"Refraction" refers to the total process by which the eye focuses light. Three factors determine the eye's refractive power: the curvature of the cornea, the power of the lens and the overall length of the eyeball. When these elements function properly, light focuses sharply on the retina and gives clear vision at all distances without glasses or contact lenses. Focusing or refractive disorders arise when these elements do not work in harmony with each other. In these cases, light does not focus on the retina and a blurred image is perceived at some or all distances. Common refractive disorders are myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.
Nearsightedness is the most common refractive disorder. It is estimated that one in every four people is myopic, meaning near vision remains clear, but distance is blurred. Myopia is caused by either a long eyeball, a highly curved cornea or both. This causes light to focus in front of the retina. The term "nearsightedness" means you can see objects "near" to you more clearly than distant objects.
Farsighted people usually see distant objects more clearly than close objects. Farsightedness is caused by any combination of a short eyeball and flat corneal curvature. In this case, light hits the retina before it can come into sharp focus.
Astigmatism is caused by asymmetric curvature of the cornea. Instead of being round like a marble, the cornea curvature is like a football. Light is not sharply focused at any distance. Astigmatism often occurs with myopia or hyperopia.
Presbyopia is part of the natural aging process. Everyone experiences the effects of presbyopia, typically starting between the ages of 40-50. This develops as the lens of the eye loses some of its flexibility, making it difficult to focus up close. Mild myopia counteracts presbyopia. That is why if you are slightly myopic, you can remove your glasses and are still able to read. Why do you wear glasses?
PRK (Photo Refractive Keratectomy) started world-wide in 1989. After more than seven years of clinical study and refinements, the FDA approved PRK in October 1995. Subsequently, the treatment of hyperopia and astigmatism has been approved. PRK is a painless outpatient procedure and takes about ten minutes to perform on both eyes. During PRK, the laser treatment is applied to the outer surface of the cornea and no flap is created. However, after having the outer surface of the cornea treated, you must wear a bandage contact lens to facilitate comfort and healing. Typically, this is removed after three days.
"You have a great job! I can only imagine how gratifying it must be to make people feel the way I feel today. I came to you with severe myopia (-13.00 +3.50) and 24 hours after surgery, I was 20/20! You've far exceeded my expectations. I would also like to recognize your staff for the great job they do. They create such a great atmosphere as they share in the patient's excitement and go out of their way to ensure that the patient understands and is comfortable with the process." -David Hughes
LASIK is a treatment used by the world's most experienced refractive surgeons to correct most ranges of nearsightedness, farsightedness and astigmatism. The physicians of the Cincinnati Eye Institute utilize a precise motorized instrument called a microkeratome to create a hinged flap of tissue on the center of the cornea. The flap is lifted back and the laser reshapes the underlying tissue. The flap is then replaced and adheres naturally. LASIK has a lengthy learning curve and consistently good outcomes are gained only by the experience of performing a number of cases. Your choice of a LASIK surgeon can make a major difference in how well you will see. America has many eye surgeons and, as in any profession, levels of ability and quality of outcomes vary. Your lifetime of vision is far too valuable to risk with a surgeon selected simply on the basis of cost.
Once again, the Cincinnati Eye Laser Center takes the lead in ophthalmology with the delivery of the most advanced eye tracking technology now available on the market - the VISX Star S3 ActiveTrak Excimer laser system. This newest generation laser system incorporates the latest active eye-tracking system in addition to many other advancements to help our surgeons deliver the best possible treatment. VISX's patented variable beam technology, allows the fastest treatment time and provides the future platform for custom treatments. Designed to provide better laser vision correction, the ActiveTrak eye tracker is a new 3D eye-tracking technology. With ActiveTrak, the laser detects and compensates for small eye movements by guiding the laser beam to keep it centered precisely over the treatment area. It continuously repositions the laser beam throughout the procedure for greater accuracy and realigns itself between each laser pulse insuring pinpoint accuracy. The eye tracker adds a new level of precision, comfort, and safety. This new technology makes older eye trackers - which require dilation - virtually obsolete. Compared to other trackers, ActiveTrak requires no pupil dilation, which allows the surgeon to center the laser beam more accurately. Not having to be dilated eliminates the inconvenience and discomfort of dilation, and adds to patient confidence with the safety of the procedure. Because vision is not hindered by dilation, most patients are able to appreciate the improvement in their vision immediately after being treated.