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Background: Italy was one of the first affected countries by coronavirus disease 2019 (COVID-19) pandemic. Public health measures like quarantine or national lockdown were adopted, with negative psychological and clinical effects on patients with chronic diseases. To investigate the impact of lockdown on patients with multiple sclerosis (MS), we developed a 36 items self-report questionnaire. Methods: Questionnaires were emailed to 120 patients with MS and 100 with chronic migraine (CM) as a control group, matched for age, sex, and education. The questionnaire was divided into five domains, evaluating concerns about 1) MS and therapy during COVID-19 pandemic, 2) personal and family caregiving, 3) working activities, 4) general and disease-related emotions during the lockdown, 5) future expectations concerning health status, social life, and working activity. Results: patients with MS had higher scores than those with CM in domains 4 and 5, investigating respectively general and disease-related emotions and future expectations (p= 0.05 and 0.02 respectively). About half of the patients with MS expressed some concern about the need to continue their therapy during the pandemic compared to people with CM (p= 0.0002). Conclusions: Covid-19 pandemic had a more negative impact on psychological status of patients with MS compared with those with CM

Background The disease-modifying therapies (DMTs) largely used in multiple sclerosis (MS) may result in higher infectious risk. Objective We aimed to investigate the infectious risk in DMT-treated MS patients. Methods MS patients were evaluated for infectious risk before starting, switching or during DMT. Results In this three-year observational cohort study 174 MS patients were enrolled. Among them, 18 patients were anti-HBc + and 19 patients were QuantiFERON®-TB Gold In-Tube (QFT) + . No patients with anti-HBc + showed a detectable HBV-DNA and all started DMT. Among QTB + patients, 17 latent TB infections (LTBIs) and 2 active TB infections (TBIs) were identified. After one month of LTBI prophylaxis or TB treatment, respectively, all patients started DMTs. Overall, 149 started DMTs. During DMTs, one ocrelizumab-treated patient with anti-HBc + developed HBV reactivation and six patients (3 on natalizumab, 2 on ocrelizumab and 1 on IFN-β) showed reactivation of HSV-1, with detectable plasma DNA. Finally, 1 cladribine-treated patient experienced VZV reactivation. All the reactivations of latent infections have been successfully treated. Conclusion Screening of infectious diseases in DMT candidate MS patients helps to mitigate the infectious risk. During DMTs, a regular assessment of infectious risk allows to avoid discontinuing MS therapy and guarantees a higher degree of safety.

To study the effects of a standard acute medication withdrawal program on short-term cortical plasticity mechanisms in patients with medication overuse headache (MOH). Thirteen patients with MOH and 16 healthy volunteers underwent repetitive transcranial magnetic stimulation (rTMS) over the left motor cortex; in patients with MOH, recordings were performed before and after a 3-week medication withdrawal program. Ten trains of 10 stimuli each (120% resting motor threshold) were delivered at 1 Hz or 5 Hz in two separate sessions in a randomised order. Motor evoked potential (MEP) amplitudes were measured from the right first dorsal interosseous muscle and the slope of the linear regression line from the first to the tenth stimuli was calculated for each participant. All subjects exhibited MEP amplitude inhibition in response to 1 Hz rTMS. Alternatively, the 5-Hz trains of rTMS inhibited rather than potentiated MEP amplitudes in patients with MOH. The physiological potentiating effect of 5 Hz rTMS on MEP amplitudes was restored after drug withdrawal and in proportion with the percentage reduction in monthly headache days in patients with MOH. The results suggest that acute medication withdrawal normalises brain responses in patients with MOH. Clinical improvements after medication withdrawal may reflect the reversal of neurophysiological dysfunction. Accordingly, medication withdrawal should be offered to patients with MOH as early as possible in order to prevent the development of more pronounced alterations in brain plasticity.

Background and purpose Stroke-associated pneumonia (SAP) affects 10 to 38% of patients in the acute phase of stroke. Stroke patients diagnosed with dysphagia have an 11-fold higher risk of developing SAP. Thus, identifying dysphagic patients through a highly accurate screening tool might be crucial in reducing the incidence of SAP. We present a case–control study designed to evaluate efficacy in reducing the risk of SAP between two swallowing screening tools, the classic water swallow test (WST) and a recently validated tool such as the GLOBE-3S (the Sapienza GLObal Bedside Evaluation of Swallowing after Stroke), which is a highly sensitive swallowing screening tool particularly accurate in detecting silent aspiration as well. Methods We analyzed the occurrence of dysphagia in 100 acute stroke patients distributed in two groups: half were screened with WST and the other half with GLOBE-3S. Results Dysphagia was diagnosed in 28 patients. The main result is that, among patients who passed the dysphagia screenings, none of those screened with the GLOBE-3S method developed pneumonia compared to 31.82% in the WST group. Discriminant function analysis (DFA) showed that NIH Stroke Scale (NIHSS) score and the dysphagia screening method (i.e., GLOBE-3S vs. WST) were the two main factors in the SAP’s predicting model and the only significant ones per se. Conclusions The new GLOBE-3S screening test can reduce the risk of SAP compared to WST.

Most patients with multiple sclerosis presenting with a relapsing–remitting disease course at diagnosis transition to secondary progressive multiple sclerosis (SPMS) 1–2 decades after onset. SPMS is characterized by predominant neurodegeneration and atrophy. These pathogenic hallmarks result in unsatisfactory treatment response in SPMS patients. Therefore, early diagnosis of SPMS is necessary for prompt treatment decisions. The aim of this review was to assess neurophysiological and fluid biomarkers that have the potential to monitor disease progression and support early SPMS diagnosis. We performed a systematic review of studies that analyzed the role of neurophysiological techniques and fluid biomarkers in supporting SPMS diagnosis using the preferred reporting items for systematic reviews and meta-analyses statement. From our initial search, we selected 24 relevant articles on neurophysiological biomarkers and 55 articles on fluid biomarkers. To date, no neurophysiological or fluid biomarker is sufficiently validated to support the early diagnosis of SPMS. Neurophysiological measurements, including short interval intracortical inhibition and somatosensory temporal discrimination threshold, and the neurofilament light chain fluid biomarker seem to be the most promising. Cross-sectional studies on an adequate number of patients followed by longitudinal studies are needed to confirm the diagnostic and prognostic value of these biomarkers. A combination of neurophysiological and fluid biomarkers may be more sensitive in detecting SPMS conversion.

