Symptomatic nocturnal lagophthalmos.

Nocturnal lagophthalmos producing symptoms of corneal exposure is not uncommon. We diagnosed 40 patients with the condition over a six-month period. In 12 (30%), alcohol intoxication preceded the symptoms. Other factors included the use of hynotics, cosmetic blepharoplasty, botulinum toxin injection for blepharospasm, facial palsy, dysthyroid eye disease and cicatrising skin disease of the lids. In the largest group (17 patients, 42%), no cause could be found, but five of these had either first-degree relatives who slept with their eyes open, or had been observed with nocturnal lagophthalmos. In most patients, symptoms were unilateral. Testing of Bell's phenomenon did not predict eye position during sleep as manifested by distribution of punctate corneal staining. All patients were relieved of their symptoms by simple treatment modalities and none required surgery.