Blepharospasm

Focal dystonia appearing in adults with recurrent spasms of eye closure; the orbicularis oculi muscle contracts forcibly and involuntarily. This lasts for periods varying from seconds to minutes and often repeatedly. Occasionally, this can be so frequent as to make the patient effectively blind.

Most cases are idiopathic and termed benign essential blepharospasm or primary blepharospasm. There are cases of secondary blepharospasm due to identifiable organic disease, listed below:

• Multiple sclerosis (may cause blepharoclonus - prolonged, severe and painful eyelid closure)¹
• Focal brain injury, particularly of the basal ganglia
• Atypical Parkinson's Disease/Multi-System Atrophy/progressive supranuclear palsy
• Adverse drug reactions, eg olanzapine,² tardive dyskinesia
• Tourette's Syndrome
• Cerebral palsy
• Familial cases³

Estimated at 16 to 133 per million.⁴

Symptoms

• Spasms of eye closure usually occur in bright light, or when reading or watching television
• Fatigue or emotional tension can also worsen the symptoms
• Concentration on a task, or being observed may improve or abate the symptom, or reduce its frequency
• Nocturnal symptoms are unusual

• Untreated, the condition can cause severe psychological distress and is associated with significant psychiatric co-morbidity.⁵
• Condition linked with an oromandibular dystonia characterised by recurrent spasms of face, oropharynx, larynx. This causes spasms of lip and jaw movement, chin jutting and problems with speaking and swallowing.
• Patients may develop oromandibular dystonia after blepharospasm and vice versa.
• Where blepharospasm is the main feature this is called Meige syndrome.

General Measures

• Wearing dark glasses can reduce bright light triggers and prevent embarrassment due to the stares of onlookers.
• Voluntary manoeuvres such as pulling the eyelid, pinching the neck, talking, yawning, humming and singing help some sufferers.⁶

Drugs

• Does not respond well to antispasmodics or benzodiazepines.
• Tetrabenazine has been shown to be of moderate benefit in some patients.⁷
• Preferred treatment is injection of Botulinum toxin type A into the orbicularis oculi muscle. A recent Cochrane systematic review found the treatment to be highly effective, helping up to 90% of patients compared to placebo. More research is needed to determine optimal treatment schedules, injection techniques and long-term safety.^8,9 Repeat injection is currently given after a period of 3-6 months.

Surgery

Where vision is severely impaired by prolonged, severe eye closure, unresponsive to pharmacological techniques, protractor myomectomy may be used (removal of some muscles of eye closure). Its use should be carefully considered as a last resort.