Outcome predictors, efficacy and safety of Botox and Dysport in the long-term treatment of hemifacial spasm

Real-world differences in dosing and clinical utilization of OnabotulinumtoxinA and AbobotulinumtoxinA in the treatment of upper limb spasticity

According to prescribing information, potency units are not interchangeable between botulinum toxin A products. This exploratory study compared real-world dosing and utilization of onabotulinumtoxinA and abobotulinumtoxinA in adults with upper limb spasticity. In this retrospective study, 101 clinicians provided chart data via online surveys for 215 US post-stroke patients treated for upper limb spasticity with ≥3 onabotulinumtoxinA or abobotulinumtoxinA doses (phase 1: 9/18/2020-12/10/2020; phase 2: 9/30/2021-12/7/2021). Most participating clinicians were physicians (70.3%) specializing in neurology (71.3%) or physiatry (20.8%). In the onabotulinumtoxinA (n = 107) and abobotulinumtoxinA (n = 108) groups, ∼75% of patients had moderate-to-severe spasticity. A range of onabotulinumtoxinA:abobotulinumtoxinA dose ratios (1:2.2 [95%CI: 1.8-2.6] to 1:4.1 [95%CI: 3.0-6.0]) was observed across muscles. For the most recent dose, mean number of muscles injected was greater for onabotulinumtoxinA (4.3) versus abobotulinumtoxinA (3.1; P = 0.0003). For onabotulinumtoxinA versus abobotulinumtoxinA, the proportion of injections was 81.3% versus 63.9% (P = 0.0067) in forearm muscles and 23.4% versus 3.7% (P = 0.0001) in hand muscles. Mean injection intervals were similar (onabotulinumtoxinA: 102.0 days; abobotulinumtoxinA: 99.1 days). Differences in real-world dosing and utilization of onabotulinumtoxinA and abobotulinumtoxinA for upper limb spasticity were observed. There was no standard dose-conversion ratio, consistent with each product's prescribing information.

Clinical Application of Botulinum Toxin for Hemifacial Spasm

Hemifacial spasm is typically caused by contact between the facial nerve and blood vessels. Microvascular decompression, a treatment that directly addresses this pathogenesis, is often considered the most effective treatment method. However, surgery is not immediately performed for patients at risk from the surgical treatment, or for those with an unclear diagnosis. In these instances, Botulinum toxin injection can help manage the patient's symptoms. Numerous studies corroborate the effectiveness and safety of Botulinum toxin treatment, with large-scale studies indicating symptom control lasts, on average, around 15 weeks.

Efficacy and safety of long-term botulinum toxin treatment for acquired cervical dystonia: a 25-year follow-up

Botulinum toxin A (BoNT/A) is the first-line treatment for idiopathic cervical dystonia (ICD) and is widely used in the clinical setting. To date, scanty data are available on the effectiveness of BoNT in treating acquired cervical dystonia (ACD). Here we present a long-term follow-up of ACD patients treated with BoNT/A that focused on safety and efficacy. The study included subjects who had received at least six treatments of three commercially available BoNT/A drugs [abobotulinumtoxinA (A/Abo), incobotulinumtoxinA (A/Inco) and onabotulinumtoxinA (A/Ona)]. Safety and efficacy were assessed based on patients' self-reports regarding adverse effects (AE), duration of improvement of dystonia and/or pain relief. Global clinical improvement was measured on a six-point scale. 23 patients with ACD were administered 739 treatments (A/Abo in 235, A/Inco in 72, A/Ona in 432) with a mean number of treatments of 31 ± 20 (range 6-76) and duration of 10 ± 6 weeks (range 2-25). The mean dose was 737 ± 292 U for A/Abo, 138 ± 108 U for A/Inco and 158 ± 80 U for A/Ona. The average benefit duration was 89 ± 26 (A/Abo), 88 ± 30 days (A/Inco), and 99 ± 55 days (A/Ona) (p = 0.011); global clinical improvement for all sessions was 4 ± 1. ANOVA one-way analysis indicated that A/Ona had the best profile in terms of duration (p < 0.05), whereas A/Abo had the best pain relief effect (p = 0.002). Side effects were reported in 9% of treatments (67/739), with ten treatments (1%) complicated by two side effects. Most side effects were rated mild to moderate; severe side effects occurred following three treatments with the three different BoNT; two required medical intervention. No allergic reactions were reported. Even after 25 years of repeated treatments, all serotypes of BoNT demonstrate positive effects in treating ACD with long-lasting efficacy and safety.

