ophthalmoscopy

Even if your eyes feel healthy, you could have a problem and not know it. That's why regular eye exams are so important. Refractive errors are the most common type of vision problem that makes it hard to see clearly. But some eye conditions or diseases don't have any symptoms and can lead to a permanent loss of vision.

Some common eye diseases and conditions include:

• Cataracts, which happens when the clear lens in the front of your eye becomes cloudy. Cataracts are common as you get older and can lead to vision loss.
• Optic nerve disorders, which includes glaucoma. Glaucoma usually happens when the fluid pressure inside your eyes slowly rises.
• Retinal disorders, which are problems with the nerve layer at the back of your eye.
• Macular degeneration, which is a disease that destroys your sharp, central vision.
• Diabetic eye problems, which can cause vision loss and blindness.
• Conjunctivitis, which is an infection also known as pink eye. It can cause pink or red itchy eyes. Some types of pink eye can spread very easily.

Some eye conditions and diseases do not always have symptoms. Early detection through a comprehensive dilated eye exam could help your eye care provider detect diseases in the early stages. Proper treatment could help slow or prevent vision loss.

Get regular eye exams and call your eye care professional right away if you notice any of these symptoms:

• A sudden change in vision
• Everything looks dim
• Flashes of light
• Eye pain
• Double vision
• Fluid coming from your eye
• Inflammation (swelling)

Getting older increases your risk of some eye diseases. Other things that may put you at a higher risk of some eye diseases can include if you:

• Are overweight or obese
• Have a family history of eye disease
• Are African American, Hispanic, or Native American
• Have certain health conditions such as Diabetic eye problems, or high blood pressure

Treatment may depend on the eye condition or disease but can include:

• A new prescription for eyeglasses or contacts
• Use of bright lights or magnifying lenses for reading and other activities
• Medicines
• Prescription eye drops or ointments
• Laser treatment
• Surgery

Depending on your eye condition or disease, treatment may slow vision loss but may not restore vision. Talk to your provider about what treatment is best for you.

Your best defense is to have regular checkups. Be sure to tell your provider if any eye diseases run in your family.

You can also help take care of your vision by making lifestyle changes to lower your risk of health conditions that can cause vision problems. This could include by:

• Protecting your eyes from the sun
• Wearing protective eyewear while using tools or playing certain sports
• Getting regular physical activity
• Staying at a healthy weight
• Quitting smoking (or not starting)
• Eating a healthy diet

NIH: National Eye Institute

Glaucoma is a group of diseases that can damage the optic nerve of one, or both, of your eyes. This can result in vision loss. There are different types of glaucoma, but the most common type is open-angle glaucoma. Other less common types include angle-closure glaucoma, and congenital glaucoma.

You may not have any symptoms of glaucoma. Regular eye exams by an eye care provider can check for glaucoma and other eye problems to help protect your vision. Treatments that lower eye pressure help slow the disease. Without treatment, glaucoma can eventually lead to blindness.

Medical experts aren't sure what causes glaucoma, but the most common types usually happen when the fluid pressure inside your eye slowly rises, damaging the optic nerve. Other types of glaucoma may be caused by medical conditions, or a baby may be born with it.

Not everyone with high eye pressure develops glaucoma. Some people may even get glaucoma with normal eye pressure. The amount of pressure your optic nerve can handle is different for each person. Getting regular dilated eye exams helps your provider figure out what level of eye pressure is normal for you.

Often there are no symptoms of glaucoma at first. Or symptoms may start so slowly that you may not notice them. Without treatment, you slowly lose your peripheral (side) vision. It may seem like you're looking through a tunnel. Over time, your straight-ahead vision may decrease until no vision remains.

If you have sudden symptoms of intense eye pain, blurry vision, red eyes, or an upset stomach (nausea), you need to go to your eye care provider or an emergency room right away. These could be symptoms of angle-closure glaucoma. This less common type of glaucoma causes fluid to build up quickly in your eye.

A comprehensive eye exam can tell if you have glaucoma. This would include:

• A dilated eye exam. This involves getting eye drops that dilate (widen) your pupils. This allows more light to enter your eye. Your eye care provider examines your eyes using a special magnifying lens. This provides a clear view of important tissues at the back of your eye to check for glaucoma or other eye problems. For a few hours after the exam your vision may be blurry and sensitive to light, so you will need someone to take you home.
• Visual field testing. This check of your peripheral (side) vision allows your eye care provider to find out how well you can see objects off to the side of your vision without moving your eyes.
• Tonometry. This measures the pressure inside your eye.

If you're at higher risk for glaucoma, you should get comprehensive eye exams every one to two years. You're at higher risk if you:

• Are Black or African American and over age 40
• Are over age 60, especially if you're Hispanic or Latino
• Have a family history of glaucoma

You're also at higher risk if you have high blood pressure or diabetes and should get a dilated eye exam at least once a year. Talk with your provider about your risk and how often you should get your eyes checked.

Early treatment can help protect your eyes against vision loss. There is no cure, but glaucoma can usually be controlled. Without treatment it can eventually cause blindness. Treatments can include:

• Prescription eye drops are the most common treatment to lower the pressure in your eye and prevent damage to your optic nerve.
• Other treatments may include oral medicines, laser treatment, and/or surgery.

A combination of these treatments may be used to lower eye pressure and help drain the fluid out of your eye.

There is no way to prevent glaucoma. Eye exams can help find glaucoma or other eye problems before they can affect your vision. If you have glaucoma, be sure to continue with treatment to prevent your vision from getting worse.

