Polyradiculoneuritis after botulinum toxin therapy for cervical dystonia

A 40-year-old man with cervical dystonia developed an acute inflammatory demyelinating polyradiculoneuritis after botulinum toxin type A treatment. Some cases of idiopathic brachial plexopathy and polyradiculoneuritis have been reported to date. Although a causal relationship is not firmly established, the clinical temporal profile suggests a pathogenic relationship. In patients with cervical dystonia, further use of type A botulinum toxin should be considered contraindicated, and the use of another type of botulinum toxin should be taken into consideration.     

Evidence-based medicine in botulinum toxin therapy for cervical dystonia

Early controlled studies of botulinum toxin (BTX) in cervical dystonia were unblinded and indicated that BTX injections are more successful than medication. In this article, the use of botulinum toxin (BTX) in cervical dystonia is reviewed according to evidence-based medicine. To document the efficacy of BTX, there have been a number of prospective, placebo-controlled studies of the use of BTX in cervical dystonia. Most were double-blind, some included videotapes to provide blinded objective assessments. The more recent studies of BTX in cervical dystonia focused on particular issues such as utility of EMG guidance, comparison to anti-cholinergic treatment, BTX serotype B in BTX type A resistant and non-resistant patients and different dosages. Despite the wealth of data generated with prospective placebo-controlled studies on the effectiveness of BTX in cervical dystonia, there is uncertainty on which outcome measures to use to express the efficacy of treatments for cervical dystonia. Disease specific instruments to measure quality of life in cervical dystonia have not been used so far. Data on the use of BTX for cervical dystonia have long been restricted to small series of patients reflecting exclusively the experience of individual specialized centers.     

Evidence-based medicine in botulinum toxin therapy for cervical dystonia

Early controlled studies of botulinum toxin (BTX) in cervical dystonia were unblinded and indicated that BTX injections are more successful than medication. In this article, the use of botulinum toxin (BTX) in cervical dystonia is reviewed according to evidence-based medicine. To document the efficacy of BTX, there have been a number of prospective, placebo-controlled studies of the use of BTX in cervical dystonia. Most were double-blind, some included videotapes to provide blinded objective assessments. The more recent studies of BTX in cervical dystonia focused on particular issues such as utility of EMG guidance, comparison to anticholinergic treatment, BTX serotype B in BTX type A resistant and non-resistant patients and different dosages. Despite the wealth of data generated with prospective placebo-controlled studies on the effectiveness of BTX in cervical dystonia, there is uncertainty on which outcome measures to use to express the efficacy of treatments for cervical dystonia. Disease specific instruments to measure quality of life in cervical dystonia have not been used so far. Data on the use of BTX for cervical dystonia have long been restricted to small series of patients reflecting exclusively the experience of individual specialized centers.

     

Focal dystonia: The role of botulinum toxin

Botulinum toxin (BTX) has been found to be effective in a wide range of focal dystonias. Debate surrounds the selection of injection sites. In general, localization is satisfactory by clinical examination, but poor response, requiring localization of deep muscles, may necessitate use of electromyography for localization. Delineation of optimal doses of BTX is a work in progress; as studies have tended to show efficacy at lower doses than used in the past, the trend is to use lower doses. This is important, because development of antibodies to BTX, the main reason for secondary resistance to this treatment, is more frequent with larger doses and shorter inter-injection intervals. Although the mechanism of denervation of the neuromuscular injunction by BTX is relatively well understood, secondary changes at the level of the basal ganglia, thalamus, and cortex, and their role in response to BTX, need further exploration.     