Therapeutic Approach to Botulinum Injections for Hemifacial Spasm, Synkinesis and Blepharospasm

The aim of this study was to show our therapeutic outcome of botulinum injection to the facial muscles and thereby to find the best therapeutic concept which should be embraced. The decision to treat the lower eyelid with 1-point or 2-points injection was randomly taken as there is no consensus regarding this debate. Injections of the lateral end of the upper eyelid were performed more laterally to the conventional injection point, just lateral to the conjunction of the upper and lower eyelids. Twenty-three patients (12 hemifacial spasm, 6 blepharospasm, 5 post facial palsy synkinesis) were enrolled. Data were retrieved from 112 visits between 2019 and 2022. Overall, 84.9% of the treatments had moderate or marked improvement. The most common side effect was facial weakness (11.8%). Neither ptosis nor diplopia were noted. Two-points regimen in the lower eyelid was associated with a lower risk of facial weakness (p = 0.01), compared to 1-point regimen, with a better therapeutic outcome as reflected by more favorable PGI-C scores (p = 0.04). Injection of the pretarsal segment of the upper eyelid, just onto or even lateral to the conjunction of the upper and lower eyelids, lowers the risk of ptosis.

Time to onset and duration of botulinum toxin efficacy in movement disorders

Background

Botulinum toxin (BoNT) is a valuable treatment in movement disorders; however, time to onset and duration of efficacy may widely differ among patients. We aimed to clarify the impact of main demographic and clinical features on time to onset and duration of BoNT efficacy.

Methods

We analyzed time-to-onset and duration of BoNT efficacy in 186 consecutive patients treated with BoNT for blepharospasm, cervical dystonia, facial hemispasm, oromandibular dystonia, limb dystonia, and sialorrhea due to Parkinsonism. The following factors were considered as potential efficacy predictors: doses and types of toxin, sex, age, years of treatment, and clinical condition. Kruskall–Wallis, Spearman correlation, and multivariate linear regression were used for statistical analysis.

Results

The average time to onset was 6.7 ± 5 days and duration of BONT efficacy 78.5 ± 28.4 days. Both time to onset and duration of efficacy were correlated with BoNT doses (p: 0.007 and p: 0.02). The multiple regression analysis showed that sex, age, years of BoNT treatment, doses, type of toxin, and clinical condition significantly predicted time to onset (F(11, 171) = 2.146, p: 0.020) with age being the strongest predictor (p: 0.004).

The same model explained 20.1% of the variance of duration of BoNT efficacy, showing a significant prediction of the outcome (F(11, 164) = 3.754, p < 0.001), with doses (p < 0.001), type of toxin (p: 0.017), and clinical condition (p < 0.001) being the strongest predictors.

Conclusion

Our findings suggest that age, type of toxin, clinical condition and especially doses may account for the variability of BoNT efficacy in terms of time to onset and duration.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-10995-2.

Botulinum Toxin for the Treatment of Hemifacial Spasm: An Update on Clinical Studies

Hemifacial spasm (HFS) is a movement disorder characterized by involuntary contractions of the facial muscles innervated by the seventh cranial nerve. Generally, it is associated with a poor quality of life due to social embarrassment and can lead to functional blindness. Moreover, it is a chronic condition, and spontaneous recovery is rare. Intramuscular injections of Botulinum Toxin (BoNT) are routinely used as HFS treatment.

METHODS

We reviewed published articles between 1991 and 2021 regarding the effectiveness and safety of BoNT in HFS as well as any reported differences among BoNT formulations.

RESULTS

The efficacy of BoNT for HFS treatment ranged from 73% to 98.4%. The mean duration of the effect was around 12 weeks. Effectiveness did not decrease over time. Adverse effects were usually mild and transient. The efficacy and tolerability of the different preparations appeared to be similar. Among the studies, dosage, injected muscles, intervals of treatment, and rating scales were variable, thus leading to challenges in comparing the results.

