Lagophthalmos

What is Lagophthalmos?

Lagophthalmos is a condition where the eyelids can’t properly close. It’s necessary for our eyelids to completely shut and blink normally to keep the eye’s surface healthy and a thin layer of tears stable. If someone can’t blink or fully close their eyes, their cornea – the front part of the eye – might be exposed, which can dry out the tear layer and potentially lead to a condition called exposure keratopathy. If this condition worsens, it can form corneal ulcers and even result in the cornea bursting. So it’s really important to spot lagophthalmos early on and start finding out why it’s happening and how to manage it. Most of the time, lagophthalmos is caused by the facial nerve not working correctly, causing a form of lagophthalmos called paralytic lagophthalmos.

There are plenty of reasons why the facial nerve might not work as it should. Therefore, a thorough look into the patient’s medical history and detailed tests are necessary to treat the root cause. The main goals in treating lagophthalmos are to stop further damage to the cornea and get the eyelid working better. Because the face may look different with lagophthalmos, this could also affect a person’s mental health, so it’s essential they feel okay about their appearance again.

There are two types of treatment methods – medical and surgical. Medical treatment is all about enhancing the layer of tears on the eye’s surface. Surgical treatments can either be dynamic (changing with the patient) or static (unchanging) and mainly focus on fixing the eyelid’s function or covering up the eye appropriately. The best type of treatment and surgical technique will depend on what’s causing lagophthalmos, how severe it is, and where it’s located. The patient’s age, general health, and personal needs also play a part in this decision.

What Causes Lagophthalmos?

Paralytic Lagophthalmos is a condition caused by facial nerve paralysis which results in the inability to close the eye fully. This might happen due to many reasons.

Infections which include ear infections, viruses like herpes or flu, bacterial infections like tuberculosis, Lyme disease, or fungal infections can cause this condition. This is more prevalent in people with weakened immune systems (like those with AIDS).

Facial nerve paralysis can also be caused by any form of trauma to the face, including injuries sustained during birth or fractures to the skull.

Certain conditions or tumors, such as Schwannoma (a tumor in nerve tissues), teratoma (a tumor made up of several different types of tissue), neurofibromatosis type 2 (a disorder characterized by the growth of noncancerous tumors in the nervous system), or leukemia can also contribute to this condition.

Things like diabetes, hypertension, vitamin A deficiency, and hyperthyroidism or metabolic conditions can also cause facial nerve paralysis.

Exposure to certain toxins, such as alcohol, arsenic, tetanus, or carbon monoxide can also bring about facial nerve paralysis.

Certain surgical procedures involving the face, as well as adverse reactions to immunizations or dental procedures, can also cause this condition.

Neurological conditions like Millard-Gubler syndrome, a condition that affects the nerves in the brain, or Foix-Chavany-Marie syndrome, a rare neurological disorder, can also cause this condition.

Paralytic Lagophthalmos can also be a birth defect due to conditions like Mobius syndrome, Goldenhaar syndrome, or Ichthyosis.

Sometimes, the cause of the condition can be unknown, as in several diseases like Bell’s palsy, Guillain-Barre syndrome, or Multiple sclerosis.

Scarring Lagophthalmos happens when the eyelids have scars, affecting their ability to close properly. These scars could be because of sun damage, chemical burns, certain skin conditions, or trauma.

Nocturnal Lagophthalmos, on the other hand, occurs when the eyes do not fully close during sleep. This can cause symptoms of dry eyes and can be challenging to diagnose. This can also lead to sleep problems.

Finally, an incomplete blink, which can potentially cause Lagophthalmos, can be seen in patients with Parkinson’s disease or eye muscle disorders like myotonic dystrophy and chronic progressive external ophthalmoplegia.

Risk Factors and Frequency for Lagophthalmos

Every year in the United States, between 30 and 40 people in every 100,000 experience facial nerve paralysis. The most common reason for this condition is Bell’s palsy, which accounts for up to 80% of all cases. Bell’s palsy is characterized by a sudden, one-sided facial paralysis that typically gets better on its own. The exact cause is unknown, but there may be a link to viral infections. Symptoms can vary and may include ear pain, heightened sensitivity to sound, deafness, changes in taste, numbness in the cheek and mouth, and eye pain. Fortunately, the outlook for people with Bell’s palsy is usually very good, with up to 84% of patients regaining full facial nerve function.

