A double-blind, randomized, comparative study of Dysport vs. Botox in primary palmar hyperhidrosis

From Toxin to Treatment: A Narrative Review on the Use of Botulinum Toxin for Autonomic Dysfunction

Since its regulatory approval over a half-century ago, botulinum toxin has evolved from one of the most potent neurotoxins known to becoming routinely adopted in clinical practice. Botulinum toxin, a highly potent neurotoxin produced by Clostridium botulinum, can cause botulism illness, characterized by widespread muscle weakness due to inhibition of acetylcholine transmission at neuromuscular junctions. The observation of botulinum toxin's anticholinergic properties led to the investigation of its potential benefits for conditions with an underlying etiology of cholinergic transmission, including autonomic nervous system dysfunction. These conditions range from disorders of the integument to gastrointestinal and urinary systems. Several formulations of botulinum toxin have been developed and tested over time, significantly increasing the availability of this treatment for appropriate clinical use. Despite the accelerated and expanded use of botulinum toxin, there lacks an updated comprehensive review on its therapeutic use, particularly to treat autonomic dysfunction. This narrative review provides an overview of the effect of botulinum toxin in the treatment of autonomic dysfunction and summarizes the different formulations and dosages most widely studied, while highlighting reported outcomes and the occurrence of any adverse events.

Efficacy and Safety Analysis of Botox Application and Iatrogenic Botulism: Panacea or Peril?

Clostridium botulinum toxin-A (BoNT-A) creates temporary paralysis in the muscles by acting on the muscle-nerve junction. It is injected into the mimic muscles when a decrease in the movements of the mimic muscles is desired. Despite many favorable applications, the use of BoNT-A is not without drawbacks. Although there is no expected serious side effect on health in BoNT-A treatments, various problems can be encountered in patients treated for aesthetic purposes. Botulism is a rare but potentially life-threatening syndrome, which is caused by the toxin produced by the bacterium Clostridium botulinum, which acts on the nervous system, vegetative forms of C. botulinum can only survive in anaerobic conditions, while spore forms are common in nature and can withstand harsh conditions. Botulism can stem from bacterial spores which release toxin in the body; in the form of enteric botulism, and wound botulism. The cases that develop 'iatrogenic botulism' after such procedures are usually those receiving high-dose toxin for therapeutic purposes. The treatment of botulism mainly consists of anti-toxin therapy and, if necessary, intensive care to prevent organ failures, including respiratory support. This article aims to cover all these issues related to botulism and other adverse outcomes related to BoNT-A injection in light of the most recent literature.

Iatrogenic Botulism: A Case Treated With Botulinum Antitoxin

OBJECTIVE

Botulinum toxin type A is widely used for the treatment of spasticity, focal dystonia, hemifacial spasm, hyperhidrosis, strabismus, chronic migraine, and also cosmetic purposes. Therapeutic use is commonly effective and safe. However, if toxin enters the vascular space and gets through to peripheral cholinergic nerve terminals, it may lead to iatrogenic botulism.

METHOD

We presented a patient who is diagnosed as iatrogenic botulism and treated with antitoxin at the 15th day of the exposure.

RESULTS

After the antitoxin administration, dramatical response to the treatment was observed.

CONCLUSIONS

In this report, we want to evaluate a new case of iatrogenic botulism and emphasize the importance of antitoxin administration regardless the timing of the exposure for patients with progressing paralysis.

Off-Label Use of Botulinum Toxin in Dermatology—Current State of the Art

Botulinum toxin (BoNT) is a neurotoxin produced by the Clostridium botulinum bacteria. Among seven different isoforms, only BoNT-A and BoNT-B are commercially used. Currently, botulinum toxin has been indicated by the U.S. Food and Drug Administration in several disorders, among others: chronic migraine, hyperhidrosis, urinary incontinence from detrusor overactivity, or cosmetics. However, there are numerous promising reports based on off-label BTX usage, indicating its potential effectiveness in other diseases, which remains unknown to many. Among them, dermatological conditions, such as rosacea, annal fissure, Raynaud phenomenon, hypertrophic scars and keloids, and also hidradenitis suppurativa, are currently being investigated. This article aims to provide a comprehensive update on the off-label use of botulinum toxin in dermatology, based on an analysis and summary of the published literature.

Botulinum Toxin Injections for Leg Contouring in East Asians

BACKGROUND

A common aesthetic concern among East Asian women is enlarged calves. Although surgical resection has been a traditional treatment option, botulinum toxin injections into the gastrocnemius muscle are an emerging, noninvasive alternative.

OBJECTIVE

To perform a literature review on botulinum toxin injections for leg contouring.

MATERIALS AND METHODS

A literature review was conducted using PubMed, Web of Science, Embase, and Cochrane's CENTRAL database to identify articles relating to combinations of the terms botulinum toxin, gastrocnemius, calves, and leg contouring.

RESULTS

Based on the limited publications to date, the authors prepared a review on how to treat an enlarged calf with botulinum toxin including injection techniques, anticipated efficacy, outcome monitoring, and potential side effects.

CONCLUSION

Botulinum toxin injections for calf reduction are an emerging, noninvasive treatment option. Studies to date suggest that it is an efficacious method with few immediate side effects. Future areas for investigation include defining the criteria for calf hypertrophy, minimum effective dosage of botulinum toxin, and the potential long-term effects of injections.

