What is Benign Essential Blepharospasm?
Blepharospasm is a condition that leads to frequent, involuntary closing of both eyelids due to the contraction of the muscles around the eyes. This falls under a category of disorders called dystonia, which are notable for causing either sustained or intermittent muscle contractions. Dystonia leads to unusual repetitive movements or postures that often have a specific pattern and may involve twisting or shaking. When a person voluntarily moves, it can make the dystonia worse because the muscles become overactive.
Dystonia can occur in any part of the body and can appear at any age. It can impact the body in various ways:
* Focal dystonia impacts just one specific area of the body.
* Segmental dystonia affects two or more connected body regions.
* Multifocal dystonia impacts two or more areas that aren’t connected.
* Hemidystonia affects one half of the body.
* Generalized dystonia affects the torso plus three other areas.
Dystonia’s progression can be constant or increase over time. The frequency of the symptoms can also vary:
* Persistent dystonia is when the dystonia stays the same throughout the day.
* Action-specific dystonia only occurs when doing a particular activity.
* Diurnal fluctuation means the severity of the dystonia varies at different times of the day.
* Paroxysmal dystonia involves sudden episodes of dystonia, usually set off by a specific trigger.
Blepharospasm is one type of focal dystonia that involves involuntary simultaneous contraction of opposing muscles, causing the eyelids to close involuntarily. The first report of patients with blepharospasm dates back to 1910 where Henri Meige described 10 patients with involuntary eyelid closure along with jaw muscle contraction. He referred to this as “Convulsions de la Face” or “convulsions of the face”. This article will further discuss the causes, frequency, history, assessment, and treatment of blepharospasm.
What Causes Benign Essential Blepharospasm?
The exact cause of blepharospasm or eyelid twitching is not fully known. However, it’s suggested that changes in certain genes play a part in causing this condition. In family history, 20% to 30% of cases show blepharospasm, and some particular genes are thought to increase the likelihood of developing this condition. It’s also believed that disturbance in neurotransmitters (chemicals transmitting signals in the brain), structural damage, and previously existing eye disorders can contribute to causing the disease.
Apart from genetics, many environmental factors can make it more likely for a person to develop blepharospasm. For example, people leading stressful lives, particularly those working in high-pressure office jobs or living in highly urbanized areas, may come across this condition more often. Habitual activities like reading, watching television, or using a computer have been linked to a heightened risk of blepharospasm, probably due to eye strain. Apart from these, mental health issues like obsessive-compulsive disorder, depression, and anxiety are found to increase the risk of developing this condition.
Eye irritation symptoms like burning, dryness, or a gritty feeling have been reported in 40% to 60% of blepharospasm patients before the onset of eyelid twitching. Some eye infections, like keratoconjunctivitis or blepharitis, can increase the risk of having this condition. However, when the eye infection is treated, the twitching often improves.
Exploring the genetics side, it’s observed that multiple people in the same family having the condition suggests a genetic link to the disease. Specific genes like GNAL, CIZ1, TOR1A, DRD5, and REEP4 are implicated in the development of blepharospasm. For instance, any changes in the GNAL gene can contribute to dystonia, a movement disorder that involves involuntary muscle contractions. Similarly, changes in other genes named CIZ1, TOR1A, and DRD5 are related to other forms of dystonia and could also be factors in blepharospasm.
Risk Factors and Frequency for Benign Essential Blepharospasm
Benign essential blepharospasm, a condition where your eyelids close or blink uncontrollably, affects 20 to 133 out of every million people worldwide, but this number can change depending on where you live. For instance, in the United States and Europe, blepharospasm is less common than a similar condition called cervical dystonia, but in Italy and Japan, it’s more commonly diagnosed.
Interestingly, blepharospasm is more common in women than men. It’s believed that being post-menopausal could increase a woman’s risk of developing the condition. The ratio of women to men with blepharospasm is 2.3:1, and women may experience symptoms more frequently and severely.
When it comes to age, the condition typically peaks in people aged 50 to 70.
Signs and Symptoms of Benign Essential Blepharospasm
Blepharospasm (BEB) is a condition that is often missed or diagnosed too late. In Japan, it was reported that 60% of patients consulted at least five different doctors before they got the correct diagnosis. The diagnosis of BEB can sometimes take more than five years since the onset of the symptoms, with a third of the patients getting diagnosed within the first year, another third between one to five years, and the remaining third after five years.
In about 42.6% of cases, a stressful life event seemed to trigger the onset of symptoms. Such events could include things like divorce, work-related problems, family illness, parental death, relocating, head injuries, traffic accidents, or a stroke. A study involving 1,116 participants in Tokyo reported that 9.7% of the subjects experienced symptoms following surgery; cataract surgery being the most common.
