Contact lenses are the number one cause of ocular emergencies, and the improper use of contact lenses can cause permanent damage to the eyes and vision. A recent study revealed that individuals who wear contacts on a daily basis are four times more likely than a non-contact lens wearer to suffer a vision- threatening eye infection. Those who sleep in their contacts are 20 times more likely! For this reason, Dr Eddington highly discourages the practice of extended wear, or sleeping in contact lenses. In addition, because many ocular diseases don't cause vision problems until late stage, we recommend a routine exam annually.