Rhythmic cortical myoclonus in patients with 6Q22.1 deletion.

DNA deletions involving 6q22.1 region result in developmental encephalopathy (DE), often associated with movement disorders and epilepsy. The phenotype is attributed to the loss of the NUS1 gene included in the deleted region. Here we report three patients with 6q22.1 deletions of variable length all showing developmental delay, and rhythmic cortical myoclonus. Two patients had generalized seizures beginning in infancy. Myoclonic jerks had polygraphic features consistent with a cortical origin, also supported by cortico-muscular coherence analysis displaying a significant peak around 20 Hz contralateral to activated segment. Deletions in 6q22.1 region, similarly to NUS1 loss-of-function mutations, give rise to DE and cortical myoclonus via a haploinsufficiency mechanism. A phenotype of progressive myoclonic epilepsy (PME) may also occur.

Impaired Visual Inhibition in Amnestic Mild Cognitive Impairment.

Objective.The pathophysiology of amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD) is still a matter of debate. Visual system might be precociously altered, especially for its cholinergic connections. We thus studied patients with aMCI compared to AD with paired-pulse flash-visual evoked potentials (paired-F-VEPs), a putative marker of cholinergic function. Methods. We enrolled 12 adult patients with aMCI and 12 with AD. 14 normal age- and sex-matched subjects acted as controls (HS). Stimuli were single flashes, with interspersed random flash pairs at critical interstimulus intervals (ISIs, 16.5 to 125 ms) with closed eyes. The "single" (unconditioned) F-VEP was split into a "main complex" (50 to 200 ms after the flash) and a "late response" (200 to 400 ms). As for paired stimulation, the "test" F-VEP emerged from electronic subtraction of the "single" F-VEP from the "paired"-F-VEP. Results. In the single F-VEP, P2 latency was prolonged in patients (aMCI and AD) compared to HS (p < .05). As to the paired F-VEPs, in aMCI the "late response" normal inhibition was abolished at ISIs 50-62.5 ms (p ≤ .016), compared to AD and controls. No changes were detected for the "main complex". Conclusions. Paired-F-VEPs demonstrate a defective neural inhibition in the visual system of patients with aMCI at critical intervals. It may represent a compensatory mechanism against neuronal loss, the failure of which may be involved in AD development. Paired-F-VEPs may warrant inclusion in future preclinical/clinical studies, to evaluate its potential role in the pathophysiology and management of aMCI.

Neurological emergency at the COVID-19 pandemic: report from a referral hospital in Eastern Piedmont, Italy.

BACKGROUND: The pandemic implied dramatic changes in public health assets. In Italy, some Stroke Units were transformed into sub-intensive COVID-19 Units, making the management of neurological patients demanding. We described how the flow of neurological emergencies was affected by the pandemic impact. METHODS: We analyzed accesses to the Emergency Department (ED) of the "Maggiore della Carità" Hospital, Piedmont, Italy, during a period of 8 months (COVID time; March to May 2020 and October 2020 to February 2021) and analyzed the admissions to the Neurology Unit and the underlying diagnosis. We also evaluated potential changes in the treatment of acute ischemic stroke in the same period. These variables were compared with two equivalent periods of time (2019-2020; 2018-2019). RESULTS: During the COVID time, there was a clear-cut reduction of the total ED accesses compared to NoCOVID times. However, admissions for acute neurological conditions showed a mild but non-significant decrease (6.3%vs.7.3%). The same applied to acute ischemic stroke, which represented the most common condition (47.7%). The proportion of patients who underwent emergent reperfusion therapies remained unchanged. Furthermore, no difference was found in door-to-needle and door-to-groin intervals between COVID time and NoCOVID times. On the contrary, the onset-to-door interval was significantly longer during the COVID time (p value: 0.001). DISCUSSION: While the percentage of admissions following an ED access grew dramatically, those to the Neurology Unit showed overall only a slight non-significant decrease. This finding implicitly reflects the serious and urgent nature of many neurological diseases, compelling people to access EDs at any time.

Predictive factors of Status Epilepticus and its recurrence in patients with adult-onset seizures: A multicenter, long follow-up cohort study.

