Frequently Asked Questions

Nearsightedness, or myopia, as it is medically termed, is a vision condition in which people can see close objects clearly, but objects farther away appear blurred. People with myopia can have difficulty clearly seeing a movie or TV screen, a whiteboard in school or while driving.

Myopia occurs if the eyeball is too long or the cornea (the clear front cover of the eye) is too curved. As a result, the light entering the eye isn’t focused correctly, and distant objects look blurred.

Myopia affects nearly 30 percent of the U.S. population. While the exact cause of myopia is unknown, there is significant evidence that many people inherit myopia, or at least the tendency to develop myopia. If one or both parents are nearsighted, there is an increased chance their children will be nearsighted.

arsightedness, or hyperopia, as it is medically termed, is a vision condition in which distant objects can be seen clearly, but close ones do not come into proper focus. Farsightedness is due to the eye not bending light properly so it focuses in front of the back of the eye or the cornea has too little curvature. In these cases, your eye can’t correctly focus the light that enters.

Common signs of hyperopia include difficulty concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, and irritability or nervousness after sustained concentration.

Common vision screenings, like the ones done in schools, often don’t detect hyperopia. However, a comprehensive optometric examination will include the necessary testing to diagnose hyperopia. If needed, your optometrist can offer treatment options.

Astigmatism is a common vision condition that causes blurred vision. It occurs when the cornea (the clear front cover of the eye) is irregularly shaped or sometimes because of the curvature of the lens inside the eye.

An irregularly shaped cornea or lens prevents light from focusing properly on the retina, the light-sensitive surface at the back of the eye. As a result, vision becomes blurred at any distance. This can lead to eye discomfort and headaches.

Astigmatism frequently occurs with other vision conditions like myopia (nearsightedness) and hyperopia (farsightedness). Together these vision conditions are referred to as refractive errors because they affect how the eyes bend or “refract” light.

There are many causes to astigmatism. It can be hereditary and is usually present from birth. It can decrease or increase over time.

Presbyopia is a vision condition in which the shape of the crystalline lens of your eye changes. These changes make it difficult to focus on close objects.

Presbyopia may seem to occur suddenly, but sight reduction occurs over several years. Presbyopia usually becomes noticeable in the early to mid-40s, but the reduction of your focusing starts as early as childhood.

Presbyopia is a natural part of the aging process of the eye. It is not a disease, and it cannot be prevented.

Some signs of presbyopia include holding reading materials at arm’s length, blurred vision at normal reading distance and eye fatigue along with headaches when doing close work. A comprehensive optometric examination will include testing for presbyopia.

Amblyopia (lazy eye) is the decrease of vision in one or both eyes due to abnormal vision development during childhood. The vision process involves both the eyes and the brain. Amblyopia is the failure of the vision-sensing portions of the brain to develop normally, which results in blurry vision. It is one of the leading causes of vision loss in children.

Amblyopia is generally the result of poor early visual development. It usually occurs before the age of 8. Infants born prematurely or with low birth weight are at a greater risk for developing the condition.

An estimated 2 to 4 percent of children have amblyopia. The chance of amblyopia developing during adulthood is very small. Early detection and treatment of amblyopia and significantly unequal refractive errors can reduce the chances of one eye becoming amblyopic.

Crossed eyes, or strabismus, is a condition in which both eyes do not look at the same place at the same time. It usually occurs in people who have poor eye muscle control or are very farsighted.

Six muscles attach to each eye to control how it moves. The muscles receive signals from the brain that direct their movements. Normally, the eyes work together so they both point at the same place. When problems develop with eye movement control, an eye may turn in, out, up or down. The eye turning may occur all the time or may appear only when the person is tired, ill, or has done a lot of reading or close work. In some cases, the same eye may turn each time. In other cases, the eyes may alternate turning.

Orthokeratology is a process that uses specially designed GP contact lenses to temporarily reshape the contour of the cornea to reduce myopia (nearsightedness).

Orthokeratology is nicknamed “ortho-k” and sometimes called corneal reshaping (CR), corneal refractive therapy or vision shaping.

Some new ortho-k lens designs are also available for farsightedness and presbyopia. Research has also demonstrated that orthokeratology lens designs slow the progression of myopia.

Good candidates for orthokeratology include youngsters age 8 to 12 with progressive myopia, as well as most adolescents and adults, although the best success is with people under age 40. Ortho-k is recommended for low to mild nearsightedness (-4 diopters or less).

People who are not good candidates include those with dry eye syndrome, a large pupil size, or high myopia.

A cataract is a cloudy or opaque area in the normally clear lens of the eye. Depending upon its size and location, it can interfere with normal vision. Most cataracts develop in people over age 55, but they occasionally occur in infants and young children. Usually cataracts develop in both eyes, but one may be worse than the other.

Cataracts generally form very slowly. Signs and symptoms of a cataract may include:

• Blurred or hazy vision
• Reduced intensity of colors
• Increased sensitivity to glare from lights, particularly when driving at night
• Increased difficulty seeing at night
• Change in the eye’s refractive error, or prescription

There is no treatment to prevent or slow cataract progression. In age-related cataracts, changes in vision can be very gradual. Some people may not initially recognize the visual changes. However, as cataracts worsen, vision symptoms increase.

