Botulinum toxin for blepharospasm and hemifacial spasm: stability of duration of effect and dosage over time

Botulinum toxin A for patients with orofacial dystonia: prospective, observational, single-centre study

The objective of this study was to demonstrate the efficacy of intramuscular botulinum toxin type A (BTX-A) as a method of controlling the symptoms of focal facial dystonia. A prospective, longitudinal, observational, pre-post (case-series) single-centre study was conducted over a period of 3 months, involving 30 patients with focal dystonia. The patients were enrolled on a first-come, first-served basis. For all patients, the abnormal movements were evaluated using the Abnormal Involuntary Movement Scale (AIMS). The AIMS results were recorded immediately before BTX-A injection (primary predictor variable) and after 3 months (the toxin reaches its maximum effect 2 weeks after injection, and the effect is maintained for 3 months). An improvement in AIMS score was the primary outcome variable. Treatment efficacy was evaluated using the Pearson correlation index with a level of significance of P<0.05. The average age of the study subjects was 70.9±12.7years (20 female, 10 male). The mean dose of BTX-A used was 27.4±20.5U. The mean improvement in AIMS score after treatment was 5.2±4.2. A significant correlation was found between the dose applied and the reduction in AIMS score (P<0.05). BTX-A can be used in the treatment of focal dystonia and provides reproducible results.

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.

Clinical uses of botulinum neurotoxins: current indications, limitations and future developments

Botulinum neurotoxins (BoNTs) cause flaccid paralysis by interfering with vesicle fusion and neurotransmitter release in the neuronal cells. BoNTs are the most widely used therapeutic proteins. BoNT/A was approved by the U.S. FDA to treat strabismus, blepharospam, and hemificial spasm as early as 1989 and then for treatment of cervical dystonia, glabellar facial lines, axillary hyperhidrosis, chronic migraine and for cosmetic use. Due to its high efficacy, longevity of action and satisfactory safety profile, it has been used empirically in a variety of ophthalmological, gastrointestinal, urological, orthopedic, dermatological, secretory, and painful disorders. Currently available BoNT therapies are limited to neuronal indications with the requirement of periodic injections resulting in immune-resistance for some indications. Recent understanding of the structure-function relationship of BoNTs prompted the engineering of novel BoNTs to extend therapeutic interventions in non-neuronal systems and to overcome the immune-resistance issue. Much research still needs to be done to improve and extend the medical uses of BoNTs.

Long-term efficacy of botulinum a toxin for blepharospasm and hemifacial spasm

OBJECTIVE

To determine whether the duration of relief from symptoms in patients with essential blepharospasm (EB) or hemifacial spasm (HFS) who receive serial treatments with botulinum toxin type A (BtA) changes over the long-term.

METHODS

Retrospective longitudinal comparative analysis. The main outcome measure is the mean duration of relief from symptoms after an injection with BtA. Participants included 34 patients who received 30 or more serial BtA treatments for facial dyskinesia (EB or HFS). Repeated measures and linear regression analyses were used to determine trends and the mean duration of relief from symptoms was compared between early (first ten effective treatments) and late (last ten treatments) sessions in each group.

RESULTS

In the EB group (18 patients), the mean duration of relief was 13.5 weeks for the early and 11.4 weeks for the late sessions (P = 0.04). In the HFS group (16 patients) the mean duration of relief was 12.4 weeks in both treatment periods (P = 0.91). The duration of relief had a small negative correlation with mean late session BtA dose in the EB group (P = 0.03) but no correlation in the HFS group (P = 0.12).

CONCLUSIONS

There was a trend towards a decreased duration of relief from symptoms in patients with EB over the long-term, but no changes for HFS. The treatment remains effective in relieving symptoms and signs for both conditions.

Difference in response to botulinum toxin type A treatment between patients with benign essential blepharospasm and hemifacial spasm

BACKGROUND

Botulinum toxin (BTX) is the first-line treatment in managing benign essential blepharospasm (BEB) and hemifacial spasm (HFS). We wished to assess the difference in duration of effect and the number of BTX treatments required to treat patients with BEB and HFS.

METHODS

A prospective study of patients attending the BTX clinic in Manchester Royal Eye Hospital over 6 months. All treatments were administered by a single experienced ophthalmologist. A questionnaire was completed for each patient. In patients with BEB where the BTX was injected bilaterally, one side was randomized to compare with HFS patients. Patient demographics, cumulative dose of BTX, duration of BTX effect with patient satisfaction and the number of previous BTX injections were recorded.