The spasms caused by blepharospasm usually occur simultaneously and affect both eyes, typically the orbicularis oculi muscle. The severity of these spasms can vary greatly, from an increased rate of blinking to severe cases where the persistent muscle contraction could lead to functional blindness. The disease usually progresses over time, begins with contractions around the eyes and later spreads to the lower face and neck in a condition known as Meige syndrome.
It is not uncommon for some patients with this condition to also have apraxia of eyelid opening (AEO), which is the inability to open the eyes without any muscle spasm. This happens due to spasm of the particular muscle that helps in opening of the eyelid.
Furthermore, it’s important to be aware that patients with BEB often experience depression and anxiety. These mental health conditions can either occur before the onset of the disease or as a result of dealing with it. Therefore, a psychiatric evaluation is often recommended.
Half of the patients might also have eye-related symptoms besides the spasms, with many of them reporting dryness of eyes and sensitivity to light.
There are certain activities or factors that could help alleviate the symptoms for some patients. These include:
- Resting (reported by 35.6% of patients)
- Concentrating on work (12.9%)
- Singing, talking, eating, sleeping, and exercising (2% of patients each)
Unfortunately, 31.7% of the patients could not find anything that relieved their symptoms.
On the flip side, there are also factors that could exacerbate the spasms. These include:
- Fatigue (55.4% of patients)
- Stressful events (46.5%)
- Watching TV (27.7%)
- Bright lights (18.9%)
- Dry eyes (14.9%)
- Feeling unwell (10.9%)
- Reading a book (8.9%)
Testing for Benign Essential Blepharospasm
The process of diagnosing blepharospasm, an involuntary twitching or closure of the eyelids, primarily involves a clinical examination. This involves taking the patient’s medical history which examines the nature of the eyelid spasm. If you’re experiencing blepharospasm, you’ll likely complain of recurring and simultaneous spasms in the muscles around your eyes. These spasms can either make you blink a lot or cause your eyes to remain shut, distracting you from your regular functions.
A diagnostic method using specific criteria including muscle movements, sensory ticks and increased blinking has a high probability (93% sensitivity and 90% specificity) of differentiating Benign Essential Blepharospasm (BEB) from other similar disorders.
Patients with blepharospasm frequently report other non-motor symptoms like mental health disorders, sleep disorders, sensory symptoms, and cognitive disturbances. Sensations like eye dryness or sensitivity to light are also common among those with BEB.
To gauge the intensity of the disease, doctors employ various measures. The most common is the Jankovic Rating Scale, used to monitor a patient’s progress and response to treatment. It rates both the severity and the frequency of the spasms, assigning a score of 0-4 for each category.
The diagnosis also involves a few neurological tests. The contraction of muscles that oppose one another signifies dystonia, a key feature of blepharospasm. This can be detected using an electromyography. However, this test isn’t practical for everyone.
The blink reflex evaluation, which assesses your ability to control the urge to blink when a light tap is applied on your forehead, can also be relevant. Other methods to trigger the blink reflex involve sudden visual or auditory stimuli. Although largely used for research, these tests can help rule out psychogenic dystonia, which exhibits normal features.
Treatment Options for Benign Essential Blepharospasm
While we don’t fully understand what causes benign essential blepharospasm (a condition that makes your eyelids involuntarily blink or spasm), there are several treatments available.
For instance, there’s a form of treatment known as Photochromatic Modulation. This involves using tinted lenses to block specific wavelengths of light, which can help manage the symptoms of light sensitivity in people with this condition. Research has shown that a particular type of tint called FL-41 can significantly reduce symptoms of light sensitivity in these patients.
Another common treatment is injections of Botulinum Toxin, which you might know as Botox. This toxin actually comes in seven different forms, but in America, only the A and B versions are used for this condition. These injections work by preventing certain chemicals from being released in your eye muscles, which helps reduce muscle contraction and control the eyelid spasms.
The procedure to administer these injections is fine-tuned and precise. One injection typically contains about 1.25-5 units of Botulinum Toxin, but some recipients may need larger doses over time. It generally takes about 48 hours for the effects of the injection to take hold, reducing abnormal eye movements. However, each person’s response varies, and results can last up to 170 days.
While unwanted side effects are possible, they are often linked to poor injection techniques or the body’s production of antibodies against the toxin. Generally, these injections are given every three to four months, although some people report that effectiveness decreases after the first round.
Oral Pharmacotherapy – medications taken by mouth – have also been used to treat this condition, but they haven’t consistently relieved symptoms. These medications can potentially cause unwanted side effects and may lead to dependency, so they’re usually reserved for cases that have not responded to other treatments.