Background and purpose Dysphagia occurs in up to 50% of all patients with acute stroke. There is debate regarding which is the most effective screening tool in identifying aspiration in patients with acute stroke. We assessed the accuracy of the Sapienza Global Bedside Evaluation of Swallowing after Stroke (GLOBE-3S), which combines the Toronto Bedside Swallowing Screening Test (TOR-BSST©) with oxygen desaturation and laryngeal elevation measurement during swallowing. Methods We prospectively enrolled consecutive patients with stroke within 72 h of symptom onset. All patients with stroke firstly underwent a standard neurological examination, then the GLOBE-3S evaluation and finally the fiberoptic endoscopic evaluation of swallowing (FEES). Two different assessors, a neurologist and a speech pathologist, blind to both the clinical data and each other's evaluation, administered the GLOBE-3S and FEES examination. We assessed the accuracy of the GLOBE-3S in detecting post-stroke swallow impairment with aspiration using the FEES as the standard. Results We enrolled 50 patients with acute stroke, 28 of whom (56%) had swallowing impairment with aspiration at FEES evaluation. A total of 33 patients (66%) failed the GLOBE-3S evaluation. The GLOBE-3S reached a sensitivity of 100% and a specificity of 77.3% (negative predictive value, 100%; positive likelihood ratio, 4.34). The median time required for the GLOBE-3S to be performed was 297 s. Conclusions GLOBE-3S is quick to perform at the bedside and can accurately identify aspiration in patients with acute stroke. By including the measurement of laryngeal elevation and monitoring of oxygen desaturation, it could represent a highly sensitive instrument to avoid the misdiagnosis of silent aspirators.

Objective To study the effects of trains of repetitive transcranial magnetic stimulation (rTMS) over the motor cortex in patients with chronic migraine (CM) with or without medication overuse (MOH). Subjects and methods Thirty-two patients (CM [n = 16]; MOH [n = 16]) and 16 healthy volunteers (HVs) underwent rTMS recording. Ten trains of 10 stimuli each (120% resting motor threshold) were applied over the left motor cortex at 1 Hz or 5 Hz in random order. The amplitude of motor evoked potential (MEP) was evaluated from electromyographic recording in the first dorsal interosseous muscle. The slope of the linear regression line for the 10 stimuli for each participant was calculated using normalized data. Results rTMS-1 Hz had a normal depressive effect on MEP amplitude in all groups. rTMS-5 Hz depressed instead of potentiating MEP amplitudes in MOH patients, with a significantly different response from that in HVs and CM patients. The slope of the linear regression of MEP amplitudes was negatively correlated with pain intensity in CM patients, and with the duration of overuse headache in MOH patients. Conclusions This different plastic behaviour suggests that MOH and CM, despite exhibiting a similar clinical phenotype, have different neurophysiological learning processes, probably related to different pathophysiological mechanisms of migraine chronification.

O028. Thalamo-cortical network changes during the migraine cycle: insights from MRI-based microstructural and functional resting-state network correlation analysis Gianluca Coppola, Antonio Di Renzo, Emanuele Tinelli, Chiara Lepre, Elisa Iacovelli, Cherubino Di Lorenzo, Giorgio Di Lorenzo, Vincenzo Parisi, Mariano Serrao, Flavia Pauri, Giancarlo Fiermonte, Claudio Colonnese, Jean Schoenen, Francesco Pierelli

To evaluate trigemino-cervical-spinal reflexes (TCSRs) in a group of migraine patients during the pain-free period.TCRSs are part of a complex nocifensive response involving the cervical and the upper limb muscles, and are modulated by supraspinal inhibitory pathways; it may, thus, be possible to use TCRSs to explore the trigeminal system in migraineurs.A total of 43 migraine patients without aura (MWoA, 32 patients) or with typical aura (MWA, 11 patients) and 30 age- and sex-matched healthy subjects took part in the study. TCRSs were obtained by stimulating the supraorbital nerve and recorded from the semispinalis capitis muscle and the biceps brachii. The latency (L, msec), area (A, mVms) and recovery cycle of the reflexes were recorded. The effects of heterotopic painful stimulation on the neurophysiological parameters were studied by a validated cold pressor test (CPT).No significant changes were found between either migraine patients and controls or MWoA and MWA patients in the mean values in the L and A of TCRSs (t-test, P.05). The recovery curve of the trigemino-cervical reflexes (TCRs) was significantly faster in migraine patients than in controls, while no differences were found in the trigemino-spinal reflexes (TSRs) (t-test, P.01). Activation of the diffuse inhibitory controls through the CPT induced a significant reduction in the TCRs and TSRs area in both migraine patients and controls (paired t-test, P.01), though the extent of this reduction did not differ significantly between migraineurs and controls (t-test, P.05).Our data suggest that the pain-free period in migraine patients is characterized by a hyperexcitability of the trigeminal pathways and of their anatomical and functional connections with the upper cervical cord neurons, and that this abnormal hyperexcitability does not appear to be due to a lack of a supraspinal inhibitory modulation.

