Orbicularis Paresis After Fat Transposition for Tear Trough Deformity.

Orbital fat transposition, used to manage tear trough deformity, involves mobilizing orbital fat over the inferior orbital rim to smooth the lid-cheek junction. We report 2 cases of unilateral orbicularis paresis after lower blepharoplasty with supraperiosteal fat transposition. Videos recorded 2 weeks postoperatively showed that the median amplitude of 3 consecutive blinks was markedly reduced in the affected eye of each patient (patient 1: OD = 3.14 mm, OS = 8.43 mm; patient 2: OD = 4.33 mm, OS = 8.50 mm). At 6 months postoperatively, blink amplitude was symmetrical, and symptoms related to ocular exposure had resolved. Motor nerve fibers innervating the pretarsal upper and lower orbicularis oculi muscles follow a sub- and intramuscular course in the medial portion of the lower eyelid. Surgical procedures in this region may therefore injure these nerves, resulting in orbicularis paresis. A subperiosteal approach to orbital fat transposition may help avoid this complication.