肌电图引导局部肌肉注射A型肉毒毒素治疗痉挛性斜颈的疗效观察

目的 观察肌电图(EMG)引导局部肌肉注射A型肉毒毒素(BTX-A)治疗痉挛性斜颈(CD)的疗效.方法 应用EMG检查19例CD患者头颈部152块肌肉,针对放松状态下出现的多频群放电位的114块靶肌肉进行BTX-A局部肌肉注射;治疗前后分别采用Tsui量表对病情和疗效进行评估;随访观察疗效持续时间以及不良反应.结果 治疗后EMG发现靶肌肉5块;根据Tsui量表评分,治疗后总有效率第1周为47.3%,第2周为78.9%,第3、4周均为94.7%;随访显示疗效平均保持10个月;不良反应轻微,均在4周内自行缓解.结论 EMG引导局部肌肉注射BTX-A治疗CD安全有效.     

肌电图引导下A型肉毒毒素治疗不同类型痉挛性斜颈的临床研究

目的：探讨A型肉毒毒素（BTX-A）局部注射治疗不同类型原发性痉挛性斜颈的疗效。方法：在肌电图引导下,对24例痉挛性斜颈患者行BTX-A局部肌肉注射,按其临床类型分组比较疗效及不良反应。结果：全部患者治疗后Tsui量表评分均明显下降,混合型改善程度更明显。所有患者均未见严重不良反应。结论：肌电图引导下BTX-A治疗不同类型痉挛性斜颈均有效,且安全。     

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.     

The finding and evaluation of EMG-guided BOTOX injection in cervical dystonia

In this prospective study we report the results of EMG-guided BOTOX injections in a total of 15 cervical dystonia (CD) patients. Pre-treatment and post-treatment evaluations included physical examination results, Tsui ratings, and video recording. The dosage of BOTOX injection was determined by the EMG pattern, type of CD, and the degree of muscle hypertrophy. Seven patients underwent injections with and without EMG, and eight patients underwent injections with EMG-guidance only. The results showed that among the patients who underwent EMG-guided BOTOX injection there are: (1) fewer BOTOX-related side effects due to injection of the adequate dose of BOTOX to the accurate site of hyperactive muscles, (2) greater clinical improvement due to confirmation of hyperactivity in muscles in each type of cervical dystonia, (3) a better ability to reduce the amount of oral medication for treatment of muscle pain and spasms. We suggest that the use of EMG-guided BOTOX injections be considered for those CD patients with retrocollis, those who have had a sub-optimal treatment response to non EMG-guided BOTOX injections, and those with increased concern of side effects or a concomitant goal of reducing oral medications.     

The effect of two different rehabilitation treatments in cervical dystonia: preliminary results in four patients

The most widespread approach to rehabilitation of cervical dystonia is electromyographic (EMG) biofeedback. However, consensus is lacking regarding the true effectiveness of this technique. The aim of this study was to evaluate how cervical dystonia was influenced by two rehabilitative treatments, namely a standard biofeedback program and a novel physiotherapy program consisting of postural reeducation exercises and passive elongation of myofascial cervical structures. Both programs were consecutively administered to 4 patients with cervical dystonia. The study design was a behavioral analysis of single cases. The main outcome measures were a head realignment test, a disability questionnaire and a pain visual analogue scale (VAS). Each patient's performance was evaluated before the study and after the first and second program. Furthermore, the disability questionnaire and the pain VAS were administered 3, 6, and 9 months after the end of the treatments. The physiotherapy program showed therapeutic effects comparable to those of EMG biofeedback. Reductions of disability and of pain were still present 3-9 months after the end of the treatments. These preliminary results suggest that the physiotherapy program proposed in the present study may be a promising method for rehabilitation of cervical dystonia.     

Cervical dystonia: Improved treatment response to botulinum toxin after referral to a tertiary centre and the use of polymyography

RationaleCervical dystonia is the most common form of (primary) dystonia. The first line of treatment for cervical dystonia is intramuscular injections with botulinum toxin. To optimise the response to botulinum toxin proper muscles selection is required. Pre-treatment polymyographic EMG in addition to clinical evaluation is hypothesised to be a good tool to improve muscle selection and treatment outcome.ObjectiveTo determine the efficacy of botulinum toxin treatment after adjacent polymyographic EMG in cervical dystonia patients referred to our tertiary referral centre with an unsatisfactory response to botulinum toxin treatment elsewhere.MethodsWe performed a retrospective analysis of 40 consecutive second opinion cervical dystonia patients. Standard polymyographic EMG was performed before treatment. We retrieved the Tsui scores and subjective evaluations from the first visit, after 12 weeks and after one year of treatment. In addition, we assessed the final outcome of treatment in our centre based on the records and asked the patients for their personal opinion about the effect of referral to our centre on their treatment response.ResultsAfter one year of treatment there was a significant improvement on both the Tsui scores (p < 0.01) and the subjective treatment evaluation (p < 0.001.) On their last visit 60% of the patients still continued treatment with a reasonable to good response.ConclusionA substantial amount of CD patients with an unsatisfactory response to botulinum toxin improved after polymyography and subsequent treatment with botulinum toxin in a tertiary referral centre.     