PURPOSE: Status epilepticus (SE) is associated with high morbidity and mortality. This multicenter retrospective cohort study aims to identify the factors associated with the occurrence of SE and the predictors of its recurrence in patients with adult-onset seizures. METHODS: We retrospectively analyzed data of 1115 patients with seizure onset>18 years, observed from 1983 to 2020 in 7 Italian Centers (median follow-up 2.1 years). Data were collected from the databases of the Centers. Patients with SE were consecutively recruited, and patients without SE history were randomly selected in a 2:1 ratio. To assess determinants of SE, different clinical-demographic variables were evaluated and included in univariate and multivariate logistic regression model. RESULTS: Three hundred forty-seven patients had a SE history, whereas the remaining 768 patients had either isolated seizures or epilepsy without SE history. The occurrence of SE was independently associated with increasing age at onset of disease (OR 1.02, 95% CI 1.01--1.03, p<0.001), female sex (OR 1.39, 95% CI 1.05--1.83, p=0.02) and known etiology (OR 3.58, 95% CI 2.61--4.93, p<0.001). SE recurred in 21% of patients with adult-onset SE and recurrence was associated with increasing number of anti-seizure medications taken at last follow-up (OR 1.88, 95% CI 1.31--2.71, p<0.001). CONCLUSIONS: In patients with adult-onset seizures, SE occurrence is associated with known etiologies, advanced age and female sex. Patients with recurrent SE are likely to have a refractory epilepsy, deserving careful treatment to prevent potentially fatal events.

Flash-evoked high-frequency EEG oscillations in photosensitive epilepsies.

OBJECTIVE: To determine the feasibility of measuring scalp-recorded, flash-evoked, high-frequency EEG oscillations (F-HFOs) using a relatively simple technique. Furthermore, to assess whether F-HFOs are enhanced in photosensitive epileptic patients and if they might be proposed as a putative non-provocative biomarker of photosensitivity. METHODS: We studied 19 photosensitive patients with idiopathic generalized epilepsy, and 22 controls matched for demographic features. We extracted F-HFOs from the broadband scalp flash-visual evoked potential (b F-VEP) through appropriate filtering. We measured F-HFO amplitude, number and latency. Also, we carried out a time-frequency domain spectral F-HFO analysis. Inter-group statistics was performed. Within-groups, F-HFO features were correlated to the b F-VEP. RESULTS: The N3-N3I wave of the b F-VEP was significantly (p = 0.01) larger in patients compared to controls. The same was true for the inter-group F-HFO amplitude (p = 0.01). F-HFOs showed two main spectral peaks (∼88 and ∼125 Hz), whose power was greater (p = 0.001) in patients than in controls. The ∼88 Hz peak power exceeded the upper normal range in 15/19 patients. Patients showed a significant (p = 0.04) correlation between the ∼88 Hz peak power and the size of the N3-N3I wave. SIGNIFICANCE: A simplified F-HFO measurement proved feasible. In patients, F-HFOs were enhanced in terms of both size and spectral power, suggesting a role in the generation of the photoparoxysmal response. Some spectral features of the F-HFOs may be proposed as a putative non-provocative marker of epileptic photosensitivity.

Direct antivirals and cognitive impairment in hepatitis C: a clinical-neurophysiologic study.

Cognition was assessed in hepatitis C virus (HCV) patients, who did not meet the criteria for a minimal hepatic encephalopathy. Their liver function was compensated. We then disentangled potential cognitive changes associated with a sustained virologic response at 12 weeks (SVR-12), following treatment with direct antiviral agents (DAAs). We studied 23 selected HCV patients with a battery of standard neuropsychological tests, and with recordings of the P300 wave, a cerebral potential of "cognitive" significance. There was a baseline evaluation (T0) and a second one 6 months later (T1). We had 2 control groups of comparable age and sex, i.e., 15 patients suffering from non-alcoholic fatty liver disease (NAFLD) and 15 healthy subjects. At T0, we detected a significant (p < 0.05) cognitive impairment in the HCV group, which involved episodic and working memory, attention, visuospatial and verbal abilities, executive functions, and logic reasoning. The P300 latency was significantly (p < 0.05) delayed in the group. At T1, we observed some significant (p < 0.05) HCV recovery in given test domains, e.g., memory, executive functions, and reasoning. Accordingly, the P300 latency shortened significantly (p < 0.05). HCV patients exhibited subtle cognitive defects, somehow independent of their liver condition, possibly linked to direct or indirect brain involvement by the virus. These defects partly recovered following the SVR-12, as achieved through DAAs. The P300 wave was a valid neurophysiologic counterpart of these changes. DAAs can have a role in the early preservation of cognition in HCVs.

Cannabinoids in multiple sclerosis: A neurophysiological analysis.

OBJECTIVES: To investigate the action of cannabinoids on spasticity and pain in secondary progressive multiple sclerosis, by means of neurophysiological indexes. MATERIAL AND METHODS: We assessed 15 patients with progressive MS (11 females) using clinical scales for spasticity and pain, as well as neurophysiological variables (H/M ratio, cutaneous silent period or CSP). Testing occurred before (T0) and during (T1) a standard treatment with an oral spray containing delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Neurophysiological measures at T0 were compared with those of 14 healthy controls of similar age and sex (HC). We then compared the patient results at the two time points (T1 vs T0). RESULTS: At T0, neurophysiological variables did not differ significantly between patients and controls. At T1, spasticity and pain scores improved, as detected by the Modified Ashworth Scale or MAS (P = .001), 9-Hole Peg Test or 9HPT (P = .018), numeric rating scale for spasticity or NRS (P = .001), and visual analogue scale for pain or VAS (P = .005). At the same time, the CSP was significantly prolonged (P = .001). CONCLUSIONS: The THC-CBD spray improved spasticity and pain in secondary progressive MS patients. The spray prolonged CSP duration, which appears a promising tool for assessing and monitoring the analgesic effects of THC-CBD in MS.

