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Blepharospasm is a typical ocular disorder that results in functional blindness in the absence of prompt treatment. Read on to find out about the causes, symptoms, diagnosis and treatment of this condition.
The disorder is characterized by involuntary, forcible closure of the eyelids. A normal adult blinks at a rate of 10 to 20 times per minute. In this condition, however, there is an abnormal increase in the frequency of eyelid twitching. It is generally referred to as “benign essential blepharospasm”, which describes the condition as repeated, involuntary contractions of the muscles around the eyes.
The condition does not carry any early warning signs and may initially begin with mild involuntary blinking. The characteristic symptom is frequently experienced by the patients, but not noticeable by others. Blinking of the eyelid occurs every few seconds over the course of a minute or two. The frequency of eye blinking gradually increases and develops into ocular irritation. A wide variety of stimuli comprising of wind, pollutants, light, emotional tension, noise and environmental stress can aggravate the problem. High level of discomfort arises when patients have to experience the following symptoms:
Picture 1 – Blepharospasm
- Dry eyes
- Abnormal intolerance to sun and bright light, called Photophobia
- Sudden contraction of the ocular muscles when reading, walking, driving or watching television
- Twitching of the facial muscles
- Radiation of twitching sensations to the nose, face and neck region
- Eyebrow twitching
- Mid-facial or lower facial spasm
- Excess of skin in the upper or lower eyelid
- Inward folding of the eyelids, resulting in constant rubbing of the eyelashes against each other
However, patients may experience temporary relief from the distressful symptoms through activities like:
- Constant gazing
- Touching the face
The condition may arise spontaneously without any valid cause. In fact the term “benign essential blepharospasm” indicates that most cases of the non-fatal disorder are idiopathic. Individuals with a history of dry eyes or photophobia could be more prone to uncontrolled ocular muscle contraction. Following are some of the identifiable causes of the condition:
It is a sexually transmitted disease caused by Treponema pallidum, a spirochete bacterium. The microorganism attacks the body by directly burrowing into the moist mucous membranes of the mouth or genitals. Although most cases of the contagious disease resolve on its own, the remaining ones proceed to the next stage. It is only in the tertiary stage when the infection causes extensive damage to the brain, causing twitching of the ocular muscles.
The etiologic factors involved in inflicting injury to the eyes can be divided into the following:
Chemical irritants like acids, aerosols, soap or harmful gases can result in severe damage to the eyes.
Any damage to the conjunctiva can cause accumulation of blood on the white surface of the eye. A slight scratch or defect in the cornea can affect the normal functioning of the eyes. Fractures of the facial bones surrounding the eye can affect the ocular muscles. Presence of a foreign body in the eye such as a small piece of metal, wood, or plastic can give rise to severe discomfort and damage.
In many cases, the eye may get subjected to light induced trauma such as Ultraviolet keratitis. Welding arcs, tanning beds and sunlight reflected by water or snow are some of the common sources of ultraviolet light.
It is a neurodegenerative disorder marked by progressive loss of muscle control, which results in trembling of the limbs and head. The impairment can be owed to the lack of a chemical called dopamine, which acts as a messenger between two regions of the brain, substantia nigra and corpus striatum. Deficiency of the substance can lead to loss of control of eye movements.
Chronic inflammation of the eyelids can result in irritation and constant twitching of the affected eye/eyes.
This is an unusual type of ocular disease in which the eyelashes grow back towards the eye and touch the cornea or conjunctiva. Frequent episodes of blinking form the predominant hallmark of the condition.
Ocular surface disease
Inflammation of the conjunctiva due to an infection or allergy is one of the primary reasons for eye blinking.
Chronic lid disorder
An array of conditions may directly affect the eyelid. Some of these include:
- Eyelid edema/tumors
- Drooping eyelids
It is an inflammatory condition of the uvea, an inner layer of the eye comprising of the iris, blood vessels, and the ciliary body and the choroid.
It refers to the damage of the optic nerve, which carries impulses from the retina to the brain for formation of images. In this disorder, patients experience eye pain, visual disturbances and repeated closure of the eyelids.
This hereditary neurological disorder is commonly observed in early childhood and characterized by sudden, repetitive movements of muscles called tics. Facial grimacing, visual problems, head jerking as well as eye blinking are some of the common examples of tics.
Focal brain injury
Involuntary spasms of the eyelid muscles can be attributed to malfunctioning of the basal ganglia, a region of the base of the brain consisting of cluster of neurons. The basal nuclei are responsible for controlling eye movements and motor control. Focal injuries normally occur in this region of the brain. Such traumatic injuries are an outcome of direct mechanical forces, for example, striking the head with a blunt object.
