NORMAL VISION
The eye sees normally when light rays focus on the "picture screen" or retina, located at the back of the eye. Clear sight is possible when the lignt rays pass through the cornea, pupil, and lens focusing exactly on the retina.

NEARSIGHTEDNESS OR MYOPIA
If the eye is too long, or the "clear window" called the cornea is too curved, the eye is nearsighted or myopic. Light will focus in front of the retina causing blurred distance vision.

FARSIGHTEDNESS OR HYPEROPIA
If the eye is too short, or the cornea is too flat, light focuses to a point behind the retina at the back of the eye, causing blurred close, and sometimes blurred distance vision as well.

ASTIGMATISM
The eye is astigmatic when the cornea is shaped like the back surface of a teaspoon instead of like the back of a soup spoon. This causes light to focus at more than one point, resulting in distorted vision. Astigmatism commonly occurs along with nearsightedness or farsightedness.

LASIK, LASER Eye Surgery-Flint

LASER-ASSISTED IN-SITU KERATOMILEUSIS (LASIK)
LASIK had its origins about thirty years ago and was originally developed to treat patients who had very poor vision due to corneal disease. It has now evolved into a successful technique for correcting refractive errors. The current procedure, performed on an outpatient basis, involves both the use of conventional and laser surgery to correct nearsightedness, farsightedness and astigmatism. LASIK can correct a much higher degree of nearsightedness with or without astigmatism than any other refractive procedure, with excellent results (the majority of patients achieve 20/40 vision or better).

In performing LASIK, eye drop anesthetic is used to numb the eye. The surgeon then uses a special instrument to cut into and behind a layer of the cornea. A portion of the cornea is peeled back to create a flap and expose the inner portions of corneal tissue. The eye is then positioned under the excimer laser which has been computer programmed to remove microscopic amounts of the internal corneal tissue. Removal of the tissue changes the curvature of the cornea. If the patient is nearsighted, tissue closer to the central part of the cornea is removed to decrease the curvature or flatten the cornea. If a patient is farsighted, tissue in the peripheral part of the cornea is removed to increase the curvature of the cornea. To correct for astigmatism, selected tissue at certain angles is removed to insure that the cornea curves equally in all directions. After the laser has been used, the flap is returned to its original position. The corneal tissue has extraordinary natural bonding qualities that allow effective healing without the use of stitches.

Since only local anesthetic is used, patients remain awake during the procedure. The entire procedure takes only a few minutes and improved vision is often possible on the day following the surgery. Eye drops and night protection are necessary for designated periods of time.

Cataracts
Cataracts occur as part of the normal aging process. Studies show that virtually everyone over age 65 has some cataract formation in their eyes! Cataracts can severely reduce your vision. At one time, cataracts were a leading cause of blindness in the world. But today, fortunately they can be treated. Modern surgical techniques, intraocular lens implantation, and "same day surgery" make cataract surgery safe, fast, and effective.

A cataract occurs when the normally clear lens of the eye becomes cloudy. As the cataract develops, the cloudiness no longer allows the lens to properly focus light on the back of the eye. This unfocused light causes the vision to look blurry or hazy. Development of cataracts has been associated with exposure to ultraviolet radiation. They are particularly prevalent in persons who spend a lot of time in the sun, such as fisherman. There is nothing you can do to prevent the formation of cataracts.Treatment is indicated when decreased vision affects your everyday activities or hobbies.

Diabetic Retinopathy
Diabetes is a disease which affects the blood vessels throughout the body, particularly vessels in the kidney and eye. When the blood vessels in the eye are affected, this is called diabetic retinopathy.

The retina lies in the back of the eye and is a multi-layered tissue which detects visual images and transmits these to the brain. There are major blood vessels which lie on the surface, or the front portion, of the retina. When these blood vessels are damaged due to diabetes, they may leak fluid or blood and grow scar tissue. This leakage affects the ability of the retina to detect and transmit images.

Diabetic retinopathy is the leading cause of new blindness among adults in the United States. If untreated, there is a risk of becoming blind. The longer one has diabetes, the higher the incidence of developing diabetic retinopathy. Approximately 80% of people who have diabetes for 15 years have some damage to their retinal vessels. With today's treatment only a small percentage of people have serious vision problems.

There are two types of diabetic retinopathy. Background retinopathy is considered the early stage. Reading vision is typically not affected, but it can advance and cause severe vision problems. There are usually no symptoms with background diabetic retinopathy. An exam is the only way to diagnose changes in the vessels of your eyes.

When the retinopathy becomes advanced, new vessels grow, or proliferate, in the retina. These new vessels are the body's attempt to overcome and replace the vessels which have been damaged by diabetes. But these new vessels are not normal. They may bleed, which causes vision to become hazy and sometimes causing a total loss of vision. These new vessels can also damage the retina by forming scar tissue and by pulling the retina away from its proper location. This stage, called proliferative retinopathy, requires immediate medical attention. Treatment is necessary to prevent severe loss of vision. Regular eye exams are crucial for all persons with diabetes. The progressing damage to the blood vessels in the eye can be slowed with treatment.

