VISION CONDITIONS AND EYE DISEASES
Nearsightedness (myopia) is a common vision condition in which you can see objects near to you clearly, but objects farther away are blurry.
The degree of your nearsightedness determines your ability to focus on distant objects. People with severe nearsightedness can see clearly only objects just a few inches away, while those with mild nearsightedness may clearly see objects several yards away.
Nearsightedness may develop gradually or rapidly, often worsening during childhood and adolescence. Nearsightedness tends to run in families.
A basic eye exam can confirm nearsightedness. You can easily correct the condition with eyeglasses or contact lenses. Another treatment option for nearsightedness is surgery.
Farsightedness (hyperopia) is a common vision condition in which you can see distant objects clearly, but objects nearby may be blurry.
The degree of your farsightedness determines your focusing ability. People with severe farsightedness may see clearly only objects a great distance away, while those with mild farsightedness may be able to clearly see objects that are closer.
Farsightedness usually is present at birth and tends to run in families. You can easily correct this condition with eyeglasses or contact lenses. Another treatment option is surgery.
Glaucoma is not just one eye disease, but a group of eye conditions resulting in optic nerve damage, which causes loss of vision. Abnormally high pressure inside your eye (intraocular pressure) usually, but not always, causes this damage.
Glaucoma is the second leading cause of blindness. Sometimes called the silent thief of sight, glaucoma can damage your vision so gradually you may not notice any loss of vision until the disease is at an advanced stage. The most common type of glaucoma, primary open-angle glaucoma, has no noticeable signs or symptoms except gradual vision loss.
Early diagnosis and treatment can minimize or prevent optic nerve damage and limit glaucoma-related vision loss. It’s important to get your eyes examined regularly, and make sure your eye doctor measures your intraocular pressure.
A cataract is a clouding of the normally clear lens of your eye. For people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window. Clouded vision caused by cataracts can make it more difficult to read, drive a car — especially at night — or see the expression on a friend’s face.
Most cataracts develop slowly and don’t disturb your eyesight early on. But with time, cataracts will eventually interfere with your vision.
At first, stronger lighting and eyeglasses can help you deal with cataracts. But if impaired vision interferes with your usual activities, you might need cataract surgery. Fortunately, cataract surgery is generally a safe, effective procedure.
How a cataract affects your vision:
ASTIGMATISM AND PRESBYOPIA
What Is Astigmatism?
Astigmatism is a common eye condition that’s easily corrected by eyeglasses, contact lenses, or surgery.
Astigmatism is characterized by an irregular curvature of the cornea. This is one type of refractive error. Astigmatism occurs in nearly everybody to some degree. For significant curvature, treatment is required.
A person’s eye is naturally spherical in shape. Under normal circumstances, when light enters the eye, it refracts evenly, creating a clear view of the object. However, the eye of a person with astigmatism is shaped more like a football or the back of a spoon. For this person, when light enters the eye it is refracted more in one direction than the other, allowing only part of the object to be in focus at one time. Objects at any distance can appear blurry and wavy.
What Causes Astigmatism?
Astigmatism can be hereditary and is often present at birth. It can also result from pressure from the eyelids on the cornea, incorrect posture, or an increased use of the eyes for close work.
What Are the Symptoms of Astigmatism?
People with undetected astigmatism often experience headaches, fatigue, eyestrain, and blurred vision at all distances. While these symptoms may not necessarily be the result of astigmatism, you should schedule an eye exam if you are experiencing one or more symptoms.
How Are Astigmatisms Diagnosed?
Your optometrist or ophthalmologist can diagnose astigmatism with a thorough eye exam. Astigmatism may occur with other refractive errors such as myopia (nearsightedness) and hyperopia (farsightedness). Unfortunately, astigmatism often goes undetected in school-age children.
Because astigmatisms may increase slowly, you should visit your optometrist or ophthalmologist whenever you notice significant changes in your vision. Optometrists are trained specifically to examine the general health of the eyes and prescribe eyeglasses and contact lenses.
Ophthalmologists provide total eye care, including exams, diagnosis, and treatment of disease through medication and surgery.
How Are Astigmatisms Treated?
Almost all degrees of astigmatism can be corrected with properly prescribed eyeglasses or contact lenses. For a person with only a slight degree of astigmatism, corrective lenses may not be needed at all, as long as other conditions such as nearsightedness or farsightedness are not present. If the astigmatism is moderate to high, however, corrective lenses are probably needed.
Corrective lenses (eyeglasses or contact lenses)
For astigmatism, special corrective lenses called toric lenses are prescribed. Toric lenses have greater light bending power in one direction than the other. After performing various tests, your eye doctor will determine the ideal toric lens prescription for your astigmatism.
Another method for correcting astigmatism is by changing the shape of the cornea through refractive or laser eye surgery . While there is more than one type of refractive surgery, specific treatments are recommended on an individual basis.
Refractive surgeries require healthy eyes that are free from retinal problems, corneal scars, and any eye disease. As technology progresses, it is becoming more and more important that you explore all options and possibilities before deciding which refractive surgery and treatment is right for you.
The gradual loss of your eyes’ ability to focus actively on nearby objects — is a not-so-subtle reminder that you’ve reached middle age. A natural, often annoying part of aging, presbyopia usually becomes noticeable in your early to mid-40s and continues to worsen until around age 60.
You may become aware of presbyopia when you start holding books and newspapers at arm’s length to be able to read them. If you’re nearsighted, you might temporarily manage presbyopia by reading without your glasses.
A basic eye exam can confirm presbyopia. You can correct the condition with nonprescription reading glasses or prescription eyeglasses or contact lenses. Surgery also may be an option.