Finally, if the condition does not improve with medical treatment, surgery may be considered. This can involve removing or modifying certain eye muscles to reduce the frequency of spasms. This approach can bring significant improvement, but some patients may still require Botox injections after surgery – albeit at lower doses.
Deep brain stimulation is a more invasive surgical treatment and is generally considered a last resort.
What else can Benign Essential Blepharospasm be?
Blepharospasm Essentiale Benigne (BEB) is a condition that can easily be confused with other conditions because of their similar symptoms. So, it is crucial to differentiate between these health problems and understand their differences.
Firstly, there’s Apraxia of Eyelid Opening (AEO), commonly seen in individuals with motor disorders. Interestingly, AEO can sometimes occur in healthy people. It shares a lot of characteristics with BEB, like a higher occurrence rate in women and older individuals, and can often coexist with BEB in many instances.
Another condition to consider is Hemifacial Spasm, characterized by uncontrolled muscle twitches on one side of the face. Usually, these spasms are triggered by facial movements, stress, or changes in head position. Interestingly, these spasms can sometimes be alleviated by relaxation techniques, touching the affected area, or even consuming alcohol.
Following a facial nerve paralysis event, something called Post-Facial Palsy Synkinesis can happen. This can lead to unexpected muscle movements on the face, such as involuntary eye closure when moving the mouth, or unintended mouth movements when moving the eyes.
Then there’s Psychogenic Facial Spasm, typically observed in younger individuals around 34 years of age. Stress and anxiety commonly trigger it, and the spasms can be reduced when the patient focuses on another task.
Facial Motor Tics are short, sudden muscle contractions that resemble normal, voluntary movements. Generally, patients with these tics feel an overwhelming need to perform the movement but can resist and suppress them if they try.
Another condition to differentiate is Facial Myokymia, typically associated with lack of sleep, too much caffeine, and severe tiredness. This is usually a fleeting condition but may require treatment in some cases.
Lastly, Tardive Dyskinesia can produce involuntary, repetitive movements around the mouth and eyes. It could potentially manifest after long-term use of certain psychiatric drugs.
Understanding these various conditions will greatly aid in ruling out BEB, ensuring accurate diagnoses and effective treatments.
What to expect with Benign Essential Blepharospasm
Having isolated BEB, or Benign Essential Blepharospasm, doesn’t seem to reduce a person’s lifespan, but it can significantly impact their quality of life. In a study of 238 patients with BEB or Meige syndrome, it was discovered that about 11.3% (27 patients) saw their symptoms naturally disappear, leading to a good quality of life.
However, most patients continuously worry about the progression of their symptoms, and sometimes even need to increase their doses of botulinum toxin (or botox) for their symptoms to improve. If the disease continues to worsen, botox injections may no longer help. Because of these difficulties, people with BEB often feel insecure and embarrassed, particularly in social situations, which could make them avoid social activities.
Possible Complications When Diagnosed with Benign Essential Blepharospasm
Injecting Botulinum toxin could possibly lead to several complications. These could range from ptosis (a condition where your upper eyelids fall), diplopia (a vision problem where you see two images of a single object), photophobia (sensitivity to light), ecchymosis (bruises), epiphora (excessive tearing), and blurred vision, among others. However, it’s important to note that the risk of these complications decreases with each subsequent injection.
The most commonly reported side effect is ptosis. This may happen if the toxin accidentally reaches the levator palpebrae superioris muscle, which controls the lifting of the eyelid. Studies have shown that the chances of developing ptosis after a botulinum injection can range from about 5.88% to 20%. This difference is mainly due to variations in the injection technique and the amount of toxin used. To minimize the risk of ptosis, it’s recommended to avoid the center of the eyelid when injecting the toxin.
Botulinum Toxin Injection Side Effects:
- Ptosis (drooping of the eyelid)
- Diplopia (double vision)
- Photophobia (light sensitivity)
- Ecchymosis (bruising)
- Epiphora (excessive tearing)
- Blurred vision
A weakened orbicularis oculi muscle, which controls the closing of the eyelid, could result in lagophthalmos which might lead to dry eye and exposure keratitis (a condition where the surface of your eye gets inflamed).
The injection could also affect patients with blepharospasm, a condition where your eyelids close or blink uncontrollably, as they often have difficulty in opening their eyelids. These patients may need injections into their orbicularis oculi muscle and are advised to apply a lubricating ointment in their eyes for about two to three weeks after injections. They are also recommended to increase the usage of topical eye lubrications for that period. This is because Botulinum toxin injection has been found to slow lacrimal drainage (draining of tears), due to a slower blink rate and laxity (looseness) of the lower eyelid caused by paralysis of the lacrimal section of the orbicularis oculi muscle.