Alternative Clinical Indications of Botulinum Toxin

Botulinum toxin type A (BoNTA) is a powerful neurotoxin that inhibits acetylcholine release from presynaptic vesicles. The potency and safety profile of BoNTA grant the toxin vast therapeutic potential. It has been used off-label for a variety of dermatologic conditions. This review aims to analyze published literature regarding the benefits and risks of the off-label use of BoNTA beyond facial lines, including eccrine hidrocystomas, enlarged pores, keloids and hypertrophic scars, hidradenitis suppurativa, hyperhidrosis, masseter muscle hypertrophy, and salivary gland hypertrophy, among others. A MEDLINE search from January 2000 to December 2019 was conducted on the off-label uses of botulinum toxin in dermatology.

Botulinum toxin: Pharmacology and injectable administration for the treatment of primary hyperhidrosis

Hyperhidrosis is a dermatological condition defined by excessive sweating beyond thermoregulatory needs with significant effects on patients' quality of life. Hyperhidrosis is categorized as primary or secondary: primary hyperhidrosis is mostly focal and idiopathic, whereas secondary hyperhidrosis is commonly generalized and caused by an underlying medical condition or use of medications. Various surgical and nonsurgical therapies exist for primary hyperhidrosis. Although botulinum toxin is one of the deadliest toxins known, when used in small doses, it is one of the most effective therapies for primary hyperhidrosis. Botulinum toxin injections are widely used as a second-line primary hyperhidrosis treatment option once topical treatment strategies have failed. This article provides an overview of the commercially available botulinum toxin formulations and their applications in the treatment of primary hyperhidrosis.

Injectable and topical neurotoxins in dermatology: Indications, adverse events, and controversies

The use of neuromodulators for therapeutic and cosmetic indications has proven to be remarkably safe. While aesthetic and functional adverse events are uncommon, each anatomic region has its own set of risks of which the physician and patient must be aware before treatment. The therapeutic usages of botulinum toxins now include multiple specialties and multiple indications. New aesthetic indications have also developed, and there has been an increased utilization of combination therapies to combat the effects of global aging. In the second article in this continuing medical education series, we review the prevention and treatment of adverse events, therapeutic and novel aesthetic indications, controversies, and a brief overview of combination therapies.

Safety of available and emerging drug therapies for hyperhidrosis

INTRODUCTION

Hyperhidrosis affects 4.8% of the U.S. population and has been underestimated by physicians for long time despite considerable interference with quality of life. Many patients suffer from primary (idiopathic) hyperhidrosis which results from over-activity of sympathetic nerves and is restricted to specific body areas, mostly the axillae, palms, soles, or head. Secondary hyperhidrosis is caused by an underlying disease or the intake of medications and often involves large parts of the body. Numerous effective therapies with topical or systemic drugs and surgical options are available. Areas covered: Efficacy and safety data on aluminum salts, anticholinergic drugs for topical or systemic application, and on intradermal botulinum toxin injections used to treat hyperhidrosis are critically evaluated, including data from clinical trials with focus on possible side effects and long-term complications in dispute. Expert opinion: Hyperhidrosis often responds well to available therapies. Depending on the type of hyperhidrosis treatment should be topical/local or systemic. Most of the side effects are mild, transient and easily manageable. In case of systemic treatment with anticholinergics low dosing and up-titration of medication is necessary to avoid severe adverse effects. Concerns about the promotion of breast cancer and Alzheimer disease by topical aluminum salts are unsolved.

Current and Emerging Medical Therapies for Primary Hyperhidrosis

Hyperhidrosis is defined as the production of sweat beyond what is physiologically necessary to maintain thermal homeostasis. This disease state may (and typically does) have a significant impact on the patient’s quality of life. Medications including antiperspirants, anticholinergics, and botulinum toxin have been shown to be effective in the management of hyperhidrosis. Several medical device technologies have also proven to be effective. This review article will explore the current and emerging pharmacological and medical device treatments for hyperhidrosis and provide a framework for treating patients who suffer with primary forms of hyperhidrosis.

Efficacy of botulinum toxin type B for the treatment of primary palmar hyperhidrosis: a prospective, open, single-blind, multi-centre study

Primary palmar hyperhidrosis is a distressing and disabling condition that can produce social, psychological and occupational problems. Although the use of botulinum toxin type A (BoNT-A) has been reported as an efficacious and safe intervention to improve palmar hyperhidrosis, only one study concerned botulinum toxin type B (BoNT-B) in this disorder. The aim of study was to evaluate the efficacy and safety of BoNT-B in treating primary palmar hyperhidrosis. Participants were injected with 5,000 IU of BoNT-B in each palm. Visual analogue test (VAS) to evaluate the intensity of decrease in sweat production, Minor's iodine starch test and measurement of paper towels' weight were used to ascertain palmar sweating at baseline, 4, 12 and 24 weeks after BoNT-B injections by a blind examiner. Thirty-two subjects (12 males, 20 females, mean age 31 ± 11) were enrolled. Significant reduction of palmar sweating was detected after BoNT-B injection: 2.9 ± 1.4, 0.3 ± 0.4, 0.9 ± 0.8, and 2.1 ± 1.5 g (p < 0.001) of paper towels' weight for the right palm at baseline, 4, 12 and 24 weeks; and 2.8 ± 1.7, 0.5 ± 0.6, 0.8 ± 0.7, and 1.8 ± 1.25 g (p < 0.001) at same time, respectively for the left palm. Significant reduction of mean VAS values were also detected after BoNT-B injections: 8.6 ± 1.1, 0.6 ± 0.8, 3.5 ± 2.5, and 7.1 ± 2.4 (p < 0.0001) at baseline, 4, 12 and 24 weeks, respectively. Mild side effects consisting in local pain and hand weakness were observed in 4 (12.5%) subjects. The findings indicated that the use of 5,000 IU BoNT-B injection in each palm was safe and significantly improved the severity of palmar hyperhidrosis.

