Routine vision exams help to identify vision changes that may require prescription adjustments, of course, but they can also detect many other things—early sight loss, dry eye syndrome, astigmatism, corneal complications, cataracts, threats to the optic nerve, macular degeneration, glaucoma, and damage from high blood pressure and diabetes.
Many people believe that they see just fine, and perhaps they do. Most do not know, however, that they have actually lost their ability to see clearly at very close range or at farther distances, or that their peripheral (side) vision isn't as broad. They may have also become so accustomed to issues with their eyes, that they have learned workarounds and accepted their difficulties as normal.
Some eye complications, including serious threats to vision and eye health, go undetected until there is an irreversible problem, and can only be caught early through a professional eye exam. Some examples follow.
Finally, modifiable factors that contribute to vision disturbances, such as certain medical conditions and medications, can also be addressed.
Hypertensive retinopathy
Hypertensive retinopathy is damage to the retina caused by high blood pressure (hypertension). The retina is the reason we can see. It is a large collection of cells that capture incoming information and transmit it as both electrical and chemical signals for the brain to create visual pictures. Damage to the retina impairs the transmission of information to the brain and consequently results in blurred vision or even loss of vision entirely.
Macular degeneration
Macular degeneration is a disease that affects central vision. Persons with this disease cannot see fine details, whether looking close or far, though peripheral (side) vision will still be normal. For instance, imagine looking at a clock with hands. With macular degeneration, one might see the clock’s numbers but not the hands.
Age-related macular degeneration (AMD) is very common. In fact, it is a leading cause of vision loss in people 50 years or older. AMD can result in severe loss of central vision, but people rarely go blind from it. Risk factors for AMD include age, smoking, high blood pressure, and a diet high in saturated fat.
Many people don’t realize they have AMD until their vision is very blurry. This is why it is important to have regular visits to an ophthalmologist who can look for early signs of AMD before your loved one has any vision problems.
Glaucoma
Glaucoma is a disease that damages the optic nerve, affecting one's ability to see, as well as the general health of the eye tissue. Fluid builds up in the front part of the eye and causes an increase in pressure. As amazing as the eye is, it is rather fragile, and increased pressure can cause significant and irreversible damage. Your loved one is considered at high risk if at least one or more of these conditions applies:
Diabetes
Family history of glaucoma
African American, aged 50 or older
Hispanic age 65 or older
Open-angle glaucoma. The most common type of glaucoma, it occurs gradually over time. The eye does not drain fluid as well as it should and, as a result, eye pressure builds and damages the optic nerve. This type of glaucoma is painless and vision changes do not occur in the early stages, which is why it's all the more important to get regular eye checks.
Angle-closure glaucoma (also called closed-angle or narrow-angle). This is less common and occurs when the iris (the colored part of the eye) is too close to the drainage angle of the eye and ends up blocking the drainage. When the drainage is completely blocked, eye pressure rises rapidly, and is called an acute attack. This is an eye emergency requiring the attention of an ophthalmologist right away - before irreversible blindness occurs. An acute attack is painful and vision changes occur immediately. Symptoms include:
Sudden blurred vision
Severe eye pain
Unusual headache
Nausea and/or vomiting
Seeing rainbow-colored rings or halos around lights
Many people with angle-closure glaucoma develop it slowly. This is called chronic angle-closure glaucoma. There are no symptoms at first, so someone may not know until they have an acute attack. Again, why regular eye checks are so important.
Glaucoma can often be prevented with early treatment, which is why your loved one should be getting checked once a year if they are at high risk.
