Lagophthalmos is the inability to fully close the eyelids, and it can range from a barely noticeable gap during sleep to a wide-open eye that dries out and develops corneal damage. The most common cause is facial nerve paralysis, but it also shows up after eyelid surgery, burns, trauma, and in a surprisingly large slice of the population during sleep alone. Because the cornea depends on a thin, constantly refreshed layer of tears to stay healthy, even a small gap in lid closure can set off a chain of problems that affect vision and comfort.
What Causes Lagophthalmos
Closing your eyelids is not as simple as it sounds. The orbicularis oculi, the circular muscle surrounding each eye, has to contract in a coordinated pattern across several segments to bring the upper and lower lids together. Recent research using intramuscular electromyography has shown that different segments of this muscle activate in distinct patterns depending on the type of blink or closure, and that precise neural control across those segments is what produces natural eyelid movement.1PubMed Central. Human eyelid behavior is driven by segmental neural control of the orbicularis oculi When any part of that chain breaks down, the lid stops meeting its target.
The single biggest driver is facial nerve paralysis, often called paralytic lagophthalmos. The facial nerve (cranial nerve VII) supplies the orbicularis oculi, so when that nerve is damaged or inflamed, the muscle goes slack on the affected side. Bell’s palsy, an idiopathic inflammation of the facial nerve, accounts for the majority of cases in surgical series, representing up to about 72 percent of some cohorts.2PubMed Central. Upper Eyelid Static Surgical Approaches for the Treatment of Facial Palsy-Induced Lagophthalmos: A Systematic Review Other causes of facial nerve damage include acoustic neuroma surgery, parotid gland surgery, head trauma, and stroke.
Beyond nerve problems, lagophthalmos can be cicatricial, meaning scar tissue physically prevents the lid from closing. Facial burns involving the area around the eye are a classic example: the skin contracts as it heals, pulling the lid away from the globe.3PubMed Central. Scleral Contact Lens to Preserve a Corneal Graft in Chronic Lagophthalmos Trauma, chemical injuries, and certain surgeries that remove too much tissue can produce the same effect. A third major category is nocturnal lagophthalmos, which happens only during sleep and has its own set of quirks worth discussing separately.
Nocturnal Lagophthalmos
Roughly 5 percent of the population sleeps with their eyes at least partially open, a condition known as nocturnal lagophthalmos.4PubMed. Lagophthalmos Many people who have it do not realize it until a partner mentions it or they start waking up with dry, gritty, or red eyes. In one documented case, a woman’s eyes stayed closed during lighter stages of sleep but opened partially during deep sleep and wide open during the rapid eye movement (REM) stage, with visible eye movements throughout. She reported morning redness, light sensitivity, and tearing and was prescribed lubricating drops for nighttime use.
A large survey of 2,000 people found that about 4.5 percent reported nocturnal lagophthalmos, and these individuals were younger on average and more likely to have dry eye disease. People in the nocturnal lagophthalmos group reported significantly more eye symptoms upon waking, including difficulty opening their eyes, a foreign body sensation, and eye pain in the morning. Night-shift workers were also overrepresented in this group.5PubMed Central. Nocturnal Lagophthalmos and Sleep Quality in Patients with Dry Eye Disease If you consistently wake up feeling like you have sand in your eyes, nocturnal lagophthalmos is a possibility worth raising with an eye doctor, especially if someone has told you your eyes stay open at night.
Why an Open Eye Gets Damaged
The cornea is one of the few tissues in the body that has no blood vessels. It gets its oxygen and nutrients partly from the air and partly from the tear film. Every time you blink, the lids spread a fresh layer of tears across the surface, keeping it moist and sweeping away debris. When the lids cannot close fully, the exposed portion of the cornea dries out. Over hours, the surface epithelial cells begin to break down, a condition called exposure keratopathy.
This is not a trivial nuisance. In a case report of a 21-year-old woman with bilateral idiopathic lagophthalmos, the chronic corneal exposure had already caused corneal scarring in both eyes and measurable vision loss by the time she sought care.6PubMed Central. Exposure Keratopathy: An Idiopathic Lagophthalmos Case Report The lower portion of the cornea tends to suffer most because the upper lid does the bulk of the work during closure, and gravity pulls tears downward, leaving the bottom zone exposed first.
In intensive care units, the stakes are even higher because sedated patients cannot blink at all, and staff may not notice incomplete closure. One ICU study found a statistically significant link between clinically detected lagophthalmos and exposure keratopathy. Patients who also had poor Bell’s phenomenon, the normal reflex where the eyeball rolls upward and outward during attempted lid closure, were at additional risk.7PubMed Central. Developing an AI-Based Model for Lagophthalmos and Bell’s Phenomenon Detection in Intensive Care Unit Patients: A Gold Standard Comparison Bell’s phenomenon is a kind of built-in safety backup: even if your lids do not fully shut, the cornea rolls out of the exposed gap. When both defenses fail, corneal damage can progress quickly.
