How is nearsightedness diagnosed?

[Trammel]

How is nearsightedness diagnosed?

[Mount Crawford]

Testing for nearsightedness may use several procedures in order to measure how the eyes focus light and to determine the power of any optical lenses needed to correct the reduced vision. As part of the testing, letters on a distance chart are identified. This test measures visual acuity, which is written as a fraction such as 20/40. The top number of the fraction is the standard distance at which testing is performed, twenty feet. The bottom number is the smallest letter size read. A person with 20/40 visual acuity would have to get within 20 feet to identify a letter that could be seen clearly at forty feet in a "normal" eye. Normal distance visual acuity is 20/20, although many people have 20/15 (better) vision. Using an instrument called a phoropter, an optometrist places a series of lenses in front of your eyes and measures how they focus light using a hand held lighted instrument called a retinoscope. The doctor may choose to use an automated instrument that automatically evaluates the focusing power of the eye. The power is then refined by patient's responses to determine the lenses that allow the clearest vision. This testing may be done without the use of eye drops to determine how the eyes respond under normal seeing conditions. In some cases, such as for patients who can't respond verbally, or when some of the eye's focusing power may be hidden, eye drops may be used. They temporarily keep the eyes from changing focus while testing is performed. Using the information obtained from these tests, along with the results of other tests of eye focusing and eye teaming, your optometrist can determine if you have nearsightedness. He or she will also determine the power of any lens correction needed to provide clear vision. Once testing is complete, your optometrist can discuss options for treatment.

[Trommald]

Your eye doctor can diagnose myopia as part of a comprehensive eye examination. He or she will determine if you have myopia by using a standard vision test, where you are asked to read letters on a chart placed at the other end of the room.If the vision test shows that you are nearsighted, your doctor will use certain examination devices to learn what is causing the myopia. By shining a special light into your eyes, a retinoscope will be used to see how light reflects off your retina. As the light is reflected back from inside the eye, it can indicate whether a person is nearsighted or farsighted.Your doctor will also use a phoropter, an instrument that the measures the amount of refractive error you have and helps determine the proper prescription to correct it.

[Mount Croghan]

Your myopia will be diagnosed in a comprehensive eye examination. Your eye doctor will determine if you have myopia by using a standard vision test, where you are asked to read letters on a chart placed at the other end of the room. If the vision test shows that you are nearsighted, your doctor will use certain examination device to learn what is causing the myopia. By shining a special light into your eyes, a retinoscope will be used to see how light reflects off your retina. As the light is reflected back from inside the eye, it can indicate whether a person is nearsighted or farsighted. Your doctor will also use a phoropter, an instrument that the measures the amount of refractive error you have and helps determine the proper prescription to correct it.

[Trammells]

An eye care professional can diagnose nearsightedness and other refractive errors during a comprehensive dilated eye examination. People with this condition often visit their eye care professional with complaints of visual discomfort or blurred vision.Nearsightedness can affect both children and adults. The condition affects about 25 percent of Americans. Nearsightedness is often diagnosed in children between 8 and 12 years of age and may worsen during the teen years. Little change may occur between ages 20 to 40, but sometimes nearsightedness may worsen with age. People whose parents are nearsighted may be more likely to get the condition.