12-year effectiveness and safety of botulinum toxin type A for the treatment of blepharospasm and hemifacial spasm

Objective:The objective of this study was to perform a long-term evaluation of the efficacy and safety of treatment with botulinum toxin A (BoNT-A) in patients with blepharospasm (BS) and hemifacial spasm (HFS) from January 2007 to December 2019.Methods: In each application of BoNT-A, the date of treatment, number of units applied, and time elapsed since the previous application were recorded.Outcome data was: mean latency of the clinical effect, mean duration of the clinical effect, mean improvement on Jankovic rating scale, side effects were self-reported, and evaluated 2 weeks after injection, including non-responding patients to BoNT-A for two consecutive sessions.The comparison between the first and last dose of BoNT-A was analyzed by Student's t-test, for which a value of p < 0.05 was considered statistically significant.Results: A total of 136 patients were analyzed; 60 had BS, 76 had HFS, and 75% were female.The duration between onset and referral for BoNT-A treatment was 18 ± 3 months, and the mean age at the time of the first therapeutic injection was 50 ± 12 years.The mean dose per session was 16 ± 4 for BS and 36 ± 12 for HFS.The therapeutic interval for injections was 4.4 ± 1 month.The mean latency of the clinical effect was 8 ± 3 days, the mean duration of the clinical effect was 112 ± 9 days, and the mean improvement on the Jankovic scale was 2 ± 1 points.Side effects were observed in 9 patients (6.6%), that is, ptosis (7 patients) and hematoma (2 patients).Conclusions: BoNT-A is a safe and effective long-term treatment for BS and HFS.