Efficacy of Onabotulinum Toxin A (Botox) versus Abobotulinum Toxin A (Dysport) Using a Conversion Factor (1 : 2.5) in Treatment of Primary Palmar Hyperhidrosis

Background. Two preparations of botulinum A toxin (BTX-A) are commercially available for the treatment of palmar hyperhidrosis (PPH): Botox (Allergan; 100 U/vial) and Dysport (Ipsen Limited; 500 U/vial), which are not bioequivalent. Results regarding an appropriate conversion factor between them are controversial. Objectives. This paper aims to compare the efficacy of Botox and Dysport in PPH using a conversion factor of 1 : 2.5. Methods. Eight patients with severe PPH received intradermal injections of Botox in one palm and Dysport in the other in the same session. Clinical assessment was performed at baseline and posttreatment for 8 months using Minor's iodine starch test, Hyperhidrosis Disease Severity Scale (HDSS), and Dermatology Life Quality Index (DLQI) test. Results. At 3 weeks, a significant decrease in sweating for both preparations was noted which was more pronounced with Dysport compared with Botox. At 8 weeks, this difference turned insignificant. Continued evaluation showed similar improvement in both palms with a nonsignificant difference. Patients with longer disease duration were more liable to relapse. Conclusion. The efficacy and safety of Botox and Dysport injections were similar using a conversion factor of 1 : 2.5. There was a trend towards a more rapid action after Dysport treatment but without significant importance.

Suture boots: an aid for the injection of onabotulinum toxin a for primary focal hyperhidrosis

Primary focal hyperhidrosis is a difficult problem for adults, children, and adolescents, causing significant impairment in quality of life. Onabotulinum toxin A injection is an effective third-line treatment for primary focal hyperhidrosis. Here we describe a technique to ensure adequate depth of botulinum toxin placement in the dermis using suture boots as an aid for injection.

Hyperhidrosis: anatomy, pathophysiology and treatment with emphasis on the role of botulinum toxins

Clinical features, anatomy and physiology of hyperhidrosis are presented with a review of the world literature on treatment. Level of drug efficacy is defined according to the guidelines of the American Academy of Neurology. Topical agents (glycopyrrolate and methylsulfate) are evidence level B (probably effective). Oral agents (oxybutynin and methantheline bromide) are also level B. In a total of 831 patients, 1 class I and 2 class II blinded studies showed level B efficacy of OnabotulinumtoxinA (A/Ona), while 1 class I and 1 class II study also demonstrated level B efficacy of AbobotulinumtoxinA (A/Abo) in axillary hyperhidrosis (AH), collectively depicting Level A evidence (established) for botulinumtoxinA (BoNT-A). In a comparator study, A/Ona and A/Inco toxins demonstrated comparable efficacy in AH. For IncobotulinumtoxinA (A/Inco) no placebo controlled studies exist; thus, efficacy is Level C (possibly effective) based solely on the aforementioned class II comparator study. For RimabotulinumtoxinB (B/Rima), one class III study has suggested Level U efficacy (insufficient data). In palmar hyperhidrosis (PH), there are 3 class II studies for A/Ona and 2 for A/Abo (individually and collectively level B for BoNT-A) and no blinded study for A/Inco (level U). For B/Rima the level of evidence is C (possibly effective) based on 1 class II study. Botulinum toxins (BoNT) provide a long lasting effect of 3–9 months after one injection session. Studies on BoNT-A iontophoresis are emerging (2 class II studies; level B); however, data on duration and frequency of application is inconsistent.

Efficacy and safety of a novel botulinum toxin type A product for the treatment of moderate to severe glabellar lines: a randomized, double-blind, active-controlled multicenter study

BACKGROUND

A new botulinum toxin type A (NBoNT) produced from the same strain of Clostridium botulinum as onabotulinumtoxinA (OBoNT) is widely used in Asia.

OBJECTIVES

To compare the efficacy and safety of NBoNT and OBoNT for moderate to severe glabellar wrinkles.

METHODS

A double-blind, randomized, active-controlled, phase III study was performed. Three hundred fourteen patients were randomized at a 1:1 ratio to receive 20 U of toxin. The primary end point was the responder rate according to investigator live assessment at maximum frown at week 4. Secondary end points were responder rates according to investigator live assessment with frowning and at rest at weeks 8, 12, and 16, with additional photographic assessment by a panel of blinded raters 4 weeks after injection. Subjective satisfaction scores were also evaluated.

RESULTS

Four weeks after treatment, responder rates for maximum frown were 93.7% (133/142) in the NBoNT group and 94.5% (138/146) in the OBoNT group. For secondary end points, there was no significant difference between the two groups for any variable at any time point. Noninferiority of NBoNT was confirmed. There were no serious adverse effects with either toxin.

CONCLUSION

NBoNT is equally as effective as OBoNT for the treatment of glabellar frown lines. Both toxins were well tolerated.

