RESUMO
BACKGROUND: Rare information exists about comparative long-term observations of patients with facial movement disorders. This retrospective analysis deals with the course of different parameters of injection over the time. METHODS: In this study we compared the development of long-term botulinum toxin treatments of patients with blepharospasm, hemifacial spasm and synkinesis. 80 patients (n=30 blepharospasm, n=31 hemifacial spasm, n=19 synkinesis), who had at least 10 consultations for BTA-injections, were included in the retrospective analysis. The development for each entity in total dosage, increase in the number of injection points and change in dosages for each point were evaluated. RESULTS: The over-all dosage in all 3 clinical disorders and for each single disease itself increased continuously over the time. The amount of injection points increased in the treatment of hemifacial spasm and synkinesis. The dosage per point increased most in blepharospasm between the 1. and 25. injection, but was distinctly lower in patients with hemifacial spasm and synkinesis. The increase in dosage in blepharospasm is therefore, in contrast to the other indications, mostly caused by an increase in dosage per point. In patients with hemifacial spasm and synkinesis the escalation of dosage is mainly caused by an increase of the number of injection points. CONCLUSION: These new aspects of the dynamic in the treatment with botulinum toxin enable the physician to understand better the dynamic of these diseases, to optimize treatment protocols.