What Is Presbyopia?
With time, the crystalline lens loses its elasticity and ability to focus images seen up close. Individuals in their forties often note a gradual reduction in the ability to focus when reading. They are forced to read at a farther-than-normal distance. This phenomenon, known as presbyopia, is an unavoidable side-effect of aging.
Common symptoms of presbyopia are:
- Blurred near vision.
- Visual fatigue.
- Difficulty in working for a long time on something up close.
A reduction in the range of near vision appears around the age of 45 and can be corrected with convex lenses, which should only be worn when viewing something up close. Around the age of 55 to 60, vision at distances of a few metres also becomes blurred, and a double corrective is required (bifocal or variable focus lenses). Flexible bifocal contact lenses for correcting presbyopia are available.