Electromyographic evaluation of cervical dystonia for planning of botulinum toxin therapy

The success of botulinum toxin (BT) injections for treatment of cervical dystonia depends on precise identification of dystonic muscles and on quantification of their dystonic involvement. Conventionally, this is attempted by clinical examination analysing the dystonic head position. In this presentation, a more systematic approach is sought by using an electromyography (EMG)-based evaluation procedure. In 10 consecutive patients with cervical dystonia not previously exposed to BT clinical examination, analysing the dystonic head position was performed to classify patients into four groups with similar dystonic head positions. Additionally, a 2-channel concentric needle EMG was used to measure the amplitudes of dystonic and maximal voluntary activities in sternocleidomastoid (SCM), splenius capitis (SC) and trapezius/semispinalis capitis (T/SS) muscles bilaterally. The ratio between both amplitudes, the dystonia ratio, was used to quantify dystonic muscle involvement. In all patients dystonia ratios could be calculated. In patients with similar head positions, EMG evaluation revealed different qualitative and quantitative dystonic involvement patterns. In six patients, there were discrepancies in identification of dystonic muscles between clinical examination and EMG evaluation. EMG evaluation excluded dystonic involvement in five patients. All excluded muscles were SCM. In one of these patients, additional T/SS involvement was detected by EMG evaluation. In one patient, SC involvement was revealed by EMG evaluation. All dystonic muscle involvement detected by EMG evaluation represented genuine dystonic muscle coactivation rather than compensatory muscle activity. The EMG evaluation presented allows quantitative and qualitative identification of dystonic muscle involvement which cannot be achieved by clinical examination. Both pieces of information may be helpful for optimization of BT therapy.     

Botulinum toxin in blepharospasm and oromandibular dystonia: comparing different botulinum toxin preparations

Amongst all regions of the body, the craniocervical region is the one most frequently affected by dystonia. Whilst blepharospasm – involuntary bilateral eye closure – is produced by spasmodic contractions of the orbicularis oculi muscles, oromandibular dystonia may cause jaw closure with trismus and bruxism, or involuntary jaw opening or deviation, interfering with speaking and chewing. Both forms of dystonia can be effectively treated with botulinum toxin injection. This article summarizes injection techniques in both forms of dystonia and compares doses, potency and efficacy of different commercially available toxins, including Botox®, Dysport®, Xeomin® and Myobloc®/NeuroBloc®.     

A survey about the accessibility to botulinum toxin therapy for dystonia]

We investigated the accessibility of the therapy with botulinum toxin for blepharospasm or cervical dystonia in Japan. Based on the administration sheet for Botox sent to the Japan Branch of Allergan Co. Ltd. (Tokyo, Japan), the survey was performed about how many institutions treated 3 or more patients with botulinum toxin in each of February, 2003, and February, 2005, for each disease entity. Among 369 secondary medical zones covering all the areas of Japan, 73 zones had 103 institutions that met our criteria for blepharospasm in 2003, and the number slightly increased to 77 zones and 109 institutions in 2005. For cervical dystonia, 25 zones had 32 institutions in 2003, and the number increased to 36 zones and 48 institutions in 2005. Although medical zones with larger population tended to have more institutions, there was great inequality in the accessibility of patients among medical zones. Besides, the number of institutions was thought to be quite insufficient especially for cervical dystonia in most areas of Japan. Larger number of institutions in any region of Japan should be preferably able to treat focal dystonia with botulinum toxin in order to improve patients' accessibility, because this safe and effective therapy can be now regarded as the first line for both blepharospasm and cervical dystonia.     

Treatment of cervical dystonia hand spasms and laryngeal dystonia with botulinum toxin

Summary One hundred and twenty-six patients with different forms of focal dystonia (89 with cervical dystonia, 12 with hand cramps and 25 with laryngeal dystonia) were treated with localised injections of botulinum toxin. Mean doses per muscle were 200 mouse units (m.u.) for treating cervical dystonia, 40–120 m.u. for forearm muscles in writers' cramp and 3.7 m. u. for the thyroarytenoid muscle in laryngeal dystonia. Responder rates have been above 80% in all patient groups and beneficial effects could be reproduced over follow-up periods of up to 4 years. The commonest side-effects were dysphagia after treatment of spasmodic torticollis, weakness of neighbouring muscles after injections for hand cramps and breathiness and hypophonia following laryngeal injections. All these were transient and generally well tolerated. It is concluded that botulinum toxin injections are a safe and effective treatment in all three types of focal dystonia.     

