Botulinum Toxin Treatment of Blepharospasm, Orofacial/Oromandibular Dystonia, and Hemifacial Spasm

Abstract

Blepharospasm is a focal dystonia characterized by involuntary, repetitive eye closure. Orofacial and oromandibular dystonia describe involuntary dystonic movements of orofacial and oromandibular musculature. Hemifacial spasm is characterized by repetitive synchronous contraction of facial nerve innervated muscles on one side of the face. In this article, the clinical presentation, epidemiology, and approaches to treatment are reviewed. Technical aspects of using botulinum toxin for treatment and reported outcomes are discussed.

History of Botulinum Toxin Treatment in Movement Disorders

“…In the most recent review of botulinum toxin treatment of blepharospasm, Karp and Alter17 define botulinum toxin as the first line of treatment for blepharospasm with an efficacy rate of over 90% based on the accumulative literature. Botulinum toxins are effective in both essential and secondary blepharospasm.…”

“…Botulinum toxins are effective in both essential and secondary blepharospasm. Experience of up to 26 years has demonstrated continued efficacy with repeated injections, although a small increase in the dose may be necessary over time to maintain the same level of efficacy 17,18. The most recent guidelines of American Academy of Neurology19 assigns level B evidence (probably effective) to incobotulinumtoxinA and onabotulinumtoxinA toxins and a level C evidence (possibly effective) to abobotulinumtoxinA for treatment of blepharospasm.…”

“…In most cases, the cause is an anomalous and ectatic blood vessel that impinges upon the facial nerve as it exits from the brain stem. Treatment with anticonvulsants and clonazepam can be partially effective 17. Neurovascular decompression is effective in most cases, but in some cases it can cause serious morbidity.…”

Olfaction as a Marker for Dystonia: Background, Current State and Directions

“…Injections of botulinum toxin into muscles affected by dystonia is a well-established and very effective treatment [ 61 , 187 , 188 , 189 ]. To the best of our knowledge, effects of botulinum toxin on the chemical sense by comparing performance in tests of the chemical senses before and after injections of botulinum toxin have not been systematically assessed in subjects with dystonia.…”

History of Botulinum Toxin Treatment in Movement Disorders

“…Experience of up to 26 years has demonstrated continued efficacy with repeated injections, although a small increase in the dose may be necessary over time to maintain the same level of efficacy. 17,18 The most recent guidelines of American Academy of Neurology 19 assigns level B evidence (probably effective) to incobotulinumtoxinA and onabotulinumtoxinA toxins and a level C evidence (possibly effective) to abobotulinumtoxinA for treatment of blepharospasm. It states, however, that in view of most experts in the field of movement disorders, botulinum toxins are considered the first line of treatment for blepharospasm.…”