Definition: Presbyopia is the aging-associated loss of the ability of the eye to focus on near objects. Similar to the “zoom” on a camera, the young eye has the ability to accommodate, or change its focus from far to near objects and visa versa. This accommodative ability slowly declines with age.
Cause: The cause of presbyopia is unknown, but is thought to be due to a progressive hardening of the lens of the eye with age. This progressive hardening makes the lens less able to change its shape and increase its near focusing power.
Symptoms: Presbyopia results in decreased ability to see up close. A person may notice that they have to hold newspapers farther away from their eyes than they used to in order to see them clearly. The onset of presbyopia is typically in the mid to late 40s. For people who are hyperopic, symptoms may occur as early as the late 30s.
Prognosis: Near vision slowly decreases with presbyopia until age 65 to 70, when all near focusing power of the eye is lost. Eventually, most patients require a different lens prescription for distance, intermediate vision (computer screen) and near vision (reading). It is a benign condition, however, and does not cause loss of vision other than the need to use near vision glasses. Excellent distance vision can be maintained, even with presbyopia.