Transcranial magnetic stimulation (TMS) is a recently established technique in the neurosciences that allows the non-invasive assessment, among other parameters, of the excitability of motor cortex. Up to now, its application to sleep research has been very scarce and because of technical problems it provided contrasting results. In fact delivering one single suprathreshold magnetic stimulus easily awakes subjects, or lightens their sleep. For this reason, in the present study we assessed motor thresholds (MTs) upon rapid eye movement (REM) and non-rapid eye movement (NREM) sleep awakenings, both in the first and in the last part of the night. Taking into account that a full re-establishment of wake regional brain activity patterns upon awakening from sleep needs up to 20-30 min, it is possible to make inferences about the neurophysiological characteristics of the different sleep stages by analyzing the variables of interest immediately after provoked awakenings. Ten female volunteers slept in the lab for four consecutive nights. During the first night the MTs were collected, following a standardized procedure: 5 min before lights off, upon stage 2 awakening (second NREM period), upon REM sleep awakening (second REM period), upon the final morning awakening (always from stage 2). Results showed that MTs increased linearly from presleep wakefulness to REM sleep awakenings, and from the latter to stage 2 awakenings. There was also a time-of-night effect on MTs upon awakening from stage 2, indicating that MTs decreased from the first to the second part of the night. The increase in corticospinal excitability across the night, which parallels the fulfillment of sleep need, is consistent with the linear decrease of auditory arousal thresholds during the night. The maximal reduction of corticospinal excitability during early NREM sleep can be related to the hyperpolarization of thalamocortical neurons, and is in line with the decreased metabolic activity of motor cortices during this sleep stage. On the contrary, the increase of MTs upon REM sleep awakenings should reflect peripheral factors. We conclude that our findings legitimate the introduction of the TMS technique as a new proper tool in sleep research.

Transcranial magnetic stimulation (TMS) of the motor cortex of one hemisphere (conditioning stimulus, CS) inhibits EMG responses evoked in distal hand muscles by a magnetic stimulus given at appropriate interval later over the opposite hemisphere (test stimulus, TS). The common interpretation attributes this effect to an inhibition produced at cortical level via a transcallosal route. The variability of cortical excitability as measured by the interhemispheric paired-pulse (PP) technique has been assessed in healthy subjects in order to compare sub- and supra-threshold intensity of CS (80% versus 120% of individual motor threshold, MT). Within- and between-subject variability relating, respectively, to interhemispheric and gender differences were also assessed. Results point to an efficacy of a magnetic CS on one hemisphere in inhibiting EMG responses of the abductor digiti minimi (ADM) stimulated by a TS delivered over the opposite hemisphere in a range of intervals centered at 12ms. These reductions were produced by the 120% suprathreshold CS, while the 80% subthreshold CS did not affect EMG responses. Females showed a higher transcallosal inhibition than males, suggesting gender differences in interhemispheric connectivity that concern the anterior half of the trunk of the corpus callosum.

Neurophysiological investigations have demonstrated that there are unique fluctuations in the migraine brain functional activity between the ictal and interictal periods. Here we investigated the possibility that there are fluctuations over time also in whole brain morphometry of patients affected by episodic migraine without aura (MO). Twenty-four patients with untreated MO underwent 3T MRI scans during ( n = 10) or between attacks ( n = 14) and were compared to a group of 15 healthy volunteers (HVs). We then performed voxel-based-morphometry (VBM) analysis of structural T1-weighted MRI scans to determine if changes in brain structure were observed over the course of the migraine cycle. Interictally, MO patients had a significantly lower gray matter (GM) density within the right inferior parietal lobule, right temporal inferior gyrus, right superior temporal gyrus, and left temporal pole than did HVs. Ictally, GM density increased within the left temporal pole, bilateral insula, and right lenticular nuclei, but no areas exhibited decreased GM density. These morphometric GM changes between ictal and interictal phases suggest that abnormal structural plasticity may be an important mechanism of migraine pathology. Given the functional neuroanatomy of these areas, our findings suggest that migraine is a condition associated with global dysfunction of multisensory integration and memory processing.

Motor deficits affect patients with Alzheimer's disease only at later stages. Recent studies demonstrate that the primary motor cortex is affected by neuronal degeneration accompanied by the formation of amyloid plaques and neurofibrillary tangles. It is conceivable that neuronal loss is compensated by reorganization of the neural circuitries occurring along the natural course of the disease, thereby maintaining motor performances in daily living. Cortical motor output to upper limbs was tested via motor-evoked potentials from forearm and hand muscles elicited by transcranial magnetic stimulation of motor cortex in 16 patients with mild Alzheimer's disease without motor deficits. Motor cortex excitability was increased, and the center of gravity of motor cortical output, as represented by excitable scalp sites, showed a frontal and medial shift, without correlated changes in the site of maximal excitability (hot-spot). This may indicate functional reorganization, possibly after the neuronal loss in motor areas. Hyperexcitability might be caused by a dysregulation of the intracortical GABAergic inhibitory circuitries and selective alteration of glutamatergic neurotransmission. Such findings suggest that motor cortex hyperexcitability and reorganization allows prolonged preservation of motor function during the clinical course of Alzheimer's disease.

Background Neurophysiological investigations have demonstrated that there are distinctive fluctuations in the brain’ se lectric signals between the ictal and interictal periods of recurrent migraine. Whether structural plasticity of the brain is also an important feature of episodic migraine remains unresolved. Aim We therefore investigated the possibility that there are fluctuations over time in whole brain grey matter morphometry of patients affected by episodic migraine without aura (MO). Method Twenty-four patients with untreated MO underwent MRI scans (3-Tesla Siemens Verio) during (n = 10) or between attacks (n = 14) and were compared to a group of 15 healthy volunteers (HV). We then performed voxelbased-morphometry (VBM) analysis of structural T1-weighted MRI scans to determine if changes in brain structure were observed over the course of the migraine cycle. Results During the interictal phase, MO patients had a significantly lower grey matter (GM) density within the right inferior parietal lobule, right temporal inferior gyrus, right superior temporal gyrus, and left temporal pole than did HV. During attacks, GM density increased within the left temporal pole, bilateral insula, and right lenticular nuclei, but no areas exhibited decreased GM density. Conclusion The morphometric GM changes between ictal and interictal phases reported in the present study suggest that abnormal structural plasticity may be an important mechanism of migraine pathology. Given the functional neuroanatomy of these areas, our findings suggest that migraine is a condition associated with global dysfunction of multisensory integration and memory processing. No conflict of interest.

