eyes examined or are diagnosed too late for treatment to be effective. It is the leading cause of blindness among working-aged adults in the United States ages 20–74. An estimated 4.1 million and 899,000 Americans are affected by retinopathy and vision-threatening retinopathy, respectively. |
Glaucoma
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Glaucoma is a group of diseases that can damage the eye's optic nerve and result in vision loss and blindness. Glaucoma occurs when the normal fluid pressure inside the eyes slowly rises. However, recent findings now show that glaucoma can occur with normal eye pressure. With early treatment, you can often protect your eyes against serious vision loss.
There are two major categories “open angle” and “closed angle” glaucoma. Open angle, is a chronic condition that progress slowly over long period of time without the person noticing vision loss until the disease is very advanced, that is why it is called “sneak thief of sight". Angle closure can appear suddenly and is painful. Visual loss can progress quickly; however, the pain and discomfort lead patients to seek medical attention before permanent damage occurs. |
Estimated Growth in Population
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During the next three decades, the population of adults with vision impairment and age-related eye diseases is estimated to double because the rapidly aging U.S. population. In addition, the epidemic of diabetes as well as other chronic diseases will contribute to an increasing population of people who experience vision loss.
A recent CDC investigation (Saaddine, Honeycutt, Narayan, Zhang, Klein, & Boyle, 2008) revealed that eye diseases associated with diabetes are likely to surge during the next four decades reflecting overall changes in the population as well as improved treatment of diabetes and survival among those who experience diabetes. The number of people who experience diabetic retinopathy is expected to triple between 2005 to 2050 from 5.5 million to 16 million people. |
| Older people are more likely to experience vision loss because of age-related eye diseases. Estimated specific prevalence rates for blindness among Americans aged 40 years and older, by age group and race/ethnicity. |  |
Amblyopia
Amblyopia, also referred to as “lazy eye,” is the most common cause of vision impairment in children. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. Conditions leading to amblyopia include; strabismus, an imbalance in the positioning of the two eyes; more nearsighted, farsighted, or astigmatic in one eye than the other eye, and rarely other eye conditions such as cataract.
Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood, and is the most common cause of permanent one-eye vision impairment among children and young and middle-aged adults. An estimated 2%–3% of the population suffers from amblyopia.
Treatment
How is amblyopia treated in children?
Treating amblyopia involves making the child use the eye with the reduced vision (weaker eye). Currently, there are two ways used to do this:
Atropine
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A drop of a drug called atropine is placed in the stronger eye once a day to temporarily blur the vision so that the child will prefer to use the eye with amblyopia. Treatment with atropine also stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely. |
Patching
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An opaque, adhesive patch is worn over the stronger eye for weeks to months. This therapy forces the child to use the eye with amblyopia. Patching stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely.
Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. However, surprising results from a nationwide clinical trial show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children. This study shows that age alone should not be used as a factor to decide whether or not to treat a child for amblyopia. |
Eye Patch for Children to Treat Amblyopia- (1) Patch Per Order
45 Lazy Eye Exercises: Eye Patch Exercises To Improve Vision for Those Who Suffer From Amblyopia
Can amblyopia be treated in adults?
Studies are very limited at this time and scientists don’t know what the success rate might be for treating amblyopia in adults. During the first six to nine years of life, the visual system develops very rapidly. Complicated connections between the eye and the brain are created during that period of growth and development. Scientists are exploring whether treatment for amblyopia in adults can improve vision.
Current Research
What research is being done?
Findings from the clinical study, An Evaluation Of Treatment Of Amblyopia In Children 7 To (less than) 18 Years Old (ATS3), show that many children age seven through 17 with amblyopia (lazy eye) may benefit from treatments that are more commonly used on younger children. Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. Read more about the ATS3.
The NEI is currently supporting the Amblyopia Treatment Study: Occlusion Versus Pharmacologic Therapy for Moderate Amblyopia (ATS) to determine whether patching or eyedrops is a better treatment for amblyopia. Recent results for the ATS found that the atropine eyedrops, when placed in the unaffected eye once a day, work as well as eye patching and may encourage better compliance. The study was conducted at 47 clinical sites throughout North America. Read more about the ATS.
