Background
Diagnosis of focal dystonia is based on clinical grounds and is therefore open to bias. To date, diagnostic guidelines have been only proposed for blepharospasm and laryngeal dystonia. To ...provide practical guidance for clinicians with less expertise in dystonia, a group of Italian Movement Disorder experts formulated clinical diagnostic recommendations for cervical, oromandibular, and limb dystonia.
Methods
A panel of four neurologists generated a list of clinical items related to the motor phenomenology of the examined focal dystonias and a list of clinical features characterizing neurological/non-neurological conditions mimicking dystonia. Thereafter, ten additional expert neurologists assessed the diagnostic relevance of the selected features and the content validity ratio was calculated. The clinical features reaching a content validity ratio > 0.5 contributed to the final recommendations.
Results
The recommendations retained patterned and repetitive movements/postures as the core feature of dystonia in different body parts. If present, a sensory trick confirmed diagnosis of dystonia. In the patients who did not manifest sensory trick, active exclusion of clinical features related to conditions mimicking dystonia (features that would be expected to be absent in dystonia) would be necessary for dystonia to be diagnosed.
Discussion
Although reliability, sensitivity, and specificity of the recommendations are yet to be demonstrated, information from the present study would hopefully facilitate diagnostic approach to focal dystonias in the clinical practice and would be the basis for future validated diagnostic guidelines.
Background
The coronavirus disease 2019 (COVID-19) pandemic has severely impacted the Italian healthcare system, underscoring a dramatic shortage of specialized doctors in many disciplines. The ...situation affected the activity of the residents in neurology, who were also offered the possibility of being formally hired before their training completion.
Aims
(1) To showcase examples of clinical and research activity of residents in neurology during the COVID-19 pandemic in Italy and (2) to illustrate the point of view of Italian residents in neurology about the possibility of being hired before the completion of their residency program.
Results
Real-life reports from several areas in Lombardia—one of the Italian regions more affected by COVID-19—show that residents in neurology gave an outstanding demonstration of generosity, collaboration, reliability, and adaptation to the changing environment, while continuing their clinical training and research activities. A very small minority of the residents participated in the dedicated selections for being hired before completion of their training program. The large majority of them prioritized their training over the option of earlier employment.
Conclusions
Italian residents in neurology generously contributed to the healthcare management of the COVID-19 pandemic in many ways, while remaining determined to pursue their training. Neurology is a rapidly evolving clinical field due to continuous diagnostic and therapeutic progress. Stakeholders need to listen to the strong message conveyed by our residents in neurology and endeavor to provide them with the most adequate training, to ensure high quality of care and excellence in research in the future.
The excitability of inhibitory circuits in patients with writer's cramp is reduced at multiple levels within the sensorimotor system, including the primary motor hand area (M1). Although this may ...play a major role in the pathophysiology of writer's cramp, it is still unclear what factors may cause the imbalance between inhibition and excitation to arise. One possibility is that homeostatic mechanisms that keep cortical excitability within a normal physiological range are impaired. In eight patients with writer's cramp and eight healthy age-matched controls, we combined low-frequency repetitive transcranial magnetic stimulation (rTMS) with transcranial direct current stimulation (TDCS) to probe regional homeostatic plasticity of the left M1. Confirming our previous study (Siebner et al., J Neurosci 2004; 24: 3379–85), ‘facilitatory’ preconditioning of the M1 with anodal TDCS enhanced the inhibitory effect of subsequent 1 Hz rTMS on corticospinal excitability. Conversely, ‘inhibitory’ preconditioning with cathodal TDCS reversed the after effect of 1 Hz rTMS, producing an increase in corticospinal excitability. The results were quite different in patients with writer's cramp. Following preconditioning with TDCS, 1 Hz rTMS induced no consistent changes in corticospinal excitability, indicating a loss of the normal ‘homeostatic’ response pattern. In addition, the normal inhibitory effect of preconditioning with cathodal TDCS was absent. The present data suggest that homeostatic mechanisms that stabilize excitability levels within a useful dynamic range are impaired in patients with writer's cramp. We propose that a faulty homeostatic response to acute increases in corticospinal excitability favours maladaptive motor plasticity. The role of homeostatic-like plasticity in the pathophysiology of task-specific dystonias warrants further study.
In the past few years, treatment of multiple myeloma has undergone a deep change for the employment of novel treatment comprising proteasome inhibitors. Bortezomib is a first-line drug in therapy of ...multiple myeloma. The onset of peripheral neuropathy is a dose-limiting collateral effect of the drug. This neuropathy is a distal symmetric neuropathy that affects both large and small fibers. Nerve conduction study (NCS) can be used for the diagnosis of bortezomib neuropathy, but this technique demonstrates alterations of the large nerve fibers. Sudoscan is a novel technique utilized to offer an evaluation of sudomotor function. The main objective of this study was to compare the sensitivity and diagnostic specificity of Sudoscan with respect to the nerve conduction study after bortezomib treatment.
A total of 18 multiple myeloma patients were studied, 10 (55.5%) men and 8 (44.5%) women. Patients were analyzed at baseline and after 6 months of treatment with bortezomib. Subjects were submitted to nerve conduction study and electrochemical skin conductance evaluation with the Sudoscan device. Patients were also submitted to a clinical measure of pain and neuropathy.