Pocketed microneedles for rapid delivery of a liquid-state botulinum toxin A formulation into human skin

Botulinum toxin A (BT) is used therapeutically for the treatment of primary focal hyperhidrosis, a chronic debilitating condition characterised by over-activity of the eccrine sweat glands. Systemic toxicity concerns require BT to be administered by local injection, which in the case of hyperhidrosis means multiple painful intradermal injections by a skilled clinician at 6-monthly intervals. This study investigates the potential of a liquid-loaded pocketed microneedle device to deliver botulinum toxin A into the human dermis with the aim of reducing patient pain, improving therapeutic targeting and simplifying the administration procedure. Initially, β-galactosidase was employed as a detectable model for BT to (i) visualise liquid loading of the microneedles, (ii) determine residence time of a liquid formulation on the device and (iii) quantify loaded doses. An array of five stainless steel pocketed microneedles was shown to possess sufficient capacity to deliver therapeutic doses of the potent BT protein. Microneedle-mediated intradermal delivery of β-galactosidase and formaldehyde-inactivated botulinum toxoid revealed effective deposition and subsequent diffusion within the dermis. This study is the first to characterise pocketed microneedle delivery of a liquid formulation into human skin and illustrates the potential of such systems for the cutaneous administration of potent proteins such as BT. A clinically appropriate microneedle delivery system for BT could have a significant impact in both the medical and cosmetic industries.

Evidence-based review and assessment of botulinum neurotoxin for the treatment of secretory disorders

Botulinum neurotoxin (BoNT) can be injected to achieve therapeutic benefit across a large range of clinical conditions. To assess the efficacy and safety of BoNT injections for the treatment of certain hypersecretory disorders, including hyperhidrosis, sialorrhea, and chronic rhinorrhea, an expert panel reviewed evidence from the published literature. Data sources included English-language studies identified via MEDLINE, EMBASE, CINAHL, Current Contents, and the Cochrane Central Register of Controlled Trials. Evidence tables generated in the 2008 Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (AAN) review of the use of BoNT for autonomic disorders were also reviewed and updated. The panel evaluated evidence at several levels, supporting BoNT as a class, the serotypes BoNT-A and BoNT-B, as well as the four individual commercially available formulations: abobotulinumtoxinA (A/Abo), onabotulinumtoxinA (A/Ona), incobotulinumtoxinA (A/Inco), and rimabotulinumtoxinB (B/Rima). The panel ultimately made recommendations for each therapeutic indication, based upon the strength of clinical evidence and following the AAN classification scale. For the treatment of axillary hyperhidrosis in a total of 923 patients, the evidence supported a Level A recommendation for BoNT-A, with a Level B recommendation for A/Abo and A/Ona and a Level U recommendation (insufficient data) for A/Inco and B/Rima. Five trials in 82 patients supported the use of BoNT in palmar hyperhidrosis, with a Level B recommendation for BoNT-A and a Level C recommendation for BoNT-B; individual formulations received a Level U rating due to insufficient data. BoNT (and all individual formulations) received a Level U recommendation for the treatment of gustatory sweating. Support for use of BoNT in sialorrhea was derived from eight trials in a total of 222 adults and children. Evidence supported a Level B recommendation for A/Abo, A/Ona, and B/Rima and a Level U recommendation for A/Inco. Evidence supported a Level B recommendation for A/Ona for the treatment of allergic rhinitis, based on two Class II studies in 73 patients. A lack of published studies for A/Abo, A/Inco, or B/Rima supported a Level U recommendation for those formulations. Further clarity on the optimal mode of administration and additional studies using other BoNT formulations are needed to fill current evidence gaps.

Complications of minimally invasive cosmetic procedures: prevention and management

Over the past decade, facial rejuvenation procedures to circumvent traditional surgery have become increasingly popular. Office-based, minimally invasive procedures can promote a youthful appearance with minimal downtime and low risk of complications. Injectable botulinum toxin (BoNT), soft-tissue fillers, and chemical peels are among the most popular non-invasive rejuvenation procedures, and each has unique applications for improving facial aesthetics. Despite the simplicity and reliability of office-based procedures, complications can occur even with an astute and experienced injector. The goal of any procedure is to perform it properly and safely; thus, early recognition of complications when they do occur is paramount in dictating prevention of long-term sequelae. The most common complications from BoNT and soft-tissue filler injection are bruising, erythema and pain. With chemical peels, it is not uncommon to have erythema, irritation and burning. Fortunately, these side effects are normally transient and have simple remedies. More serious complications include muscle paralysis from BoNT, granuloma formation from soft-tissue filler placement and scarring from chemical peels. Thankfully, these complications are rare and can be avoided with excellent procedure technique, knowledge of facial anatomy, proper patient selection, and appropriate pre- and post-skin care. This article reviews complications of office-based, minimally invasive procedures, with emphasis on prevention and management. Practitioners providing these treatments should be well versed in this subject matter in order to deliver the highest quality care.

Treatment options for hyperhidrosis

Hyperhidrosis is a disorder of excessive sweating beyond what is expected for thermoregulatory needs and environmental conditions. Primary hyperhidrosis has an estimated prevalence of nearly 3% and is associated with significant medical and psychosocial consequences. Most cases of hyperhidrosis involve areas of high eccrine density, particularly the axillae, palms, and soles, and less often the craniofacial area. Multiple therapies are available for the treatment of hyperhidrosis. Options include topical medications (most commonly aluminum chloride), iontophoresis, botulinum toxin injections, systemic medications (including glycopyrrolate and clonidine), and surgery (most commonly endoscopic thoracic sympathectomy [ETS]). The purpose of this article is to comprehensively review the literature on the subject, with a focus on new and emerging treatment options. Updated therapeutic algorithms are proposed for each commonly affected anatomic site, with practical procedural guidelines. For axillary and palmoplantar hyperhidrosis, topical treatment is recommended as first-line treatment. For axillary hyperhidrosis, botulinum toxin injections are recommended as second-line treatment, oral medications as third-line treatment, local surgery as fourth-line treatment, and ETS as fifth-line treatment. For palmar and plantar hyperhidrosis, we consider a trial of oral medications (glycopyrrolate 1-2 mg once or twice daily preferred to clonidine 0.1 mg twice daily) as second-line therapy due to the low cost, convenience, and emerging literature supporting their excellent safety and reasonable efficacy. Iontophoresis is considered third-line therapy for palmoplantar hyperhidrosis; efficacy is high although so are the initial levels of cost and inconvenience. Botulinum toxin injections are considered fourth-line treatment for palmoplantar hyperhidrosis; efficacy is high though the treatment remains expensive, must be repeated every 3-6 months, and is associated with pain and/or anesthesia-related complications. ETS is a fifth-line option for palmar hyperhidrosis but is not recommended for plantar hyperhidrosis due to anatomic risks. For craniofacial hyperhidrosis, oral medications (either glycopyrrolate or clonidine) are considered first-line therapy. Topical medications or botulinum toxin injections may be useful in some cases and ETS is an option for severe craniofacial hyperhidrosis.

