Lower eyelid retraction, like lower lid ectropion, is caused by a compromised support system but also by the shrinkage of any of several tissue layers (skin, muscle, retractors). This combination of horizontal stretchiness and vertical shortening causes the lower lid to pull downward (retraction) below the cornea, thereby exposing the white of the eye (scleral show).
Lid retraction can occur naturally, with aging, with thyroid disease, or as a consequence of overdone transcutaneous cosmetic blepharoplasty surgery (as shown in the photos below).
There is no one all-inclusive approach to the correction of lower eyelid retraction, and not all cases can be remedied. Each operation must be highly individualized using techniques such as:
support system reinforcement (canthoplasty)
grafting of an internal spacer (Alloderm, ear cartilage, hard palate)
skin grafting
SOOF or midface lift
augmentation of insufficient bony support below the eye
newer techniques still under development
Lid retraction associated with thyroid disease is related to the pull of overactive eyelid muscles; corrective techniques are directed at lessening their pull.