What is lagophthalmos?
Lagophthalmos mentions the inability to fully close the eyelids. The space between the upper and lower lids exposes the ocular surface, causing dryness problems that can be aggravated and threaten the integrity of the eye and the quality of vision.
Symptoms of lagophthalmos
The main symptom of lagophthalmos is not being able to close your eyes. If you have nocturnal lagophthalmos, you may not even know it. The expression for these additional symptoms in one or both eyes if you reason you have lagophthalmos:
- Increased tears
- Foreign body sensation, which is the sensation of something rubbing against the eye
- Pain or irritation, especially in the morning.
Nocturnal lagophthalmos is the incapability to close the eyelids during sleep. It can reduce the quality of sleep because symptoms related to the exposure or, if severe, cause damage to the cornea (exposure keratopathy). The degree of lagophthalmos can be minor (dark lagophthalmos) or quite obvious.
It is often caused by an abnormality of the eyelid that prevents complete closure. Treatment may include surgery to correct poor eyelid position. Point plugs can be used to increase the amount of lubrication on the surface of the eyeball by blocking some of the tear drainage ducts. Eye drops can also be used to provide additional lubrication or to stimulate the eyes to increase tear production.
The condition is not widely understood; in one case, a passenger was removed from a US Airways flight because of it.
Causes of lagophthalmos
Lagophthalmos is caused by the following three main causes:
- Orbicularis muscle function failure of the eyelids. This is the most common cause. It may be paralytic, due to the fact that the facial intracranial nerve affects the orbicularis oculi muscle, or spastic, as seen in thyrotoxicosis.
- The excessive bulge of the globe in the orbit. Lagophthalmos can accompany proptosis or buphthalmos (enlarged cornea due to elevated intraocular pressure in young children), even though the eyelids are normal, not covering the eye with proptosis.
- The inadequate vertical dimension of the upper or lower eyelid. It can be structural when the retraction or shortening of the eyelids is due to scarring or atrophy after injury (eg burns) or illness. Babies with a collodion membrane may have temporary lagophthalmos due to the restrictive effect of the membrane on the eyelids.
- During sleep, some degree of physiological lagophthalmos can normally occur. Functional lagophthalmos in an unconscious patient can be very troublesome.
Treatments of lagophthalmos
In treating lagophthalmos, the main goal is to prevent exposure to keratitis (inflammation of the cornea), as well as to try to restore eyelid function.
The first treatment plan is usually to keep the eyes hydrated. Blinking usually prevents dryness by dispersion the tear film and meibomian gland secretion over the surface of the conjunctiva and cornea. As patients with lagophthalmos cannot blink normally, an ophthalmic ointment or lubricating eye drops are usually applied both day and night. In extreme cases, taping the lid closed and using a humid chamber to prevent the surface of the eyeball from drying out could remedy extreme dryness. If the condition is acute, botulinum toxin injections into the levator eyelid may allow for better occlusion of the eye.
Permanent treatments will often target the paralyzed facial nerve. For example, facial nerve repair or facial nerve crossover graft can restore the function of the eyelid muscles and also help restore facial symmetry. These procedures are generally not used in older patients.
If conventional surgical procedures do not improve the condition, a second option is a procedure known as tarsorrhaphy. This includes sewing the lids together partially, to narrow the lid opening. Other similar techniques, such as eyelid loading, involve placing a small weight on the upper eyelid, thus increasing the downward pull on it, so that this will gradually cause the eye to close when forced to close. The weight is light enough to experience a gravitational pull and is often made of gold.
In summary, It is most often caused by facial nerve palsy and often has a good recovery rate if treated right away. Understanding the cause is essential in determining which treatment strategy will offer the best success rate. Treatment of the underlying condition should improve facial nerve function and cosmetic appearance, although unfortunately, there are some conditions where this can be difficult.
Diagnosis of lagophthalmos
The diagnosis of lagophthalmos is mainly clinical.
- A slit-lamp examination by an ophthalmologist may show interpalpebral punctate epithelial keratopathy, which is a diagnosis of this disease or incomplete blinking. The distribution of punctate epithelial keratopathy depends on the position of the cornea during sleep in patients with nocturnal lagophthalmos.
- The external examination for complete eyelid closure should be performed with the patient gently closing the eyes.
- Acute dysfunction of the seventh intracranial nerve, due to Bell’s palsy, trauma, or iatrogenic injury, can cause this disease. In cases of understated weakness of the orbicularis oculi muscle, manual distraction of the eyelids throughout forced closure can expose a weakness that can cause nocturnal lagophthalmos or incomplete blinking.
- It is important to check corneal sensitivity to rule out any component of fifth intracranial nerve dysfunction.
- The vertical dimension of the upper and lower eyelid skin should be evaluated in patients with alleged lagophthalmos. In the lower lids, vertical thinning is usually apparent and manifests as a “sclera show” and eyelid retraction. However, in the upper eyelids, the lid margin often rests at a normal height, and only with the downward distraction of the eyelid does vertical shortening of the skin become apparent.
- In all patients suspected of this disease, the function of the superior levator palpebral muscle should be measured (during the eyelid excursion from top to bottom). Patients with inadequate mobility of the upper eyelid retractors may have this disease notwithstanding a normal amount of vertical skin.
- The symblepharon between the bulbar and palpebral conjunctiva in the superior cul-de-sac can also limit the downward excursion of the upper eyelid, thus causing this disease.
- The balloon bulge increases the amount of eyelid excursion required to completely cover the cornea during eye closure. It associated with proptosis can cause exposure to keratopathy.
- Nocturnal lagophthalmos causes a foreign body sensation and watery eyes upon waking.
- Comatose patients usually present with this disease due to the inadequate tone of the seventh central intracranial nerve.
Complications of lagophthalmos
- Untreated lagophthalmos leaves your eyes vulnerable to scratches and other injuries because they are not protected by your eyelids.
- Continuous eye exposure can also lead to exposure keratopathy, which has the same symptoms as lagophthalmos. Exposure keratopathy can eventually cause the cornea, the clear front part of the eye, to swell or become thin. It can also lead to a corneal ulcer.
- Surgery to treat this disease can also have complications. Tarsorrhaphy can leave permanent scars, while gold-weight implants can begin to move away from their original location. Be sure to follow your doctor’s post-surgery instructions to avoid additional problems.
How can it be prevented?
In general, It cannot be prevented, unless it is the result of retraction of the eyelid after blepharoplasty surgery through the skin or other surgical scars. In principle, it is important to detect it, to establish if it represents any risk to vision or the eye and to take the necessary measures for its treatment.
Is lagophthalmos common?
Nocturnal lagophthalmos (partial opening of the eyes during sleep) is an anatomical irregular in the usual human population; in fact, it occurs in 23% of the population.
Can lagophthalmos be cured?
Work with your physician to figure out the underlying cause. Contingent on the cause, you can treat this disease with also surgery or products to help keep your eyes moisturized and protected.