Retrospective evaluation of the dose equivalence of Botox(®) and Dysport (®) in the management of blepharospasm and hemifacial spasm: a novel paradigm for a never ending story

Botox(®) and Dysport(®) are the preparations of botulinum neurotoxin most widely used for therapeutic purposes. Several studies have addressed the topic of the equivalency ratio (D/B ratio) to be used in clinical practice and whether a reliable value exists is still a matter of debate. To this purpose, we ideated a novel paradigm by retrospectively examining the patients affected by hemifacial spasm and blepharospasm. We compared the pairs of treatments with a switch from one brand to the other undergone by the same patient in consecutive sessions with overlapping clinical outcome. Out of 2006 treatments, we found 51 treatment pairs. D/B ratio was extremely variable (range 1.2-13.3) and in most cases (65%) it was between 1:3 and 1:5. In conclusion, even if the 1:4 ratio might be reliable for clinical purpose, a true bioequivalence between Dysport(®) and Botox(®) might not exist due to the intrinsic difference in their pharmacokinetic properties.

Gummy smile and botulinum toxin: a new approach based on the gingival exposure area

BACKGROUND

Gummy smile (GS) is an aesthetic disorder for some patients, which can be corrected by injection of botulinum toxin.

OBJECTIVE

We sought to classify GS according to the area of gingival exposure and the respective muscles involved in order to perfect the botulinum toxin injection technique for each patient.

METHODS

Sixteen patients with GS were evaluated before receiving botulinum toxin injections. Based on the area of excessive gum displayed and identification of the muscles involved, 4 different types of GS were identified: anterior, posterior, mixed, and asymmetric. AbobotulinumtoxinA (Dysport, Ipsen Biopharm Limited, Wrexham, UK) was injected using a different injection technique for each type of GS, based on the main muscles involved. With the aid of two computer programs, the area of gum exposed was measured before and after the application of abobotulinumtoxinA, to evaluate the level of improvement.

RESULTS

There was a decrease in the degree of gum display in all patients. The general average improvement achieved was 75.09%. Two patients showed slight adverse effects that were easily corrected with additional doses of abobotulinumtoxinA.

LIMITATIONS

For this study, there was no sample size calculation and no statistical analysis of the cases.

CONCLUSION

The authors conclude that it is important to identify the type of GS and therefore the main muscles involved, so that the correct injection technique can be used. AbobotulinumtoxinA was shown to be effective and safe for use in all types of GS in the present sample.

A single-centre retrospective review of unilateral and bilateral Dysport injections in adductor spasmodic dysphonia

We reviewed the results and side-effect profile of the Dysport preparation of botulinum toxin A (BTA) in the management of the adductor spasmodic dysphonia. We performed 272 injection episodes in 68 patients, 42 (62%) female, 26 (38%) male. A total of 116 of these injections were unilateral, and 156 were bilateral; 94% of the injections were considered to have been successful with a voice score of 2 or higher. The mean duration of effect (injection intervals) was 128.8 days in the unilateral cohort and 118.7 days in the bilateral (P > 0.05). We injected a relatively lower dose of BTA for unilateral injection episodes in our institution compared to those reported by others to produce comparable results and side-effect profiles.

Botulinum toxin: examining duration of effect in facial aesthetic applications

Patient satisfaction with botulinum toxin treatment is a key success factor in aesthetic procedures and is governed by the interaction of numerous variables. Duration of effect is important because it influences retreatment intervals as well as affecting cost and convenience to the patient. In order to review the evidence on the duration of benefit associated with various commercial formulations of botulinum toxin, MEDLINE was searched using the following terms: 'botulinum' and 'duration'/'retreatment' (limits: 'clinical trials,' 'meta-analyses,' 'English'). I also searched my existing reference files, reference lists of identified articles, and meeting/conference abstracts to ensure completeness. The focus was on clinical medicine and aesthetic trials. To be eligible for the analysis, studies had to include efficacy assessments at multiple timepoints. To estimate duration of benefit, the following outcomes were examined and summarized: responder rates, mean wrinkle severity scores at various timepoints (with or without changes from baseline), and relapse rates. Duration at both repose and maximum attempted muscle contraction was considered when provided. Where possible, duration was assessed by formulation and dose. The initial search yielded 164 articles. Of these, 35 included an adequate measure of duration in aesthetic indications. The majority of these (22) were on the glabellar area. Study designs and endpoints were highly heterogeneous, and duration of effect varied between studies. Several studies with the BOTOX Cosmetic (onabotulinumtoxinA; Allergan, Inc., Irvine, CA, USA) formulation of botulinum toxin type A (BoNTA) included relapse rates, defined conservatively as return to baseline levels of line severity for two consecutive visits approximately 30 days apart (at repose and maximum contraction). In these studies, duration of effect ranged from 3 to 5 months in female patients and from 4 to 6 months in male patients. Individual patients had longer durations of response. Across all studies providing relapse rates, most patients relapsed by 6 months. In studies assessing patient satisfaction, satisfaction remained high throughout the duration of the studies ( approximately 4 months). With the Dysport formulation (abobotulinumtoxinA, clostridium botulinum type A toxin-hemagglutinin complex; Ipsen Biopharm Ltd, Wrexham, England), retreatment intervals were estimated at a mean of 3.9 months (median = 3.3 months). These results were consistent with responder rates from another Dysport study in which the active treatment differed from placebo at 3 but not 4 months. A single comparative study demonstrated that the proportion of patients relapsing at week 16 was 23% (95% CI 11.5, 41.6) in the BOTOX Cosmetic group as compared with 40% (95% CI 25.2, 60.1) in the Dysport group. Myobloc (rimabotulinumtoxinB, botulinum toxin type B; Solstice Neurosciences, Inc., South San Francisco, CA, USA) was associated with shorter durations of action (2-3 months). Data from facial areas other than the glabella, although more limited, supported a duration of at least 3-4 months. The addition of BoNTA to dermal fillers or light/laser therapy appeared to increase the degree of effect. Repeated BoNTA treatments may prolong duration of effect or potentiate the effect. In conclusion, patients can expect treatments to last > or =3 months but often as many as 4-5 months depending on the facial area, dose, and formulation. Additional research should help clarify the impact of age, baseline rhytid severity, patient sex, repeated treatments, and combination treatment on longevity of effect.

