Like any other medical exam, an eye exam consists of several procedures. Several tests can be conducted on the patient's eyes to determine if they are healthy or not. In many cases, a basic set of routine tests will be conducted. Lengthier diagnostic tests may be necessary for patients with a history of eye problems.
Cover tests are the most common tests given by vision specialists. Often the first test given during the eye exam, it involves simply staring at a chart while reading off the letters on the chart. One eye is covered during the first part of the test while the other eye is covered during the second half.
Retinoscopies are another basic exam a vision specialist may use to determine a person's eye care needs. After dimming the lights, the doctor usually examines the patient's eye with a light as the patient stares at the letter chart. As the physician looks into the patient's eye, he or she places a machine in front of the patient and flips various lenses in front of the patient's eyes.
The retinoscopy test can determine an approximate value for the patient's vision prescription, if necessary, based on the way the light reflects from the patient's eyes. For a complete prescription, an eye care provider will usually conduct a refraction exam. During this procedure, another machine called a phoropter will be placed in front of the patient's eyes. The patient will be asked to determine which of two lenses in a long series of choices appears clearer.
Refraction tests can tell whether a person is nearsighted, farsighted, or has astigmatism or presbyopia, as well as at what level these conditions are present. The physician may further determine a patient's prescription with an aberrometer or autorefractor. These tests involve placing the patient's chin upon a machine and shining a light into his or her eyes to locate additional vision needs.
Dozens of other tests are possible during an eye exam, depending on the patient's personal eye treatment and needs. These might include evaluations for contact lenses, laser surgery, or other individual requirements. Pediatric eye exams may include further tests as well. Depending upon which tests are done, it may also be necessary for the doctor to dilate the patient's pupils using special eyedrops. Therefore, it may be helpful to bring someone along who can drive you home after the exam.
A typical eye exam last between half an hour to a full hour. This depends on the patient's needs and the number of patients the eye care specialist is treating. Arriving fifteen minutes early can be helpful, particularly when their is paperwork such as new patient forms to complete. Medical insurance information, a list of prescriptions and other medications, and a patient medical history may all be required prior to the eye exam.