Why Are Eyes Dilated at Eye Exams?

Some eye exam patients balk at the mention of dilating drops. They associate this chemical enlargement of their pupils with time delays and an hour or two of blurred vision. Looking beyond these temporary inconveniences, there are significant benefits to dilating the eyes during an exam.

Larger Viewing Area

• The retina and optic nerve as the doctor sees them.

  Doing an examination of the eye's interior through a non-dilated pupil has been likened to viewing a room through a keyhole. By dilating the pupils, the doctor's view of the back of the eye increases up to sevenfold.

Better Recognition of Ocular Disease

• The larger viewing area allows a three-dimensional inspection of the retina, optic nerve and blood vessels. This leads to easier diagnosis of eye diseases such as glaucoma, macular degeneration and diabetic retinopathy -- all major contributors to adult blindness.

Early Diagnosis of Systemic Disease

• The retina is a surprisingly good indicator of general health. A dilated inspection aids in the diagnosis of high blood pressure, diabetes, multiple sclerosis and other systemic diseases before any outward symptoms develop.

More Accurate Prescriptions

• Dilating drops also block the eye's natural ability to change focus during the exam. This eliminates a large variable and allows the doctor to produce a more accurate prescription.

The Fight Against Blindness

• Prevent Blindness America estimates that by the year 2030, there will be twice as many blind Americans as we have today. The National Glaucoma Society, the American Diabetes Association and many other health care organizations have joined the call for regular dilated eye examinations as the first line of defense against blindness.