The most common mononeuropathy in the lower extremity involves the nerve. We retrospectively evaluated the etiological predisposing factors and clinical-neurophysiological features of 36 patients affected by peroneal mononeuropathy (PM). In 30 patients, a clear predisposing factor was identified. PM was more frequently perioperative (11 cases), associated with axonal involvement. Unexpectedly, PM was not only due to surgery close to the peroneal region, but was mostly associated with hip surgery and, rarely, with thoracic-abdominal surgery. A postural predisposing factor of PM was also frequently observed, usually associated with a pure conduction block. Conversely, most patients with bedridden predisposing factor presented axonal involvement, which was rarely associated with conduction block. In 25 of 36 PM cases, a long-term follow-up lead to an improvement (12 cases) or to good recovery (13 cases) of PM. In conclusion, our study shows that: (1) in most PM cases it is possible to identify a predisposing factor; (2) there is a good correlation between predisposing factor and neurophysiological involvement, and (3) PM usually has usually a good prognosis.

We report the clinical, serological, and neurophysiological findings in seven patients with foodborne botulism caused by ingestion of black olives in water. The clinical picture was characterized by mild symptoms with a long latency of onset and by involvement of cranial and upper limb muscles; only one patient, a child, developed respiratory failure. Spores of Clostridium botulinum were found in stools in some but not all cases. Conventional neurophysiological tests had low sensitivity; abnormal findings were present only in the patient with severe clinical involvement, in whom compound muscle action potentials (CMAPs) appeared reduced. Repetitive nerve stimulation at a high rate showed pseudofacilitation and not true posttetanic facilitation, but single-fiber electromyography (SFEMG) showed abnormalities of neuromuscular transmission in every case. Neurophysiological evaluation, particularly SFEMG, is important because it allows rapid identification of abnormal neuromuscular transmission while bioassay studies are in progress.

We report a case of a 53-year-old man with a 2-year history of progressive gait and balance disturbance, supranuclear ophthalmoparesis, mild dysarthria and dysmetria. EMG revealed a lower limb axonal sensory-motor neuropathy, while MR imaging demonstrated a small focal lesion in the right frontal lobe, mild diffuse hyperintensity of the periventricular white matter and diffuse brain atrophy. Magnetic resonance spectroscopy revealed a mild decrease in N-acetyl-aspartate peak and an increase in the choline peak in the small right frontal lesion and within 6 voxels of interest in normal appearing cerebral tissue. According to the clinical picture the diagnosis of WD was made by the positivity of PCR for T. whipplei DNA on CSF. After treatment the patient showed a mild clinical improvement although MR images and laboratory test remained unchanged. The MRS findings suggest that the pathological process of the disease diffusely involves the brain. Despite the absence of gastrointestinal involvement WD should be suspected in all complex and atypical neurological pictures, even in presence of peripheral involvement, in order to be able to start treatment promptly.

Erdheim-Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis of unknown origin characterized by systemic infiltrates of non-Langerhans histiocytes, usually involving multiple organs, including CNS.1–3 Skeletal involvement is considered highly specific and typical radionuclide bone scan findings include bilateral, symmetric increased tracer uptake in the metaphyses and diaphyses of the long bones, mainly femur and tibiae, with epiphyseal sparing.3 Once suspected in the living patient, the diagnosis of ECD needs to be confirmed by surgical biopsy of the affected tissues. Clinical manifestations are protean4 and in cases with neurologic involvement MRI can help diagnosis.5 We report 2 cases of adult-onset ECD with neurologic involvement and strikingly similar brain MRI pattern of abnormalities. ### Case 1. A 65-year-old man was admitted with a 4-year history of progressive loss of coordination and balance. He had had central diabetes insipidus for 3 years. Neurologic examination showed cerebellar ataxia and pyramidal signs. Dysarthria and dysphagia were also present, suggesting possible supranuclear bulbar involvement. Sensory, cognitive functions, and cranial nerves were normal. Biochemical parameters, including serum sodium, potassium, magnesium, and phosphate levels, were normal. A brain MRI showed diffuse hyperintensity in the pons extending to the left middle cerebellar peduncle and lower midbrain (figure, A). Diffuse hyperintensity of the periventricular white matter and thickening of the pituitary stalk were also evident. Bone radiographs showed bilateral, symmetric …

Despite intensive neurophysiological research, evidence is lacking to show whether abnormal cortical excitability in migraine reflects a primary cortical disturbance or reduced control by thalamo-cortical loops. One way to contribute to the scientific discussion on this topic is to deliver transcranial magnetic stimulation (TMS) and test the cortical silent period (SP) recorded in facial muscles. The facial-muscle SP is a purely cortical phenomenon that reflects the excitability of inhibitory interneurons, and can disclose changes in cortical inhibition even in patients without documented primary lesions of the motor cortices. To test the interictal excitability of cortical motor inhibitory interneurons in migraine, we investigated the facial-SP in patients with migraine with and without aura between attacks. In 26 patients and 15 age-matched controls, high-intensity magnetic stimuli were delivered with a round coil centered at the vertex during a maximal muscle contraction. Electromyographic responses were recorded from surface electrodes placed over the subjects' perioral muscles. Facial SPs were significantly shorter in patients than in controls. The SP shortening provides neurophysiological evidence showing hypoexcitability of cortical inhibitory neurons in patients with migraine between attacks. Despite a possible primary deficit of cortical inhibitory interneurons in migraine, we favor the interpretation of a secondary disfacilitation by hypoactive thalamo-cortical loops. Based on this interpretation, the interictal reduced cortical inhibition documented by the shortened SP could be considered the motor counterpart of the reduced preactivation excitability level in the sensory cortices purported to explain why cortical evoked responses habituate poorly in patients with migraine.