How Doctors Evaluate It
Diagnosis starts with a straightforward observation. The clinician asks you to close your eyes gently and measures the gap, if any, between the upper and lower lids. This is typically done in the office under normal lighting, and the examiner looks not just at how much the lids close but at how the globe rotates underneath. Bell’s phenomenon is specifically checked by watching whether the eye rolls upward and outward on attempted closure.8PubMed. Nocturnal lagophthalmos after levator surgery: clinical correlates and risk factors
For nocturnal lagophthalmos, daytime exams can miss the problem entirely because you are awake and actively closing your lids. Some clinicians now ask patients or family members to take photographs during sleep, and in research settings, video polysomnography, the same overnight recording used for sleep apnea, has captured exactly how and when the lids open during different sleep stages. In the ICU setting, researchers are developing AI-based models that use camera images to detect lagophthalmos and absent Bell’s phenomenon in sedated patients, aiming to catch the problem before corneal damage develops.9PubMed Central. Developing an AI-Based Model for Lagophthalmos and Bell’s Phenomenon Detection in Intensive Care Unit Patients: A Gold Standard Comparison
Non-Surgical Treatments
For mild cases, especially nocturnal lagophthalmos without nerve damage, the first-line approach is protecting the corneal surface rather than fixing the lid itself. Lubricating eye drops during the day and thicker ointments at bedtime are the standard starting point. Some clinicians recommend taping the eyelids shut at night with medical tape, or using moisture-chamber goggles that trap humidity around the eyes while you sleep. Punctal plugs, tiny inserts placed in the tear drainage channels to keep tears on the surface longer, can also help when dryness is hard to control with drops alone.10PubMed. Lagophthalmos
When those measures are not enough, scleral contact lenses are an increasingly important option. Unlike a standard soft contact lens, a scleral lens is a large-diameter, custom-fit, gas-permeable lens that vaults over the entire cornea without touching it, resting instead on the white of the eye. The space underneath fills with a reservoir of artificial tears, keeping the cornea bathed in fluid even when the lid does not close properly.11PubMed Central. Adjunct Use of Therapeutic Scleral Lens for Exposure Keratopathy after Severe Chemical Burn In one case series, custom-designed scleral devices called PROSE (Prosthetic Replacement of the Ocular Surface Ecosystem) proved effective for patients with exposure keratopathy who had already failed conventional therapies, serving as a viable alternative to lid surgery.12Eye & Contact Lens. Prosthetic Replacement of the Ocular Surface Ecosystem Scleral Lens Therapy for Exposure Keratopathy PROSE treatment is limited to a small number of specialty centers, but commercially available scleral lenses are now widely fitted by trained optometrists and can achieve similar protection.
Surgical Options
When lagophthalmos is persistent and non-surgical measures cannot keep the cornea healthy, surgery becomes necessary. There is no single procedure that fits every patient. The choice depends on what is causing the incomplete closure, how much gap exists, and whether the paralysis is expected to recover.
Gold Weight Implants
For paralytic lagophthalmos, one of the most common procedures is implanting a small gold or platinum weight into the upper eyelid. The added mass uses gravity to help the lid drop closed when the orbicularis muscle cannot do the job. A ten-year review of 78 patients who received gold weight implants found an overall satisfaction rate of about 89 percent. The highest satisfaction related to improved visual acuity and the lowest to the ongoing need for artificial tears, suggesting the weights help but do not entirely eliminate dryness. About 27 percent of patients experienced complications, the most common being extrusion, where the weight works its way through the skin.13PubMed Central. The role of gold weight implants in the management of paralytic lagophthalmos Despite this, the procedure remains a workhorse for facial palsy patients because it can be done under local anesthesia, is reversible if nerve function returns, and produces a relatively natural blink.
Tarsorrhaphy and Canthoplasty
Tarsorrhaphy involves partially stitching the outer corners of the upper and lower eyelids together, narrowing the opening the lid has to cover. Even a small lateral tarsorrhaphy of 3 millimeters or less can make a meaningful difference in corneal protection for patients with moderate-to-severe keratopathy.14PubMed. Levator recession and minimal lateral tarsorrhaphy for the management of lagophthalmos and corneal exposure in facial palsy The cosmetic trade-off is a slightly smaller eye opening, which bothers some patients but is far preferable to losing corneal transparency.