Dry Eyes
The eye has a tear film which coats the outer layer of the eye. This tear film is very important for the lubrication and comfort of the eye as well as for the clarity of vision. As we age, this protective tear film diminishes, and leaves the eye more exposed to the drying effects of the air, wind, and dust. In many people the dryness is worse in the afternoon and evening.

Dry eye is not caused by a lack of tear production. In fact, during dry eye, the eye can still make so many tears that many patients complain of wet eyes and tearing with this malady. That's because the dryness causes the eye to produce more tears in an effort to replace the tear film. Dry eye is probably the most common problem seen in the eye doctor's office.

Dry eye symptoms include burning, stinging or a gritty sensation which may come and go depending on many factors. Itching, tearing and light sensitivity may also occur. Occasionally long strings of mucus can be stretched from a dry eye.

Blinking is very important for the maintenance of the tear film. When performing such activities as reading or working on a computer, we blink less frequently. This aggravates the symptoms of dry eyes. Sometimes environmental factors can also aggravate dry eye symptoms. Dry weather, either in hot or cold temperatures, robs the eye of needed lubricants. Cigarette smoke, fumes, dust and airborne particles are common irritants. In most patients, this condition is not associated with systemic disease.

Treatment helps in most patients. We cannot cure this condition, so treatment is an ongoing project. Usually artificial tears, available over-the-counter, soothe the eyes and give temporary relief. These artificial tears work for only an hour or two, at best, and must be repeated at frequent intervals. Ointments last longer, but they blur vision and are most effective at night.

Newer techniques to treat dry eye include plugs which block the tear duct. These plugs can be placed in the two tear ducts, top and bottom, in both eyes or in only the lower ducts. Some test plugs are also available which dissolve a few days after insertion. If the dry eye symptoms disappear when the temporary plugs are inserted, then permanent plugs should be considered as a treatment option.

Glaucoma

Glaucoma is the leading cause of blindness in the United States. It is a disease that typically affects older people, but it can occur at any age. Loss of vision is preventable if the disease is detected early and treatment is started.

The eye has about 1 million tiny nerve fibers which run from the back of the eye to the brain. These nerve fibers allow us to see. Glaucoma is a disease which causes the destruction of these fibers. It was once thought that the loss of these fibers was due strictly to high pressure in the eye. But now it is known that even patients with normal eye pressure can have glaucoma and loss of these nerve fibers.

In many patients, the disease is not noticed in the early stages, because there is no pain and no noticeable change in vision. Early detection by an eye doctor is the key to the prevention of vision damage from glaucoma. Routine eye examinations are recommended.

Types of Glaucoma
The reason that eye pressure is high in many glaucoma patients is that the drainage system in the eye is not working properly. The fluid in the eye, called aqueous humor, does not flow out of the eye as quickly as it should. The drainage system lies in a part of the eye called the angle, which is between the outer layer and the iris of the eye. This angle can be open or closed.

There are several kinds of glaucoma. The most common form of glaucoma is called chronic open-angle glaucoma. The drainage angle is open in these patients, but the eye fluid does not drain as quickly as it should. Closed-angle glaucoma occurs when the drainage angle closes, and almost no eye fluid can escape. During closed-angle glaucoma, eye pressure can get very high and there is pain. Angle-closure glaucoma is an emergency and must be treated immediately. If the high pressure is allowed to continue for too long, blindness can result.

Some persons are more likely to have glaucoma. These include persons who are older, have nearsightedness, have a family history of glaucoma, have had past eye injury, have diabetes, or have a past history of vascular shock. Also, African Americans are 6 times more likely to have the disease.

Glaucoma is treated with eye drops that lower the eye pressure. If the pressure does not fall to a low enough level with drops, then surgery may be necessary. Glaucoma surgery opens up the drainage system in the angle so that the eye fluid can flow more freely.

Macular Degeneration
The macula is the tiny central part of the retina which is responsible for fine detail vision and for color perception. Macular degeneration is a disease of this very important portion of the retina. It usually affects both eyes, but often begins in one eye.

In many cases, patients are not aware of macular degeneration in one eye, because the other eye compensates for the weaker one. The most common symptoms include difficulty reading, seeing up close or distorted lines. It occurs most often in people over fifty years of age. If you notice a dimness of vision in one or both eyes or if straight lines appear distorted, you should see an eye doctor immediately. There is no cure for macular degeneration, but recent research suggests that certain vitamins and nutrients may slow the progress of the disease in certain patients. If the disease is advancing, laser surgery can be also be used to slow the disease.

If you are over fifty, have your eyes examined regularly. If you have symptoms, report them to your eye doctor immediately before the disease progresses too far.