CONCLUSIONS

BoNT was the treatment of choice for HFS due to its efficacy and safety profile. Further studies are needed to investigate the factors that influence the outcome, including the optimal timing of treatment, injection techniques, dosage, and the best selection criteria for formulations.

Dry Eye Disease in Hemifacial Spasm Patients Treated with Botulinum Toxin Type A

Purpose

To assess the impact of botulinum toxin type A (BTX-A) on signs and symptoms of dry eye (DE) in affected eye of hemifacial spasm (HFS) patients and to compare the prevalence of DE between affected and non-affected eye in HFS patients.

Patients and Methods

This prospective study included participants with unilateral HFS, who received BTX-A injection as a treatment. The eyes ipsilateral to the spasm side were used as studied eyes and the contralateral eyes were used as controls. The Ocular Surface Disease Index (OSDI) score, tear break-up time (TBUT), corneal fluorescein staining, and Schirmer I test were measured at baseline, 1 and 3 months after BTX-A injection. Fluorescein clearance test (FCT) was evaluated at baseline and at 1 month after BTX-A injection.

Results

Thirty-one participants (6 males and 25 females; mean age 61±10 years) were included. The prevalence of DE according to the Asia Dry Eye Society was not significantly different between affected (37.93%) and non-affected eyes (27.6%); P=0.083. At baseline, there was no significant difference in TBUT, Schirmer test, basal tear secretion, presence of delayed tear clearance, and presence of reflex tear secretion between affected and non-affected eyes, while significant difference in Oxford scheme grade was observed (P=0.031). OSDI score, TBUT, Oxford scheme grade, and Schirmer test at 1 month (P=0.817, 0.796, 0.534, 0.556), and 3 months (P=0.803, 0.904, 0.936, 0.684) after BTX-A injection did not significantly change from baseline in affected eyes. FCT results were not significantly different between baseline and at 1-month follow-up in both groups. All findings were corresponding in both naïve and long-term botulinum toxin injection groups.

Conclusion

We found no significant effect of BTX-A on signs and symptoms of DE in patients with HFS. Moreover, there was no significant association between HFS and DE. However, we found significant corneal surface damage in the affected eyes, which emphasized importance of ocular surface evaluation and prompt treatment in HFS patients.

Real-world experience with botulinum toxin A for the treatment of hemifacial spasm: A study of 1138 injections

BACKGROUND

Hemifacial spasm (HFS) is a chronic, potentially disabling disorder that often requires long-term management with botulinum toxin (BoNT). In a country where healthcare costs limit compliance to medical follow-up and treatment, the study aims to provide a real-world experience on the use of BoNT for HFS among Filipinos.

METHODS

We retrospectively collected data from 162 HFS patients who received 1138 botulinum toxin (BoNT) injections from 2006 to 2019 in our movement disorders center in the Philippines. We described their clinical profile and treatment response.

RESULTS

The mean age at onset of disease was 47.7 ± 10.72 years. Majority of the patients reported a baseline moderate disease severity and disease frequency of >75% of waking time (59.8% and 46.9%, respectively). Most patients (61.73%) received 5 or less injections during the follow-up period. The mean duration of follow-up was 2.96 ± 4.28 years. The overall duration of treatment effect per injection was 3.6 ± 1.3 months while the mean interval between injections was 6 ± 5 months. There was no difference in the symptom improvement and duration between onabotulinumtoxinA and abobotulinumtoxinA. Side effects were infrequent.

CONCLUSION

This study supports existing evidence on the efficacy and safety of BoNT for the symptomatic relief of HFS. In the Philippines, long-term treatment with BoNT may be limited by the cost of the procedure as majority of our patients had a few injections with long treatment intervals.

Hemifacial spasm through the last three decades: From etiology to efficacy and safety of long-term botulinum toxin treatment

BACKGROUND

Hemifacial spasm (HFS) is an uncommon movement disorder characterized by involuntary contractions of muscles innervated by the facial nerve. The aim of this study is to analyze the etiology of HFS as well as the efficacy and safety of long-term botulinum toxin type A (BTX-A) treatment.

