The Eye Exam: Why it's Necessary & What to Expect
Q: Why is it important to get an eye exam if your vision seems normal?
A: We recommend that children get their first comprehensive eye exam when starting school, even if they are not experiencing symptoms and don't show any outward signs of not seeing well. A child may not complain about poor vision, but at such a young age they may not realize that they're not seeing well at a distance or up close, or that their eyes are not working well together.
Sometimes I'll see a patient who has come in for his first eye exam at the age of 35, and one eye is completely nonfunctional due to untreated amblyopia, an eye disorder that prevents vision from developing properly during early childhood.
This is an example of why it is imperative to begin getting comprehensive eye exams as a young child and continue all the way up through school and into adulthood, even if you are not experiencing adverse visual symptoms. Another example is a person who has glaucoma. Glaucoma may have no symptoms until sight is already lost. It can be diagnosed in its manageable stages only through a comprehensive eye exam.
Anyone who begins to experience challenges with their vision, whether on the computer, reading a book or seeing street signs as they're driving, should go in for an eye exam. An adult without a vision problem should get a comprehensive eye exam every two years whether or not he or she has any visual symptoms. Adults who wear glasses or contact lenses or have an eye disorder should have an exam annually.
A patient who has a systemic problem that can affect the eyes, such as diabetes, inflammatory disease or even uncontrolled hypertension, should have an eye exam every year. Sometimes diabetics need to have their eyes checked more often than once a year, maybe two or three times annually, depending on their ability to control their blood sugar levels.
Q: What types of testing does a comprehensive eye exam include?
A: A comprehensive eye exam is made up of many different tests. The first step is taking a very good case history: determining what the chief complaint is—why that patient is in for an eye exam. Next we do entrance tests on the patient, which consist of visual acuity measurements. These involve having the patient read letters from an eye chart on the wall (for distance vision) and sentences from a hand-held sheet (for close vision), both with and without glasses or contact lenses.
We would then go into the objective portion of the eye exam, when the eye care professional takes measurements that are not reliant on the patient's responses. For example, we examine the retina, eye muscle movements, pupils, eye motility and any eye turns.
Then the doctor will examine the health of the patient's eye. This is performed using a biomicroscope, an apparatus with lenses and very bright lights that the doctor looks through in order to see the front, middle and back of the eye. If necessary, the doctor may instill drops into the patient's eye to dilate the pupils, which allows the eye care professional to further evaluate not only the central part of the retina but also the peripheral area.
Finally, the doctor will offer an assessment and a plan based on his or her findings. For example, it may be necessary for that patient to wear glasses, or to come back for some follow-up testing and care. Maybe the doctor saw early signs of glaucoma or macular degeneration or cataracts. This is an opportune time for the doctor to educate the patient on his or her findings and what course of action will be taken.