The lens can be partially or completely opaque at birth. Congenital cataract is often inherited and can be seen appearing in a dominant manner together with a number of other congenital abnormalities elsewhere in the body. The condition might also be acquired in utero, the best known example of this being the cataract caused by rubella infection during the first trimester of pregnancy: remember the triad of congenital heart disease, cataract and deafness in this respect. Minor degrees of congenital cataract are sometimes seen as an incidental finding in an otherwise normal and symptom-less eye. The nature of the cataract usually helps with the diagnosis. The lens fibres are laid down from the outside of the lens throughout life. If the opaque lens fibres are laid down in utero, this opaque region can remain in the centre of the lens. Only when the cataract is thick does it present as a white appearance in the pupil and often it is difficult to detect it. It is important to examine the red reflex and see whether the darker opaque lens fibres show up. The surgeon has to decide whether the vision of the child has been significantly affected and unless the cataracts are dense it might be better to wait until the school years approach in order to obtain a more accurate measure of the vision. Sometimes the vision can turn out to be surprisingly good with apparently dense cataracts. The surgical technique is similar to that for cataract surgery in the adult. Before the introduction of lens implants, the risk of developing a retinal detachment in later life was high in these patients. When the cataract is unilateral, this presents a special case because the affected eye tends to be amblyopic, thus preventing a useful surgical result.
Was this article helpful?