Blepharospasm

Blepharospasm
Classification and external resources

Left orbicularis oculi, seen from behind.
ICD-10 G24.5
ICD-9 333.81
DiseasesDB 15748
eMedicine oph/202
MeSH D001764

A blepharospasm (from Greek: blepharo, eyelid, and spasm, an uncontrolled muscle contraction), is any abnormal contraction or twitch of the eyelid.

It normally refers to benign essential blepharospasm, a focal dystonia—a neurological movement disorder involving involuntary and sustained contractions of the muscles around the eyes. Essential indicates that the cause is unknown, but fatigue, stress, or an irritant are possible contributing factors. In most cases, symptoms last for a few days then disappear without treatment, but sometimes the twitching is chronic and persistent, causing lifelong challenges. In those rare cases, the symptoms are often severe enough to result in functional blindness. The person's eyelids feel like they are clamping shut and will not open without great effort. Patients have normal eyes, but for periods of time are effectively blind due to their inability to open their eyelids.

Although strides have recently been made in early diagnosis, blepharospasm is often initially mis-diagnosed as allergies or "dry eye syndrome". It is a fairly rare disease, affecting only one in every 20,000 people in the United States.

Contents

Symptoms

Causes

Some causes of blepharospasm have been identified; however, the causes of many cases of blepharospasm remain unknown, although some educated guesses are being made. Some blepharospasm patients have a history of dry eyes and/or light sensitivity, but others report no previous eye problems before onset of initial symptoms. Recent research suggests quite a strong link with cases of syphilis (Hardmann and Jean, 2010), however this is yet to be confirmed.

Some drugs can induce blepharospasm, such as those used to treat Parkinson's disease, as well as sensitivity to hormone treatments, including estrogen-replacement therapy for women going through menopause. Blepharospasm can also be a symptom of acute withdrawal from benzodiazepine dependence. In addition to blepharospasm being a benzodiazepine withdrawal symptom, prolonged use of benzodiazepines can induce blepharospasm and is a known risk factor for the development of blepharospasm.[2]

Blepharospasm may also come from abnormal functioning of the brain basal ganglia. Simultaneous dry eye and dystonias such as Meige's syndrome have been observed. Blepharospasms can be caused by concussions in some rare cases, when a blow to the back of the head damages the basal ganglia.

Treatment

See also

References

  1. ^ Adams WH, Digre KB, Patel BC, Anderson RL, Warner JE, Katz BJ (July 2006). "The evaluation of light sensitivity in benign essential blepharospasm". American Journal of Ophthalmology 142 (1): 82–87. doi:10.1016/j.ajo.2006.02.020. PMID 16815254. 
  2. ^ Wakakura M, Tsubouchi T, Inouye J (March 2004). "Etizolam and benzodiazepine induced blepharospasm". Journal of Neurology, Neurosurgery, and Psychiatry 75 (3): 506–7. doi:10.1136/jnnp.2003.019869. PMC 1738986. PMID 14966178. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1738986. 
  3. ^ Schellini SA, Matai O, Igami TZ, Padovani CR, Padovani CP (2006). "Blefarospasmo essencial e espasmo hemifacial: características dos pacientes, tratamento com toxina botulínica A e revisão da literatura [Essential blepharospasm and hemifacial spasm: characteristic of the patient, botulinum toxin A treatment and literature review]" (in Portuguese). Arquivos Brasileiros De Oftalmologia 69 (1): 23–6. doi:10.1590/S0004-27492006000100005. PMID 16491229. 
  4. ^ Anderson RL, Patel BC, Holds JB, Jordan DR (September 1998). "Blepharospasm: past, present, and future". Ophthalmic Plastic and Reconstructive Surgery 14 (5): 305–17. doi:10.1097/00002341-199809000-00002. PMID 9783280. 

External links