RESULTS

Sixty-four patients were included in the study. The mean age was 60.8 years. Among them, 30 patients had BEB and 34 had HFS. Patients with HFS received a lower mean dose of BTX than patients with BEB (12.23 units vs. 16.2 units). The patients with HFS had a longer duration of effect than patients with BEB, with fewer BTX treatments. Of all patients, 90% with HFS and BEB were satisfied with the effect of their last BTX injection. Three unsatisfied patients in the BEB group were referred on for surgical management of their disorder.

CONCLUSIONS

We have shown that patients with BEB have a shorter duration of effect with BTX and require more frequent BTX treatments than patients with HFS, highlighting that facial dystonias in patients with BEB is more challenging to manage.

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

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 inter-group difference (P<0.0005, respectively). The mean (+/-SD) effect duration was statistically different (P=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=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=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 vsolder 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.

Effectiveness of repeated treatment with botulinum toxin type A across different conditions

This review assessed the overall effectiveness of repeated treatments with botulinum toxin type A (BoNTA) across different conditions, as documented in the published literature. Forty-four original research articles reporting on 16 different conditions were identified that included data on the duration or efficacy of multiple treatments with BoNTA. All of the 44 studies found sustained or enhanced improvement in efficacy and/or duration over the follow-up period, which ranged from a few treatments to more than 10 years. Dosages did not change over time in 22 of the studies, increased in 4 studies, were not reported over time in 17 studies, and tended to increase then decrease in one study. Seven studies reported a statistically significant increase in the efficacy or duration of BoNTA over time. Results suggest that continued benefit with repeated BoNTA treatment is widely reported in the literature.

Botulinum toxin therapy of hemifacial spasm: comparing different therapeutic preparations

Hemifacial spasm (HFS) is characterized by involuntary irregular clonic or tonic movements of the muscles innervated by cranial nerve VII on one side of the face, and is most often a result of vascular compression of the facial nerve at the root exit zone (Muscle and Nerve 1998;21:1740). Disability associated with this disorder ranges from social embarrassment to interference with vision resulting from involuntary eye closure. Treatment of HFS most often involves botulinum toxin injections, but may also include medications and surgery. We describe treatment with the three types of botulinum toxin currently commercially available--Botox, Dysport and Myobloc/NeuroBloc.

Blepharospasm and hemifacial spasm: a protocol for titration of botulinum toxin dose to the individual patient and for the management of refractory cases

PURPOSE

To evaluate a protocol for the treatment of facial dystonias.

METHOD

A retrospective noncomparative interventional case series of all patients who attended a specialised tertiary referral clinic between January 2000 and January 2003. At the start of treatment, patients were seen and treated at weekly intervals until their symptoms were controlled or they developed complications. The sum of the weekly doses was taken as the individual patient dose and then given at 3-4 monthly intervals as required for the individual patient. Refractory cases of spasm underwent orbicularis muscle reduction. Pretarsal spasm was treated with pretarsal botulinum toxin. If the spasm was relieved but the patient could not open their eyelids, a trial of ptosis props was undertaken and the toxin injections continued, before considering a brow suspension. If patients could not see because of a spastic Bell's phenomenon, they were given centrally acting systemic medication.

RESULTS

Of 182 new patients, 63 (35%) required two or more sets of injections to titrate their optimum dose of toxin. Symptoms improved in 169 patients (93%). Of a total 332 new patients and follow-up patients, 47 (14%) underwent surgery during their management, 36 protractor myectomy, and 13 brow suspension. Protractor myectomy improved symptoms in 23 (64%). Brow suspension improved symptoms in 12 patients (92%).

CONCLUSIONS

The dose of botulinum toxin can be titrated to the individual patient, and the refractory cases managed satisfactorily if a logical protocol is followed.

A randomized, placebo-controlled, crossover clinical trial of super blue-green algae in patients with essential blepharospasm or Meige syndrome

PURPOSE

To evaluate the effectiveness of super blue-green algae (SBGA) supplements on the severity of essential blepharospasm treated with botulinum toxin A injections.

DESIGN

Double-masked, placebo-controlled, two-period, crossover randomized trial.

PATIENTS AND METHODS

The study was carried out in patients with essential blepharospasm or Meige syndrome undergoing routine treatment with botulinum toxin A injections.

