Alternating Unilateral Versus Bilateral Injections of Botulinum Toxin for the Treatment of Adductor Spasmodic Dysphonia

Objective This study aimed to compare the long-term efficacy, durability, and dose and interval stability between alternating unilateral and bilateral injections of botulinum neurotoxin type A for the treatment of adductor spasmodic dysphonia. Study Design Retrospective cohort study. Setting Academic tertiary medical center. Methods A total of 137 patients (105 alternating unilateral and 32 bilateral injections) who were administered ≥5 injections of botulinum neurotoxin type A were included in this study. The mean dosage change, dose adjustment ratio (number of dose increases/total number of injections), and stability of treatment responses were compared between the alternating unilateral and bilateral injection groups. Results Long-term changes in the mean dosages for alternating unilateral (mean ± SD, –0.010 ± 0.048 IU) and bilateral (–0.042 ± 0.142 IU) injections did not differ between groups ( P = .225), suggesting that both methods follow a decreasing dosing trend over time. The dose adjustment ratio also did not differ between groups ( P = .077), although a longer average treatment interval ( P < .001) and duration of hoarse voice ( P = .045) were found in the bilateral injection group. The proportion of stable patients who did not increase injection dose and had regular follow-up did not differ between the groups. Conclusion Both alternating unilateral and bilateral injection methods showed a long-term decreasing dosing trend, with comparable levels of efficacy, durability, and stability for treating adductor spasmodic dysphonia. Our findings indicate that alternating unilateral injections can be routinely performed with fewer side effects, albeit at shorter treatment intervals, than bilateral injections.

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A Review of Tolerance and Safety Profiles of Long-Term Botulinum Neurotoxin Type A in Asian Patients with Hemifacial Spasm and Benign Essential Blepharospasm

Neuro-Ophthalmology ◽

10.1080/01658107.2021.1916043 ◽

2021 ◽

pp. 1-8

Author(s):

Kenneth K. A. Hei Lai ◽

Alan Tsang ◽

Andrew K. T. Kuk ◽

Callie K. L. Ko ◽

Edwin Chan ◽

...

Keyword(s):

Hemifacial Spasm ◽

Botulinum Neurotoxin ◽

Type A ◽

Botulinum Neurotoxin Type A ◽

Asian Patients ◽

Essential Blepharospasm

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Patient perspectives on the therapeutic profile of botulinum neurotoxin type A in cervical dystonia

Journal of Neurology ◽

10.1007/s00415-020-10217-7 ◽

2020 ◽

Author(s):

Cynthia Comella ◽

Joaquim J. Ferreira ◽

Emilie Pain ◽

Marion Azoulai ◽

Savary Om

Keyword(s):

Quality Of Life ◽

Cervical Dystonia ◽

Botulinum Neurotoxin ◽

Type A ◽

Peak Effect ◽

Botulinum Neurotoxin Type A ◽

The Mean ◽

The Impact ◽

Therapeutic Profile

Abstract Background Botulinum neurotoxin type A (BoNT-A) is an effective pharmacological treatment for the management of cervical dystonia (CD) that requires repeated administration at variable intervals. We explored patient perceptions of the impact of CD and the waning of BoNT-A therapeutic effects. Methods An internet-based survey was conducted through Carenity, a global online patient community, from May to September 2019. Eligible respondents were adults with CD who had ≥ 2 previous BoNT-A injections. Results 209 respondents (81% females; mean age of 49.7 years) met the screening criteria. The mean BoNT-A injection frequency was 3.9 injections/year. The mean reported onset of BoNT-A therapeutic effect was 11.7 days and the time to peak effect was 4.5 weeks. Symptom re-emergence between injections was common (88%); the time from injection to symptom re-emergence was 73.6 days (~ 10.5 weeks). Treatment was not reported to completely abolish symptoms, even at peak effect. However, symptom severity was rated (0 = no symptoms; 10 = very strong symptoms) as lowest at the peak of treatment effects (mean scores ~ 3/10), increasing as the effects of treatment start waning (~ 5.5/10) and was strongest one day before the next session (~ 7–8/10). The impact of CD on quality of life followed the same ‘rollercoaster’ pattern. Conclusions This survey highlights the burden of CD symptoms, even in patients undergoing regular treatment. Symptom re-emergence is common and has significant impact on daily activities and quality of life. Greater awareness of the therapeutic profile of BoNT-A treatment should lead to better informed therapeutic discussions and planning.

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Jitter Evaluation in Distant and Adjacent Muscles after Botulinum Neurotoxin Type A Injection in 78 Cases

Toxins ◽

10.3390/toxins12090549 ◽

2020 ◽

Vol 12 (9) ◽

pp. 549

Author(s):

Joao Aris Kouyoumdjian ◽

Carla Renata Graça ◽

Fabio Nazare Oliveira

Keyword(s):

Movement Disorders ◽

Calcium Channel Blockers ◽

Botulinum Neurotoxin ◽

Beta Blockers ◽

Type A ◽

Voluntary Activation ◽

Channel Blockers ◽

Botulinum Neurotoxin Type A ◽

Local Spread ◽

The Mean

To study the jitter parameters in the distant (DM) and the adjacent muscle (AM) after botulinum neurotoxin type A (BoNT/A) injection in 78 patients, jitter was measured by voluntary activation in DM (n = 43), and in AM (n = 35). Patients were receiving BoNT/A injections as a treatment for movement disorders. Mean age 65.1 years (DM) and 61.9 years (AM). The mean jitter was abnormal in 13.9% (maximum 41.4 µs) of DM, and 40% (maximum 43.7 µs) of AM. Impulse blocking was sparse. We found no correlation of the mean jitter to age, BoNT/A most recent injection (days/units), number of muscles injected, total BoNT/A units summated, number of total BoNT/A sessions, beta-blockers/calcium channel blockers use, and cases with local spread symptoms such as eyelid drop/difficulty swallowing. Maximum mean jitter (41.4/43.7 µs) for DM/AM occurred 61 and 131 days since the most recent BoNT/A, respectively. The far abnormal mean jitter (32.6/36.9 µs) occurred 229 and 313 days since the most recent BoNT/A. We suggested that jitter measurement can be done after BoNT/A in a given muscle other than the injected one, after 8 (DM) and 11 (AM) months, with reference >33 µs and >37 µs, respectively.

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