METHODS

Retrospective study including 125 patients with HFS treated with BTX-A from 1993 to 2019. Demographic and etiological variables as well as doses, number of sessions of BTX-A, infiltrated muscles, therapeutic response according to Patient Global Impression of Change Scale (PGIC-S), side effects and adjuvant treatments were analyzed. In addition, these variables were compared according to the etiology (idiopathic versus secondary).

RESULTS

92 patients (73.6%) were women and the mean age at diagnosis was 58.63 years (SD 15.4). The etiology was idiopathic in 79 patients (63.2%), 17.6% were secondary to Bell's palsy, 14.4% to vascular compression and 2.4% to tumors. A higher total dose per session was observed in the secondary group. PGIC-S showed a good response in 96% of cases. 16 patients (12.8%) required pharmacological concomitant treatment. 59 patients (47.2%) developed side effects. Transient eyelid ptosis and facial weakness were the most common.

CONCLUSIONS

The structural origin of a significant number of cases of HFS makes essential to complete an etiological diagnosis in all patients. In addition, the existence of a secondary cause could be associated with greater doses of BTX-A to achieve a good response. Regardless the etiology, long-term treatment with BTX-A in HFS is safe and effective.

Experiences on The Administration of Botulinum Toxin in Movement Disorders

Background and objectives

Botulinum toxin injection has been used for many years for various indications such as cervical dystonia, blepharospasm, oromandibular dystonia, hemifacial spasm in neurology. Botulinum toxin injections have been made in our clinic for about ten years. We want to report our experiences about botulinum toxin treatment in neurologic disease.

Methods

In this study, the data of the patients receiving BoNT injection between January 2018 and December 2019 was retrospectively analyzed. Age, gender, botulinum toxin indications, and mean dose, duration of efficacy, side effects noted for each injection were recorded.

Results

There were 122 patients who received botulinum toxin injections between January 2018 and December 2019. Of the 122 patients identified, 28 had cervical dystonia, 61 had HFS, 21 had blepharospasm, 4 had generalized dystonia, 1 had hemidystonia following thalamic bleeding, 1 had tardive dystonia, 4 had migraine, 1 had bruxism and 1 had both migraine and bruxism.

Conclusion

BoNT injection is a treatment that has been used for various indications in neurology for almost 40 years. Side effects are limited and temporary with appropriate injections. We also had a wide range of indication profiles and high numbers of patients to whom we administered the BoNT treatment.

Efficacy and Complications of Microsurgical Neurovascular Decompression in 55 Patients With Hemifacial Spasm

OBJECTIVE

To analyze the efficacy and complications of microvascular decompression for hemifacial spasm.

STUDY DESIGN

Retrospective study.

SETTING

Regional hospital.

METHODS

Fifty-five patients with hemifacial spasm were treated by microvascular decompression. All patients with hemifacial spasm who underwent retrosigmoid microvascular decompression from May 2004 to January 2017 were included. Patients with no conflict on preoperative magnetic resonance imaging or with an alternate diagnosis were excluded.

RESULTS

The overall cure rate was 83.64%, with an average follow-up of 7.4 years. A left-sided hemifacial spasm was a healing-promoting factor (P = .01). The median healing was 0.03 months, and the mean was 6 months. The efficacy remained high in the medium term (88% at 3 years), long term (90.24% at 5 years), and very long term (90.48% at 8 years). The recurrence rate was 9.8%. Favorable criteria included a right-sided spasm (P = .01) and an average age of 62 years (P = .03). The specific complications were permanent facial palsy (3.63%), unilateral deafness (5.45%), and hearing loss (3.63%). No death was reported. Regarding the quality of life of the patients, 94.7% had a modified HFS-8 postoperative score of 0 (Hemifacial Spasm 8 Quality of Life Scale).

CONCLUSION

Microvascular decompression for hemifacial spasm is an effective and lasting technique. Its low rate of complications and the considerable quality-of-life improvement should lead surgeons to propose it to patients as soon as botulinum toxin injections become ineffective or poorly tolerated.

Botulinum Toxin Type A Overdoses: Analysis of the FDA Adverse Event Reporting System Database

INTRODUCTION

Published literature on overdoses related to botulinum toxin A (BtxA) agents is scarce.

