Congenital ptosis is the most common cause of ptosis in children. It is due to an abnormal development of the levator muscle of the eyelid. As a result, the upper lid is droopy, covering part of if not the entire cornea, and the upper lid crease is absent. Due to the close embryological development of the levator muscle and the superior rectus muscle, it is not surprising to see an associated difficulty in elevating the eyeball in patients with congenital ptosis. There is also lid lag on downgaze. It is commonly unilateral, but bilateral cases can also be seen. There is no well-defined pattern of heredity. Ocular myasthenia gravis should be ruled out when ptosis is intermittent or when it is noticeably worse at the end of the day.
When unilateral, ptosis in children can produce dense amblyopia, due to the eyelid blocking the visual axis or inducing astigmatism on the affected eye. Even mild ptosis can induce astigmatism and cause secondary amblyopia. It is not uncommon to see an abnormal head posture such as chin elevation to compensate for the droopy eyelid and to obtain binocular fusion.
Children with congenital ptosis need to be seen by a pediatric ophthalmologist for an evaluation of their visual potential. These children need to be refracted and given glasses if a significant amount of astigmatism is present. Then, amblyopia treatment should be started as soon as the refractive correction is given. The droopy eyelid should be suspended by any skin tape during wakeful hours.
Ptosis surgery is ideally done at age 5, when the facial bone structure is well-defined. There are several choices in terms of frontalis sling material for this surgery. Patients should be primed about the resultant lagophthalmos (inability to completely close the eye) after ptosis repair.