Meige's syndrome: History, epidemiology, clinical features, pathogenesis and treatment.

'Meige's syndrome' is a type of cranial dystonia characterized by blepharospasm and oromandibular dystonia and can be associated with complex movement of lower facial muscles, mouth, jaw, tongue, pharyngeal and cervical muscles. Frequently, blepharospasm is the earliest clinical manifestation, which spreads over a period of time to involve other cranial and extra-cranial muscles. Common characteristics of this syndrome are well known, but their variety is wide. Different eponyms such as "Breughel syndrome", "Wood syndrome", "Blepharospasm plus", "Segmental cranial dystonia" and "Segmental cranio-cervical dystonia" have been used to describe this entity with numerous anatomical variations. In the majority of the patients Meige's syndrome is primary or idiopathic, where the cause of spasm is not known, however secondary cases can occur following prolonged use of neuroleptics or secondary to underlying brain disorders. This syndrome has also been described in patients with essential tremor, Parkinson's disease and atypical Parkinsonism. Neurophysiological features are similar to other focal dystonia characterized by abnormal plasticity and impaired inhibition. Most of the patients are successfully treated with injection of botulinum toxin, however deep brain stimulation has emerged as a good therapeutic option in intractable patients. The objective of this review is to understand whether patients who develop Meige's syndrome are different from patients who manifest blepharospasm or oromandibular dystonia alone.