Review article: botulinum toxin in the therapy of gastrointestinal motility disorders. (17/98)

Since 1980, botulinum toxin has been employed for the treatment of various voluntary muscle spastic disorders in the fields of neurology and ophthalmology. More recently, botulinum toxin has been proved to be effective in the therapy of dyskinetic smooth muscle disorders of the gastrointestinal tract. Achalasia and anal fissure are the gastrointestinal disorders in which botulinum toxin therapy has been most extensively investigated. Botulinum toxin is the best treatment option for achalasia in patients whose condition makes them unfit for pneumatic dilation or surgery. In anal fissure, botulinum toxin is highly effective and may become the treatment of choice. In the future, botulinum toxin application in the gastrointestinal tract will be extended to many other gastrointestinal disorders, such as non-achalasic motor disorders of the oesophagus, dysfunction of Oddi's sphincter, achalasia of the internal anal sphincter and others. This article describes the mechanism of action, rationale of employment, indications and side-effects of botulinum toxin application in smooth muscle disorders of the gastrointestinal tract, and compares the results of different techniques of botulinum toxin therapeutic application.  (+info)

Botulinum toxins: pharmacology and its current therapeutic evidence for use. (18/98)

Botulinum toxins are, as a group, among the most potent neuromuscular toxins known, yet they are clinically useful in the management of conditions associated with muscular and glandular over-activity. Botulinum toxins act by preventing release of acetylcholine into the neuromuscular junction. While botulinum toxin type A is commonly available, different manufacturers produce specific products, which are not directly interchangeable and should not be considered as generically equivalent formulations. Type B is also available in the market. Each formulation of botulinum toxin is unique with distinct dosing, efficacy and safety profiles for each use to which it is applied. Botulinum toxin type A is the treatment of choice based on its depth of evidence in dystonias and most other conditions. Botulinum toxin type A is established as useful in the management of spasticity, tremors, headache prophylaxis and several other neurological conditions. Active research is underway to determine the parameters for which the type B toxin can be used in these conditions, as covered in this review. Botulinum toxin use has spread to several fields of medicine.  (+info)

Alien hand syndrome: contradictive movement and disorder of color discrimination. (19/98)

A senile Chinese female patient with alien hand syndrome of vascular etiology is reported. This case exhibited contradictive movement, left-lateral paresis and disorder of color discrimination, which might be a new subtype of the alien limb syndrome.  (+info)

Randomized controlled trial of botulinum toxin versus laparoscopic heller myotomy for esophageal achalasia. (20/98)

OBJECTIVE: To compare laparoscopic cardia myotomy and fundoplication with botulinum toxin (BoTx) injection in patients with esophageal achalasia. SUMMARY BACKGROUND DATA: Although myotomy is thought to offer better results, recent studies have reported 80% success rates after 2 BoTx injections a month apart. No randomized controlled trials comparing the 2 treatments have been published so far. MATERIALS AND METHODS: Newly diagnosed achalasia patients were randomly assigned to BoTx injection or laparoscopic myotomy. Symptoms were scored; lower esophageal sphincter resting and nadir pressures were measured by manometry; barium swallow was used to assess esophageal diameter pre- and post-treatment. Eight to one hundred units of BoTx were injected twice, a month apart, at the esophagogastric junction. Myotomy included anterior partial (Dor) or Nissen fundoplication. RESULTS: Eighty patients were involved in the study: 40 received BoTx and 40 underwent myotomy. Mortality was nil. One surgical patient bled from the trocar site. Median hospital stay was 6 days for surgery; BoTox patients were treated as day-hospital admissions. All patients completed the follow-up. After 6 months, the results in the 2 groups were comparable, although symptom scores improved more in surgical patients (82% confidence interval [CI] 76-89 vs. 66% CI 57-75, P < 0.05). The drop in lower esophageal sphincter pressure was similar in the 2 groups; the reduction in esophageal diameter was greater after surgery (19% CI 13-26 vs. 5% CI 2-11, P < 0.05). Later on, symptoms recurred in 65% of the BoTx-treated patients and the probability of being symptom-free at 2 years was 87.5% after surgery and 34% after BoTx (P < 0.05). CONCLUSION: Laparoscopic myotomy is as safe as BoTx treatment and is a 1-shot treatment that cures achalasia in most patients. BoTx should be reserved for patients who are unfit for surgery or as a bridge to more effective therapies, such as surgery or endoscopic dilation.  (+info)

Laryngeal electromyography in movement disorders: preliminary data. (21/98)

