[Long-term evolution of the doses of Botulinum toxin used in laryngeal and cervical dystonias]. / Evolución a largo plazo de la dosis de toxina botulínica en las distonías laringea y cervical

INTRODUCTION: Dystonia is a neurological condition characterised by involuntary movements that give rise to abnormal postures. Different strategies have been used in the treatment of focal dystonias, but the most widely accepted at the present time involves the use of botulinum toxin type A (BTA) injections. Yet, despite its widespread use, the ideal dosages for long-term treatment are still not known with precision. AIMS: The purpose of this study is to report on our experience with long-term BTA therapy in laryngeal (LD) and in cervical dystonia (CD). PATIENTS AND METHODS: We reviewed the data concerning the dosages of BTA injected in 10 patients with LD who received treatment in our centre over a period of eight years. We also analysed the data regarding the doses of BTA injected over an eight-year period in 17 patients with CD. The data were analysed using an ANOVA for paired data. RESULTS: No significant differences were found in the highest dosages of BTA needed for the treatment of LD throughout the progression of the disease (p=0.84). These data contrast with those obtained from the analysis of the treatment of CD, which do show a gradual increase in the dose of toxin that is required (p<0.0001). CONCLUSIONS: These findings suggest that the long-term response to treatment is different in the two conditions.

[Progression of botulinum toxin type A dosage in craniocervical dystonias. An eight year comparative study]. / Evolucion de la dosis de toxina botulinica tipo A en distonias craneocervicales. Estudio comparativo a lo largo de ocho años.

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.

Evolución de la dosis de toxina botulínica tipo A en distonías craneocervicales. Estudio comparativo a lo largo de ocho años / Progression of botulinum toxin type a dosage in craniocervical dystonias. An eight-year comparative study

Introducción. En la actualidad, la toxina botulínica de tipo A (TBA) es el tratamiento de elección de las distonías focales; sin embargo, no se conoce con precisión la respuesta al tratamiento a largo plazo. Pacientes y métodos. En este estudio analizamos la dosis de TBA utilizada en los ocho primeros años de tratamiento de 17 pacientes con distonía cervical y 16 pacientes con blefaroespasmo tratados en nuestro hospital. Resultados. Observamos que en los pacientes con distonía cervical se produjo un incremento significativo de la dosis de TBA, del 41 por ciento que ocurre de forma lineal solamente a partir del cuarto año. En contraste, la dosis de TBA en el grupo de pacientes con blefaroespasmo tiende a reducirse con el tiempo, y esta reducción, del 16 por ciento, se produce fundamentalmente en los cuatro primeros años de tratamiento. Conclusión: Estos resultados reflejan claramente las diferencias clínicas y funcionales de estos dos tipos de distonía craneocervical (AU)

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 (AU)