Cataract in Children
Cataract is defined as an opacity in the crystalline lens or its capsule, which in turn causes a drop in vision.
While majority of cataracts occur in the middle aged or elderly, pediatric cataracts are also seen quite frequently. The incidence of congenital cataract is approximately 1 in 5000 births.
Congenital (present at birth) cataracts occur when the lens didn’t form properly. Acquired cataracts are caused by abnormal interactions among the proteins that make up the lens, which, over time, cause clumping, specks, opacities and/or cloudy areas to form.
About 25 percent of the time, congenital cataracts have a genetic cause, and may accompany a metabolic, hormonal or chromosomal abnormality (e.g., Down syndrome). Another 25 percent of the time, cataracts are hereditary, which means that the child’s mom or dad also had a cataract in childhood.
Often cataracts are idiopathic – meaning they occur for no identifiable reason.
While each child may experience symptoms differently, things to look out for are reduced vision, frequent falls or clumsiness, disinterest in visual activities like reading or watching TV, or in younger babies there could be an involuntary eye movement or squinting.
If your child is too young to complain about vision problems, you might notice a white pupil if you shine a flashlight into her eye.
Most babies are looking around and tracking things with their eyes nicely by the time they’re 3 or 4 months old. If you get the sense that your baby isn’t seeing and responding appropriately, that may be a tip off that something is wrong. Jiggling eye movements may also be a sign of a cataract or other eye problem.
Strabismus, or misaligned eyes (eyes that are not looking in the same direction), usually aren’t a sign of cataracts – most often, they’re just the result of a newborn’s poor coordination. However, sometimes strabismus occurs if there is a cataract in just one eye.
These cases are picked up by an alert parent who notices that the child cannot see very well or that there is a preferential gaze which the child adopts always. Sometimes they are picked up on routine screening in school or a regular visit for refraction.
There are three important parts in the management of the child with a cataract: Preoperative evaluation, surgery, and visual rehabilitation.
A complete preoperative evaluation of both eyes is required. Some cataracts are unilateral and the health of the apparently normal eye requires careful evaluation as well. An eye with a cataract may have other associated abnormalities which require assessment preoperatively in order to provide the most reasonable expectation for visual outcome. An ultrasound (sound waves), used to image the inside structure of the eyes, is needed in some cases.
Surgery is the mainstay of treatment. The treatment is cataract extraction with intra ocular lens implantation. This may be combined with vitrectomy in some cases.
Problems?
Since the child eye is still growing the estimation of the exact lens power to be implanted is difficult to determine. The lens implantation in children requires a compromise that accounts for the age of the child and the target post operative refraction. However these children will become more myopic over the years and eventually may need a secondary procedure sometime in future to correct the resultant refractive error.
Unlike adults, cataract surgery in children requires general anesthesia. The post operative care involves wearing spectacles and also patching the eye in some cases.
The deal with congenital cataract is that the approach to each case is tailor made to suit that patient best.
Regular follow up is essential to the successful recovery of a patient.
Despite adequate optical rehabilitation and patching therapy, misalignment of the eyes (strabismus) often develops. This may require eye muscle surgery to improve the alignment.Periodic evaluations are required to detect any other post-operative complications (for example, secondary cataract, inflammation, glaucoma, retinal detachment). A child who has undergone cataract surgery requires close monitoring of visual development and will need changes in glasses or contact lenses as the eye matures. The parents must accept the responsibility for the optical rehabilitation, patching therapy, and continued follow-up care that is required to maximize the visual development in the operated eye. Without the participation of parents, optimal vision will not be realized.
Good visual outcome after surgery depends on many factors, including patients age, type of cataract and timing of surgery. A strong post operative visual rehabilitation program to prevent amblyopia.
Amblyopia Management:
This should begin immediately in the post operative period. Corrective glasses or contact lenses and patching of the better eye is needed and decided on an case to case basis.
Overall, the visual outcome for children with cataracts is much more optimistic now than it was a few years ago. However, some eyes will have associated abnormalities, which limit the visual potential that can be obtained, despite early surgery and adequate visual rehabilitation.