Why do They Dilate my Eyes for an Eye Exam?

Getting regular eye exams is an important way to monitor your optical and general health. Part of a thorough eye exam is pupil dilation, which is accomplished by putting eye drops in the eye which will force your pupil to stay open, even in bright light. The procedure is not uncomfortable, but it does represent a loss of part of your day, as the drops take approximately 30 minutes to work, and you will have difficulty seeing for around an hour after your exam, until the drops have stopped working. Some patients question whether or not they need pupil dilation with every eye exam.

Pupil dilation is extremely important, because it allows the optometrist to see all the way into the back of the eye. During a normal eye exam, the optometrist will use a bright light and a lens to look into the eye, inspecting the health of the cornea, iris, and lens of the eye. However, the bright light causes the pupil to contract, making it difficult for the optometrist to see the back of the eye. When the regular eye exam is done, the optometrist will dilate your pupils so that he or she can completely check your optical health.

The back of the eye hosts the retina, optic nerve, and important blood vessels. When your pupils are open, the optometrist will be able to clearly see these parts of the eye and evaluate them. The procedure can reveal general health problems like hypertension, and can also catch the signs of glaucoma and cataracts early. For these reasons, optometrists ask their patients to submit to the procedure with every eye exam, despite the inconvenience, because they would rather catch serious medical problems early.

Healthy adults should have an eye exam, along with pupil dilation, every one to two years, or more frequently as recommended by an optometrist. People who are at high risk for developing optical conditions may need to have their eyes examined more frequently. In any case, remember to bring a pair of sunglasses along to your eye exam, so the bright light outside will not hurt your eyes after the examination. The optometrist’s office will usually have several pairs of disposable sunglasses as well, just in case you forget. Because you may feel disoriented after pupil dilation, you may also want to consider asking someone else to drive you to your eye appointment, or accompany you on public transportation.