Aphakia means not having a lens inside your eye. The lens is the clear, oval-shaped structure behind the iris (colored part of your eye) and pupil. It focuses light rays on the retina. Without a lens, the eye is out of focus and vision is blurry.
What causes aphakia?
Cataract surgery. A cataract is clouding of the eye’s natural lens. With surgery, the cataract is removed. Typically, it is replaced with an artificial lens (IOL or intraocular lens). Many infants and some older children are left without an IOL after the cloudy lens is removed.
Injury. The lens can be damaged or lost due to eye trauma.
Congenital defect. Very rarely babies are born without lenses. Others are born with detached or abnormal lenses.
Symptoms
The main symptom of aphakia is blurred vision, but it also affects:
Close-up vision. Those with aphakia are very farsighted or can’t see well close-up, as this requires a lens. But distance vision is also affected.
Accommodation. The eyes lose their ability to “accommodate” or change focus between distances.
Color perception. Colors may appear faded.
Aphakia can also cause iridodenesis or a “jiggly” iris. Without a lens or IOL behind it, the iris jiggles or trembles as you move your eyes.
Diagnosis
Aphakia in adults and older children. An ophthalmologist uses a bright light and microscope (slit lamp) to detect aphakia during a comprehensive eye exam.
Congenital. For unborn babies, aphakia may be detected with ultrasound in some cases.
Treatment
Surgery. Aphakia is usually treated with surgery. An IOL replaces the damaged, detached or missing lens. With newborns, the IOL is implanted at a subsequent surgery. This is because a newborn’s eye is at higher risk for complications with an IOL placement.
Contacts lenses. Special contact lenses can help provide clear vision in babies too young for an IOL replacement lens. These are worn for a month or more without changing. Adults can also wear aphakic contact lenses.
Glasses can treat aphakia but work best when both eyes are without lenses. They are not used as often as in the past because the lenses are very thick and heavy and contacts are available.
Babies and children with aphakia need treatment as soon as possible. Without treatment, aphakia can lead to amblyopia, which may be irreversible. This is when the brain loses its connection with the eye and vision is “turned off.”