Efficacy and safety of a standardised 500 unit dose of Dysport (clostridium botulinum toxin type A haemaglutinin complex) in a heterogeneous cervical dystonia population: results of a prospective,multicentre, randomised,double-blind,placebo-controlled,parallel group study

Results from a dose-ranging study in a selected group of de novo patients with rotational cervical dystonia (CD) suggest that 500 units of Dysport (Clostridium botulinum toxin type A haemaglutinin complex) is the optimal starting dose. The present study aimed to confirm the efficacy and safety profile of this dose in a population of CD patients more representative of those seen in a typical dystonia clinic. A total of 68 patients with moderate to severe CD (Tsui score ≥ 9) were randomly assigned to receive placebo or Dysport 500 units. Treatment was administered according to the clinical pattern of head deviation, using a standardised injection protocol. A total of 21 patients (11 Dysport, 10 placebo) had not previously received botulinum toxin type A (BtxA) injections, and 47 patients (24 Dysport, 23 placebo) had received BtxA more than 12 weeks previously. Assessments were performed at baseline and weeks 4, 8 and 16. Patients defined as non-responders at week 4 were re-treated in an open phase with 500 units of Dysport at week 6, and were followed up at week 10. Significant between-group differences in Tsui scores were present at weeks 4 (p=0.001) and 8 (p=0.002). Similarly, there were significant between-group differences (p < 0.001) in patient and investigator assessments of response in favour of Dysport at weeks 4 and 8. Also, more Dysport (49 %) than placebo (33 %) patients were pain-free at week 4 (p=0.02). Overall, 30/35 (86 %) Dysport patients and 14/33 (42 %) placebo patients were classified as responders at week 4. Adverse events were reported by 15/35 Dysport patients and 9/33 placebo patients. Open phase treatment produced improvements in Tsui (p < 0.001) and pain scores (p=0.011), and 23/24 patients were classified as responders. Although individual dose titration and muscle selection is desirable, this study demonstrated that a dose of 500 units of Dysport injected into clinically identified neck muscles without electromyographic guidance is safe and effective in the treatment of patients with the major clinical types of cervical dystonia. Received: 3 October 2000, Received in revised form: 20 March 2001, Accepted: 2 May 2001     

Respective potencies of Botox and Dysport: a double blind, randomised, crossover study in cervical dystonia

OBJECTIVES: Botulinum toxin type A is a potent neuromuscular paralyzing agent used in various disorders including cervical dystonia. Two preparations of botulinum toxin are now commercially available ( Dysport and Botox), but much controversy remains about their respective potencies. The aim of the study was to compare the efficacy of Botox with two different ratios of Dysport. METHODS: A double blind, randomised, three period cross over study involving 54 patients with cervical dystonia was performed. The patients received the following treatments in a randomised order: Botox at the usually effective dose, Dysport at a dose of 1:3 (conversion factor of 3 between Botox and Dysport units-that is, one Botox unit=three Dysport units) and at a dose of 1:4 (conversion factor of four). The improvement of the Tsui (primary outcome criteria) and of the TWSTRS pain scales between baseline and a control visit 1 month after each of the three injections, as well as the incidence of adverse events, were assessed. RESULTS: Comparison of the Tsui scores and of the TWSTRS pain scores showed a better effect on impairment and pain with Dysport 1:3 (p=0.02 and 0.04, respectively) and 1:4 (p=0.01 and 0.02, respectively) than with Botox. The number of adverse events was higher with both Dysport treatments. The most frequent adverse event was dysphagia, found in 3%, 15.6%, and 17.3% (Botox, Dysport 1:3 and 1:4, respectively) of the patients. No adverse event required withdrawal of therapy or specific management. CONCLUSIONS: Dysport 1:3 (and Dysport 1:4 to a greater extent) is more efficient than Botox for both impairment and pain in cervical dystonia although with a somewhat higher incidence of minor adverse effects. This strongly suggests that the most appropriate conversion factor between Botox and Dysport units is less than 3 in cervical dystonia.     