Practice parameter: pharmacologic treatment of spasticity in children and adolescents with cerebral palsy (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology and the Practice Committee of the Child Neurology Society

OBJECTIVE

To evaluate published evidence of efficacy and safety of pharmacologic treatments for childhood spasticity due to cerebral palsy.

METHODS

A multidisciplinary panel systematically reviewed relevant literature from 1966 to July 2008.

RESULTS

For localized/segmental spasticity, botulinum toxin type A is established as an effective treatment to reduce spasticity in the upper and lower extremities. There is conflicting evidence regarding functional improvement. Botulinum toxin type A was found to be generally safe in children with cerebral palsy; however, the Food and Drug Administration is presently investigating isolated cases of generalized weakness resulting in poor outcomes. No studies that met criteria are available on the use of phenol, alcohol, or botulinum toxin type B injections. For generalized spasticity, diazepam is probably effective in reducing spasticity, but there are insufficient data on its effect on motor function and its side-effect profile. Tizanidine is possibly effective, but there are insufficient data on its effect on function and its side-effect profile. There were insufficient data on the use of dantrolene, oral baclofen, and intrathecal baclofen, and toxicity was frequently reported.

RECOMMENDATIONS

For localized/segmental spasticity that warrants treatment, botulinum toxin type A should be offered as an effective and generally safe treatment (Level A). There are insufficient data to support or refute the use of phenol, alcohol, or botulinum toxin type B (Level U). For generalized spasticity that warrants treatment, diazepam should be considered for short-term treatment, with caution regarding toxicity (Level B), and tizanidine may be considered (Level C). There are insufficient data to support or refute use of dantrolene, oral baclofen, or continuous intrathecal baclofen (Level U).

Unilateral versus bilateral thyroarytenoid Botulinum toxin injections in adductor spasmodic dysphonia: a prospective study

Objectives

In this preliminary prospective study, we compared unilateral and bilateral thyroarytenoid muscle injections of Botulinum toxin (Dysport) in 31 patients with adductor spasmodic dysphonia, who had undergone more than 5 consecutive Dysport injections (either unilateral or bilateral) and had completed 5 concomitant self-rated efficacy and complication scores questionnaires related to the previous injections. We also developed a Neurophysiological Scoring (NPS) system which has utility in the treatment administration.

Method and materials

Data were gathered prospectively on voice improvement (self-rated 6 point scale), length of response and duration of complications (breathiness, cough, dysphagia and total voice loss). Injections were performed under electromyography (EMG) guidance. NPS scale was used to describe the EMG response. Dose and unilateral/bilateral injections were determined by clinical judgment based on previous response. Time intervals between injections were patient driven.

Results

Low dose unilateral Dysport injection was associated with no significant difference in the patient's outcome in terms of duration of action, voice score (VS) and complication rate when compared to bilateral injections. Unilateral injections were not associated with any post treatment total voice loss unlike the bilateral injections.

Conclusion

Unilateral low dose Dysport injections are recommended in the treatment of adductor spasmodic dysphonia.

[Different botulinum toxins and their specifications]

Botulinum neurotoxin A was the first developed for therapeutic and then esthetic uses, Botox first and then Dysport. These two products differ on a few points, explaining their nonequivalence of units: American and British tests of the mouse LD50 units based on solutions that were not identical and 500microg vs 150microg serum albumin dose in the excipient. The neurotoxin- accessory protein complexes were also different: 900 kDa homogeneous for Botox, 500 kDa heterogeneous for Dysport, giving greater diffusion for Dysport, but this is under debate and could result from an excessive conversion ratio. Clinical comparative studies, often with weak methodology, have defined an ideal ratio between these two products, guaranteeing efficacy, but without an overly pronounced diffusion. In the first publications for neurological and ophthalmological indications, the conversion ratio between Dysport and Botox was high, 4:1, and sometimes higher. However, today, particularly for cosmetic indications, the trend is toward a much lower ratio, 2.5:1, or perhaps less for dyshidrosis. This lower ratio has an economic incidence: Dysport is less expensive and therefore more competitive. The price of Dysport's cosmetic product, Azzalure, compared to the price of Vistabel, which is Botox's cosmetic presentation, has not yet been defined in France. The other A toxins, Xeomin, and the Asian toxins, MyoBloc (botulinum toxin type B), tested compared to Botox, have a slightly lower efficacy.