OBJECTIVE

The aim of this study was to assess the BtxA drug class' respective agents for associations with overdose.

METHODS

United States Food and Drug Administration (FDA) adverse event reporting system (FAERS) database was utilized to search for overdoses. The analysis was conducted on data between second quarter 2014 and third quarter 2017. BtxA cases were included when they were considered the "Primary Suspect" drug. Overdose was defined as presence of 'overdose' being reported as an adverse event. Primary outcome was incidence of 'overdose' compared within the respective agents. Additionally, a disproportionality analysis was conducted utilizing reporting odds ratio (ROR) versus onabotulinumtoxinA as a referent while controlling for confounding variables.

RESULTS

A total of 3,837,406 unique adverse events were reported during the study period for all drugs in the FAERS database. Of which, 13,078 were BtxA cases. The rate of adverse events involving overdose for abobotulinumtoxinA (20.2%; 215/1065) was significantly higher than both onabotulinumtoxinA (0.4%; 48/11,323; p < 0.0001) and incobotulinumtoxinA (0.1%; 1/690; p < 0.0001). In the regression analysis, abobotulinumtoxinA (ROR 73.26; 95% CI 51.17-104.90) had a significant association with overdose, whereas incobotulinumtoxinA (ROR 0.73; 95% CI 0.10-5.36) did not, versus the referent onabotulinumtoxinA.

CONCLUSION

The present analysis showed adverse events of abobotulinumtoxinA were significantly associated with overdose versus the other two BtxA agents. Overdose can be difficult to research, particularly for in-clinic administered drugs. Future studies should venture to confirm these results in new and novel ways.

Effect of Hemifacial Spasm on Intraocular Pressure Measurement

Purpose

To evaluate the effect of hemifacial spasm (HFS) on intraocular pressure (IOP) measurement.

Methods

Twenty-four consecutive patients with HFS and 25 age- and gender-matched randomly selected eyes of healthy volunteers underwent corneal pachymetry and IOP measurements using Goldmann applanation tonometer (GAT) and noncontact tonometer (NCT). IOP measurements were performed before (during HFS) and 2 weeks after Botox injections in HFS patients and in healthy volunteers without Botox injections.

Results

There was no statistical difference between involved eye side and uninvolved eye side of HFS patients in measured central corneal thickness. Similarly, no difference was found between involved eye side of HFS patients and controls. There were no statistically significant differences comparing IOP values before treatment and levels measured at 2 weeks of Botox injections, either with GAT (p = 0.33, 0.11) or NCT (p = 0.80, 0.43) devices in the involved eyes and uninvolved eyes of patients with HFS, respectively. There were also no significant differences in these parameters (GAT (p = 0.63) and NCT (p = 0.54)) in controls.

Conclusions

Contractions in facial muscles may not lead to significant increase in IOP in HFS patients. This result may help clinical decision making in the treatment of glaucoma patients with HFS. This trial is registered with NCT03390803.

Botulinum Neurotoxins: Biology, Pharmacology, and Toxicology

The study of botulinum neurotoxins (BoNT) is rapidly progressing in many aspects. Novel BoNTs are being discovered owing to next generation sequencing, but their biologic and pharmacological properties remain largely unknown. The molecular structure of the large protein complexes that the toxin forms with accessory proteins, which are included in some BoNT type A1 and B1 pharmacological preparations, have been determined. By far the largest effort has been dedicated to the testing and validation of BoNTs as therapeutic agents in an ever increasing number of applications, including pain therapy. BoNT type A1 has been also exploited in a variety of cosmetic treatments, alone or in combination with other agents, and this specific market has reached the size of the one dedicated to the treatment of medical syndromes. The pharmacological properties and mode of action of BoNTs have shed light on general principles of neuronal transport and protein-protein interactions and are stimulating basic science studies. Moreover, the wide array of BoNTs discovered and to be discovered and the production of recombinant BoNTs endowed with specific properties suggest novel uses in therapeutics with increasing disease/symptom specifity. These recent developments are reviewed here to provide an updated picture of the biologic mechanism of action of BoNTs, of their increasing use in pharmacology and in cosmetics, and of their toxicology.

