Differences in improvement between patients with idiopathic versus neurovascular hemifacial spasm after botulinum toxin treatment.

This study was performed to investigate the differences in response to botulinum toxin treatment between patients with idiopathic versus neurovascular hemifacial spasm. A total of 69 patients with hemifacial spasm were investigated prospectively with cranial magnetic resonance imaging and magnetic resonance angiography. Neurovascular contact was found in 23 patients. All patients were assessed with a severity scale and a disease awareness scale. After treatment, the patients with idiopathic hemifacial spasm improved significantly in terms of both severity and awareness scores, but the patients with neurovascular hemifacial spasm improved only in the awareness scores. In conclusion, patients with idiopathic hemifacial spasm experienced a greater improvement after treatment with botulinum toxin than did patients with neurovascular hemifacial spasm.