In addition, A Randomized Trial Comparing Part-time Versus Minimal-time Patching for Moderate Amblyopia (Two v. Six) is being conducted to determine whether the visual acuity improvement obtained with part-time (6 hours) patching is equivalent to the visual acuity improvement obtained with minimal patching (2 hours) for moderate amblyopia. Recent findings show that patching the unaffected eye of children with moderate amblyopia for two hours daily works as well as patching the eye for six hours. Shorter patching time should lead to better compliance with treatment and improved quality of life for children with amblyopia. Read more about the Two v. Six study.
The NEI is also supporting other clinical studies on amblyopia.
Strabismus
Strabismus involves an imbalance in the positioning of the two eyes. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Strabismus is caused by a lack of coordination between the eyes. As a result, the eyes look in different directions and do not focus simultaneously on a single point. In most cases of strabismus in children, the cause is unknown. In more than half of these cases, the problem is present at or shortly after birth (congenital strabismus). When the two eyes fail to focus on the same image, there is reduced or absent depth perception and the brain may learn to ignore the input from one eye, causing permanent vision loss in that eye (one type of amblyopia).
Eye Health Tips
Your eyes are an important part of your health. You can do many things to keep them healthy and make sure you’re seeing your best. Follow these simple guidelines for maintaining healthy eyes well into your golden years.
Have a comprehensive dilated eye exam. You might think your vision is fine or that your eyes are healthy, but visiting your eye care professional for a comprehensive dilated eye exam is the only way to really be sure. When it comes to common vision problems, some people don’t realize they could see better with glasses or contact lenses. In addition, many common eye diseases, such as glaucoma, diabetic eye disease, and age-related macular degeneration, often have no warning signs. A dilated eye exam is the only way to detect these diseases in their early stages.
During a comprehensive dilated eye exam, your eye care professional places drops in your eyes to dilate, or widen, the pupil to allow more light to enter the eye—the same way an open door lets more light into a dark room. This process enables your eye care professional to get a good look at the back of the eyes and examine them for any signs of damage or disease. Your eye care professional is the only one who can determine if your eyes are healthy and if you’re seeing your best.
Know your family’s eye health history. Talk to your family members about their eye health history. It’s important to know if anyone has been diagnosed with an eye disease or condition, since many are hereditary. This information will help to determine if you’re at higher risk for developing an eye disease or condition.
Eat right to protect your sight. You’ve heard that carrots are good for your eyes. But eating a diet rich in fruits and vegetables—particularly dark leafy greens, such as spinach, kale, or collard greens—is important for keeping your eyes healthy, too. Research has also shown there are eye health benefits from eating fish high in omega-3 fatty acids, such as salmon, tuna, and halibut.
Maintain a healthy weight. Being overweight or obese increases your risk of developing diabetes and other systemic conditions, which can lead to vision loss, such as diabetic eye disease or glaucoma. If you’re having trouble maintaining a healthy weight, talk to your doctor.
Wear protective eyewear. Wear protective eyewear when playing sports or doing activities around the home. Protective eyewear includes safety glasses and goggles, safety shields, and eye guards specially designed to provide the correct protection for the activity in which you’re engaged. Most protective eyewear lenses are made of polycarbonate, which is 10 times stronger than other plastics. Many eye care providers sell protective eyewear, as do some sporting goods stores.
Quit smoking or never start. Smoking is as bad for your eyes as it is for the rest of your body. Research has linked smoking to an increased risk of developing age-related macular degeneration, cataract, and optic nerve damage, all of which can lead to blindness.
Be cool and wear your shades. Sunglasses are a great fashion accessory, but their most important job is to protect your eyes from the sun’s ultraviolet rays. When purchasing sunglasses, look for ones that block out 99 to 100 percent of both UV-A and UV-B radiation.
Give your eyes a rest. If you spend a lot of time at the computer or focusing on any one thing, you sometimes forget to blink and your eyes can get fatigued. Try the 20-20-20 rule: Every 20 minutes, look away about 20 feet in front of you for 20 seconds. This short exercise can help reduce eyestrain.
Clean your hands and your contact lenses—properly. To avoid the risk of infection, always wash your hands thoroughly before putting in or taking out your contact lenses. Make sure to disinfect contact lenses as instructed and replace them as appropriate.
Practice workplace eye safety. Employers are required to provide a safe work environment. When protective eyewear is required as a part of your job, make a habit of wearing the appropriate type at all times, and encourage your coworkers to do the same.