Progressive supranuclear palsy
The rare degenerative disease of the brain impairs the normal movement and balance of the body. The condition produces visual symptoms like slowing of speech, difficulty swallowing, stiffening of neck, and poor eyelid function.
Multiple system atrophy
It is a neurological disorder in which degeneration of nerve cells in certain areas of the brain causes uncoordinated muscular movement and imbalance.
Degeneration of the nerves of the brain and spinal cord affects the different functions of the nervous system such as speech, walking, memory and vision.
Adverse drug interactions
Several prescription drugs, like Reglan, can affect the pathways of the neurotransmitter called dopamine, causing uncontrolled ocular muscle contraction. Visual problems are common due to forced closure of the eyelids.
Blinking is a physiologic response, involving the relaxation of the levator muscle, responsible for opening the eyelids with simultaneous contraction of the palpebral portion of the orbicularis oculi muscle, a ring-like band of muscle helping in closing the eyelids. Blinking can be spontaneous, reflex or voluntary. A blinking center located in the lenticular nucleus, which comprises of the putamen and the globus pallidus within the basal ganglia of the brain, controls the rapid closing and opening of the eyes under normal circumstances. Dopamine aids in the functioning of the ocular muscles. However, in this condition excessive release of dopamine causes spontaneous eye blinking.
Physical evaluation of the affected eye may help in spotting any underlying structural abnormality causing the disorder. A drop of special dye or stain called fluorescein is placed into the affected area for lubrication of the eye. Presence of ocular abrasions becomes more obvious when a blue light is thrown over the eye. The other tests that are commonly used include:
In this method, a low-power microscope combined with a high-intensity light source is used for examining the front portions of the eye, including the cornea and iris, for any infection.
Special types of blood tests are used to diagnose syphilis. The diagnostic procedures that are followed detect the body’s response to the infection. An inflammatory condition of the eye due to a bacterial infection is evident from a high white blood cell count.
The test is essential for detecting orbital fracture and ocular foreign bodies.
The procedure involves the assessment of the sensory neurons and motor reflexes by conducting a thorough physical examination, and detailed study of the medical history of a patient. The technique is useful in finding out any underlying neurodegenerative disorders.
The condition of the optic nerve can be properly examined using an ophthalmoscope, a device equipped with a concave mirror and a battery-powered light. Glaucoma-affected patients usually display an indented optic disc as a consequence of increased intraocular pressure.
Magnetic resonance imaging, computerized tomography, and electroencephalogram may aid in the diagnosis of focal brain injuries, cerebral lesions and progressive supranuclear palsy.
Blepharospasm Differential Diagnosis
Differential diagnosis of the condition essentially involves ensuring the absence of a number of conditions that are present with similar symptoms. These are:
- Eyelid Myokymia
- Facial paralysis
- Sjogren syndrome
Although there are several treatment options available, the disorder has no permanent cure. Some of these are:
The efficacy of the drugs used in this condition is normally temporary and may not yield results in some cases. A dietary supplement of magnesium chloride has proved to be beneficial in some patients.
Botulinum toxin injections
The therapeutic agent partially paralyzes the ocular muscles and prevents the repetitive movements of the affected eye. Botulinum toxin is administered every three months as its effects do not last for a long time. Most patients get quick relief from eye twitching and are able to lead a normal life.
Doctors may have to opt for a surgery if patients show signs of visual impairment and do not respond to other treatments. Protractor myectomy, which involves the partial or complete excision of the muscles responsible for closure of the eyelid, is the most successful surgical intervention for the disorder.
Remission of the symptoms can be achieved up to a certain degree by regular massaging and relaxation of facial and jaw muscles.
While traveling, affected individuals can wear dark glasses in order to prevent the eyes from getting affected by the bright light. It is possible to cope with the disorder by following some proper stress management techniques.
Untreated cases can evolve into complications like:
Picture 2 – Blepharospasm Image
- Segmental dystonia
- Pulling sensation behind the eyes
- Partial vision loss
Blepharospasm Support Groups
The Blepharospasm Bulletin Board, which is sponsored by the Benign Essential Blepharospasm Research Foundation, provides an online platform for the sufferers to discuss their problems. Family members of the patients can also seek useful advice and support from various healthcare providers who are a part of the group.
Blepharospasm is a lifelong disorder and only less than 3% of all patients get completely rid of the symptoms. However, with Botox therapy the episodes of spontaneous blinking get successfully reduced. Comprehensive assessment should be immediately carried out in case, an individual displays abnormal twitching of the eyelid.