What is a Congenital Cataract?
When we are born, most of us have crystal-clear lenses in our eyes. This allows light to stream through the cornea at the front of the eye and refract unimpeded onto the retina at the back of the eye. However, 0.03 to 0.04 percent of babies are born with cataracts in the UK. A cataract is a condition where the crystalline lens inside the eye is cloudy. This varies in severity and how much it will impede normal vision.
The Causes of Congenital Cataracts
Cataracts in general are usually caused by the aging process, with the natural lens dulling and clouding over time. Cataracts present at birth, however, are caused by exposure to various viruses, certain medications and other conditions present in either the child or the mother. Most cases of congenital cataracts can be traced back to:
- Use of tetracycline antibiotics. This drug class is also responsible for permanently staining teeth and isn't usually recommended for pregnant women or babies.
- Measles or rubella infection in the mother during pregnancy. Other infections such as chicken pox, herpes simplex or zoster, and even syphilis can cause congenital cataracts.
- In pediatric cataracts, blunt force trauma to the eye is responsible for the cataract in up to 40% of cases.
- Some cases are inherited or present for no apparent reason. It isn't necessary to know why the condition has occurred to treat it properly.
Types of Congenital Cataracts
There are four primary types of congenital cataracts that have different suggested treatments and impacts on vision. Understanding the different types is imperative to understanding the recommended treatment plan.
Nuclear cataracts appear in the center of the crystalline lens of the eyes. They are the most common type of congenital and pediatric cataracts and only require immediate surgery if vision is badly obscured.
Cerulean cataracts are easy for even a layman to see, as they are characterized by a blue spot on the eye. They are usually small and can be corrected at a later age as they usually don't interfere much with vision.
Anterior polar cataracts are found on the front of the eye and are usually inherited. They are usually small and don't interfere with vision much, leaving them to be corrected at a later age at the parents' convenience.
Posterior polar cataracts appear in the back of the lens and usually well-defined.
Timing Considerations for Surgical Correction
If your child's optometrist or ophthalmologist believes surgery is necessary for your infant, there are some considerations that need to be weighed before moving forward. Concerns about increasing intraocular pressure (IOP) that can lead to secondary glaucoma are always valid. Our eyes are filled with fluids, and changing those fluid levels can lead to an increase in pressure. There are also concerns about anesthetizing an infant, as it is riskier and more difficult than anesthetizing a child.
With those concerns in mind, correcting serious cataracts in infants is important to allow vision to grow with the child. If surgery is delayed too long, the child's vision could be impacted permanently because the relationship between the eyes and the brain is solidified in early childhood. Some experts say the optimal time to intervene and remove a visually significant congenital cataract from an infant's eye is between the ages of 6 weeks and 10 weeks. Several studies suggested that delaying cataract surgery in infants increases the risk of developing resistance to amblyopia treatment and decreases potential visual functions
Talk to your surgeon about when he or she recommends surgical correction. His or her recommendation will tell you a lot about the state of your child's vision and the proposed treatment process.
Replacement Corrective Lenses
After the cataract is removed, the eye will lack a natural crystalline lens. This makes the vision in the surgical eye unacceptable, so it must be corrected by other means to provide clear, crisp vision. There are three primary options for correcting vision after cataract removal:
- An intraocular lens. This is the most common solution in adults, but opinions are divided about their use in children. While it is possible to switch out an intraocular lens if the child's vision needs to change later in life, there will be an added risk of revision surgery. For this reason, some surgeons recommend using another method of correction.
- Contact lenses. Contact lenses can be used in children as young as a few months, as they are soft and pliable. Parents and caregivers can learn to insert and remove the lenses quickly and easily, which is even easier when the child is asleep.
- Glasses. Babies and toddlers can be fitted with corrective lenses at almost any age, if they are needed. No one is 'too young' for glasses.
Congenital cataracts are not very common, but they can be concerning when they're diagnosed. Luckily, there are plenty of corrective options to give your baby clear, crisp vision. If you are concerned about something you're seeing in your baby's eye, have it evaluated right away. While extremely rare, some ocular cancers are visible to others. By having the condition diagnosed properly, you will then be able to work on a plan of treatment with your baby's pediatrician and ocular specialist.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 2 Nov 2016, Last modified: 2 Oct 2023