Bilateral thoracoscopic T2 to T3 sympathectomy versus botulinum injection in palmar hyperhidrosis

BACKGROUND

Bilateral T2 to T3 thoracoscopic sympathectomy and injection of botulinum toxin-A are presently the most effective modalities in the treatment of primary palmar hyperhidrosis. In this study we evaluated comparative merits of the two therapies.

METHODS

Patients suffering primary palmar hyperhidrosis were treated by either bilateral T2 to T3 thoracoscopic sympathectomy (n = 68) or by injection of botulinum toxin-A (n = 86). The groups were homogeneous for relevant demographic, physiologic, and clinical data. Quantification of sweat production was performed by Minor's iodine starch and glove tests. Subjective changes were assessed by quality of life questionnaires (Hyperhidrosis, Dermatology Life Quality Index, Short Form-36, Nottingham's Health Profile) and patient's satisfaction self-assessment. A cost comparison between groups was also carried out.

RESULTS

No operative mortality or major morbidity was recorded in either group. Minor's test showed a more significant reduction in the surgical group: +94% versus +63% at 6 months and +94% versus +30% at 12 months. Compensatory sweating was significantly greater and long-lasting in the surgical group. All subjective tests improved rapidly and significantly in both groups. After 6 months, results mildly worsened in the surgical group and more significantly in the botulinum group. Patient's satisfaction was initially greater in the botulinum group (p = 0.03), but after 6 months it significantly reversed (p = 0.04). Surgical treatment cost approximately as much as four botulinum treatments.

CONCLUSIONS

Thoracoscopic sympathectomy is superior to botulinum toxin-A injection. The greater initial costs and discomfort are offset by a greater reduction in compensatory sweating.

Botulinum toxin A treatment for contouring of the lower leg

BACKGROUND

Botulinum toxin type A is widely used in the treatment of bilateral masseteric hypertrophy in Asians. Botulinum toxin A may have plausible effects on the oversized calf muscles that cause mental distress in Korean women.

OBJECTIVE

We report our successful use of botulinum toxin A in the treatment of two patients with muscular legs.

METHODS

The toxin was injected into the gastrocnemius muscle, 300-360 U per side.

RESULTS

A reduction in calf circumference was noticed 3 weeks after treatment and was maintained for 6-8 months without systemic side effects.

CONCLUSION

Botulinum toxin treatment for enlarged gastrocnemius muscles is a non-invasive alternative method for the improvement of calf contours.

Dose equivalence of two commercial preparations of botulinum neurotoxin type A: time for a reassessment?

BACKGROUND

The units of different preparations of botulinum neurotoxin type A (BoNT-A) have different potencies, and dosing recommendations for each product are not interchangeable. Historically, there has been debate concerning the dose-equivalence ratio that should be used in clinical practice.

METHODS

Published evidence was considered to establish an appropriate dose-conversion ratio for the two main commercially available preparations of BoNT-A--Dysport (Dp) and Botox (Bx).

RESULTS

Four key areas of evidence were identified: nonclinical and preclinical studies; studies exploring the diffusion characteristics and effects of complexing proteins; comparative experimental data from human studies; and clinical studies. Nonclinical data indicate that the principal reasons for differences in unit potency between the two products are dilution artefacts in the mouse assay. Use of saline as a diluent, at high dilutions, results in significant loss of potency in the Bx assay, whereas use of gelatin phosphate buffer in the Dp assay procedure protects the toxin during dilution. The published data on mouse assays show a Dp : Bx unit ratio range of 2.3-2.5 : 1 in saline and 1.8-3.2 : 1 in gelatin phosphate buffer. Data indicate that complexing proteins or size of the complex, which is highly pH sensitive, play no role in toxin diffusion and that Dp and Bx have similar diffusion characteristics when used at comparable doses. Randomized, controlled clinical studies indicate that 3 : 1 is more appropriate than 4 : 1, but the two products are not equivalent at this ratio. Comparative human experimental studies using the extensor digitorum brevis test, facial lines and anhidrotic action halo tests support dose-conversion ratios less than 3 : 1.

LIMITATIONS

Data comparing dose equivalence ratios from the non-clinical setting should be extrapolated into the clinical setting with some caution.

CONCLUSIONS

Dose-conversion ratios between Dp and Bx of 4 : 1 and greater are not supported by the recent literature.

Botulinum toxin for hyperhidrosis: a review

Primary focal hyperhidrosis is a disorder of idiopathic excessive sweating that typically affects the axillae, palms, soles, and face. The disorder, which affects up to 2.8% of the US population, is associated with considerable physical, psychosocial, and occupational impairments. Current therapeutic strategies include topical aluminum salts, tap-water iontophoresis, oral anticholinergic agents, local surgical approaches, and sympathectomies. These treatments, however, have been limited by a relatively high incidence of adverse effects and complications. Non-surgical treatment complications are typically transient, whereas those of surgical therapies may be permanent and significant. Recently, considerable evidence suggests that botulinum toxin type A (BTX-A) injections into hyperhidrotic areas can considerably reduce focal sweating in multiple areas without major adverse effects. BTX-A has therefore shown promise as a potential replacement for more invasive treatments after topical aluminum salts have failed. This article reviews the epidemiology, diagnosis, and management of primary focal hyperhidrosis, with an emphasis on recent research evidence supporting the use of BTX-A injections for this indication.

