Botulinum toxin versus trihexyphenidyl in cervical dystonia: a prospective, randomized, double-blind controlled trial. Botulinum toxin type B: a double-blind, placebo-controlled, safety and efficacy study in cervical dystonia. Quantitative EMG in botulinum toxin treatment of cervical dystonia. A double-blind, placebo-controlled study. Double-blind, placebo-controlled study of botulinum toxin injections in the treatment of cervical dystonia. 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. Safety and efficacy of NeuroBloc (botulinum toxin type B) in type A-resistant cervical dystonia. Safety and efficacy of NeuroBloc (botulinum toxin type B) in type A-responsive cervical dystonia. Efficacy and impact of botulinum toxin A on quality of life in patients with neurogenic detrusor overactivity: a randomised, placebo-controlled, double-blind study. Botulinum toxin A in the hemiplegic upper limb: a double-blind trial.
Botulinum toxin type A (BTA) is replacing trihexyphenidyl as the treatment of choice for idiopathic cervical dystonia (ICD), but there has never been a direct comparative study.
                This trial compares the effectiveness of BTA with that of trihexyphenidyl in a prospective, randomized, double-blind design. Sixty-six consecutive patients with ICD were randomized to treatment with trihexyphenidyl tablets plus placebo injection or placebo tablets plus BTA injections. Tablets were administered daily according to a fixed schedule. Dysport or saline was injected under EMG guidance at study entry and again after 8 weeks. Patients were assessed for efficacy at baseline and after 12 weeks by different clinical rating scales.
                Sixty-four patients completed the study, 32 in each group. Mean dose of BTA was 292 mouse units (first session) and 262 mouse units (second session). Mean dose of trihexyphenidyl was 16.25 mg. The changes on the Disability section of the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS-Disability) (primary outcome), Tsui Scale, and the General Health Perception Subscale were significantly in favor of BTA. More patients treated with BTA had an improvement of at least three points on the TWSTRS-Disability (14 versus 6) and on the Tsui Scale (23 versus 12). Adverse effects were significantly less frequent in the BTA group.
                BTA is significantly more effective in the treatment of ICD, with less adverse effects. We enrolled and treated 122 patients with idiopathic cervical dystonia in a double-blind, placebo-controlled safety and efficacy study of botulinum toxin type B (BotB). Both A-responsive and A-resistant patients were enrolled. Patients received intramuscular injections of either BotB (2,500 U, 5,000 U, or 10,000 U) or placebo. The primary outcome measure of efficacy was the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Total score at 4 weeks following study drug administration. Secondary measures of efficacy were TWSTRS-Severity, -Disability, and -Pain subscale scores, and Analog Pain Assessment, Investigator Global Assessment, Patient Global Assessment, and Sickness Impact Profile scores. Duration of effect was estimated with an intent-to-treat analysis of responders. Safety measures included clinical parameters, laboratory tests, and adverse events. The primary and most of the secondary analyses indicated a statistically significant treatment effect and a dose response. BotB is safe, well tolerated, and efficacious in the treatment of cervical dystonia at the doses tested. We used turns-amplitude analysis of the EMG as a guidance for botulinum toxin (BT) treatment in 19 patients with cervical dystonia. At the first examination, muscles showing abnormal activity (> 100 turns/sec at rest) were given BT 75 units (10 patients) or placebo (9 patients). At subsequent examinations, about 6, 12 and 18 weeks after the start, BT 75 units were given to all hyperactive muscles. Six weeks after the first BT treatment the sternocleidomastoid muscle contralateral to the involuntary head rotation and the ipsilateral and contralateral posterior neck muscles (PNM) showed a reduction of involuntary activity, as indicated by reduced turns/sec and mean amplitude at rest. Similar changes were seen when comparing BT treatment with placebo. The reduction was greater in the contralateral sternocleidomastoid muscle than in PNM, suggesting that PNM need higher doses of BT. At maximal voluntary contraction, BT treated muscles showed unchanged turns/sec (5/6 tests), decreased mean amplitude and increased ratio (turns/amplitude). This may reflect a functional random loss of muscle fibres, combined with inability to activate all motor units. A high (89%) clinical success rate with BT therapy was obtained, and it is concluded that quantitative EMG is a useful tool for the precise identification of hyperactive muscles, for optimal placing of the injection cannula and for unbiased monitoring of the treatment effect. Botulinum toxin injections were given to 23 patients with cervical dystonia in a double-blind, placebo-controlled, crossover study. Each patient was randomly given 100 units of botulinum A toxin and placebo in two respective sets of injections into the two most active contracting neck muscles at least 3 months apart. Before and 3 weeks after each set of injections, the cervical dystonia was "blindly" scored by the investigator. Each patient was also asked to independently score the improvement of the dystonia and neck pain. Four patients dropped out and one patient showed spontaneous remission. The remaining 18 patients completed the study and showed a significant improvement after the injections of botulinum toxin in comparison with that of the placebo. The effect started about 1 week after injection and the maximal effect lasted about 11 weeks in patients with a satisfactory response. The neck pain was satisfactorily relieved in 9 of 10 patients affected. There were no significant side effects. Thus, botulinum toxin injection is effective in treating cervical dystonias; injection of a higher dose of botulinum toxin in a greater number of neck muscles is required for those patients with complex cervical dystonia. 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 > or = 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. To determine the safety and efficacy of botulinum toxin type B (BoNT/B) in patients with type A-resistant cervical dystonia (CD).
                Local intramuscular injections of BoNT are an effective therapy for CD. After repeated use, some patients become resistant to therapy. BoNT/B, effective in type A toxin-responsive patients, is proposed as an alternative therapy for type A-resistant patients.
