A curved window called the cornea first focusses the light. The light then passes through a hole called the pupil. A circle of muscle called the iris surrounds the pupil. The iris is the coloured part of the eye. The light is then focussed on the back of the eye by the lens. Tiny light sensitive cells (photoreceptors) cover the back of the eye. The covering of photoreceptors at the back of the eye forms a thin film called the retina. Photoreceptors collect information about the images you see. Each photoreceptor sends its signals down very fine wires to the brain. The wires going from each eye to the brain are called the optic nerves. The information then travels to many different ‘vision parts’ of the brain. All parts of the brain and eye need to be present and working for us to see normally.
A cataract is a condition in which the normally clear lens of the eye becomes cloudy. This scatters the light and prevents clear images from reaching the retina at the back of the eye, resulting in reduced vision and glare. Cataracts can develop in one eye (unilateral) or both eyes (bilateral).
A congenital cataract is cloudiness in the lens of the eye that is present at birth or develops shortly after birth. About 2-3 babies in 10,000 are affected by congenital cataract.
There are many different causes of cataracts in children. Sometimes it is not possible to determine exactly why the cataract has occurred. The most common causes are -
Cataracts can affect the vision in different ways depending on age and the severity and location of the cataract.
If the cataract is mild, your Childs vision may not be affected, and the Doctor may decide that early or immediate surgery is not required. Your child will be prescribed glasses if necessary and will be reviewed frequently to ensure that his/her vision is developing normally. If the mild cataract is present in one eye only, you may be asked to patch your Childs other eye to prevent the eye with the cataract becoming lazy (amblyopic).
If a severe bilateral or unilateral cataract is present the child may develop lazy eyes if surgery is not carried out within the first 3 months of life. The specialised ‘vision part’ of the brain develops very rapidly over the first few months of life. If a clear, sharp picture is prevented because severe cataracts are present during this critical period the brain will not develop the ability to see clearly.
The Ophthalmologist will assess your child’s cataract and discuss the most appropriate form of treatment with you during your appointment.