Chronic high-frequency globus pallidus internus stimulation in different types of dystonia: a clinical, video, and MRI report of six patients presenting with segmental, cervical, and generalized dystonia.

The results of deep brain stimulation (DBS) of the globus pallidus internus (Gpi) in six patients with generalized, focal, and segmental dystonia are presented. Pre- and postoperative assessments are given for one patient with generalized inherited dystonia and for five patients with idiopathic segmental or cervical dystonia. Clinical symptoms were evaluated before and 3-12 months after surgery using the Burke-Fahn-Marsden (BFM) dystonia rating scale for primary torsion dystonia and the Tsui scale for cervical dystonia. The Short-Form Health Survey (SF-36) was completed by each patient to document preoperative and postoperative health status. Also, neurological status was documented by video before and during chronic stimulation. Magnetic resonance imaging studies were performed to show the anatomical localization of the electrode leads. Five patients showed a progressive improvement within 7 days. One patient with cervical dystonia and Meige's syndrome showed no improvement for 3 months, but beneficial effects were observed after 12 months. On average, the BFM movement scale scores decreased by 72.5% and Tsui scale scores by 63%. SF-36 showed an improvement in health status by an average of 36% according to eight different health categories. We conclude that chronic high-frequency Gpi stimulation in different types of dystonia is a very effective and safe treatment.     

Utility of an EMG mapping study in treating cervical dystonia

Intramuscular injections of botulinum toxin are the cornerstone of treatment for cervical dystonia. Controversy exists regarding the necessity for EMG-guided injections. We compared the clinical examination of four movement disorder specialists to an electromyographic (EMG) mapping study. Clinical predictions of individual muscle involvement were only 59% sensitive and 75% specific. Muscle hypertrophy, shoulder elevation, and dominant head vector did not bolster clinical accuracy. An EMG mapping study facilitates identification of dystonic muscles in cervical dystonia, which may enhance botulinum toxin therapy.     

Long-Term Abobotulinumtoxin A Treatment of Cervical Dystonia

Botulinum toxin is considered as first-line therapy for cervical dystonia, but few papers have addressed these issues in the long term. Aim of this study was to investigate the long-term efficacy and safety of abobotulinumtoxin A (A/Abo) in patients with primary cervical dystonia. Consecutive patients who received at least six injections with A/Abo were included. Safety was assessed on patients’ self-reports. Efficacy was assessed by recording the total duration of benefit, duration of maximum efficacy, disease severity measured by means of the Tsui score, and pain intensity evaluated by means of the visual analog scale (VAS). Thirty-nine patients with PCD were included. The mean dose injected was 701.5 ± 280.6 U. The mean duration of the clinical improvement was 93.0 ± 30.7 days, while the mean duration of the maximum clinical improvement was 77.1 ± 27.1 days. The mean VAS before and 4 weeks after injection was 4.4 ± 1.8 and 1.8 ± 1.6, respectively. The mean Tsui score before and 4 weeks after treatment was 5.7 ± 1.8 and 3.5 ± 1.5, respectively. Doses of A/Abo and duration of the maximum clinical improvement significantly increased over time, while the Tsui score and VAS displayed a tendency to decrease along time. Side effects occurred in 19.6% of all the treatments but were severe in only four injections. The results of our study confirm the effectiveness and safety profile of A/Abo for the long-term treatment of primary cervical dystonia.     

Long-term botulinum toxin treatment of cervical dystonia--EMG changes in injected and noninjected muscles.

OBJECTIVE: To evaluate changes in quantitative EMG of injected and noninjected sternocleidomastoid muscles following long-term unilateral botulinum toxin treatment of cervical dystonia. METHODS: We investigated 27 patients with cervical dystonia, who received repeated unilateral botulinum toxin injections of the sternocleidomastoid muscle, with quantitative EMG at rest and at maximal voluntary contraction. The patients had on the average 7.1 botulinum toxin treatments and the follow-up period was on the average 31 months (SD 16). RESULTS: After the first treatment, the injected sternocleidomastoid muscles showed a significant decrease in turns/s (mean 45%) and amplitude (mean 52%) at rest, and in amplitude at maximal flexion (mean 24%) and rotation (mean 39%). Except for a reduction in turns/s at rotation (mean 19%) no further reductions in EMG parameters were seen after long-term treatment. The contralateral noninjected sternocleidomastoid muscles showed no significant change in EMG activity after the first BT treatment, but after long-term treatment a significant reduction in turns/s and amplitude at both maximal flexion (turns: mean 28%; amplitude: mean 25%) and rotation (turns/s: mean 32%; amplitude: mean 25%) were seen as compared to pretreatment values. CONCLUSION: The results indicate that there seems to be no cumulative chemodenervation by repeated botulinum toxin injections of sternocleidomastoid muscles measured by quantitative EMG. Contralateral noninjected sternocleidomastoid muscles however, seem to be affected following long-term treatment. The mechanism behind this finding is unknown.     

