Ptosis is a drooping of the upper eyelid. The lid may droop only slightly, or it may cover the pupil entirely. In some cases, ptosis can restrict and even block normal vision. It can be present in children as well as adults and may be treated with surgery.

What problems can result from ptosis in children
The most serious problem associated with childhood ptosis is amblyopia (lazy eye), which is poor vision in an eye that did not develop normal sight during early childhood. This can occur if the lid is drooping severely enough to block the child's vision. More frequently, amblyopia can develop because ptosis tends to lead to constant blurriness of visual images, causing astigmatism. Ptosis can also hide misaligned or crossed eyes, which can cause amblyopia.