Blepharoptosis following pterigium excision is a rare complication, and there is no published report on its etiology, incidence, and surgical pathology. We report 4 cases of persistant blepharoptosis following pterigium surgery. The main clinical features are high or absent upper lid crease, thinning of ptotic eyelid above tarsal plate, good levator function, 2-3mm of ptosis degree, abnormal drooping of upper eyelid at downward gaze, and deepening of the upper sulcus. They have a specific anatomic defect in the aponeurosis of levator palpebrae superioris(LPS) muscle. It has been assumed that eyelid speculum leads to injury of upper border of tarsal plate and disinsertion of aponeurosis of LPS muscle in the patient who had vulnerable aponeurosis of LPS muscle during surgery.
Disinsertion of aponeurosis of LPS muscle from its epitarsal attachment was discovered during blepharotosis surgery and it was repaired anatomically to correct the blepharoptosis.