This is the medical term for drooping of the upper eyelid. It can occur on one side (unilateral) or both upper eyelids (bilateral). Ptosis occurs when the muscles that raise the eyelid are not strong enough to keep the eyelid up in proper position. There are two muscles that elevate the eyelid, superior levator muscle and Muller’s muscle. The superior levator muscle is the dominant muscle that lifts the eyelid. Its tendon attaches to the tarsal plate in the eyelid in order to lift the eyelid.
This the most common cause of ptosis of the upper eyelid. The muscles that keep the eyelid in position gradually become weaker and let the upper eyelid droop. Also the levator aponeuronsis (muscle tendon) can slip and loose its attachment to the eyelid and let the eyelid droop. Sometimes eye surgery such as cataract surgery can make this condition worse.
This form is hereditary and needs early attention if the lids are so low that it is obstructing the child’s vision. This could lead to lazy eye or amblyopia.
Lacerations, burns and chemical injuries can lead to drooping of the eyelids.
Brain tumors, brain aneurysms, Horner’s Syndrome and third cranial nerve problems can cause ptosis.
Myasthenia gravis, tumors, edema or swelling and other muscle diseases.
Treatment is surgical if the ptosis is interfering with the person’s vision. The goal is to raise the eyelid to the proper height and match the other side if it is unilateral. The side effect to be avoided is not to over correct the eyelid keeping the eyelid from closing completely. This could result in a dry eye syndrome. There are different surgical approaches depending on the cause and severity of the ptosis. The possible surgical procedures are levator resection, reattaching the levator aponeuronsis, Muller muscle resection, and frontalis sling.