Aphakia is a medical condition characterized by an absence of the lens of the eye. The lens, a clear structure located beneath the iris, is used to refract and focus light so that it will hit the retina. Without a lens, someone will develop vision problems. Several techniques can be used to correct aphakia, with correction being especially important in children because their brains are still laying down the pathways which convey visual information, and interruptions in vision can lead to long term vision damage.
In some cases, aphakia is a congenital anomaly, in which case it may be diagnosed soon after birth during a routine examination of the baby. The lens may also be removed or seriously damaged as a result of infection, ulceration, or trauma. Surgeons may opt to remove the lens deliberately to treat conditions like cataracts, in which the lens becomes clouded, making it hard to see.
People with aphakia experience hyperopia, also known as farsightedness. They also suffer a loss of accommodation, meaning that their eyes have trouble adjusting and refocusing to respond to changes in distance. Accommodation tends to decline overall with age, but in people with aphakia it can be an especially big problem. As a result, people usually opt to treat the condition.
Some people can receive lens implants which will correct or partially correct the problem. In the case of a partial correction, an ophthalmologist can perform an eye examination to determine the additional level of correction needed, and write a prescription for glasses or contacts. Corrective lenses may not necessarily need to be worn all the time in someone with an implant, and they are most commonly needed for reading and close detail work.
Corrective lenses can also be worn without an implant. Either glasses or contacts can be used, although contacts are often recommended because they cause less visual distortion than glasses. For children, contacts can be preferred for this reason. Regular eye exams are also usually recommended to ensure that the vision correction is appropriate and that no other problems are developing.
Individuals who have aphakia also experience increased light sensitivity, especially to black light. For this reason, it can help to wear sunglasses and other protective eye wear in bright light, and to avoid extremely bright or blacklit conditions. Failure to observe precautions in bright environments could result in permanent damage to the retina, which will obscure vision even further.