What is going on in the body?

Common vision changes can include - but are not limited to: · blurry vision · double vision · cloudy vision

Vision changes can be caused by anything from normal aging to life-threatening conditions. The exact changes in the body will depend on the specific cause and type of vision change.

What are the signs and symptoms of the condition?

Kinds of vision changes include: · decreased sharpness of vision, which means either being unable to focus on objects up close or far away, or both · double vision, which means seeing two of everything · loss of peripheral, or side, vision · total loss of vision, or blindness · cloudy vision, which feels as though the person is looking through a dirty windshield · "blind spots," which means the person has areas of vision where he or she can only see blackness

What are the causes and risks of the condition?

The possible causes of vision changes include: · refractive errors, such as being nearsighted, farsighted or having presbyopia. Presbyopia is when a person has a hard time seeing things up close, due to age-related changes in the eye. This condition affects most people over age 50. It's the reason older people often need bifocals or reading glasses. · infections of the eye, such as conjunctivitis or keratitis · cataracts, a common condition in older adults caused by changes in the lens of the eye · glaucoma, a condition caused by increased pressure within the eye · damage or inflammation of the nerves of the eye · damage to the vision areas of the brain, due to a stroke or brain tumor · damage to the retina, the part of the eye that is similar to the film inside a camera. The retina can be damaged in diabetes, macular degeneration, or retinal detachment. · trauma, or injury, to the eye · strabismus, sometimes known as lazy eye, in which the eyes don't line up properly · temporal arteritis, an inflammation of the arteries that supply blood to the eye · vitamin A deficiency · medicines, such as the heart medicine digitalis, or the antibiotic ethambutol

Other causes of vision changes are possible. Sometimes, no cause can be found.

What can be done to prevent the condition?

Prevention depends on the cause. Early detection and treatment of glaucoma can often prevent vision loss. Control of diabetes can help prevent vision changes caused by diabetic retinopathy. Frequent hand washing and not touching the eyes with the hands helps prevent conjunctivitis. Many cases of vision changes cannot be prevented.

How is the condition diagnosed?

A history and physical exam, including an examination of the eye, are done first. In an eye exam, the person may be asked to read an eye chart. Special instruments may be used, and the pressure inside the eye may be measured. Eye drops can be put into the eye to make the pupils get bigger. This helps the doctor see the inside of the eye better.

The doctor will also need to know the kind of vision changes the person has noticed as well as: · when the vision change started · whether it came on quickly or slowly · whether one or both eyes are affected · whether near vision, far vision, or both, is affected · whether there is any pain associated with the vision change · what medicines the person takes · what other medical conditions the person has · whether there is any family history of vision changes

In addition, the doctor may ask about other symptoms, such as: · headache · nausea · vomiting · weakness · muscle pains

These steps may be all that's needed to make the diagnosis. In other cases, further testing is needed.

The tests that are ordered vary, depending on the suspected cause. A cranial CT scan may be done if a brain tumor or stroke is suspected. A blood test can help diagnose temporal arteritis or diabetes.

What are the long-term effects of the condition?

Long-term effects depend on the cause. Presbyopia causes a permanent loss of vision in near objects. But reading glasses or bifocals are the only treatment needed and there are no other long- term effects. A brain tumor can cause death. Glaucoma, macular degeneration, and diabetes can all result in permanent blindness or vision changes.

What are the risks to others?

Vision changes themselves pose no risks to others unless the person engages in dangerous activities such as driving. If the cause of the vision change is an eye infection, such as conjunctivitis or keratitis, the infection may be catching in some cases.

What are the treatments for the condition?

Treatment is directed at the cause. Medicines are often used to control diabetes or glaucoma. Retinal detachment, cataracts, some types of glaucoma, and brain tumors can be treated with surgery. Eye infections may need to be treated with antibiotics. Nearsightedness is usually treated with glasses or contact lenses.

What are the side effects of the treatments?

Side effects depend on the treatments used. All medicines may have side effects. For example, those used to control diabetes may cause liver damage or allergic reactions. Surgery carries a risk of bleeding, infection, or loss of vision. Contact lenses may irritate the eyes or result in eye infections.

What happens after treatment for the condition?

Treatment varies according to the cause of the vision change. After a person gets glasses, no further treatment may be needed aside from periodic checkups. People who have diabetes or glaucoma usually need close monitoring and treatment for life. Macular degeneration often causes vision to get worse over time, so treatment may change.

How is the condition monitored?

The doctor should be told about any changes in vision or the responses to treatments. Repeat eye exams are advised for many causes of vision changes. Children with a lazy eye may need close monitoring along with surgery, special glasses, or a patch over one eye.