The many delicate parts of the eye that must work together to create vision are nothing short of amazing. First, light enters the cornea, where rays are bent so they can freely pass through the pupil in the center of the iris.
The iris itself is like the shutter in a camera. It shrinks or expands to accommodate the amount of light entering the eye. Once it’s through the iris, light rays finally pass through the eye’s lens.
The lens is a clear structure that widens or narrows itself to focus incoming light rays properly. Once light has pierced the lens, it travels through a gel-like substance called vitreous to reach the retina. Finally, the optic nerve communicates with the brain to turn light rays into the images we call vision.
For sighted people, all of this happens literally at the speed of light and continues every moment their eyes are open.
Many things can go wrong during this process that can affect a person’s ability to see clearly. One of these problems is called aphakia. Aphakia is a condition that describes the absence of the lens of the eye.
Types and Causes of Aphakia
There are three main causes of aphakia. It can be caused by genetics, cataracts, or trauma.
1. Genetic Aphakia
Genetic aphakia is a rare disorder that causes babies to be born without lenses or with damaged lenses. There are two types of genetic aphakia.
Primary aphakia describes a complete absence of eye lenses caused by genetic mutation or developmental issues.
Secondary aphakia results in lenses that have become detached before birth or lenses that were absorbed by the eye in utero. Secondary aphakia is associated with viral exposure.
Cataracts occur when proteins clump together on the lens, making it cloudy or milky. Surgical removal of the defective lens can improve vision for some people.
The National Library of Medicine estimates that around 5% of all people with cataracts have aphakia.
Severe injury to the eye or head can push the lens out of place, causing it to become dislocated or so damaged that it requires removal.
Symptoms of Aphakia
People with aphakia can still see, but their vision is usually impaired in some way. One of the most common symptoms is long-sightedness or hyperopia. Long-sightedness does not mean that a person is able to see a long way. People with hyperopia have difficulty seeing close-up items like a phone screen or printing on a page.
Other symptoms include:
- Blurred vision
- Trouble focusing on individual objects
- Loss of accommodation or an inability to maintain focus as an object moves farther or closer
- Erythropsia, in which objects appear to have a red tint
- Cyanopsia, in which objects appear to have a blue tint
- Colors appearing to be faded or unusually intense
The symptoms of surgically induced aphakia can be temporary and a normal part of the recovery process.
How is Aphakia Diagnosed?
Your eye doctor can diagnose aphakia by looking at your medical history and conducting a physical examination. Signs that indicate a missing lens include:
- Scarring on the black ring around the iris (known as the limbal ring)
- Iridodonesis or “jiggling” of the iris
- Hypermetropic fundus or a shortening of the fundus or interior of the eye
If you’re experiencing the symptoms of aphakia, an examination by a qualified ophthalmologist can confirm the diagnosis. After the cause of your vision problems is identified, your doctor will prescribe a treatment.
Treatments for Aphakia
There are several treatments that can improve the vision of those with aphakia. Glasses or contacts are the most common options. Aphakic glasses, which are thick and used to magnify images at a high level, can only be used by people who have aphakia in both eyes. Other disadvantages to aphakic glasses include a decrease in field of vision and unflattering aesthetics.
For adults, surgery involves removing the damaged lens and replacing it with an artificial one. The procedure is safe and surprisingly simple. It can typically be performed with local anesthetic and takes less than an hour to complete. Your eye doctor may prescribe glasses or contact lenses to further improve your vision after surgery.
The American Academy of Pediatrics recommends that babies with aphakia receive surgery at around four weeks old. They’ll also need to wear special contact lenses or glasses for a long time after surgery, even while they are sleeping. At about one year old, most children will be ready to undergo the surgery to implant an artificial lens.
Frequently Asked Questions About Aphakia
Can Aphakia Surgery Cause Complications?
All surgeries pose a risk of complications, but artificial lens implants are considered to be safe with a very low risk for unwanted side effects. Some possible complications include:
- Aphakic glaucoma or pressure inside the eye
- Retinal detachment
- Vitreous detachment
These complications are easily addressed through surgery or other non-invasive treatments.
What is the Long-Term Prognosis for Aphakia?
If there are no other complications, prognosis is generally good for most adults. While people with aphakia may never see as well as fully sighted people, treatments can result in great improvement.
In order for children to have a positive outcome, they must have frequent appointments and adjustments to their corrective lenses to keep up with the normal changes in their growing eyes.
What Else Can I Do to Protect My Vision with Aphakia?
There are several steps you can take to make living with aphakia easier. These include:
- Wearing your prescribed corrected lenses as your doctor recommends
- Wearing sunglasses and a hat to protect your eyes from strong light
- Avoid facing light directly
- Using a magnifier to prevent strain when viewing things up close
Avoiding eye strain is always an important part of protecting eye health, but it is especially important for those with aphakia.
My First Child Was Born with Aphakia. Does that Mean All of My Children Will Have This Condition?
Genetic aphakia is very rare. Consult a specialist to discuss the chances of genetic aphakia affecting more than one child. The answers depend, in part, on which type of genetic aphakia caused the disorder.
Living With Aphakia
If you or someone you know is experiencing the symptoms of aphakia, call your ophthalmologist as soon as possible. Early and consistent treatment of this disorder can improve both the vision and quality of life for a person with aphakia.
- Congenital primary aphakia | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program (nih.gov)
- Prevalence of cataract and pseudophakia/aphakia among adults in the United States – PubMed (nih.gov)
- Aphakia in Adults and Children (eyehealthweb.com)
- Long sightedness (hyperopia)Look After Your Eyes
- Cataracts – HealthyChildren.org