• Between 30-40 out of every 100,000 people experience facial nerve paralysis each year in the United States.
• Up to 80% of these cases are the result of Bell’s palsy.
• Bell’s palsy is a sudden facial paralysis on one side and usually recovers on its own.
• While we don’t know the exact cause, it may be associated with viral infections.
• Common symptoms include ear pain, heightened sensitivity to sound, deafness, changes in taste, numbness in the cheek and mouth, and eye pain.
• Most people (up to 84%) recover full function of their facial nerve.

Signs and Symptoms of Lagophthalmos

The doctor will make a thorough assessment of your health history to determine the cause of lagophthalmos, which is the inability to fully close your eyes. If you’ve had recent surgery or any trauma related to your eyes, facial area, or head, this could have caused the condition. Past infections, specifically herpes zoster, might also be a potential cause. Other health conditions like thyroid disease or sleep apnea can also result in lagophthalmos. It’s important to note that lagophthalmos can sometimes result from acute facial nerve paralysis, which usually leads to a sudden one-sided loss of facial motor function, causing distinct facial asymmetry.

When the issue is caused by damage to the lower motor neurons – the nerve cells connecting the brain to the muscles – the entire half of the face will be affected. In contrast, if the damage is restricted to the upper motor neurons – nerves within the brain and spinal cord – the forehead will not be affected. If complete facial paralysis is the result of damage to the lower motor neurons, the patient will experience the following symptoms:

• Loss of forehead creases
• Flattening of the creases around the nose and mouth
• Drooping of the eyebrow
• Lower eyelid turning outwards
• Upper eyelid retraction
• Inability to fully close the eyes (lagophthalmos)
• Drooping of the mouth
• Problems with speech
• Possible emotional distress due to physical changes to the face

Testing for Lagophthalmos

During a clinical examination, a doctor will look for specific visible signs such as an incomplete blink, protruding eyes, unusual eyelid positions, and the quality of your eye’s natural protective reflex (called Bell’s phenomenon). They will also check if a gap is present between your upper and lower eyelids when you close your eyes, a condition known as lagophthalmos. If this is the case, they will measure the distance of this gap, and document how much of the eyeball or cornea is exposed.

As part of the examination, your doctor will also run tests to make sure all the nerves in your face are working properly, with a particular focus on those responsible for eye movements and muscle function around the eye.

Using a medical device called a slit lamp, your doctor will take a closer look at the white part of your eye for any redness or swelling. They will also check the sensitivity of your cornea, which is the front clear surface of the eye. To identify specific damages to the cornea, a special dye called fluorescein might be used, paying special attention to the lower part of the cornea that ends with the eyelid’s motion. In addition, they will note the duration it takes for your tears to evaporate, which can give insights into the health of your eyes.

Additional tests may be recommended based on what the doctor suspects might be the underlying cause. If thyroid eye disease is suspected due to protruding eyes, thyroid function tests along with CT scans of your orbit (eye socket) may be done. If there are changing and worsening signs of nerve damage, the doctor may order CT/MR scans as a precaution to make sure there’s no bleeding in the brain or a tumor.

Treatment Options for Lagophthalmos

Lagophthalmos, a condition where the eye can’t fully close, is managed through treatments that aim to protect the surface of the eye and address the root cause of the condition.

One common method of managing this condition can be through frequently using artificial tears without preservatives. These can help improve the moisture around the patient’s eye. An ointment can also be used at night, or during the day if the exposure of the cornea, the clear surface at the front of the eye, is severe. Additionally, the eyelids can be taped shut at night to provide further protection for the eye. There are also glasses designed to keep the area around the eye moist which can be beneficial. For immediate relief in more serious cases, a type of gel can be used to expand the area around the eye.

For more serious or lasting cases, a more structured approach is necessary. This commonly involves regular check-ups and examinations to monitor the progression of the condition.