INTERVENTION

Patients were randomly assigned to either SBGA capsules or placebo. After 6 months of treatment, patients underwent a 6-month washout period with no treatment, then were administered the alternate treatment for an additional 6 months, thus serving as their own controls.

MAIN OUTCOME MEASURES

Video documentation of blink rate and involuntary facial movements, time between botulinum toxin A injections, and patients' subjective assessment of the impact of blepharospasm on functioning were obtained at the beginning and end of the first and second (crossover) treatment periods.

RESULTS

A total of 24 patients (10 men, 14 women; aged 42 to 83 years) completed both treatment periods. Mean within-patient difference in blink rate between SBGA and placebo periods was -2.1 blinks per 2 minutes (95% confidence interval [CI]: -20.8-+31.9), not statistically different from zero (P =.83). Mean within-patient difference in time between injections between SBGA and placebo periods was 4.6 days (95% CI: -13.3-+22.5), not statistically different from zero (P =.62). The lack of statistical significance may have been because of small sample size. There were no significant differences in severity of involuntary movement between SBGA and placebo treatment periods. However, patients were more likely to report limitation in function during the period they took SBGA than during the period they took placebo (odds ratio, 0.2; P =.03).

CONCLUSION

Overall, we found no evidence of a beneficial effect of SBGA as an adjunct to botulinum toxin A injections; however, a few patients, all younger than 60 years, did appear to benefit from SBGA.

Primary Blepharospasm

Primary blepharospasm is an adult-onset focal dystonia characterised by involuntary contractions of the orbicularis oculi muscles. Patients may have various types of movements arising from the different parts of the orbicularis oculi muscle. These include typical blepharospasm associated with Charcot's sign, pretarsal blepharospasm and flickering of the eyelids. Primary blepharospasm may be associated with so-called apraxia of eyelid opening as well as dystonia in the lower face, jaw or cervical muscles. Unless there are clinical clues to a symptomatic cause, adults presenting with blepharospasm do not require extensive aetiological investigation because the condition is rarely due to an identifiable condition. As the aetiology of primary blepharospasm is largely unknown, therapeutic approaches are symptomatic, with type A botulinum toxin being the treatment of choice.

The management of oromandibular motor disorders and facial spasms with injections of botulinum toxin

Although much work is yet to be done in this area, nine general conclusions can be derived: 1. Local site-of-injection side effects from botulinum toxin injections are rare, assuming proper technique is used. 2. The two most common medication-related side effects from botulinum toxin orofacial injections are alterations in salivary consistency and inadvertent weakness of the swallowing, speech, and facial muscles. These complications are injection site-specific (eg, more common with lateral pterygoid injections and palatal and tongue muscle injections) and dose-dependent problems. These problems are bothersome but are not contraindications for the therapy if it is needed. 3. The data presented in this article are mostly case series-based and open trial-based information that is promising, but randomized, blinded, controlled trials are needed to establish the true efficacy of this method for the orofacial motor and pain disorders. 4. The novice should begin with injection of muscles he or she can inject with low risk of incorrect placement. The hard-to-find muscles should be avoided when starting out. The novice clinician should inject and dissect a few cadavers to improve injection technique. 5. The general latency for botulinum toxin type A is 1 week, its duration is 2 to 3 months, and it is recommended that injection be done no more than once every 12 weeks to avoid development of antibodies against the toxin. 6. Depending on the target muscle, injection dose is 10 to 50 U of Botox type A per site with a total dose of 200 U in the masticatory system. More than this can be used (400 U maximum) if other sites in the head and neck are included in the injection protocol. 7. Regarding injecting painful muscles that do not exhibit palpable muscle hardness or EMG-determined spasticity or observable involuntary movements but have chronic myofascial trigger points or the patient localizes them as the site of their chronic daily headache pain, botulinum toxin injections might be helpful used in this manner, but conclusive data for this controversial application of botulinum toxin are still missing. 8. Hemifacial spasm has the largest number of open-label, clinical trials, some of which have a 10-year follow-up. The conclusions reached by all of these reports is that treatment of hemifacial spasm with repeated injections of botulinum toxin has been highly successful and that the dose and relative effect of the injections are stable over time. 9. Although EMG-guided injection may be useful, EMG is neither practical nor needed in most situations for orofacial injections because most of the orofacial muscles are easily palpable muscles or have definitive bony landmarks to help with the localization process.