Lagophthalmos is the inability to close the

eyelid An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. The human eyel ...

s completely. Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Butterworth-Heinemann, Boston 1997.

Blinking Blinking is a bodily function; it is a semi-autonomic rapid closing of the eyelid. A single blink is determined by the forceful closing of the eyelid or inactivation of the levator palpebrae superioris and the activation of the palpebral portio ...

covers the eye with a thin layer of tear fluid, thereby promoting a moist environment necessary for the cells of the exterior part of the eye. The tears also flush out foreign bodies and wash them away. This is crucial to maintain lubrication and proper eye health. If this process is impaired, as in lagophthalmos, the eye can suffer abrasions and infections. Lagopthalmos leads to corneal drying and

ulceration An ulcer is a discontinuity or break in a bodily membrane that impedes normal function of the affected organ. According to Robbins's pathology, "ulcer is the breach of the continuity of skin, epithelium or mucous membrane caused by sloughing o ...

Type(s)

Nocturnal lagophthalmos is the inability to close the eyelids during sleep. It may reduce the quality of sleep, cause exposure-related symptoms or, if severe, cause corneal damage (

exposure keratopathy Exposure keratopathy (also known as exposure keratitis) is medical condition affecting the cornea of eyes. It can lead to corneal ulceration and permanent loss of vision due to corneal opacity. Normally, corneal surface is kept moist by blinking ...

). The degree of lagophthalmos can be minor (obscure lagophthalmos) or quite obvious. It is often caused by an anomaly of the eyelid that prevents full closure. Treatment may involve surgery to correct the malposition of the eyelid(s). Punctal plugs may be used to increase the amount of lubrication on the surface of the eyeball by blocking some of the tear-drainage ducts. Eye drops may also be used to provide additional lubrication or to stimulate the eyes to increase tear production. Public awareness of the condition is not widespread; in one instance, a passenger was removed from a

US Airways US Airways (formerly USAir) was a major United States airline that operated from 1937 until its merger with American Airlines in 2015. It was originally founded in History of aviation in Pittsburgh, Pittsburgh as a mail delivery airline called ...

flight because of it.

Pathophysiology

Lagophthalmos can arise from a malfunction of the

facial nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of tas ...

.Kliniska Färdigheter: Informationsutbytet Mellan Patient Och Läkare, LINDGREN, STEFAN, Lagopthalmos can also occur in comatose patients having a decrease in orbicularis tone, in patients having palsy of the facial nerve (seventh cranial nerve), in people with severe exophthalmos and in people with severe skin disorders such as

ichthyosis Ichthyosis is a family of genetic skin disorders characterized by dry, thickened, scaly skin. The more than 20 types of ichthyosis range in severity of symptoms, outward appearance, underlying genetic cause and mode of inheritance (e.g., dominan ...

. Today, lagophthalmos may arise after an upper

blepharoplasty Blepharoplasty (Greek: ''blepharon'', "eyelid" + ''plassein'' "to form") is the plastic surgery operation for correcting defects, deformities, and disfigurations of the eyelids; and for aesthetically modifying the eye region of the face. With t ...

, which is an operation performed to remove excessive skin overlying the upper eyelid (suprapalpebral hooding) that often occurs with aging. This can make the patient look younger, but if too much skin is removed, the appearance is unnatural and lagophthalmos may occur.

Treatment

Treatment of lagophthalmos can include both supportive care methods as well as surgical options. If unable to receive surgery, patients should be administered artificial tears at least four times per day to the cornea to preserve the tear film. In preparation for surgery, a patient may undergo a

tarsorrhaphy Tarsorrhaphy is a surgical procedure in which the eyelids are partially sewn together to narrow the eyelid opening. It may be done to protect the cornea in cases of corneal exposure, as a treatment for Graves' ophthalmopathy, Möbius syndrome or ...

, in which the eye is partially sewn shut temporarily to further protect the cornea as the patient waits for care. Multiple surgical treatments exist for lagopthalmos, but the most prevalent method includes weighing the upper eyelid down by surgically inserting a gold plate. Because of possible complications in conjunction with both the upper and lower eyelid, a second surgery may be required to tighten and elevate the lower eyelid to ensure that both the upper and lower eyelids can fully close and protect the cornea.

Etymology

The name of the condition derives from the Greek (, '

hare Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The ge ...

'), referring to the myth that hares sleep with their eyes open.

References

External links

{{Eye pathology Disorders of eyelid, lacrimal system and orbit