One surgical approach is tarsorrhaphy, a procedure where the eyelids are partly sewn together to protect the cornea. This is usually a temporary method, often used when recovery is expected in the near future. However, over time the stitches can loosen and may not provide sufficient protection to the eye. There can also be complications, such as scarring and ingrown eyelashes.

If the eyelids cannot fully close, patients can have a gold or platinum weight implanted in their upper eyelid. The weight helps improve the closure of the eye by using gravity. Gold was initially chosen as it’s inactive, but platinum is now preferred for having higher density, being less noticeable, and having less chance of causing an inflammatory reaction.

For patients who can’t fully close their eyes due to an overactive upper eyelid retraction (like from thyroid eye disease), surgery can be carried out to pull back the retractor muscles, the muscles that control the movement of the eyelid. Surgeries that involve grafts or reconstruction might be necessary for patients with a shortened eyelid due to a previous surgery. For patients with scarring, additional procedures may be required.

There are also surgeries to tighten and elevate the lower eyelid which can help improve the contact of the lower eyelid with the eye and reduce symptoms. If there’s still corneal exposure after using medication and upper eyelid surgery, lower eyelid elevation through surgery can be an option.

In more severe cases, certain surgical procedures are needed. For instance, severe lagophthalmos as a result of facial nerve paralysis might require a lift of the midface, which could involve a variety of techniques. Other methods to reconstruct the function of the face might also be used.

What else can Lagophthalmos be?

Bell’s palsy is a condition diagnosed when other serious causes of facial paralysis have been ruled out. It’s always crucial to determine whether the believed cause of the condition affects the lower or upper parts of the motor neurons. Essentially, if a condition affects the lower motor neurons, it can generally cause total facial paralysis. A great way to test for this is to ask the patient to raise their eyebrows – this helps to test the functioning of the frontalis (forehead) and orbicularis oculi (eye) muscles.

Noteworthy conditions that affect the lower motor neurons include Bell’s Palsy itself and Ramsay Hunt syndrome. Meanwhile, conditions that affect the upper motor neurons and could cause facial nerve paralysis include things like a cerebral ischemic event, multiple sclerosis, internal bleeding in the skull (intracranial hemorrhage), or cancer (neoplasia).

It’s worth noting that if a patient shows an unusual presentation, recurring or worsening symptoms, additional neurological findings, lack of spontaneous resolution, or any history of cancer in the head, neck, or skin, these are all risk factors that indicate further investigation may be required.

What to expect with Lagophthalmos

The outcome for lagophthalmos, which is the inability to fully close your eyes, really depends on what caused it in the first place. If it’s a milder case and due to something like Bell’s palsy, a condition that causes temporary weakness or paralysis of the muscles in the face, the outlook is very good. Most people with Bell’s palsy see their symptoms go away on their own.

However, severe cases of lagophthalmos can lead to damage of the cornea, the clear front surface of the eye. This could be scarring, something poking through the cornea, or even loss of vision.

Possible Complications When Diagnosed with Lagophthalmos

The problems following eye surgery can be relatively minor, such as dry eye symptoms, to more severe cases including scratches on the cornea, persistent epithelial defects, ulceration, microbial infections of the cornea, and corneal scarring. The cornea may also get a hole in it, which can lead to loss of vision. Band keratopathy, a disease in which calcium deposits form on the cornea, can occur as a result of chronic exposure keratopathy.

The various complications include:

• Dry eye symptoms
• Scratches on the cornea
• Persistent epithelial defects
• Ulceration
• Microbial infections of the cornea
• Corneal scarring
• Corneal perforation leading to visual loss
• Band keratopathy as a result of chronic exposure keratopathy

Preventing Lagophthalmos

People who have lagophthalmos (a condition where one can’t fully close their eyes) face several challenges. It’s crucial for these patients to understand their condition well so that they can manage it properly and reduce any risk of complications. This mainly involves taking care of dry eyes, learning how to tape their eyelids, and if the condition is caused by facial paralysis, they might also need to adapt to challenges with eating, drinking, speaking, expressing emotions, and dealing with the emotional impact.

It can be really helpful if they have access to easy-to-understand information about their condition, and if they’re directed towards support groups where they can meet others facing similar issues. This not only helps them manage their condition better, but can also considerably improve their overall wellbeing and outcome.