Pathophysiology
Lagophthalmos can arise from a malfunction of the Facial nerve. Lagopthalmos can also occur in comatose patients having a decrease in orbicularis tone, in patients having palsy of the facial nerve (7th cranial nerve), and in people with severe skin disorders such as ichthyosis.
Today, lagophthalmos may arise after an overenthusiastic upper blepharoplasty. Blepharoplasty is an operation performed to remove excessive skin overlying the upper eyelid (suprapalpebral hooding) that often occurs with aging. This can appreciably improve the patient's appearance, and make the patient look younger. If, however, excessive skin is removed, the appearance is unnatural and "lagophthalmos" is one of the signs of such excessive skin removal.
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