British Neurotoxin Network recommendations for managing cervical dystonia in patients with a poor response to botulinum toxin.

Botulinum toxin (BoNT) injections are an effective treatment for cervical dystonia. Approximately 20% of patients eventually stop BoNT treatment, mostly because of treatment failure. These recommendations review the different therapeutic interventions for optimising the treatment in secondary poor responder patients. Immunoresistance has become less common over the years, but the diagnosis has to be addressed with a frontalis test or an Extensor Digitorum Brevis test. In case of immunoresistance to BoNT-A, we discuss the place the different therapeutic options (BoNT-A holidays, BoNT-B injections, alternative BoNT-A injections, deep brain stimulation). When poor responders are not immunoresistant, they benefit from reviewing (1) injections technique with electromyography or ultrasound guidance, (2) muscles selection and (3) dose of BoNT. In addition, in both scenarios, a holistic approach including drug treatment, retraining and psychological support is valuable in the management of these complex and severe cervical dystonia.

The use of botulinum toxin injections to manage drooling in amyotrophic lateral sclerosis/motor neurone disease: a systematic review.

Difficulty in managing oral secretions is commonly experienced by patients with amyotrophic lateral sclerosis (ALS)/motor neurone disease (MND) and associated bulbar weakness including dysphagia. There are no definitive evidence-based treatment guidelines to manage the distressing symptom of drooling. We reviewed the evidence for the effectiveness of botulinum toxin injections to reduce saliva in ALS/MND. The search strategy was conducted in four stages: (1) electronic search of relevant databases, (2) hand searches of all international ALS/MND symposium journals, (3) email request to MND care centres in the UK and Ireland, and (4) hand searching of reference lists. All studies were critically appraised and relevant data extracted. Botulinum toxin type A and type B were analysed separately. Due to heterogeneity, it was not possible to calculate a pooled estimate of effect. Twelve studies met the inclusion criteria (9 for type A and 3 for type B). Only two randomised controlled trials were identified. Study sample sizes were small with a mean of 12.5 subjects. The most frequently reported outcomes were weight of cotton rolls and number of tissues used. All studies claimed the intervention tested was effective, but only seven studies (4 for type A and 3 for type B) reported statistically significant differences. Although there is evidence to suggest that botulinum toxin B can reduce drooling, the evidence base is limited by a lack of randomized controlled trials. Evidence to support the use of botulinum toxin A is weaker. Larger trials will help remove the uncertainty practitioners face in treating this disabling symptom.

MOG-antibody-associated hypertrophic pachymeningitis.

BACKGROUND: The clinical spectrum of myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease is expanding. OBJECTIVE: To describe an unusual case of MOG-antibody-associated hypertrophic pachymeningitis (HP). METHODS: Case study. RESULTS: A 57-year-old female presented with a generalised seizure on a background of 3 months history of progressive cognitive decline and behavioural changes. Brain Magnetic Resonance Imaging (MRI) revealed widespread pachymeningeal enhancement and hyperintense signal in both hippocampi. Cerebrospinal Fluid (CSF) examination was normal. The patient was found positive for MOG-antibody. She clinically improved with steroids and the MRI abnormalities completely resolved. CONCLUSIONS: Clinicians might consider testing for MOG-antibody in cases with HP.

Somatotopy in the Human Somatosensory System.

Previous functional magnetic resonance imaging (fMRI) studies have demonstrated digit somatotopy in primary somatosensory cortex (SI), and even shown that at high spatial resolution it is possible to resolve within-digit somatotopy. However, fMRI studies have failed to resolve the spatial organisation of digit representations in secondary somatosensory cortex (SII). One of the major limitations of high spatial resolution fMRI studies of the somatosensory system has been the long acquisition time needed to acquire slices spanning both SI and SII. Here, we exploit the increased blood oxygenation level dependent contrast of ultra-high-field (7 Tesla) fMRI and the use of multiband imaging to study the topographic organisation in SI and SII with high spatial resolution at the individual subject level. A total of n = 6 subjects underwent vibrotactile stimulation of their face, hand digits and foot (body imaging) and their individual hand digits (digit mapping) for each left and right sides of the body. In addition, n = 2 subjects participated only in the body imaging experiment on both their left and right sides. We show an orderly representation of the face, hand digits and foot in contralateral primary cortex in each individual subject. In SII, there is clear separation of the body areas of the face, hand and foot but the spatial organisation varies across individual subjects. However, separate representation of the individual digits of the hand in SII could not be resolved, even at the spatial resolution of 1.5 mm due to largely overlapping representations.