Familial hemiplegic migraine (FHM) is a rare subtype of migraine with aura with an autosomal dominant pattern of inheritance. Six FHM families underwent extensive clinical and genetic investigation. The authors identified a novel ATP1A2 mutation (E700K) in three patients from one family. In the patients, attacks were triggered by several factors including minor head trauma. In one subject a 3-day coma developed after a cerebral angiography. Overall, the phenotype of the patients closely resembles that of previously reported cases of FHM type II. The E700K variant might be regarded as the cause of the disease in this family, but this was not tested functionally.

Purpose The use of inferior alveolar nerve somatosensory evoked potentials may represent an objective means of evaluating sensory nerve function in the maxillofacial region. The aim of this work was to confirm the existence of a standard sequence of prominent events in the trigeminal somatosensory evoked potentials (TSEPs) of inferior alveolar nerve (IAN) waveform, examine those components and their normal variability by statistical analysis, and discuss TSEPs’ nervous origin and some patterns of TSEPs’ abnormalities due to dysfunctional nerves. Materials and Methods TSEPs were obtained following electrical stimulation (square wave pulses 0.2 millisecond [ms] in duration, 4 to 6.5 mA, 0.7/second repetition rate, 200 averages) of the gum at the mental foramen level via intraoral surface electrodes and recorded from the contralateral central scalp sites. Results We successfully recognized steady waveforms of sufficient quality and consistently recorded a “W”-shaped response: latency onset and peak of the initial deflection of positive polarity were approximately 12 ms and 20 ms, respectively. Negative and positive deflections followed with respective peak latencies at around 26 ms and 36 ms. One side of the lower lip can be compared with the contralateral side and patients may serve as their own control in cases of unilateral nerve injury. The anaesthetic block showed the total abolition of responses. Reproducible TSEP waveform was only obtained during nerve stimulation and not during masseter muscle stimulation. Conclusions TSEPs, obtained with the present technique, may represent an objective, low-invasive, and reliable way of testing sensory nerve function in the maxillofacial region.

A rapidly progressing dementia, followed by focal neurological signs, and evidence of periodic sharp wave complexes (PSWC) in the EEG may lead to the clinical suspicion of Creutzfeldt–Jakob disease (CJD). Different clinical variants of CJD have been described in the past, with prominent extrapyramidal or occipital lobe involvement, all included in the sporadic form of CJD (sCJD). Familiar and iatrogenic forms of CJD are also known. More recently a new variant has been described, vCJD [1], casually linked to bovine spongiform encephalopathy (BSE) and it has attracted increasing attention toward each form of rapidly progressing dementia; likewise the differential diagnosis between sCJD vs. vCJD is not always easy. Magnetic resonance imaging (MRI) too seems to have a peculiar role in differentiating sCJD from vCJD, even if the role of MRI in the diagnosis of CJD is still debated. Diffusion MRI is expected to play an important role in the clinical setting of CJD, contributing to formulation of an early diagnosis, especially in cases with unusual clinical presentation. In fact, the sensitivity of diffusion MRI is superior to that of conventional MRI (T1, T2, FLAIR) in detecting specific basal ganglia and cortical abnormalities early in the course of CJD [2] and these abnormalities correlate well with areas of the most severe and characteristic neuropathological changes [3]. We describe a case of autopsy–proven sCJD, with an unusual clinical course without dementia as a presenting symptom and discuss the role of diffusion MRI and laboratory tests in making an early diagnosis.

Intracortical facilitation and inhibition, as assessed by the paired-pulse transcranial magnetic stimulation technique with a subthreshold conditioning pulse followed by a suprathreshold test pulse, was studied upon awakening from REM and slow-wave sleep (SWS). Ten normal subjects were studied for four consecutive nights. Intracortical facilitation and inhibition were assessed upon awakening from SWS and REM sleep, and during a presleep baseline. Independently of sleep stage at awakening, intracortical inhibition was found at 1-3-ms interstimulus intervals and facilitation at 7-15-ms interstimulus intervals. Motor thresholds were higher in SWS awakenings, with no differences between REM awakenings and wakefulness, while motor evoked potential amplitude to unconditioned stimuli decreased upon REM awakening as compared to the other conditions. REM sleep awakenings showed a significant increase of intracortical facilitation at 10 and 15 ms, while intracortical inhibition was not affected by sleep stage at awakening. While the dissociation between motor thresholds and motor evoked potential amplitudes could be explained by the different excitability of the corticospinal system during SWS and REM sleep, the heightened cortical facilitation upon awakening from REM sleep points to a cortical motor activation during this stage.

Transcranial magnetic stimulation (TMS) of the motor cortex of one hemisphere (conditioning stimulus (CS)) inhibits EMG responses evoked in distal hand muscles by a later magnetic stimulus given at an appropriate interval, over the opposite hemisphere (test stimulus (TS)). This effect is commonly attributed to an inhibition produced at cortical level via a transcallosal route. The present study assessed the reproducibility of the transcallosal inhibition effects in different sessions in healthy subjects. Within- and between-subject variability, relating to interhemispheric differences was also evaluated. A magnetic CS on one hemisphere effectively inhibited EMG responses of the abductor digiti minimi stimulated by a TS delivered over the opposite hemisphere in a range of intervals centered at 12 ms. Even though group effects were reproduced in separate sessions, the high between- and within-subject variability yielded low test-retest correlations. This differentiation forces the definition of reproducibility (or repeatability), as the replication of the same mean curves of EMG reduction, and of reliability, as the between- or within-subject correlations between values of specific EMG measures. © 2003 Elsevier Science Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Publisher Summary The primary sensorimotor and adjacent brain areas following a vascular insult undergo remarkable neuroplastic changes, mainly within the affected hemisphere (AH), but also in the unaffected hemisphere (UH). When the damage affects the core of the sensorimotor areas, reorganization is crucial for functional recovery; meanwhile, reorganization outside the usual boundaries never reaches the same functional efficiency of the original circuits. Interhemispheric asymmetries were more frequently encountered in the “subcortical” than in the “cortical” type of lesions. It is noteworthy that larger than normal amplitudes of somatosensory evoked responses with an asymmetrical waveshape were found frequently from the AH, especially following a cortical lesion. A somewhat similar pattern of abnormality is seen in patients showing larger than normal motor evoked potentials (MEPs) during transcranial magnetic stimulation (TMS) of the UH; this is usually combined with absent response from the AH and was a bad prognostic index. The functional reorganization of the motor output following a hemispheric stroke has been repeatedly reported, often with an excessive asymmetry of the sensorimotor hand topography between the AH and the UH. “Map migration” is usually on the medio-lateral axis, but an anteroposterior shift of up to several mms of the map's center of gravity has also been observed.

