The inability to fully close your eyelids while sleeping is a condition known as nocturnal lagophthalmos. This means the delicate surface of the eye, which should be protected and lubricated overnight, is instead exposed to the air. Affecting up to 20% of the population, this issue is often overlooked or undiagnosed because a person is unaware of it during sleep. This exposure is a significant cause of persistent morning eye discomfort.
The Causes of Nocturnal Lagophthalmos
The causes for incomplete eyelid closure during sleep are varied, often involving issues with the muscle, the controlling nerve, or the physical structure of the eye itself. A common cause is damage to the facial nerve (the seventh cranial nerve), which controls the orbicularis oculi muscle responsible for closing the eyelid. Conditions like Bell’s Palsy, stroke, or trauma can lead to nerve weakness or paralysis, preventing the muscle from contracting fully.
Anatomical issues can also predispose someone to the condition. Prominent eyeballs (exophthalmos), often associated with Graves’ disease, can make it physically difficult for the eyelids to cover the entire eye surface. Eyelid surgeries, such as blepharoplasty, or conditions like floppy eyelid syndrome, can alter the eyelid structure enough to impair complete closure. Some people are simply born with eyelids that do not fully meet, a congenital factor that may be the sole cause of nocturnal lagophthalmos.
Health Risks from Eye Exposure
The consequences of eye surface exposure range from daily discomfort to serious complications. When the eyelids do not seal, the tear film evaporates much faster, leading to chronic dry eye symptoms most pronounced upon waking. This constant drying causes irritation, redness, and a gritty sensation.
Over time, the chronic lack of moisture and protection can cause direct damage to the cornea, the clear outer layer of the eye. This condition is called exposure keratopathy, where the corneal surface sustains micro-scratches and abrasions. In severe, untreated cases, these abrasions can progress to painful corneal ulcers, which carry a risk of infection and potential scarring that may permanently impair vision.
Non-Prescription Eye Protection Methods
For individuals with mild to moderate nocturnal lagophthalmos, several non-prescription methods can be implemented immediately to protect the eye surface. The simplest approach involves using over-the-counter lubricating eye drops (artificial tears) throughout the day and before bedtime. For enhanced overnight protection, a thicker, preservative-free lubricating ointment can be applied directly into the eye just before sleep; the ointment’s viscosity creates a physical barrier and helps slow tear evaporation.
A physical barrier is also effective using external devices. Moisture chamber goggles or specialized sleep masks fit snugly around the eyes, trapping natural moisture and creating a localized, high-humidity microenvironment. Wearing a humidifier in the bedroom can also raise the ambient moisture level of the air, which helps reduce the rate of tear film evaporation. For a more direct solution, medical-grade, hypoallergenic paper tape can be used to gently secure the upper and lower eyelids closed. This technique requires careful practice to ensure the tape is applied without pulling the skin and is completely removed without irritation in the morning.
When to Seek Medical Treatment
While self-care methods can manage symptoms, professional medical consultation is necessary if symptoms persist, worsen, or if there are signs of infection, such as severe pain or sudden blurred vision. An eye care specialist, typically an ophthalmologist or optometrist, can confirm the diagnosis through a physical examination, including a slit lamp assessment of the cornea. They will also investigate potential underlying causes, such as a recent neurological event or an undiagnosed thyroid condition.
If conservative treatments are insufficient, a doctor may recommend advanced interventions. Prescription medications, including stronger gels or anti-inflammatory drops, may be used to treat existing corneal damage or inflammation. For cases related to facial nerve paralysis, small gold or platinum weights can be surgically implanted into the upper eyelid to assist with closure using gravity. A temporary tarsorrhaphy, where the eyelids are partially sewn together to narrow the opening, is sometimes performed to protect the eye surface while a patient recovers from a temporary condition.