Congenital cataract is a lens opacity that is present at birth or shortly after birth. Diagnosis is clinical and sometimes with imaging. Treatment is surgical removal of the cataract.
(See also Cataract in adults.)
Congenital cataracts occur in 4 to 24 per 10,000 people worldwide (1). These cataracts may be sporadic, or they may be caused by chromosomal abnormalities, metabolic disease (eg, galactosemia), intrauterine infection (eg, rubella), or other maternal disease during pregnancy. Congenital cataracts may also be an isolated familial anomaly that is commonly autosomal dominantly inherited.
Cataracts may be located in the inner center of the lens (nuclear) or the outer layer of the lens (cortical), or they may involve the lens material underneath the anterior or posterior lens capsule (subcapsular). They may be unilateral or bilateral. As with other cataracts, the lens opacity obscures vision.
General reference
1. Wu X, Long E, Lin H, Liu Y. Prevalence and epidemiological characteristics of congenital cataract: a systematic review and meta-analysis. Sci Rep. 2016;6:28564. Published 2016 Jun 23. doi:10.1038/srep28564
Diagnosis of Congenital Cataract
Eye examinations
Sometimes imaging
Diagnosis is suspected during routine eye examination at birth and at routine well-child visits if the red reflex is abnormal and/or the optic disc is obscured on ophthalmoscopy. Children with these findings should always be evaluated urgently by an ophthalmologist because unilateral congenital cataracts should be surgically removed within the first 4 to 6 weeks of life.
The ophthalmologist does a dilated eye examination and possibly ultrasound of the eye to confirm the diagnosis of a cataract and ensure no other structural problems affect the retina.
Treatment of Congenital Cataract
Surgical removal
Treatment of amblyopia if present
Cataracts are removed by aspirating the opacified lens material through a small incision. In many children, an intraocular lens may be implanted after 6 months of age. Postoperative visual correction with eyeglasses, contact lenses, or both is usually required to achieve the best outcome (1).
With a unilateral cataract, the quality of the image in the affected eye is inferior to that of the other eye (assuming the other eye is normal). Because the better eye is preferred, during childhood, the brain suppresses the poorer-quality image, and children may develop amblyopia (reduction in visual acuity of an eye caused by disuse during visual development). Thus, even after cataract removal, effective amblyopia therapy is necessary for the treated eye to develop normal sight. Some children are unable to attain good visual acuity because of accompanying structural defects.
In contrast, children with bilateral cataract removal, in which image quality is similar in both eyes, more frequently develop equal vision in both eyes.
Some cataracts are partial initially and opacify further during the first 10 years of life. Eyes with partial cataracts have a better visual outcome.
Treatment reference
1. Plager DA, Lynn MJ, Buckley EG, et al. Complications in the first 5 years following cataract surgery in infants with and without intraocular lens implantation in the Infant Aphakia Treatment Study. Am J Ophthalmol. 158(5):892-898, 2014. doi: 10.1016/j.ajo.2014.07.031