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.     

Polymyography combined with time-locked video recording (video EMG) for presurgical assessment of patients with cervical dystonia

We assessed 26 patients with cervical dystonia, in whom botulinum toxin (BT) injections had failed, before selective peripheral denervation. We decided to base the decision which muscle should be denervated on both clinical information and EMG data and focussed on the following features: activity at onset or during 'dystonic spasms' (according to the concept of the 'leading' dystonic muscle), paradoxical activity during voluntary head movements causing restriction of head movements opposite the side of head turn or tilt and activity when symptoms deteriorated during walking. To identify these muscles we developed a new recording system that integrates simultaneous video-taping and polymyography (video EMG) by means of a digital counter, driven by the recording software (resolution 0.1 s), that was fixed in view of the video camera. This system time-locked clinical signs with relevant EMG activity thus allowing demonstration of the above features. These were found in 68% of dystonic muscles with each of them being present in approximately 40%. Video EMG allows an integrated approach to identify overactive neck muscles in patients with cervical dystonia taking into account both relevant clinical findings and EMG data.     

Accuracy of muscle localization without EMG: implications for treatment of limb dystonia

Although botulinum toxin is an effective treatment for focal dystonia, the importance of electromyography (EMG) in identifying muscles and guiding injections is unclear. The authors examined the accuracy of muscle localization in 38 muscles in patients with focal hand dystonia without EMG guidance. Only 37% of needle placement attempts reached the target muscles or muscle fascicles. This study demonstrates that EMG guidance is needed for correct localization of desired muscles.     

Selective peripheral denervation: comparison with pallidal stimulation and literature review

Patients with cervical dystonia who are non-responders to Botulinum toxin qualify for surgery. Selective peripheral denervation (Bertrand’s procedure, SPD) and deep brain stimulation of the globus pallidus (GPi-DBS) are available surgical options. Although peripheral denervation has potential advantages over DBS, the latter is nowadays more commonly performed. We describe the long-term outcome of selective peripheral denervation as compared with GPi-DBS, along with the findings of literature review. Twenty patients with selective peripheral denervation and 15 with GPi-DBS were included. Tsui scale, a visual analogue scale, and the global outcome score of the Toronto Western Spasmodic Torticollis Rating Scale were used to define a “combined global surgical outcome”. The “combined global surgical outcome” for patients with selective peripheral denervation or pallidal stimulation was respectively “bad” for 65 and 13.3 %, “fair-to-good” for 30 and 26.7 %, and “marked” improvement for 5 and 60 % (p < 0.001). Improvement on visual analogue scale (p < 0.002), global outcome score (p < 0.002), and Tsui score (p < 0.000) was larger for the pallidal stimulation group. Seventy-five percent of patients with selective peripheral denervation and 60 % of patients with pallidal stimulation reported side effects. Seven patients with selective peripheral denervation successively underwent GPi-DBS, with a further significant improvement in the Tsui score (?48.6 ± 17.4 %). GPi-DBS is to be preferred to selective peripheral denervation for the treatment of cervical dystonia because it produces larger benefit, even if it can have more potentially severe complications. GPi-DBS is also a valid alternative in case of failure of SPD.     

Descending control of muscles in patients with cervical dystonia.

It was reported recently that specific features in the frequency analysis of electromyographic (EMG) activity in the sternocleidomastoid (SCM) and splenius (SPL) muscles were able to distinguish between rotational idiopathic cervical dystonia (CD) and voluntary torticollis in individual subjects. Those with CD showed an abnormal drive to muscles at 5 to 7 Hz and an absence of the normal 10 to 12 Hz peak in the autospectrum of SPL. We sought to determine whether the same abnormalities in the frequency domain are found in complex CD, in which the head is displaced in more than two planes. EMG activity was recorded in the SCM, SPL, trapezius, and levator scapulae muscles bilaterally in 10 patients with complex CD. Frequency analysis of EMG was compared with conventional clinical and polymyographic assessment. The autospectrum of SPL during free dystonic contraction showed an absence of a significant peak at 10 to 12 Hz in 8 of the 10 patients. The presence of a 5 to 7 Hz frequency drive showed a significant association with muscle pairs determined as dystonic by means of polymyography (P < 0.005). The neck posture predicted blindly, based on the low-frequency drive, correlated significantly with the clinical assessment of posture (P < 0.01). Conventional assessment and the results of frequency analysis correlated, suggesting that a low-frequency drive to neck muscle may be a general feature of simple rotational and more complex cervical dystonia. The pattern of coherence between the EMG in different neck muscles may provide a means of identifying leading dystonic muscles, especially in patients with complex cervical dystonia.     

