Pupil dilation ( making the pupil larger) is extremely important because it allows Dr. King to see all the way into the back of the eye. During a normal exam, the doctor 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 or get smaller, making it difficult to see the back of the eye. The drops are necessary to open the pupils for a wider view of the retina, optic nerve and important blood vessels. The dilation is not only an important tool in diagnosing and documenting a multitude of eye diseases, but it can also reveal general health problems like hypertension, diabetes, and high cholesterol. Dilation is considered part of the eye exam and is not billed separately.