At baseline NCS showed that only the mean sural SAP amplitude was below the 2SD lower limit of normal in 3 (16.7%) patients, while at same time we found an alteration of Sudoscan profiles in 2 (11.1%) patients. After 6 months of treatment, the NCS profiles were altered in 13 (72.2%) patients, and the Sudoscan profiles were modified in 11 (61.1%) subjects.
Our results suggest that Sudoscan can be considered for the diagnosis of bortezomib-induced neuropathy. It is objective, reproducible, and surely easier than the traditional nerve conduction study. Sudoscan may be a useful help to manage the therapeutic interventions in multiple myeloma.
Background:
Brain tumors can cause different changes in excitation and inhibition at the neuronal network level. These changes can be generated from mechanical and cellular alterations, often ...manifesting clinically as seizures.
Objective/Hypothesis:
The effects of brain tumors on cortical excitability (CE) have not yet been well-evaluated. The aim of the current study was to further investigate cortical–cortical and cortical–spinal excitability in patients with brain tumors using a more extensive transcranial magnetic stimulation protocol.
Methods:
We evaluated CE on 12 consecutive patients with lesions within or close to the precentral gyrus, as well as in the subcortical white matter motor pathways. We assessed resting and active motor threshold, short-latency intracortical inhibition (SICI), intracortical facilitation (ICF), short-latency afferent inhibition (SAI), long-latency afferent inhibition, cortical silent period, and interhemispheric inhibition.
Results:
CE was reduced in patients with brain tumors than in healthy controls. In addition, SICI, ICF, and SAI were lower in the affected hemisphere compared to the unaffected and healthy controls.
Conclusions:
CE is abnormal in hemispheres affected by brain tumors. Further studies are needed to determine if CE is related with motor impairment.
Repetitive transcranial magnetic stimulation (rTMS) or repetitive electrical peripheral nerve stimulation (rENS) can induce
changes in the excitability of the human motor cortex (M1) that is often ...short-lasting and variable, and occurs only after
prolonged periods of stimulation. In 10 healthy volunteers, we used a new repetitive paired associative stimulation (rPAS)
protocol to facilitate and prolong the effects of rENS and rTMS on cortical excitability. Sub-motor threshold 5 Hz rENS of
the right median nerve was synchronized with submotor threshold 5 Hz rTMS of the left M1 at a constant interval for 2 min.
The interstimulus interval (ISI) between the peripheral stimulus and the transcranial stimulation was set at 10 ms (5 Hz rPAS 10ms ) or 25 ms (5 Hz rPAS 25ms ). TMS was given over the hot spot of the right abductor pollicis brevis (APB) muscle. Before and after rPAS, we measured
the amplitude of the unconditioned motor evoked potential (MEP), intracortical inhibition (ICI) and facilitation (ICF), short-
and long-latency afferent inhibition (SAI and LAI) in the conditioned M1. The 5 Hz rPAS 25ms protocol but not the 5 Hz rPAS10 ms protocol caused a somatotopically specific increase in mean MEP amplitudes in the relaxed APB muscle. The 5 Hz rPAS 25ms protocol also led to a loss of SAI, but there was no correlation between individual changes in SAI and corticospinal excitability.
These after-effects were still present 6 h after 5 Hz rPAS 25ms . There was no consistent effect on ICI, ICF and LAI. The 5 Hz rENS and 5 Hz rTMS protocols failed to induce any change in
corticospinal excitability when given alone. These findings show that 2 min of 5 Hz rPAS 25ms produce a long-lasting and somatotopically specific increase in corticospinal excitability, presumably by sensorimotor disinhibition.
Abstract Background Primary motor cortex (M1) is relatively spared in the early stages of Alzheimer’s disease (AD). Objective Aim of the present study was to investigate whether abnormal M1 synaptic ...plasticity is present at an early stage of AD. We employed an electrophysiological protocol, named rapid paired associative stimulation (rPAS), involving repetitive transcranial magnetic stimulation (rTMS) paired with electrical stimulation of the contralateral median nerve, that modifies corticospinal excitability and short latency afferent inhibition (SAI). Methods We studied 10 patients with a diagnosis of probable mild AD according to the Mini Mental State Examination score (minimum 21) and 14 age-matched control subjects. Motor evoked potentials (MEP) amplitudes and short-afferent inhibition (SAI) were measured at baseline before and for up to 60 min after 5Hz-rPAS in abductor pollicis brevis (APB). rPAS consisted of 600 pairs of transcranial magnetic stimuli, at a rate of 5 Hz for 2 min, coupled with electrical median nerve stimulation preceding TMS over the contralateral M1 at an inter-stimulus interval of 25 ms. Results Baseline SAI was significantly reduced in AD patients. In the control subjects rPAS induced a significant increase in MEP amplitudes and a decrease of SAI in the APB muscle persistently for up to 1 h. Conversely 5Hz-rPAS did not induce any significant changes in MEP amplitudes and SAI in mild AD patients. Conclusions Sensory-motor plasticity is impaired in the motor cortex of AD at an early stage of the disease.
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