This study describes preliminary laryngeal electromyography (LEMG) data and botulinum toxin treatment in patients with dysphonia due to movement disorders. Twenty-five patients who had been clinically selected for botulinum toxin administration were examined, 19 with suspected laryngeal dystonia or spasmodic dysphonia (SD), 5 with vocal tremor, and 1 with Gilles de la Tourette syndrome (GTS). LEMG evaluations were performed before botulinum toxin administration using monopolar electrodes. Electromyography was consistent with dystonia in 14 patients and normal in 5, and differences in frequency suggesting essential tremor in 3 and Parkinson tremors in 2. The different LEMG patterns and significant improvement in our patients from botulinum toxin therapy has led us to perform laryngeal electromyography as a routine in UNICAMP movement disorders ambulatory.  (+info)

Factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin. (22/98)

OBJECTIVE: To identify factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin (BTX). METHODS: 47 patients with writer's cramp were treated with BTX and were evaluated by the same neurologists at initial referral, after each BTX injection, and when the effect of BTX was maximal at the time of the study. Patients and examiners simultaneously and independently rated the efficacy of BTX injections. Self assessment was a global clinical impression of the impact of treatment on writing quality, writing speed, writing errors, and legibility of handwriting; for objective assessment, the examiners used the Burke-Fahn-Marsden (BFM) scale. RESULTS: On the BFM scale, there was a significant improvement (p<0.0001) in both severity and disability scores. Patients with a pronation/flexion pattern of dystonia showed the best and the most sustained improvement. Primary writing tremor was little improved. There was a correlation between the self assessment score and the Burke-Fahn-Marsden score. Benefit was maintained over time CONCLUSIONS: These results have implications for the identification of patients most likely to benefit from BTX injections.  (+info)

Effect of forelimb use on postnatal development of the forelimb motor representation in primary motor cortex of the cat. (23/98)

In the cat, the motor representation in motor cortex develops between wk 8 and wk 13. Motor map development is accompanied by a decrease in the current thresholds for evoking movements with a concomitant increase in the number of effective sites, an increase in the distal representation, and the representation of multijoint synergies. In this study we used intracortical microstimulation in anesthetized cats to examine how forelimb motor experiences influence development of map characteristics. To promote skilled movements during wks 8-13, animals were engaged in daily performance of a prehension task. Forelimb movements were prevented by intramuscular botulinum toxin injection or restraint. To determine whether experience-dependent changes were permanent, we examined the map in different animals between 1 wk and 1 yr after cessation of testing. Promoting forelimb use resulted in an increase in the number of sites from which multiple joint effects were produced by stimulation and the number of joints represented at those sites. The effect was maximal at 1 wk after cessation of testing, and became progressively less at 1 mo and at 4 mo. Preventing limb use resulted in a decreased number of effective sites, an increase in current thresholds for evoking responses, and a decreased representation of joints at multijoint sites. Our findings show that the motor map can respond to novel motor demands as it is forming during development but that it reverts back to one with the properties of a map in a control animal if those demands are not maintained in the animal's behavioral repertoire.  (+info)

Relationship of brain-derived neurotrophic factor and its receptor TrkB to altered inhibitory prefrontal circuitry in schizophrenia. (24/98)

Dysfunction of inhibitory neurons in the prefrontal cortex (PFC), represented by decreased expression of GABA-related genes such as the 67 kDa isoform of glutamate decarboxylase (GAD67) and parvalbumin (PV), appears to contribute to cognitive deficits in subjects with schizophrenia. We investigated the involvement of signaling mediated by brain-derived neurotrophic factor (BDNF) and its receptor tyrosine kinase TrkB in producing the altered GABA-related gene expression in schizophrenia. In 15 pairs of subjects with schizophrenia and matched control subjects, both BDNF and TrkB mRNA levels, as assessed by in situ hybridization, were significantly decreased in the PFC of the subjects with schizophrenia, whereas the levels of mRNA encoding the receptor tyrosine kinase for neurotrophin-3, TrkC, were unchanged. In this cohort, within-pair changes in TrkB mRNA levels were significantly correlated with those in both GAD67 and PV mRNA levels. Decreased BDNF, TrkB, and GAD67 mRNA levels were replicated in a second cohort of 12 subject pairs. In the combined cohorts, the correlation between within-pair changes in TrkB and GAD67 mRNA levels was significantly stronger than the correlation between the changes in BDNF and GAD67 mRNA levels. Neither BDNF nor TrkB mRNA levels were changed in the PFC of monkeys after a long-term exposure to haloperidol. Genetically introduced decreases in TrkB expression, but not in BDNF expression, also resulted in decreased GAD67 and PV mRNA levels in the PFC of adult mice; in addition, the cellular pattern of altered GAD67 mRNA expression paralleled that present in schizophrenia. Decreased TrkB signaling appears to underlie the dysfunction of inhibitory neurons in the PFC of subjects with schizophrenia.  (+info)