Changes in eyesight often develop gradually, so people may not notice them right away. An eye exam provides a structured way to evaluate how well the eyes see and how the different parts of the eye appear. Some people schedule eye exams after noticing blurry vision or eye strain, while others visit on a routine basis.
What Are Eye Exams?
Eye exams are a series of tests that evaluate vision and the overall condition of the eyes. An eye care professional, such as an ophthalmologist, uses charts and specialized instruments to assess how clearly a person sees at different distances. The provider also examines structures of the eye, and this can include the eyelids, cornea, lens, retina, and optic nerve.
Eye exams generally fall into two categories. A vision screening is a brief check that measures visual sharpness, and it can be conducted at schools or during a general physical. A comprehensive eye exam takes place in an eye care office. It includes multiple tests that look at eye health in addition to visual clarity. People who wear contact lenses may also receive a contact lens exam, which includes measurements of the eye’s surface to determine lens size and fit.
What Are They For?
A common purpose of an eye exam is determining whether a person needs corrective lenses. The results may indicate nearsightedness, farsightedness, astigmatism, or presbyopia, which is age-related difficulty focusing on close objects. The provider can write a prescription for eyeglasses or contact lenses. Vision changes over time, so existing prescriptions may also be updated. Eye exams also give providers an opportunity to observe changes in eye health. Some eye conditions, such as glaucoma, may not produce noticeable symptoms in their early stages.
What Does It Involve?
Specific tests vary, but many appointments follow a similar sequence. The visit can begin with questions about overall health, including current medications, vision concerns, and family history. This information gives the provider context for the tests that follow. Patients may then read letters from a chart placed at a set distance. This test measures how sharply each eye sees. The provider then uses a device to switch between lenses while the patient indicates which option looks clearest. These results help determine the lens prescription.
Tonometry measures the fluid pressure inside the eye. Providers often use a gentle puff of air for this test, or they can use a brief touch to the eye’s surface after numbing drops are applied. Providers may apply drops that widen the pupils. Dilation allows a fuller view of the retina and optic nerve. The effects can last several hours. The provider may review the findings and explain any recommended next steps after testing, such as a new prescription or a follow-up visit.
Schedule an Exam
How often a person should have an eye exam can depend on certain factors, such as age, current vision, and personal or family health history. Bringing current eyeglasses, contact lenses, and a list of medications to the appointment may help the provider make accurate comparisons. Dilation temporarily affects vision, so patients can bring sunglasses and arrange transportation home. Contact an eye care provider to schedule a comprehensive eye exam.
