Congenital Cataract

What is a cataract?

The natural crystaline lens behind the pupil is largely responsible for focusing images onto the retina (tissue in the back of the eye). The natural lens should be clear and transparent. When this lens becomes cloudy it is called a cataract.  This will cause permanent visual loss if it is not treated timely in children.

What causes cataract in children?

In adults, the cataract is caused by the lens aging however the exact mechanism for development of congenital cataract in children is unknown. Many maternal infectious diseases, such as toxoplasmosis, herpes simplex, rubella during pregnancy are associated to the development of congenital cataract. Some cataracts are familial therefore likely to be genetic. Rarely, cataract can be associated with other systemic diseases such as Marfan Syndrome, homocysteinuria or chronic use of steroids.

How is cataract diagnosed in children?

The most common sign of congenital cataract is a poor “red reflex” in the child’s pupil. All newborns should undergo “red reflex” screening by their midwives or GP for early detection and diagnosis.  This is especially important for those newborns with a family history of congenital cataract.

How is cataract treated in children?

Not all congenital cataract requires surgical removal and only those visually significant cataracts need prompt surgical treatment.  The decision of whether a child needs cataract surgery or not, is best made by an ophthalmologist experienced in cataract surgery (preferably a paediatric ophthalmologist).

Cataract surgery in children is much more complex than adult cataract surgery due to the smaller eye and rarity of this condition.  It involves removal of the cloudy lens, followed by either contact lens wear or primary intraocular lens implantation during surgery.  Intraocular lens implantation is routinely used for those children 12 months or older however some surgeons feel comfortable to implant children as young as six months old if contact lens wear is difficult.

Will my child have perfect vision after cataract surgery?

Children with congenital cataract often have some visual deprivation due to early onset cataract, which invariably causes deprivation amblyopia. Postoperative refractive correction by contact lens, glasses, or intraocular lens implantation plays very important part in the visual rehabilitation. Treatment of amblyopia is as important as cataract surgery for a successful visual outcome. Bilateral cataracts (both eyes), if operated on early, often has a better visual prognosis than unilateral (one eye) cataract in children.

What is the best time for cataract surgery in children?

Generally speaking, congenital cataract should be operated as early as possible if judged visually significant. However there is growing evidence cataract surgery earlier than four weeks of age is associated with a higher risk of the development of glaucoma.  Therefore the best time for surgery is around six-eight weeks of age.

Educational Implications

Behaviours or conditions that might indicate congenital cataracts

• Poor visual acuity.
• White, or poor pupil red reflex.
• Photophobia.
• Progressive deteriorating of vision.
• Learner may be challenged visually when going from indoors to outside.
• Reduced colour discrimination.
• Increased sensitivity to glare.
• Blurred vision.

What to do

• The young person should visit an ophthalmologist to determine diagnosis and treatment.
• Long term visual rehabilitation is required for amblyopia treatment.
• Allow time for adaptation to light change.
• Support the wearing of any prescribed lenses.
• Materials may need to be enlarged.
• May need to use sunglasses, visors, or hats outdoors and indoors as well.
• May require reduced or diffused lighting.
• Lighting from behind can be useful.
• Magnification tools may be needed.