[Progression of botulinum toxin type A dosage in craniocervical dystonias. An eight year comparative study].

INTRODUCTION

Botulinum toxin type A (BTA) is currently the choice treatment for focal dystonias; yet long term response to therapy is still not known with total accuracy.

PATIENTS AND

METHODS

In this study we analysed the dose of BTA used in the first eight years' treatment of 17 patients with cervical dystonia and 16 patients with blepharospasm who received treatment at our hospital.

RESULTS

It was found that in the patients with cervical dystonia there was a significant increase in the dosage of BTA (41%) which rose in a linear fashion from the fourth year onwards. On the other hand, in the group of patients with blepharospasm, the dosage of BTA tended to drop with time and this reduction (16%) occurred essentially during the first four years of treatment.

CONCLUSIONS

These findings clearly highlight the clinical and functional differences between the two types of craniocervical dystonia.