                The authors performed a 16-week, double-blind, placebo-controlled trial of BoNT/B in type A-resistant patients with CD. After resistance to therapy was confirmed with the frontalis-type A test, placebo or 10,000 U BoNT/B was administered in a single session into two to four clinically involved muscles. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) was the primary efficacy measurement. TWSTRS-Total, three visual analog scales (Patient Global Assessment of Change, Principal Investigator Global Assessment of Change, Patient Analog Pain Assessment), and adverse events were assessed at baseline and weeks 2, 4, 8, 12, and 16.
                A total of 77 patients participated (38 placebo, 39 active). Improvements in severity, disability, and pain were documented in the BoNT/B-treated group. TWSTRS-Total scores were improved in the BoNT/B-treated group at weeks 4 (p = 0.0001), 8 (p = 0.0002), and 12 (p = 0.0129). All three visual analog scales demonstrated improvements at week 4 (p < 0.0001, 0.0001, and 0.001). A Kaplan-Meier analysis supported a duration of effect of 12 to 16 weeks in the active group. Dry mouth and dysphagia were self-limited adverse effects, reported more commonly in the BoNT/B group.
                Botulinum toxin type B (BoNT/B) (NeuroBloc) is safe and efficacious for the management of patients with type A-resistant cervical dystonia with an estimated duration of treatment effect of 12 to 16 weeks. To determine the safety and efficacy of botulinum toxin type B (BoNT/B) in patients with cervical dystonia (CD).
                BoNT/B is a form of chemodenervation therapy for the treatment of patients with CD.
                The authors performed a 16-week, randomized, multicenter, double-blind, placebo-controlled trial of BoNT/B in patients with CD who continue to respond to botulinum toxin type A. Placebo, or 5,000 U or 10,000 U of BoNT/B was administered in two to four muscles involved clinically in CD. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Total score at week 4 was the primary efficacy measure. Clinical assessments and adverse events were recorded for treatment day 1 and at weeks 2, 4, 8, 12, and 16.
                A total of 109 patients were enrolled randomly across all three treatment groups. The mean improvement in the TWSTRS-Total scores in each group at week 4 was 4.3 (placebo), 9.3 (5,000 U), and 11.7 (10,000 U). For the prospectively defined primary contrast (10,000 U versus placebo), highly significant differences were noted for the primary (TWSTRS-Total, baseline to week 4, p = 0.0004) and supportive secondary (Patient Global Assessment, baseline to week 4, p = 0.0001) outcome measures. Improvement in pain, disability, and severity of CD occurred for patients who were treated with BoNT/B when compared with placebo-treated patients. Overall, improvements associated with BoNT/B treatment were greatest for patients who received the 10,000-U dose. The duration of treatment effect for BoNT/B was 12 to 16 weeks for both doses.
                Botulinum toxin type B (NeuroBloc) is safe and efficacious at 5,000 U and 10,000 U for the management of patients with cervical dystonia. To evaluate the effect of a single injection of 500 U of botulinum toxin A (BTX-A; Dysport) on use of oral rescue medication, bladder compliance, continence and quality of life in a randomized, placebo-controlled, double-blind study in patients with incontinence due to neurogenic detrusor overactivity. As this group of patients often have severe symptoms, oral tolterodine was allowed as rescue medication and the amount of tolterodine consumed was our primary endpoint.
                A total of 31 patients with urinary leakage due to spinal cord injury, myelomeningocele, trauma at birth, multiple sclerosis and myelitis of another cause were randomized to intravesical injections of either 500 U of BTX-A or placebo. Intake of tolterodine and episodes of urinary leakage were registered. Cystometry was performed after 6, 12 and 26 weeks and quality of life was assessed.
                Patients in the BTX-A group had a significantly lower intake of tolterodine throughout the study compared to those in the placebo group (p=0.003). Cystometric capacity was significantly higher at 6 (p<0.001) and 12 weeks (p=0.026) and maximum detrusor pressure and frequency of urinary leakage were significantly (p<0.01) lower during follow-up in the BTX-A group compared to the placebo group. In addition, many quality-of-life parameters were significantly improved in the BTX-A group compared to the placebo group.
                Intravesical injection of 500 U of BTX-A in patients with neurogenic detrusor instability was shown to be an effective treatment which reduced use of oral medication, high detrusor pressure and frequency of urinary leakage during the overall study period of 26 weeks. Quality of life was also significantly improved. In a randomised, double-blind study, the effects of intramuscular injection of botulinum toxin type A (BtA) into the upper limb were compared with those of normal saline solution in 14 patients with cerebral palsy; their mean age was 9 years. Range of movement and function were assessed before injection and at 2 and 12 weeks after injection. BtA injection significantly increased maximum active elbow and thumb extension and significantly reduced tone at wrist and elbow. The hand grasp-and-release score improved, representing a modest functional change, but fine motor function, assessed by the ability to pick up coins, did not improve and in some cases deteriorated temporarily. The most notable subjective change was the cosmetic benefit of reduced involuntary elbow flexion. The tone-reducing effect of BtA was clinically detectable in comparison with the placebo and patients and parents perceived the change as beneficial. The median of changes in the treatment group was small but the range was large, suggesting that BtA can be useful in selected patients.
A single injection of BtB was effective and safe for treating cervical dystonia. Long-term uncontrolled studies suggested that further injection cycles continue to work for most patients. 
Future research should explore technical factors such as the optimum treatment intervals and use of image or electromyographic guidance for administration. Other issues include service delivery, quality of life, long-term efficacy and safety, and the relative indications for BtA, BtB and other treatments such as deep brain stimulation