Personalized botulinum toxin type A therapy for cervical dystonia based on kinematic guidance

Background

Botulinum toxin type A (BoNT-A) injections is the accepted first-line therapy for cervical dystonia (CD), however, numerous patients discontinue treatment early due to perceived sub-optimal relief. To improve BoNT-A therapy for CD, proper assessment of neck motion and selection of relevant muscles and dosing must be met. Kinematic technology may improve treatment outcomes by guiding physicians to better tailor muscle selection and BoNT-A dosing for CD therapy.

Methods

28 CD participants were placed into either group: expert injector determined injection patterns by visual assessment (“vb”) versus injection patterns based on kinematics interpreted by an expert injector (“kb”). Injections occurred at weeks 0, 16 and 32 with follow-ups at weeks 6, 22 and 38. Kinematics utilized four sensors to capture the severity of multiaxial, static neck posturing (e.g., torticollis) and dynamic, spasmodic/tremor movements while participants were seated. Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) score changes were evaluated over 38 weeks.

Results

For the “kb” participants, there was a significant 28.8% (? 11.25 points) reduction in TWSTRS total score at week 6, as well as significant reduction in severity and disability TWSTRS sub-scores (parts I and II) with maintained improvement at subsequent visits. As for the “vb” participants had a significant reduction in total TWSTRS score by 28.5% (? 9.84 points) after week 22. Disability score for the “vb” group trended towards improvement over 38 weeks.

Conclusion

Clinical judgement guided by kinematic analysis of CD biomechanics can result in faster optimal muscle selections and minimize use of higher BoNT-A doses as compared to visual determination, thereby achieving comparable and potentially better treatment outcomes.

     

Secondary dystonia in a botulinum toxin clinic: clinical characteristics, neuroanatomical substrate and comparison with idiopathic dystonia

The analysis of patients with secondary dystonia has been valuable to explore the anatomical, pharmacological and physiological bases of this disorder. The goal of this study is to compare the clinical characteristics of patients with primary and secondary dystonia and analyze the neuroanatomical bases of a subgroup of patients with lesion-induced dystonia. We identified patients evaluated in our Botulinum Toxin Clinic from 1/2000 to 7/2009 with an ICD code for "dystonia". Medical records of all subjects were reviewed, recording demographic, clinical, therapeutic and neuroimaging data. A total of 230 patients were included in the study. Idiopathic/primary dystonia was diagnosed in 162 and secondary dystonia in 58, while in 10 the etiology was uncertain. We found a female predominance (2.4:1 and 1.9:1 for primary and secondary dystonia, respectively). The cervical region was most commonly affected in primary dystonia and the limbs in secondary cases. The age at presentation was higher in primary (54.4?±?14.1) than secondary (49?±?17.9) dystonia. Among patients with secondary dystonia, a focal lesion was the presumed etiology in 32, with localizing diagnostic studies available in 16. The most common lesions were strokes involving the corticospinal pathway. All of those patients exhibited limb dystonia, except one with cervical dystonia following a thalamic infarct. In conclusion, primary and secondary dystonias are more prevalent in women, suggesting a sex-related predisposition to the development of this movement disorder. Lesion-induced dystonia most frequently involves the limbs and is caused by lesions in the cerebral cortex and subcortical white matter.     

Self-reported benefit and weakness after botulinum toxin in dystonia

With this retrospective, single center, chart review study, we investigate the self-reported benefit and weakness after botulinum toxin injections in three different types of dystonia: focal hand dystonia (FHD), blepharospasm and cervical dystonia. We found that the benefit lasts significantly longer in FHD compared to the other two groups.     

