Explanation:The insertion of an intraocular lens (IOL) is a routine part of cataract surgery in adults, even in many developing countries. It is now over fifty years since the first IOL was implanted. However, until recently, IOLs were not widely used in children.
As evidence for the long-term safety of IOLs in adults accumulates, there is a growing willingness to use IOLs in children. Provided the zonule is stable and the eye is not inflamed, IOL implantation is already routine in children over five years old, and increasingly in children between two and five years. The use of IOLs in children under two years remains very controversial. One reason for this is that the eye changes very rapidly in young children. In a three month old baby, an IOL power of 28-30D may be required for emmetropia. However, this will lead to significant myopia in later life. Unlike a spectacle lens or contact lens, it is not simple to change the power of an IOL. Secondly, the diameter of the lens in an infant is 2mm less than an adult lens. This makes it difficult to implant a standard adult IOL into the capsular bag. The maximum diameter of the IOL should not exceed 12 mm. Smaller IOLs designed for use in children can be obtained. The lens should be placed in the capsular bag to reduce intraocular inflammation and the risk of complications such as aphakic glaucoma.