NIH: National Eye Institute

Macular degeneration, or age-related macular degeneration (AMD), is a leading cause of vision loss in Americans 60 and older. It is a disease that destroys your sharp, central vision. You need central vision to see objects clearly and to do tasks such as reading and driving.

AMD affects the macula, the part of the eye that allows you to see fine detail. It does not hurt, but it causes cells in the macula to die. There are two types: wet and dry. Wet AMD happens when abnormal blood vessels grow under the macula. These new blood vessels often leak blood and fluid. Wet AMD damages the macula quickly. Blurred vision is a common early symptom. Dry AMD happens when the light-sensitive cells in the macula slowly break down. You gradually lose your central vision. A common early symptom is that straight lines appear crooked.

Regular comprehensive eye exams can detect macular degeneration before the disease causes vision loss. Treatment can slow vision loss. It does not restore vision.

NIH: National Eye Institute

The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting the back of each eye (your retina) to your brain. Damage to an optic nerve can cause vision loss. The type of vision loss and how severe it is depends on where the damage occurs. It may affect one or both eyes.

There are many different types of optic nerve disorders, including:

• Glaucoma is a group of diseases that are the leading cause of blindness in the United States. Glaucoma usually happens when the fluid pressure inside the eyes slowly rises and damages the optic nerve.
• Optic neuritis is an inflammation of the optic nerve. Causes include infections and immune-related illnesses such as multiple sclerosis. Sometimes the cause is unknown.
• Optic nerve atrophy is damage to the optic nerve. Causes include poor blood flow to the eye, disease, trauma, or exposure to toxic substances.
• Optic nerve head drusen are pockets of protein and calcium salts that build up in the optic nerve over time

Contact your health care provider if you are having vision problems. Tests for optic nerve disorders may include eye exams, ophthalmoscopy (an examination of the back of your eye), and imaging tests. Treatment depends on which disorder that you have. With some optic nerve disorders, you may get your vision back. With others, there is no treatment, or treatment may only prevent further vision loss.

The retina is a layer of tissue in the back of your eye that senses light and sends images to your brain. In the center of this nerve tissue is the macula. It provides the sharp, central vision needed for reading, driving and seeing fine detail.

Retinal disorders affect this vital tissue. They can affect your vision, and some can be serious enough to cause blindness. Examples are:

• Macular degeneration - a disease that destroys your sharp, central vision
• Diabetic eye disease
• Retinal detachment - a medical emergency, when the retina is pulled away from the back of the eye
• Retinoblastoma - cancer of the retina. It is most common in young children.
• Macular pucker - scar tissue on the macula
• Macular hole - a small break in the macula that usually happens to people over 60
• Floaters - cobwebs or specks in your field of vision

NIH: National Eye Institute

Vision impairment is the loss of vision. It includes blindness, which means that you have lost all or most of your sight. It also includes low vision, which means you have some vision, but the vision loss makes it hard to do everyday activities. You may have trouble reading, shopping, cooking, writing, and watching TV. Low vision can't be fixed with glasses, contact lenses, medicine, or surgery.

Aging doesn't cause vision loss on its own. But many diseases that are more common in older adults can cause it. The leading causes of low vision and blindness in the United States are age-related eye diseases such as macular degeneration, cataracts, and glaucoma. Other eye disorders, eye injuries, and birth defects can also cause vision loss.

Vision impairment is diagnosed with a dilated eye exam. Early warning signs of a vision problem can include not being able to see well enough to:

• Do everyday tasks like reading and driving
• Recognize people's faces
• Tell the difference between colors
• See the television or computer screen clearly

You can have these symptoms even though you are wearing glasses or contacts.

There are several types of low vision. Which type you have depends on the condition that caused your low vision.

Common types of low vision include:

• Central vision loss (not being able to see things in the center of your vision)
• Peripheral (side) vision loss (not being able to see things out of the corners of your eyes)
• Night blindness (not being able to see in low light)
• Blurry or hazy vision

Low vision is permanent. Glasses, medicine, and surgery can't cure low vision. But sometimes they can improve your vision, help you do everyday activities more easily, or keep your remaining vision.

Your treatment options will depend on the condition that caused your low vision. Ask your eye doctor which treatments might help you. They may recommend vision aids or vision rehabilitation, which might make everyday activities easier.

Vision rehabilitation teaches you how to live with your vision loss. It may include:

• Showing you how to use a magnifying device or screen readers for reading
• Helping you set up your home so you can move around more easily
• Employment and job training
• Assistive devices, like lighting and reading stands

Your provider may suggest other resources, such as transportation and household services, to help you cope with your vision loss.

The sooner vision loss or eye disease is found and treated, the greater your chances of keeping your remaining vision. Whatever the cause, lost vision cannot be restored. But it can be managed. A loss of vision means you may have to reorganize your life and learn new ways of doing things. Your provider may make suggestions to help make life easier. These may include:

If you have some vision:

• Visual aids such as magnifiers
• Telescopic glasses or monoculars for seeing distance
• Large print books
• Clocks with larger numbers
• Brighter lights
• Anti-glare sunglasses or glare shields

If you have no vision (blindness):

• Devices like text-reading software and braille books

You can help take care of your vision by:

• Having regular comprehensive eye exams by an eye care professional
• Wearing sunglasses and protective eyewear to protect your eyes
• Making lifestyle changes to lower your risk of health conditions that can cause vision problems:
  • Getting regular physical activity
  • Staying at a healthy weight
  • Quitting smoking (or not starting)
  • Eating a healthy diet

NIH: National Eye Institute