Riluzole therapy in cervical dystonia.

We conducted a 6-week open-label pilot study with blinded video rating of riluzole (50 mg twice a day) in six patients with cervical dystonia (CD) refractory to botulinum toxin A and oral pharmacological treatment. The Tsui rating scale served as primary efficacy measure and improved significantly under riluzole (P = 0.002). In three of six patients, the Tsui score improved by more than 30% with a greater 50% reduction in the head tremor/jerk subscore of the Tsui scale. These data suggest that riluzole may be helpful in a subgroup of patients with disabling CD refractory to other therapies.     

A double blind, randomised, parallel group study to investigate the dose equivalence of Dysport® and Botox® in the treatment of cervical dystonia

OBJECTIVE—This study was designed toestablish whether a ratio of three units of Dysport^® isequivalent to one unit of Botox^® for the treatment ofcervical dystonia.
METHODS—Patients with predominantly rotationalcervical dystonia, and a minimum of four previous Botox treatments,were randomised to receive either the clinically indicated dose ofBotox or three times that dose in Dysport units. Study botulinum toxinwas administered in a double blind fashion, to one or more clinicallyindicated muscles, at one or more sites per muscle. Patients returnedfor assessment two, four, eight, and 12 weeks after treatment.
RESULTS—A total of 73 patients (Dysport, 38;Botox, 35) were entered. The Dysport group received a mean (SD) dose of477 (131) (range 240-720) Dysport units, and the Botox group receiveda mean (SD) dose of 152 (45) (range 70-240) Botox units. The mean(SEM) post-treatment Tsui scores for the Dysport group (4.8 (0.3)) andthe Botox group (5.0 (0.3)) were not statistically different (p=0.66).The study had 91% power to detect a clinically significant differenceof two points. Both groups showed substantial improvement in Tsui scoreby week 2 (mean (SD); Dysport, 46 (28)%; Botox, 37 (28)%), with apeak effect at week 4 (mean (SD); Dysport, 49 (29)%; Botox, 44 (28)%). A similar response profile was seen for other assessments ofefficacy. The duration of effect, assessed by time to retreatment, wasalso similar (mean (SD); Dysport, 83.9 (13.6) days; Botox, 80.7 (14.4)days; p=0.85). During the study 22 of 38 (58%) Dysport patientsreported 39 adverse events, and 24 of 35 (69%) Botox patients reported56 adverse events (p=0.35). A global assessment of efficacy and safetyconsidered that 29 of 38 (76%) Dysport patients and 23 of 35 (66%)Botox patients were treatment successes (p=0.32).
CONCLUSION—Patients with predominantly rotationalcervical dystonia treated with the clinically indicated dose of Botoxor three times that dose in Dysport units show similar improvements anddo not have significantly different safety profiles.

     

Fluoroscopic, EMG-guided injection of botulinum toxin into the longus colli for the treatment of anterocollis

BackgroundAnterocollis is a form of cervical dystonia characterized by forward neck flexion. While botulinum toxin is the treatment of choice for cervical dystonia, patients with anterocollis, who receive injections into the sternocleidomastoid and anterior scalene muscles, represent a disproportionate number of treatment failures. Deep cervical muscles such as the longus colli likely play an important role in neck flexion but are not routinely injected.ObjectiveTo describe a technique for longus colli injection in cases of anterocollis and to report the clinical outcomes of 10 such injections of botulinum toxin.MethodsThree patients were referred for evaluation and treatment of anterocollis. All had previous treatment failures with sternocleidomastoid/anterior scalene injections or no activity noted on needle EMG investigation of these muscles. All patients received injections of botulinum toxin into the longus colli under fluoroscopic and EMG guidance.ResultsAll patients experienced symptomatic improvement (eight of 10 injections). Two patients reported mild dysphagia without serious complications after dose increases in botulinum toxin.ConclusionsIncomplete muscle selection may be one cause of treatment failures in anterocollis. Deep cervical flexors such as the longus colli represent an under-recognized potential target for symptomatic treatment of anterocollis.