Use of Botulinum Neurotoxin in Ophthalmology

Botulinum neurotoxin (BoNT) is the first biological toxin used in the treatment of ophthalmic diseases and to decrease skin wrinkles as an aesthetic agent. When used appropriately, it weakens the force of muscular contraction and/or inhibits glandular secretion. The most common areas for botulinum toxin treatment are the upper face, including the glabella, forehead, brows, and lateral canthal lines, or crow's feet. By relaxing the muscles causing wrinkles, non-permanent results may be achieved with its use. BoNT has gained widespread use in a variety of ophthalmic diseases. The effect of BoNT is temporary, but the therapeutic benefit is usually maintained even after repeated injections. Treatment is usually well tolerated. Complications and side effects associated with the treatment are rare and temporary. Complications occur due to weakness (chemodenervation) of adjacent muscle groups, immunological mechanisms and injection technique. Current therapeutic indications, doses, complications and contraindications of BoNT use in the following disorders related to ophthalmology were investigated: aesthetic use, strabismus, blepharospasm, hemifacial spasm, eyelid retraction, entropion, lacrimal hypersecretion syndrome, and facial paralysis.

Increasing the area and varying the dosage of Botulinum toxin a injections for effective treatment of hemifacial spasm

CONCLUSION

Wider-area botulinum toxin (BT) injection with the dosage depending on specific pathology is a promising approach for the treatment of hemifacial spasm (HFS), resulting in effective and long-lasting control of HFS with fewer side-effects.

OBJECTIVE

The aim of this study was to develop a BT injection strategy that minimizes complications by considering the causes, duration, and electrophysiologic features of the disease, as well as the patient's age.

METHODS

From July 2011 to July 2015, 26 patients were included in the strategy. The mean age was 61.8 ± 14.6. In the case of essential HFS, 2 units/injection site was the standard dosage. If a patient was aged over 60 and had a reduced electromyogram (EMG) amplitude, the dosage was reduced by 0.5 units/site. In the case of post-paralytic and tumor-induced HFS, 1.5 units/site was the standard dosage. All cases were managed by alternating injections of Botox and Dysport with no physical therapy.

RESULTS

Most HFS patients treated with the injection strategy had complete remission of HFS within 1 week. The average number of BT injection sites was 22.6 ± 6.7. The mean total BT dosage on the affected side was 28.6 ± 4.9 units. The mean duration of BT efficacy was 28.6 ± 7.7 weeks.

Clinical differences between botulinum neurotoxin type A and B

In humans, the therapeutic use of botulinum neurotoxin A (BoNT/A) is well recognized and continuously expanding. Four BoNTs are widely available for clinical practice: three are serotype A and one is serotype B: onabotulinumtoxinA (A/Ona), abobotulinumtoxinA (A/Abo) and incobotulinumtoxinA (A/Inco), rimabotulinumtoxinB (B/Rima). A/Abo, A/Inco, A/Ona and B/Rima are all licensed worldwide for cervical dystonia. In addition, the three BoNT/A products are approved for blepharospasm and focal dystonias, spasticity, hemifacial spasm, hyperhidrosis and facial lines, with remarkable regional differences. These toxin brands differ for specific activity, packaging, constituents, excipient, and storage. Comparative literature assessing the relative safety and efficacy of different BoNT products is limited, most data come from reports on small samples, and only a few studies meet criteria of evidence-based medicine. One study compared the effects of BoNT/A and BoNT/B on muscle activity of healthy volunteers, showing similar neurophysiological effects with a dose ratio of 1:100. In cervical dystonia, when comparing the effects of BoNT/A and BoNT/B, results are more variable, some studies reporting roughly similar peak effect and overall duration (at a ratio of 1:66, others reporting substantially shorter duration of BoNT/B than BoNT/A (at a ratio 1/24). Although the results of clinical studies are difficult to compare for methodological differences (dose ratio, study design, outcome measures), it is widely accepted that: BoNT/B is clinically effective using appropriate doses as BoNT/A (1:40-50), injections are generally more painful, in most of the studies on muscular conditions, efficacy is shorter, and immunogenicity higher. Since the earliest clinical trials, it has been reported that autonomic side effects are more frequent after BoNT/B injections, and this observation encouraged the use of BoNT/B for sialorrhea, hyperhidrosis and other non-motor symptoms. In these indications the efficacy of toxins A and B are comparable and dose ratio is 1:25-30.

