Botulinum toxin therapy of dystonia

Abstract

Botulinum toxin (BT) is used to treat a large number of muscle hyperactivity syndromes. Its use in dystonia, however, is still one of the most important indications for BT therapy. When BT is injected into dystonic muscles, it produces a peripheral paresis which is localised, well controllable and follows a distinct and predictable time course of around 3 months. Adverse effects are always transient and usually mild, long-term application is safe. With this profile BT can be used to treat cranial dystonia, cervical dystonia and limb dystonia including writer’s and musician's cramps. The recent introduction of BT high dose therapy also allows to treat more wide-spread dystonia including segmental and generalised dystonia. BT can easily be combined with other anti-dystonic treatments such as deep brain stimulation and intrathecal baclofen application. Best treatment results are obtained when BT therapy is integrated in the multimodal and long-term 'multilayer concept of treatment of dystonia'. The biggest challenge for the future will be to deliver state of the art BT therapy to all dystonia patients in need, regardless of whether they live in developed countries or beyond.

The Central Effects of Botulinum Toxin in Dystonia and Spasticity

“…4 weeks after application and slowly wears off as the neuromuscular junction recovers within 12 weeks [ 2 , 3 ]. Thanks to the long-lasting effect and good safety profile, intramuscular injections of BoNT-A have become the first-line treatment for focal spasticity [ 4 , 5 , 6 ] and dystonia [ 7 ]. Although, in general, clinical improvement usually follows the time course of the peripheral changes, there are a number of reports of discrepancies between the clinical symptoms and the duration or degree of neuromuscular junction blockade [ 3 ].…”

Spectrum of Botulin toxin

“…Doses range between 20-40 MU of ONA are used. 4 Focal dystonia is a common, invalidating neurologic condition characterized by involuntary, sustained muscle contractions causing twisting movements and abnormal postures in one body part. Local injections with Botulinum toxin A (BTX A) are safe and effective in the treatment of focal dystonia.…”

“…3. Group III -can produce toxins C or D. 4. Group IV -can produce toxin G (does not cause neuroparalytic illness).…”

The Impact of the Course of Disease before Botulinum Toxin Therapy on the Course of Treatment and Long-Term Outcome in Cervical Dystonia

“…Since CD is a long-term disease, it requires long-term treatment [ 7 ]. Repetitive intramuscular injections of botulinum toxin (BoNT) every 10 to 16 weeks have become treatment of choice for this chronic neurological disorder [ 3 , 7 , 10 , 11 ].…”