Periodic comprehensive eye exams by an eye doctor are essential to monitor the health of your eyes and diagnose suspected problems. Checking the position of each eye and its movements will reveal crossed eyes or other forms of strabismus. The exam may include these parts:
An eye chart uses letters of decreasing size to determine the sharpness of your vision at a distance.
The retinoscope projects a thin beam of light into the eye. When used with the rotating lens dial (called the phoropter) the eye doctor measures any refractive error like nearsightedness, farsightedness, or astigmatism.
A slit-lamp microscope exam of the surface of each eye. The same device is used to inspect the eye's internal structures. This is how changes in the clear cornea and lens are identified.
Pressure inside the eye is measured using one of several devices.
Exams with an ophthalmoscope can reveal abnormalities of the retina, the macula, the optic nerve, and other structure inside the eye.
Dilating eye drops may be given in order for the doctor to complete a full exam. The purpose of dilation is to open the pupil or “window” to allow a much better view of the lens, retina, and optic nerve. Although this can cause some temporary blurriness, it is a very important evaluation. Typically, sunglasses are given at the end of an exam to help protect the eyes from sensitivity after the dilation until the effect wears off.
During a cornea transplant, an eye surgeon removes a portion of your cornea and replaces it with a new section of cornea from a donor.
The procedure is also called a corneal transplant or a keratoplasty. About 40,000 cornea transplants are performed in the U.S. every year.
You may need a cornea transplant if your cornea no longer lets light enter your eye properly because of scarring or disease.
If routine testing indicates that you have a refractive error, conventional treatment calls for wearing corrective glasses or contact lenses. Over 150 million people in the US wear corrective lenses. In many cases, surgical correction of refractive errors is possible using modern surgical techniques such as LASIK.
Conventional treatment for disorders such as nearsightedness, farsightedness, and astigmatism typically relies on corrective prescription lenses. Disorders such as cataracts, glaucoma, macular degeneration, and retinal detachment require advanced medical and surgical treatments. Enormous progress in eye surgery has been made over the past few decades. Many people with eye problems previously felt to be untreatable now enjoy improved eyesight and an improved quality of life. This applies to individuals of every age -- infants to senior citizens!
To treat nearsightedness, your eye doctor will usually prescribe lenses to focus visual images correctly on the retina. Depending on the specifics of your eye exam, you may have a choice between wearing conventional eyeglasses and contact lenses.
As an alternative to corrective lenses, surgery can sometimes be performed to treat nearsightedness. Excimer laser treatment (like LASIK) uses a laser beam to remove microscopic amounts of tissue from the cornea. This effectively flattens or steepens the cornea as needed so that light rays focus correctly on the retina. LASIK is safe and effective for most patients with nearsightedness, but only up to a certain level. Some patients with thin corneas, very large pupils, and extreme nearsightedness may not be good laser candidates. There are advanced options for these patients, including surgical correction with implantable contact lenses.