RESUMO
OBJECTIVES: Vocal tremors, which cause social difficulties for patients, may be classified as resting or action tremors. Of the vocal action tremors, essential and dystonic tremors are the most common. Botulinum toxin and oral medications have been used to treat vocal tremors, but no comparative clinical trials have been performed. The aim of this study was to compare the effects of botulinum toxin injection and the oral administration of propranolol in the treatment of essential and dystonic vocal tremors. METHODS: This clinical trial recruited 15 patients, divided into essential and dystonic vocal tremor groups. Patients in both groups received successive treatment with botulinum toxin and propranolol. The treatments were administered at different times; the order of treatment was randomly selected. Patients were assessed with flexible nasofibrolaryngoscopy and with perceptual and acoustic voice evaluations. A statistical significance level of 0.05 (5%) was used. RESULTS: Botulinum toxin produced statistically significant improvements in perceptual measures of vocal instability in patients with dystonic vocal tremors compared with baseline values and treatment with propranolol. The acoustic measure of variability in the fundamental frequency was significantly lower in patients with dystonic vocal tremors after treatment with botulinum toxin. CONCLUSION: Essential and dystonic vocal tremors responded differently to treatment. Dystonic vocal tremors responded significantly to treatment with botulinum toxin but not oral propranolol. Essential vocal tremors did not respond significantly to either treatment, perhaps due to the small number of patients, which is a limitation of this research.
Assuntos
Humanos , Propranolol/administração & dosagem , Distúrbios da Voz/tratamento farmacológico , Agonistas Adrenérgicos beta/administração & dosagem , Toxinas Botulínicas Tipo A/uso terapêutico , Distúrbios Distônicos/tratamento farmacológico , Músculos Laríngeos/efeitos dos fármacos , Fármacos Neuromusculares/administração & dosagem , Propranolol/uso terapêutico , Tremor/tratamento farmacológico , Reprodutibilidade dos Testes , Resultado do Tratamento , Estatísticas não Paramétricas , Eletromiografia , Injeções IntramuscularesRESUMO
The stereotactic surgical target for dystonic tremor is the subject of ongoing debate. Targeting the subthalamic area using deep brain stimulation has been regaining interest as a therapy for various types of involuntary movements. We describe the efficacy of stimulation of the subthalamic area in a patient with intractable dystonic tremor. Excellent control without neurological complications was achieved. This case report demonstrates that the subthalamic area is a valuable target for the control of dystonic tremor.