Long-term efficacy of botulinum toxin A for treatment of blepharospasm, hemifacial spasm, and spastic entropion: a multicentre study using two drug-dose escalation indexes

Abstract

Purpose To investigate the long-term effectiveness and safety of botulinum neurotoxin A (BoNT-A) treatment in patients with blepharospasm (BEB), hemifacial spasm (HFS), and entropion (EN) and to use for the first time two modified indexes, 'botulin toxin escalation index-U' (BEI-U) and 'botulin toxin escalation index percentage' (BEI-%), in the dose-escalation evaluation. Methods All patients in this multicentre study were followed for at least 10 years and main outcomes were clinical efficacy, duration of relief, BEI-U and BEI-%, and frequency of adverse events. Results BEB, HFS, and EN patients received a mean BoNT-A dose with a significant intergroup difference (Po0.0005, respectively). The mean ( ± SD) effect duration was statistically different (P ¼ 0.009) among three patient groups. Regarding the BoNT-A escalation indexes, the mean ( ± SD) values of BEI-U and BEI-% were statistically different (P ¼ 0.035 and 0.047, respectively) among the three groups. In BEB patients, the BEI-% was significantly increased in younger compared with older patients (P ¼ 0.008). The most frequent adverse events were upper lid ptosis, diplopia, ecchymosis, and localized bruising. Conclusions This long-term multicentre study supports a high efficacy and good safety profile of BoNT-A for treatment of BEB, HFS, and EN. The BEI indexes indicate a significantly greater BoNT-A-dose escalation for BEB patients compared with HFS or EN patients and a significantly greater BEI-% in younger vs older BEB patients. These results confirm a greater efficacy in the elderly and provide a framework for long-term studies with a more flexible and reliable evaluation of drug-dose escalation.

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

“…These findings corroborate those published studies. 16,17,18,19,20,21,22,23,24 . The success rate in the present study was 94.73% when injections that did not produce any effect or produced a short-term or minor effect were excluded.…”

Effect of previous botulinum neurotoxin treatment on microvascular decompression for hemifacial spasm

“…Botulinum neurotoxin, although a less invasive treatment than surgery, can result in potentially life-threatening allergic reactions and systemic manifestation of toxin adverse effects. 3,7 Because HFS is a disabling condition, the choice to receive repeated noninvasive local injections of botulinum neurotoxin appears to be more acceptable before MVD surgery is considered. In the present study, we analyzed and compared 2 patients groups, one that underwent botulinum neurotoxin treatment prior to MVD, and another that did not.…”

Practice guideline update summary: Botulinum neurotoxin for the treatment of blepharospasm, cervical dystonia, adult spasticity, and headache

“…Benefit from aboBoNT-A or onaBoNT-A was sustained for at least 15 years in 128 patients, 11 onaBoNT-A for 10 years in 83 patients, 12 and incoBoNT-A for 69 weeks in 82 patients. 13 In 288 patients arbitrarily assigned to toxin formulation, similar degrees of benefit were sustained for at least 10 years (onaBoNT-A), 15 years (aboBoNT-A), and 5 years (incoBoNT-A).…”