Summary Recovery of function after a stroke is attributable to several factors, including events in the first few days (eg, reabsorption of perilesional oedema, tissue reperfusion). However, consistent reorganisation and recovery after a stroke takes weeks or months. In the early stages, recovery from stroke can vary greatly among patients with identical clinical symptoms. Neuroimaging techniques that enable us to assess baseline and task‐related functions, and neurophysiological techniques that measure brain function in "real time", can be used to study the recovery of brain lesions after a stroke. In this review, we discuss important neuroimaging and neurophysiological studies of post‐stroke brain reorganisation.

Objective : To evaluate the usefulness, sensitivity and specificity of a new neurophysiological test for partial conduction block. Methods . In 17 patients (17 nerves) with clinical pictures strongly suggesting the presence of motor conduction block and 20 healthy subjects (40 nerves), motor nerve conduction studies were performed with the conventional surface technique and with a new technique developed by us: the single fiber EMG (SFEMG) conduction block test. Moreover, we also evaluated patients with other neurological diseases. The recent American Association of Electrodiagnostic Medicine (AAEM) consensus criteria for partial conduction block were used for the standard conduction block tests. Results : According to AAEM consensus criteria, 5/17 cases presented ‘definite' partial conduction block and 6 presented ‘probable' partial conduction block. In contrast, 16/17 cases (94%) presented evidence of conduction block at the SFEMG conduction block test. The 5/6 cases that did not fulfill in the AAEM criteria and that presented abnormal findings at SFEMG nerve conduction test could be considered affected by minimal conduction block. The sensitivity of this new test was greater than conventional test. The specificity was 100% (no abnormal findings in healthy subjects or patients with diseases other than neuropathy). Conclusions : The SFEMG conduction block test is a sensitive, complementary, technique for diagnosis of minimal conduction block in patients with normal findings in standard nerve conduction studies.

To assess the relationship between peripheral nerve involvement and the patient’s perception of his own quality of life, we studied 36 consecutive out-patients affected by insulin-dependent diabetes mellitus without other diabetic complications other than neuropathy (20 men, 16 women; mean age 39.1 years). We used clinical (Semmes-Weinstein, vibration perception threshold, muscle strength, osteotendinous reflexes), neurophysiological (sural, peroneal and ulnar nerves), metabolic (glycosylated haemoglobin) and patient-oriented (SF-36 and NASS questionnaires) measurements. Patient-oriented physical scores were significantly related to: (1) neurophysiological findings of the inferior limbs; (2) conventional measurements of sensitivity; (3) metabolic assessment. Conversely, patient-oriented mental scores were significantly related only to metabolic assessment. The patient-oriented measure provided an important perspective of the severity of the disease often closely related with the biological parameters and suggested new ways of interpreting conventional biological measurements. In particular, the peripheral nerve picture appeared strictly related with the physical aspects of the patients’ quality of life, while the metabolic picture appeared related with both the mental and physical aspects of the quality of life.

We examined the relationships between diabetic peripheral nerve involvement and patients' own perception of quality of life in a multidimensional study based on outcome research recommendations. The study enrolled 50 consecutive outpatients with type 1 diabetes mellitus (23 men, 27 women; mean age, 40.1 years). The patients were evaluated with validated clinical tests (e. g. Semmes-Weinstein, vibration perception threshold, muscle strength), neurophysiological tests (sural, peroneal and ulnar nerves) and patient-oriented (SF-36 and NASS) questionnaires. Patient-oriented physical scores were significantly related with: (1) neurophysiological findings of the lower limbs; (2) conventional measurements of sensitivity. Conversely, patient-oriented mental scores were not related with these findings. The patient-oriented questionnaires provided an important perspective of the severity of the disease, often closely related with the biological parameters. They offered new interpretations to conventional biological measurements. In particular, the peripheral nerve picture was strictly related to the physical aspects of the patients' quality of life, and not with the mental aspects.

The potential for reorganization in the adult brain has been largely underestimated in the past and we are just beginning to understand the organisational principles involved in functional recovery. A bulk of experimental evidences have been accumulated in support of the hypothesis that neuronal aggregates adjacent to a lesion in the cortical brain areas can be progressively vicarious to the function of the damaged neurones. Such a reorganisation, if occurring in the affected hemisphere of a patient with a monohemispheric lesion, should significantly modify the interhemispheric symmetry of somatotopic organisation of the sensorimotor cortices, both in terms of absolute surfaces and number of "recruited" neurons, as well as of spatial coordinates. In fact, a roughly symmetrical organisation of sensorimotor - particularly for the hand contorl - in the right and left hemisphere has been observed in healthy humans by different methods of functional brain imaging, including fMRI, TMS, MEG, HD-EEG. Not uniform results about the functional brain activity related to sensory, motor and cognitive functions in normal and diseased subjects are often due to differences in the experimental paradigm designed as well as in the spatial and temporal resolution of the neuroimaging techniques used. The multi-modal integration of data obtained with several neuroimaging techniques allowed a coherent modelling of human brain higher functions. Functional magnetic resonance imaging (fMRI) provided fine spatial details (millimetres) of the brain responses, which were compared with the cortical maps of the motor output to different body districts obtained with transcranial magnetic stimulation (TMS). Magnetoencephalography (MEG) ability to study sensorimotor areas by analysing cortical magnetic fields, is also complementary to the motor cortex topographical mapping provided by TMS. MEG high temporal resolution allows to detect relatively restricted functional neuronal pools activated during cerebral processing of external stimuli. Moreover, these brain responses can be investigated with magnetoencephalography (MEG) and high density electroencephalography (EEG) techniques, with elevated time resolution (ms). With respect to the high resolution EEG technique, the MEG technique allowed a more precise localisation of the sites of neural activity buried into the cortical sulci, but was unable to detect the response of the crown of the cortical giri and of the frontal-mesial cortex (including the supplementary motor area), because of its poor sensitivity to radially oriented dipoles. The integration of functional and anatomical information provide cues on the relationship between brain activity and anatomic sites where this takes place, allowing the characterisation of the physiological activity of the cortical brain layers as well as to study the plastic reorganisation of the brain in different pathological conditions following stroke, limb amputation, spinal cord injury, hemisperectomy.