Botulinum toxin injections for the treatment of hemifacial spasm over 16 years

The aim of this study was to investigate the efficacy and side effects of botulinum toxin (BTX) in the treatment of hemifacial spasm (HFS). We also focused on the divergence between different injection techniques and commercial forms. We retrospectively evaluated 470 sessions of BTX injections administered to 68 patients with HFS. The initial time of improvement, duration and degree of improvement, and frequency and duration of adverse effects were analysed. Pretarsal and preseptal injections and Botox (Allergan, Irvine, CA, USA) and Dysport (Ipsen Biopharmaceuticals, Paris, France) brands were compared in terms of efficacy and side effects, accompanied by a review of papers which reported BTX treatment of HFS. An average of 34.5 units was used per patient. The first improvement was felt after 8 days and lasted for 14.8 weeks. Patients experienced a 73.7% improvement. In 79.7% of injections, no adverse effect was reported, in 4.9% erythema, ecchymosis, and swelling in the injection area, in 3.6% facial asymmetry, in 3.4% ptosis, in 3.2% diplopia, and in 2.3% difficulty of eye closure was detected. Patients reported 75% improvement on average after 314 sessions of pretarsal injections and 72.7% improvement after 156 sessions of preseptal injections (p=0.001). The efficacy and side effects of Botox and Dysport were similar. BTX is an effective and safe treatment option for HFS. No difference was determined between Botox and Dysport, and pretarsal injection is better than preseptal injection regarding the reported degree of improvement.

Conservative treatment of neuromuscular scoliosis in adult tetraplegia: a case report

We report successful correction of new onset neuromuscular scoliosis without spinal surgery in a man who is 30-years post-American Spinal Injury Association Impairment Scale grade A C6 injury with new onset of left neuromuscular scoliosis (Cobb angle 45°) after a motor vehicle collision. Interventions included nightly low-load prolonged stretching (LLPS) (4h left side lying over bolster), a series of 6 botulinum toxin injections (BTIs) at 3-month intervals, and progressive seating adjustments to counteract the spinal curvature. Monthly seating adjustments included rear quadrant wedging, lateral supports, and hip blocking to promote erect and symmetrical posture. A normative Cobb angle (5°) was achieved after 8 months of treatment. Improvements in alignment were demonstrated in physical examination outcome measures at the final session and follow-up. LLPS, seating adjustments, and paraspinal BTI are nonsurgical options for treating neuromuscular scoliosis in adults with tetraplegia. Further studies are necessary to determine optimum protocols and examine generalizability of these treatment methods.

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

Object

The objective of this study was to investigate the clinical characteristics, intraoperative findings, complications, and outcomes after the first microvascular decompression (MVD) in patients with and without previous botulinum neurotoxin treatment for hemifacial spasm (HFS).

Methods

The authors analyzed 246 MVDs performed at the University of Pittsburgh Medical Center between January 1, 2000, and December 31, 2007. One hundred and seventy-six patients with HFS underwent botulinum neurotoxin injection treatment prior to first MVD (Group I), and 70 patients underwent their first MVD without previous botulinum neurotoxin treatment (Group II). Clinical outcome data were obtained immediately after the operation, at discharge, and at follow-up. Follow-up data were collected from 177 patients with a minimum follow-up period of 9 months (mean 54.48 ± 27.84 months).

Results

In 246 patients, 89.4% experienced immediate postoperative relief of spasm, 91.1% experienced relief at discharge, and 92.7% experienced relief at follow-up. There was no significant difference in outcomes and complications between Group I and Group II (p > 0.05). Preoperatively, patients in Group I had higher rates of facial weakness, tinnitus, tonus, and platysmal involvement as compared with Group II (p < 0.05). The posterior inferior cerebellar artery and vertebral artery were intraoperatively identified as the offending vessels in cases of vasculature compression in a significantly greater number of patients in Group II compared with Group I (p = 0.008 and p = 0.005, respectively, for each vessel). The lateral spread response (LSR) disappeared in 60.48% of the patients in Group I as compared with 74.19% in Group II (p > 0.05). No significant differences in complications were noted between the 2 groups.