Age-related macular degeneration (AMD) is an acquired eye disorder and a leading cause of legal blindness in people over age 60. AMD affects the macula (the central part of the retina), which is responsible for providing the clear, sharp vision needed for reading, writing, driving and other visually demanding activities.

The severity of this condition varies depends on the individual patient. Many people with AMD lose some central vision in one or both eyes.

Approximately 90 percent of patients with AMD have a non-exudative (or dry) form of the disease. In this form of the disease, dry, atrophic scars develop in the macular area. Typically, non-exudative AMD patients lose vision gradually.

Only 10 percent of patients develop an exudative (or wet) form of the disease. In the wet form of the disease, fluid beneath the retina leaks. Compared with non-exudative patients, exudative patients lose central vision more rapidly.

Patients with exudative AMD who are identified early in the disease process can be treated with laser photocoagulation. Other treatments include photodynamic therapy and surgical transplantation of the macula.

Diabetic retinopathy is a condition that may occur in people who have diabetes. It causes progressive damage to the retina, the light-sensitive lining at the back of the eye. Diabetic retinopathy is a serious sight-threatening complication of diabetes.

Diabetes interferes with the body’s ability to use and store sugar (glucose). The disease is characterized by too much sugar in the blood, which can cause damage throughout the body, including the eyes.

Over time, diabetes damages small blood vessels throughout the body, including the retina. Diabetic retinopathy occurs when these tiny blood vessels leak blood and other fluids. This causes the retinal tissue to swell, resulting in cloudy or blurred vision. The condition usually affects both eyes. The longer a person has diabetes, the more likely they will develop diabetic retinopathy. If left untreated, diabetic retinopathy can cause blindness.

Hypertensive retinopathy is retinal vascular damage caused by hypertension. Signs usually develop late in the disease.

Funduscopic examination shows arteriolar constriction, arteriovenous nicking, vascular wall changes, flame-shaped hemorrhages, cotton-wool spots, yellow hard exudates, and optic disk edema.

Treatment is directed at controlling blood pressure and, when vision loss occurs, treating the retina.

Glaucoma is a group of eye disorders that lead to progressive damage to the nerve that connects the eye to the brain called the optic nerve. People with glaucoma can lose nerve tissue, resulting in vision loss.

The optic nerve is a bundle of about 1 million individual nerve fibers that transmits the visual signals from the eye to the brain. In the most common form of glaucoma, primary open-angle glaucoma, the fluid pressure inside the eye increases. This increase in pressure may cause progressive damage to the optic nerve and loss of nerve fibers. Advanced glaucoma may even lead to blindness.

Not everyone with high eye pressure will develop glaucoma, and some people with normal eye pressure will develop glaucoma. When the pressure inside a person’s eye is too high for a particular optic nerve, whatever that pressure measurement may be, glaucoma will develop.

If you see dark specks or flashes of light, it’s possible you could have posterior vitreous detachment (PVD), an eye problem many people have as they age.

As you get older, a gel inside your eye — called vitreous gel — can shrink. It can slowly detach (pull away) from your retina. That’s the nerve layer in the back of your eye that helps you focus on the images you see.

Vision problems caused by PVD usually get better over a few weeks. In fact, many people don’t have any symptoms, so they may never know they had it.

But for other people, PVD can cause health issues, such as bleeding and tears. If it’s not treated in those cases, it can lead to permanent vision loss if the gel is detached from your retina.

A corneal ulcer (also known as keratitis) is an open sore on the cornea. The cornea covers the iris and the round pupil, much like a watch crystal covers the face of a watch. A corneal ulcer usually results from an eye infection, but severe dry eye or other eye disorders can cause it.

Symptoms of corneal ulcers include:

• redness of the eye
• severe pain and soreness of the eye
• the feeling of having something in your eye
• tearing
• pus or other discharge
• blurred vision
• sensitivity to light
• swelling of the eyelids
• a white spot on your cornea that you may or may not be able to see when looking in the mirror

Keratoconus is a vision disorder that occurs when the normally round cornea (the front part of the eye) becomes thin and irregular (cone) shaped. This abnormal shape prevents the light entering the eye from being focused correctly on the retina and causes distortion of vision.

In its earliest stages, keratoconus causes slight blurring and distortion of vision and increased sensitivity to glare and light. These symptoms usually appear in the late teens or early 20s. Keratoconus may progress for 10-20 years and then slow in its progression. Each eye may be affected differently.

As keratoconus progresses, the cornea bulges more and vision may become more distorted. In a small number of cases, the cornea will swell and cause a sudden and significant decrease in vision. The swelling occurs when the strain of the cornea’s protruding cone-like shape causes a tiny crack to develop. The swelling may last for weeks or months as the crack heals and is gradually replaced by scar tissue.

If this sudden swelling does occur, your doctor can prescribe eyedrops for temporary relief, but there are no medicines that can prevent the disorder from progressing.