Mechanism of upper lid ptosis in the anophthalmic orbit.

The occurrence of upper lid ptosis in 66 patients in the anophthalmic state was 18 percent, despite an adequate prosthesis. The commonly cited causes for this entity do not hold up under examination. A detailed review of the anatomy of the levator mechanism and of the anatomy of an enucleation suggests that the etiology is really based on the production of a mechanical imbalance in the levator apparatus. Suggestions for management and for the timing of the correction (in relation to other surgical procedures) are made.