Objective : The aim of this study was to verify the action of Botulinum toxin type-A (BoNT-A) by means of neurophysiological techniques, in patients presenting lower limb spasticity and requiring BoNT-A injections in the calf muscles, due to the poor response to medical antispastic treatment. Subjects and method : Patients presenting paraparesis were enrolled. They underwent clinical evaluation for spasticity according to the Ashworth scale and neurophysiological recordings including: motor evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) of the leg area; compound motor action potential (cMAP) to tibial nerve stimulation, F-wave, and H-reflex before the treatment and 24 h, 2 weeks and 1 month after the injection of BoNT-A. In all patients, gastrocnemius was treated and in some cases soleus or tibialis posterior muscles were also injected. Results : In all patients, BoNT-A injections induced a clear clinical improvement as showed by the reduced spasticity values of the Ashworth scale. A significant increment of MEP latency and central conduction time (CCT) duration were observed 2 weeks after the treatment only in the injected muscles. Conclusions : Prolonged MEP latencies and CCT after BoNT-A injections is probably due to a central alteration in responsiveness of spinal motor neurons to descending impulses from the corticospinal tracts. Such changes represent objective parameters heralding clinical efficacy of treatment.

We simultaneously performed near infrared spectroscopy (NIRS) and transcranial Doppler (TCD) to evaluate the effects of hypercapnia as well as of scalp ischemia on the blood flow at two different depth levels within the brain and of the scalp vessels. A decrease in the backscattered light intensity, meaning an increment of blood volume, was detected at the end of hypercapnia in all healthy subjects. This decrement was partly masked by ischemia in the cutaneous vessels. In 2 patients with a monohemispheric lesion in the middle cerebral artery (MCA) territory, an increase in NIRS response was found in the healthy hemisphere, while in the stroke side the CO2-induced changes were negligible. TCD data showed a similar increment of blood flow velocity to the hypercapnia in both hemispheres, with no differences between the affected and normal side in 1 patient, whereas in the second one, no increment was observed on the affected side, probably due to internal carotid artery stenosis. The two methods nicely integrate: TCD mainly tests subcortical changes in the MCA flow, while NIRS is exquisitely sensitive to cortical arterioles and capillary blood flow modifications.

Motor evoked potentials (MEPs) to magnetic transcranial stimulation (TCS) were simultaneously and bilaterally recorded from flexor carpi radialis (FCR) and extensor communis digitorum (ECD) muscles in seven healthy and trained subjects. Latencies and amplitudes characteristics of MEPs were investigated under the following randomised conditions: muscular and mental relaxation; mental simulation, during absolute muscular relaxation, selective flexion or extension of the right or left wrist muscles; arithmetical calculation with muscular relaxation. Unspecific, diffuse facilitatory effects on MEPs amplitude were induced by mental non motor activity (arithmetical calculation). A further specific and lateralised amplitude potentiation on the agonist muscle acting as 'prime mover' for the mentally simulated movement was consistently found in all the subjects, without significant latency changes. Inhibitory effects on antagonists were evident only in two subjects.

The effects of hypercapnia on the intensity and phase of near infrared light back-scattered by the head were studied on eight healthy humans and two patients affected by monohemispheric lesions in the Middle Cerebral Artery (MCA) territory. A decrease in the light intensity and a variation of the phase were detected in all healthy subjects during apnea and hypercapnia. Only negligible changes were observed in the affected hemisphere of the patients. A concomitant study by Transcranial Doppler Sonography (TCD) showed an increase of the blood flow during hypercapnia both in normal hemispheres and, to a less extent, in the affected hemisphere of patients. This suggests that NIRS (Near Infrared Spectroscopy) is more sensitive to alterations of more cortical brain vascular system than TCD which is mainly testing MCA in the depth.

Background and purpose The thalamus seems to be profoundly involved in the cyclical recurrence of migraine clinical and neurophysiological features. Here possible structural changes in the thalamus of migraineurs were searched for by means of diffusion tensor (DT) magnetic resonance imaging (MRI). This MRI technique provides quantitative data on water molecule motion as a marker of tissue microstructure. Methods Twenty-four untreated migraine without aura (MO) patients underwent DT-MRI scans (3-T Siemens Gyroscan) during (n = 10) and between attacks (n = 14) and were compared with a group of 15 healthy volunteers (HVs). Fractional anisotropy (FA) and mean diffusivity (MD) were examined. Results During the interictal phase MO patients had a significantly higher FA and slightly lower MD values in bilateral thalami compared with HVs. During attacks, all MRI quantitative measurements in migraineurs were similar to those found in HVs. Right thalamic FA was positively correlated with the number of days since the last migraine attack in pooled patient data (r = 0.626, P = 0.003). Conclusions These higher thalamic FA values noted during the interictal period which normalized during an attack are probably related to plastic peri-ictal modifications in regional branching and crossing of fibres. Whether these changes could be considered as the anatomical counterpart of the cyclical functional fluctuations previously observed in the neurophysiology of migraine remains to be determined.

