Treatment of hemifacial spasm with botulinum toxin type a: effective, long lasting and well tolerated.

Objective To evaluate the long-term effect of botulinum toxin type A (BTX-A) in the treatment of HFS. Methods A retrospective analysis of patients treated at the Movement Disorders Outpatient Clinic in the Neurology Service, Hospital de Clínicas, Federal University of Paraná, Curitiba, from 2009 to 2013 was carried out. A total of 550 BTX-A injections were administered to 100 HFS patients. Results Mean duration of improvement following each injection session was 3.1 months, mean latency to detection of improvement was 7.1 days and mean success rate was 94.7%. Patients were evaluated at an interval of 5.8 months after each application. Adverse effects, which were mostly minor, were observed in 37% of the patients at least once during follow-up. The most frequent was ptosis (35.1%). Conclusion Treatment of HFS with BTX-A was effective, sustainable and safe and had minimal, well-tolerated side effects.