Lid retraction and levator aponeurosis defects in Graves' eye disease.

Vertical palpebral fissure determinants and lid crease height were measured in patients with Graves' eye disease (GED) and in normal subjects. The fissure and crease height are positively correlated with exophthalmometer readings in each group. Compensatory levator aponeurosis defects are shown to occur in patients with GED. These, along with the effect of exophthalmos on the lower lid position, the observation that the lower lid is closer to the inferior limbus than the upper lid is to the superior limbus in normal subjects, and the effect of contracture of the inferior rectus on the lower lid position, explain why inferior scleral show is found to be greater than superior scleral show in patients with GED. Thus, lid retractor surgery in GED patients should be performed only after the palpebral fissure, levator function, and lid crease height stabilize, and after any contemplated surgery that would alter the exophthalmos and extraocular muscles has been performed.