Lagophthalmos or incomplete closure of the eyelids is often overlooked during routine clinical examination.  It can be complete in cases of Bells or facial nerve palsy when the patient is asked to voluntarily close the eyelids or quite subtle, being present only during involuntary blinking.  Failure to detect lagophthalmos can result in exposure keratopathy and epithelial defect following otherwise routine eye surgery.  Management involves frequent regular use of non-preserved lubricants and prevention of on-going exposure.