Lagophthalmos Paralytic lagophthalmos SNOMEDCT_US:59890007 Patients with facial nerve palsy have a characteristic facial asymmetry and drooping of the angle of mouth. The temporal and zygomatic branches of facial nerve supply the forehead and eyelid muscles. Their involvement in a disease leads to paralysis of orbicularis oculi muscle resulting in lagophthalmos and ectropion. A type of lagophthalmos that occurs in association with facial nerve palsy. UMLS:C0155197