Conclusions

Microvascular decompression is an effective and safe procedure for patients with HFS previously treated using botulinum neurotoxin. Intraoperative monitoring with LSR is an effective tool for evaluating adequate decompression.

Botulinum toxin in hemifacial spasm: the challenge to assess the effect of treatment

Hemifacial spasm is characterized by intermittent tonic or clonic contractions of the muscles supplied by the facial nerve. Although vision is less impaired than in patients with blepharospasm, the disease can impose significant psychosocial burden on patient's life. Botulinum toxin (BoNT) is the well-established pharmacotherapy of choice, but evidence from controlled clinical trials is sparse. There is a broad variety of rating scales used in clinical studies with BoNT and obviously no consensus has been reached how to assess treatment outcome in hemifacial spasm. Clinical rating scales focusing on objective function were used in a couple of controlled studies with BoNT and were appropriate to discriminate between BoNTA and placebo. But it has not been shown that they would be sensitive enough to detect minor differences between several BoNT formulations. Although most of the clinical scales consist of a five-point rating, the descriptors for the ordinal numbers are not necessarily the same so that the results of different clinical studies are not comparable to each other. The main disadvantage of clinical scales is that they do not take into account patient's perspective of disability and impact on daily life. For this reason some clinical studies applied health-related quality of life (HRQoL) questionnaires to assess efficacy, and one research group worked on the development of disease-specific tools. Although these HRQoL questionnaires have been validated and a good correlation to disease severity could be demonstrated, they are far from having become an established variable for efficacy assessment in hemifacial spasm trials. The challenge remains to establish tools which are appropriate to rate BoNT treatment effects in hemifacial spasm. Currently, it is virtually impossible to identify one rating scale which can cover all relevant aspects of the disorder. In consequence we recommend the implementation of a combination of different rating scales which address functional impairment as well as those issues which are most important to patients. Further research is needed to standardize and validate rating scales for hemifacial spasm in clinical studies.

Is it always necessary to apply botulinum toxin into the lower facial muscles in hemifacial spasm?: a randomized, single-blind, crossover trial

BACKGROUND

Botulinum toxin (BTX) injections are accepted as safe and efficacious in the treatment of hemifacial spasm (HFS), but it is still debated whether BTX treatment of lower facial muscles should be performed or not.

OBJECTIVE

The study aims to evaluate the necessity of BTX administration into lower facial muscles in patients with HFS.

METHODS

A randomized, single-blind, crossover, clinical trial was conducted. Twenty-three HFS patients were randomly allocated to two different application methods. The patients were administered BTX type A into both the orbicularis oculi and perioral muscles in the first method and BTX type A into the orbicularis oculi but placebo into the perioral muscles in the second method. Subjects were crossed over to the alternate method when they needed BTX injection with a minimum of 3 months' duration. All the patients underwent both methods with no change in the total dose of BTX.

RESULTS

All the patients benefited from BTX treatment regardless of the methods. However, in the patients with severe lower facial muscle involvement, the application of BTX into both orbicularis oculi and lower facial muscles led to better results.

CONCLUSION

Our data suggest that BTX application to lower facial muscles might not be necessary in patients with mild lower facial involvement.

Hemifacial spasm and reinnervation synkinesias: long-term treatment with either Botox or Dysport

Botulinum toxin is considered the treatment of choice for hemifacial spasm (HFS) and reinnervation synkinesias (RS). We present 133 patients with HFS (n = 97) and RS (n = 36) who have been treated with either Botox (n = 78) or Dysport (n = 55) exclusively for 6 years (range 2-12 years). The Botox dose was 21 +/- 8 MU, the Dysport dose 46 +/- 22 MU. The therapeutic effect started after 7.1 +/- 2.3 days and lasted for 12.5 +/- 3.9 weeks. It was stable throughout the observation period in 85% of all patients. Adverse effects occurred in 5.4% of injection series. No patient terminated treatment because of unsatisfactory results. Secondary therapy failure did not occur. With an effective conversion ratio of Botox:Dysport = 1:2.56 there were no differences between both drugs with respect to therapeutic efficacy and adverse effects thus confirming the hypothesis that there may not be intrinsic differences between both products.