Clinical comparisons of botulinum neurotoxin formulations

BACKGROUND

The expanding uses of botulinum neurotoxin (BoNT) for a growing number of clinical indications, including cervical and other dystonias, adult and childhood spasticity, and hyperhidrosis, in conjunction with the emergence of new formulations of BoNT, prompt discussion of the differences in formulations, serotypes, and indications for different neurologic diseases.

REVIEW SUMMARY

This review will evaluate evidence from preclinical studies, prospective treatment studies, and direct comparative trials to discuss the differences among BoNTs and the clinical implications of using these different drugs. Data from these sources indicate that formulations of BoNT are distinct; even the same serotype formulations of BoNT serotype A have different molecular structures and sizes and therapeutic indices (reflected in different safety and efficacy profiles).

CONCLUSION

Taken together, these findings confirm that the different BoNT serotypes, including the different BoNTA formulations, are distinct therapeutic entities.

Botulinum neurotoxin — from laboratory to bedside

Botulinum neurotoxin (BoNT) has been used clinically since 1980, with an ever-increasing range of clinical applications. This has coincided with a period of massively expanded interest in the underlying biology of the neurotoxin. Tremendous advances have taken place in the scientific understanding of neurotoxin structure and function since the description of their endopeptidase activity in 1992. These developments have led to an increased understanding of the mechanisms underpinning the clinical use of the neurotoxins and also in the technologies available to support their clinical use. The expanding range of clinical applications, and use in increasing doses, has also generated challenges for the clinicians and manufacturers of BoNT preparations to ensure continuing efficacy and safety margins for these new clinical settings. To date the increased clinical use of BoNTs has occurred largely empirically, and not by application of the recent insights into neurotoxin structure and function. With the increased knowledge regarding the biology of the neurotoxins, however, there is the opportunity to select preferred forms of the toxin for particular clinical applications and even to consider engineering the neurotoxins to produce modified products more suited to specific clinical applications. These developments and opportunities that have arisen, particularly over the last decade, emphasise the increasing need to maintain an active two way dialogue between clinicians and basic scientists to ensure that the advances in the laboratory are translated into clinical benefit and that the clinical developments in use of neurotoxin are supported by the scientific research activity. This article is based upon presentations given in a workshop at the 5th International Conference on Basic and Therapeutic Aspects of Botulinum and Tetanus Toxin in Denver in June, 2005 seeking to address issues relating to the laboratory/clinic interface.

Surface Anatomy of the Lip Elevator Muscles for the Treatment of Gummy Smile Using Botulinum Toxin

Objective: To propose a safe and reproducible injection point for botulinum toxin-A (BTX-A) as a supplementary method for the treatment of gummy smile, as determined by assessment of the morphologic characteristics of three lip elevator muscles.

Materials and Methods: A total of 50 hemi-faces from 25 adult cadavers (male 13, female 12; ages, 47 to 88 years) were used in this study. Topographic relations and the directions of the lip elevator muscles (ie, levator labii superioris [LLS], levator labii superioris alaeque nasi [LLSAN], and zygomaticus minor [ZMi]), were investigated. Possible injection points were examined through the study of predetermined surface landmarks.

Results: The insertion of the LLS was covered partially or entirely by the LLSAN and the ZMi, and the three muscles converged on the area lateral to the ala. The mean angle between the facial midline and each muscle vector was 25.8 ± 4.8 degrees for the LLS, 55.7 ± 6.4 degrees for the ZMi, and −20.2 ± 3.2 degrees for the LLSAN; no significant differences were noted between male and female subjects or between left and right sides. The three vectors passed near a triangular region formed by three surface landmarks. The center of this triangle, named the “Yonsei point”, was suggested as an appropriate injection point for BTX-A. The clinical effectiveness of the injection point was demonstrated in selected cases with or without orthodontic treatment.

Conclusions: Under careful case selection, BTX-A may be an effective treatment alternative for patients with excessive gingival display caused by hyperactive lip elevator muscles.

Quantification of eccrine sweat glands with acetylcholine sweat-spot test and anatomical redistribution of sweating after T2-T3 thoracoscopic sympathicolysis

BACKGROUND

In this study, patients treated by thoracoscopic sympathicolysis for palmar hyperhidrosis were evaluated to determine the number and response of sweat glands to intradermal acetylcholine stimulus.

METHODS

A total of 30 patients were included in the study. Group A consisted of 10 patients with palmar hyperhidrosis who underwent thoracoscopic sympathicolysis in October 2005, and group B consisted of 20 patients who underwent surgery during the years 1999, 2000, and 2001. The study procedure involved applying iodine alcohol to the palm and then intradermally injecting 0.1 ml 1% acetylcholine. This activated the sweat glands, which were then photographed and counted. The study procedure was performed prospectively over different periods in group A and retrospectively in group B.

RESULTS

In group A, the mean number of glands activated 1, 3, 6, and 12 months after surgery were 41, 174.20, 522.8, and 747.2, respectively; this gradual increase was statistically significant over the first 6 months (p = 0.004) but not between months 6 and 12 (p = 0.255). The trend towards an increasing number of active glands occurred in both groups, with a mean of 1369.8 active glands in group B compared to 747.2 (p = 0.095) in group A after 12 months.

CONCLUSION

It is well-known that Cannon's law of denervation (1939) is not applicable to the sweat glands, that is, there is no hyperactivation following intradermal acetylcholine stimulation. However, some response, which increased over the first 6 months following surgery, was observed in our study. Nevertheless, this activation is subsequently self-limiting, resulting in no gland atrophy, and reinnervation occurs without patient awareness.