A Guide to Common Eye Diseases

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A Guide to Common Eye Diseases


Child in America getting an eye examAccording to the Centers for Disease Control and Prevention (CDC), more than 4.2 million people in America are legally blind or suffer from poor vision. Although there are a plethora of different diseases and conditions that can result in vision loss, four stand out as the leading causes: glaucoma, diabetic retinopathy, cataracts, and macular degeneration.

What Is Macular Degeneration?

Macular degeneration has the unfortunate honor of being the most common cause of vision loss in people over the age of 60. It’s caused by the deterioration of the macula, or center of the retina. There are two types of age-related macular degeneration: dry and wet.

Macular degeneration is typically an age-related disease, meaning that it’s more common in older adults. Other risk factors for macular degeneration include genetics, smoking, poor diet, and high blood pressure.

Symptoms of macular degeneration include blurriness or loss of vision in the center of your visual field, straight lines appearing wavy, and difficulty seeing in low light. Macular degeneration is a progressive disease, so symptoms will become more severe as time goes on.

While drugs or special supplements can help slow or stop the progression of this disease, there’s currently no cure for macular degeneration. In the meantime, a preventive approach focusing on regular exercise, good diet, not smoking, and maintaining a healthy blood pressure is your best bet.

What Is Glaucoma?

Glaucoma is caused by damage to the optic nerve, usually due to the buildup of fluid in the eye. As the fluid accumulates, it puts increasing pressure on the optic nerve, eventually resulting in the death of some of the nerve fibers in the optic nerve.

Although glaucoma can affect younger people, it’s more common in adults over age 40. Other risk factors for glaucoma include high internal eye pressure, nearsighted- or farsightedness, certain types of eye injuries or surgery, a family history of glaucoma, and being Black, Hispanic, or Asian.

Glaucoma symptoms include patchy blind spots in your vision, tunnel vision, headache, eye pain, blurred vision, seeing halos around light, and eye redness. However, it’s not uncommon for people in the early stages of glaucoma to have no symptoms at all. For that reason, regular checkups with your eye doctor are crucial for catching the disease early. Like macular degeneration, glaucoma is a progressive disease that will eventually result in blindness.

Once your eyes have been damaged by glaucoma, there’s no way to reverse it and regain lost sight. Fortunately, there are a number of effective treatments that can help stop further progression of the disease, including specially medicated eye drops, surgery, and laser therapy.

What Are Cataracts?

A cataract occurs as a result of the lens of the eye becoming cloudy. It can happen in one eye or both.

In most cases, cataracts are age-related. However, certain factors can put you at a higher risk for developing cataracts, including diabetes, smoking, overconsumption of alcohol, family history, eye trauma or surgery, sun exposure, and steroids.

Cataract symptoms often include blurry vision, colors seeming faded, light sensitivity, difficulty seeing in poor light or at night, and double vision.

In their early stages, cataracts can be managed with the use of contacts or glasses. For more advanced cases of cataracts, surgery is often required. Fortunately, cataract surgery is one of the most common procedures performed in the United States, and has a very high success rate.

Diabetic Retinopathy

As the name implies, diabetic retinopathy affects people with diabetes (both Type 1 and 2). Over time, an excess of blood sugar blocks the blood vessels in the retina, causing vision loss and potentially blindness.

Any individual with diabetes can develop diabetic retinopathy. However, people who have had the disease longer, or who don’t manage their blood sugar levels well, are at higher risk. Other risk factors include high blood pressure, high cholesterol, pregnancy, and smoking.

As with glaucoma, the symptoms of diabetic retinopathy are often nonexistent in its early stages. For that reason, it’s important for people with diabetes to get regular eye exams. As the disease gets worse, diabetic retinopathy patients may notice blurry or double vision, dark floating spots or streaks in their vision, pain or pressure in either (or both) eyes, and vision loss.

Damage caused by diabetic retinopathy isn’t reversible. Fortunately, though, the disease is very treatable and preventable. Managing your diabetes and risk factors is the best way to avoid diabetic retinopathy altogether. For people who do require treatment, injections, laser treatments, and surgery can prevent further damage to your vision.

Elderly individual smiling after a new pair of glasses

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