Treatment of upper limb dystonia with botulinum toxin

The use of botulinum toxin A (BTX A) in upper limb dystonia is gaining increasing acceptance and it has recently been suggested that it be considered as first line treatment.(1) We have reviewed our experience since 1991 of treating 20 cases of upper limb dystonia. 14 patients had task-specific dystonias (6 simple writer's cramp, 5 dystonic writer's cramp, 3 musician's cramp) and 6 had secondary focal or segmental dystonias (4 with early cortico-basal degeneration). All patients had electromyography to both determine and guide muscle selection. Pre- and post-treatment video as well as questionnaires formed the basis for outcome assessment. Botulinum toxin therapy was clearly beneficial in about two-thirds of those with primary upper limb dystonia, a condition affecting young adults (mean onset 32.9 years). In contrast, BTX A was far less effective in secondary upper limb dystonias which occurred in the elderly (mean onset 71.7 years). Optimal treatment strategies are discussed. In conclusion, botulinum toxin is an effective form of treatment for primary upper limb dystonia; its role in late onset secondary dystonia is mainly palliative.     

Determinants and status of quality of life after long-term botulinum toxin therapy for cervical dystonia

The aim of this study was to assess health-related quality of life (HRQoL), using the Short Form Health Survey-36 (SF-36), in 70 cervical dystonia (CD) patients after long-term botulinum toxin (BTX) treatment (median 5.5 years), and to identify factors determining reduced HRQoL. We used combined patient-and physician-based measures to assess both CD severity [Toronto Western Spasmodic Torticollis Rating Scale, (TWSTRS)] and effect of long-term BTX treatment, and the Hospital Anxiety and Depression Scale (HAD) and General Health Questionnaire-30 to assess psychological distress. Mean SF-36 domain scores of the CD patients were reduced by <1 SD compared with age- and gender-matched population samples. High TWSTRS total scores and high HAD-depression (HAD-D) scores were the main factors associated with reduced scores in the physical and mental SF-36 domains, respectively. Patients evaluated to have a 'good effect' of long-term BTX treatment ( n  = 47), had significantly lower median TWSTRS total score, and a 3× lower frequency of high HAD-D scores, than those evaluated to an 'unsatisfactory effect' ( n  = 23). In conclusion, most CD patients enjoy a good HRQoL after long-term BTX therapy. Reduced HRQoL was associated with more severe disease and/or depressive symptoms.     

Electromyographic guidance of botulinum toxin treatment in cervical dystonia

We report the results of electromyographic (EMG) guidance in the treatment of cervical dystonia with botulinum toxin. Eight-four patients received a total of 225 injection sessions. Overall there was moderate objective improvement in 78.7%. The mean dose of toxin was 269 +/- 39 mouse lethal units and the mean duration of maximum effect was 107 +/- 49 days. Complications included excessive neck weakness in 16.0% and dysphagia in 11.1% of the injection sessions. We conclude that EMG guidance is a safe and effective method of administering botulinum toxin in the treatment of cervical dystonia.     

A型肉毒毒素治疗口下颌肌张力障碍

目的观察A型肉毒毒素治疗口下颌肌张力障碍(OMD)患者的临床效果。方法对19例口下颌肌张力障碍患者进行临床分析,依据患者临床特点,将A型肉毒毒素注射到患者一侧或双侧咀嚼肌、颞肌及翼外肌,并根据肌肉收缩力量大小、肌肉体积及患者体重调整剂量。结果 68.4%的患者功能改善评分≥3分,疗效平均维持8～12周(有效范围2～28周)。4例患者注射后有轻度咀嚼无力,2～3周恢复。1例混合型患者注射后出现轻度鼻音,持续13天后症状消失。所有患者未出现其它严重副作用。结论 A型肉毒毒素对于口下颌肌张力障碍的治疗是有效、安全的。熟悉本病的临床特点及分型,选择正确的靶肌肉及注射适宜剂量的肉毒毒素是治疗本病的关键。     

Polyradiculoneuritis following botulinum toxin therapy

Summary The development of Guillain-Barré syndrome is reported in a patient, who had previously received botulinum toxin type A injections into both orbicularis oculi muscles to treat idiopathic blepharospasm. The possibility of a causal relationship is discussed with consideration of the literature on adverse effects of vaccinations and of Clostridium botulinum and its toxin.