A related technique, medial canthoplasty, tightens the inner corner of the eyelids to narrow the palpebral fissure from the nasal side. A review of 48 patients who underwent medial canthoplasty found that 85 percent showed a post-operative reduction in lagophthalmos and 90 percent had improvement in corneal surface findings.15PubMed Central. Medial canthoplasty for the management of exposure keratopathy This approach is particularly useful for patients with lax lower lids or medial ectropion contributing to exposure.
Levator Recession
In some cases of paralytic lagophthalmos, the upper lid sits too high because the levator muscle, which normally lifts the lid, is unopposed by the weakened orbicularis. Levator recession surgically weakens or lengthens the levator to let the lid sit lower at rest. One study combined levator recession with selective small lateral tarsorrhaphy and found that both groups, those who received the additional tarsorrhaphy and those who did not, achieved similar reductions in lid gap and in the distance from the upper lid margin to the center of the pupil.16PubMed. Levator recession and minimal lateral tarsorrhaphy for the management of lagophthalmos and corneal exposure in facial palsy
Lagophthalmos After Blepharoplasty
Cosmetic and functional eyelid surgery, or blepharoplasty, is one of the more common elective procedures in facial plastic surgery, and lagophthalmos is a recognized complication. The mechanism is mechanical: if too much skin is removed from the upper lid, there simply is not enough tissue left to cover the eye. The general guideline is that at least 20 millimeters of skin should remain between the brow and the lid margin at the center of the eyelid after excision for the lid to close properly.17Clinics in Plastic Surgery. Recognizing and Managing Complications in Blepharoplasty Other contributing factors include orbicularis muscle injury during surgery, excessive muscle removal, and lid retraction from scarring.
Post-blepharoplasty lagophthalmos is usually most noticeable in the first weeks after surgery, when swelling and stiffness hold the lid up. Mild cases often resolve as healing progresses and the tissue softens, but if too much skin was taken, the problem becomes permanent. This is one reason experienced surgeons tend to err on the side of conservative excision, preferring a second touch-up procedure over an irreversible overcorrection.
Lagophthalmos in Moebius Syndrome
Moebius syndrome is a rare congenital condition involving underdevelopment of cranial nerves VI and VII, which control lateral eye movement and facial expression. Because the facial nerve does not function normally from birth, people with Moebius syndrome live with lagophthalmos their entire lives rather than acquiring it from an event like Bell’s palsy. A study that conducted focus groups with 15 participants, including adolescents, found that all had lagophthalmos with visible scleral show, ptosis, and lid retraction. The median eyelid closure score indicated incomplete closure with roughly one-third of the white of the eye still visible.18PubMed. Through their eyes: Navigating life with limited eyelid closure in patients with Moebius syndrome
Living with permanent lagophthalmos from birth creates a different set of challenges than the acquired form. These individuals have never known what it feels like to close their eyes fully. Their corneas have adapted somewhat, often developing increased tolerance to exposure, but they still face chronic dryness and the psychosocial burden of eyes that appear “always open.” The qualitative research with this group emphasized how much daily life revolved around managing their eyes, from choosing seating positions to avoid drafts to routinely applying drops throughout the day. For children, the visible difference in their eyes and facial expression can be a source of teasing and social difficulty that goes well beyond the medical aspects.
Flat-Faced Dog Breeds and the Same Problem
Lagophthalmos is not a uniquely human condition. Brachycephalic dog breeds, those with flat faces and prominent eyes like pugs, bulldogs, and shih tzus, have an extremely high prevalence of ocular surface disorders directly linked to their skull shape. Their shallow eye sockets cause the eyes to protrude, and the lids often cannot close fully over the exposed cornea. This combination, sometimes termed brachycephalic ocular syndrome, leads to chronic corneal drying, pigmentation, ulceration, and in severe cases, loss of the eye entirely.19Veterinary Ophthalmology. The pandemic of ocular surface disease in brachycephalic dogs: The brachycephalic ocular syndrome Many of these dogs require daily lubricating eye drops for their entire lives, and some need surgical correction of their lid openings. The parallel to human cicatricial or mechanical lagophthalmos is striking and has made these breeds useful, if unfortunate, models for understanding chronic corneal exposure.
When to Seek Help
The tricky thing about lagophthalmos is that mild cases fly under the radar. You may attribute morning eye redness to allergies, or assume that gritty eyes are just dry eye from screen time. A few signs point more specifically toward incomplete lid closure: symptoms that are worse upon waking and improve as the day goes on, redness concentrated on the lower half of the cornea, and a partner reporting that your eyes stay partly open during sleep. If you have had any kind of facial nerve issue, eyelid surgery, facial trauma, or burn, incomplete lid closure should be actively checked for rather than waited on. In ICU or post-surgical settings, nursing staff should be aware that lagophthalmos can develop quickly in sedated patients and that early detection prevents corneal damage that may otherwise become irreversible.