In each eye, there is a crystalline lens, which has the ability to adapt for distant and near vision, enabling us to see objects clearly, whether distant or near, small or large.
As we grow older, our eye lenses begin to yellow, and the reducing transparency impairs our vision. The lens also stiffens with age, thus losing the ability of focusing on near objects. Because of this, people who had a perfect vision at a younger age might suddenly need reading glasses around the age of 45.
A cataract is a clouding of the lens inside the eye. To some extent, these changes can be considered part of normal aging and can be found in children and adults of any age. Age-related cataracts are thus more pronounced in the elderly, but usually do not interfere with the vision. Some babies are born with cataracts – in such cases, a surgery is needed as soon as possible, usually a few weeks after birth. Luckily, congenital cataracts are very rare. By definition, a cataract is any type of clouding of the lens, which means that there are many changes happening inside the eye that will not impair your vision. Because the lens ages throughout our lives, the question we need to ask ourselves is not whether we have cataracts or not, but whether they affect our vision to the extent that we cannot see clearly. A cataract needs to be surgically removed when it impairs our vision so badly that we can no longer perform our daily tasks. Whenever a patient has such problems, it is reasonable to remove the lens and replace it with an artificial one.