We report a mentally retarded 30-year-old woman with partial trisomy of chromosome 9 (46, XX-6, +der(6)t(6,9)pat) who has had epilepsy since age 11 months. She had been treated with various combinations of drugs. After 1 year of treatment with valproate (VPA) and ethosuximide (ESM), the patient developed arthralgias, muscle weakness, fatigue, and fever. Laboratory examination showed increased sedimentation rate, hypergammaglobulinemia, and high titers of antinuclear antibodies (ANA). The possibility of VPA-induced systemic lupus erythematosus (SLE) was considered. This diagnosis was supported by detection of antihistone antibodies and the HLA-DR4 antigen. VPA dosage was tapered and discontinued, with accompanying resolution of clinical, immunological and hematological signs of SLE 6 weeks after VPA discontinuation. This is the fourth reported case of VPA-induced SLE.

Background and objectives Studies of spontaneous EEG and visual or somatosensory evoked high frequency oscillations indicate that the abnormal fluctuations of cortical responsivity over time in relation to the migraine attack could be due to abnormal thalamic control. Here we searched for possible structural changes in the thalamus of migraineurs by mean of acquiring diffusion tensor magnetic resonance imaging (MRI). This MRI technique provides quantitative data on water molecular motion, as a marker of tissue structure. Materials & Method – Seventeen untreated migraine without aura (MO) patients underwent MRI scan (3-Tesla Siemens Gyroscan) during (n=7) and between attacks (n=10) and were compared to a group of 14 healthy volunteers (HV). We examined fractional anisotropy (FA) and mean diffusivity (MD) in the thalamus.

We studied retrospectively the intraoperative preresection electrocorticograms (ECoGs) of 72 patients undergoing surgery for medically intractable, mostly complex partial, temporal lobe seizures (TLS). Quantification of interictal epileptiform discharges (EDs) detected visually at each electrode location in 2 min recording epochs included computations of ED rates (EDs/min) and cumulative voltages (CuVs) (μV/min). Of 6388 EDs, 81% involved the infratemporal surface, 18% the lateral temporal surface and 1% the orbital frontal area. Forty-eight patients (67%) demonstrated multiple (up to 5 or more), temporally independent foci. Dominant foci in medial and lateral infratemporal locations were about equally common and were significantly more frequent than in lateral temporal locations. Rankings of ED CuVs and rates at individual cortical locations defined 4 areas of “relative interictal cortical epileptogenicity.” These were arranged in an orderly pattern with the anterior parahippocampal gyrus and the inferomedial surface of the temporal tip displaying the highest and the lateral temporal and posterior infratemporal cortices showing the lowest propensity to the interictal epileptiform discharge. Individual areas were not characterized by distinct clinical seizure manifestations. Preresection ECoGs provide information on the epileptogenic dysfunction that involves most of the temporal lobe of patients with medically intractable TLS.

A patient affected by familial hemiplegic migraine underwent Transcranial Doppler Sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headache-free period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. Our results indicate that during the attack in this familial hemiplegic migraine patient a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, Transcranial Doppler Sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome.

BackgroundPrevious studies with Transcranial Magnetic Stimulation (TMS) have focused on the cortical representation of limited group of muscles. No attempts have been carried out so far to get simultaneous recordings from hand, forearm and arm with TMS in order to disentangle a 'functional' map providing information on the rules orchestrating muscle coupling and overlap. The aim of the present study is to disentangle functional associations between 12 upper limb muscles using two measures: cortical overlapping and cortical covariation of each pair of muscles. Interhemispheric differences and the influence of posture were evaluated as well.Methodology/principal findingsTMS mapping studies of 12 muscles belonging to hand, forearm and arm were performed. Findings demonstrate significant differences between the 66 pairs of muscles in terms of cortical overlapping: extremely high for hand-forearm muscles and very low for arm vs hand/forearm muscles. When right and left hemispheres were compared, overlapping between all possible pairs of muscles in the left hemisphere (62.5%) was significantly higher than in the right one (53.5% ). The arm/hand posture influenced both measures of cortical association, the effect of Position being significant [p = .021] on overlapping, resulting in 59.5% with prone vs 53.2% with supine hand, but only for pairs of muscles belonging to hand and forearm, while no changes occurred in the overlapping of proximal muscles with those of more distal districts.Conclusions/significanceLarger overlapping in the left hemisphere could be related to its lifetime higher training of all twelve muscles studied with respect to the right hemisphere, resulting in larger intra-cortical connectivity within primary motor cortex. Altogether, findings with prone hand might be ascribed to mechanisms facilitating coupling of muscles for object grasping and lifting -with more proximal involvement for joint stabilization- compared to supine hand facilitating actions like catching. TMS multiple-muscle mapping studies permit a better understanding of motor control and 'plastic' reorganization of motor system.

Background Recent evidence indicates that peripheral tissue markers can provide information regarding changes affecting cellular metabolism in Alzheimer disease (AD). We previously reported that serum copper levels can discriminate subjects with AD from normal control subjects (with 60% sensitivity and 95% specificity) and from patients with vascular dementia (with 63% sensitivity and 85% specificity). Objective To study the correlation between AD and serum levels of transition metals and markers of peripheral oxidative stress. Design Case study. Setting General hospital inpatient wards and outpatient clinics. Patients A pair of elderly monozygotic female twins discordant for AD. Main Outcome Measures Biochemical analyses of peripheral-blood transition metals and indicators of oxidative stress and neurologic and neuropsychological assessments of clinical status for presence of cognitive impairment and AD. Results Serum copper and total peroxide levels were both 44% higher in the twin with greater cognitive impairment and a diagnosis of AD. Conclusions The cases reported support the hypothesis of a major involvement of copper and oxidative abnormalities in AD.