Cortical visuomotor interactions in Freezing of Gait: A TMS approach.

OBJECTIVES: Altered cortical visuomotor integration has been involved in the pathophysiology of freezing of gait (FoG) in parkinsonism. The aim of this study was to assess the connections between the primary visual (V1) and motor (M1) areas with a paired-pulse, twin-coil transcranial magnetic stimulation (TMS) technique in patients with FoG. METHODS: Twelve Parkinson's disease (PD) patients suffering from levodopa-responsive-FoG (off-FoG) were compared with 12 PD patients without FoG and 12 healthy subjects of similar age/sex. In the "off" condition, visuomotor connections (VMCs) were assessed bilaterally. A conditioning stimulus over the V1 phosphene hotspot was followed at interstimulus intervals (ISIs) of 18 and 40ms by a test stimulus over M1, to elicit motor evoked potentials (MEPs) in the contralateral first dorsal interosseous muscle. RESULTS: Significant (P<0.01), bilateral effects due to VMCs were detected in all three groups, consisting of a MEP suppression at ISI 18 and 40ms. However, in PD patients with FoG, the MEP suppression was significantly (P<0.05) enhanced, both at ISI 18-40ms, in comparison with the other two groups. The phenomenon was limited to the right hemisphere. CONCLUSIONS: PD patients with FoG showed an excessive inhibitory response of the right M1 to inputs travelling from V1 at given ISIs. Right-sided alterations of the cortical visuomotor integration may contribute to the pathophysiology of FoG.

Correction to: Villaret syndrome as clinical presentation of occult metastatic breast cancer.

The author's given name and family name were initially interchanged inadvertently. The correct names have been corrected above. The original article was corrected.

A patient with autoimmune limb-girdle myasthenia, and a brief review of this treatable condition.

Limb-girdle myasthenia gravis (LGM) is an uncommon clinical picture related to an antibody-mediated blockage of the neuromuscular junction. We describe a 44-year old man who presented with a proximal limbs' weakness that resembled a myopathic disorder. The repetitive nerve stimulation at 3Hz showing a decremental response suggested myasthenia, that was confirmed by the presence of an increased titer of anti-acetylcholine receptor antibodies (AChRAbs), and of hyperplastic foci at thymus histology. Symptomatic treatment with pyridostigmine was not effective, whereas the patient improved adding Azathioprine. In conclusion, a myopathic-like clinical picture in an adult could be caused by LMG. Thymus pathology, or (rarely) increased AChRAbs could support the diagnosis of LGM.

Auditory seizures in autoimmune epilepsy: a case with anti-thyroid antibodies.

In its classic presentation, Hashimoto's encephalopathy is an acute-subacute complex neuropsychiatric syndrome with cognitive impairment, hallucinations, myoclonus, tremor or ataxia, associated with elevated anti-thyroid antibodies. Corticoids and immunotherapy are dramatically effective. However, in some cases, not all the associated features are presented and this delays diagnosis and appropriate treatment. We describe a man with abrupt onset of recurrent auditory seizures resulting in refractory non-convulsive status epilepticus. The patient was diagnosed with an autoimmune encephalopathy with elevated serum and CSF anti-thyroid antibodies. None of the antiepileptic drugs were successful, however, following immune-modulating therapy, the refractory non-convulsive status epilepticus dramatically improved, as did the patient overall. We suggest that Hashimoto's encephalopathy should be suspected in otherwise healthy patients with unexplained new-onset focal recurrent auditory seizures which do not respond to antiepileptic drugs. The presence of anti-thyroid antibodies in the CSF supports this diagnosis.

Overactive visuomotor connections underlie the photoparoxysmal response. A TMS study.

OBJECTIVE: The photoparoxysmal response (PPR) involves rapid spread of epileptic activity from visual to parietal and frontal areas. We used a transcranial magnetic stimulation (TMS) technique to assess the physiologic connections between primary visual (V1) and motor (M1) areas in patients with idiopathic generalized epilepsy (IGE). We hypothesized that in PPR-positive patients, M1 would respond excessively to inputs from V1. METHODS: Eleven photosensitive patients with IGE who had a PPR at the time of the study were compared with 10 similar patients without a PPR, and with 11 healthy subjects of similar age and sex. The connection between V1 and M1 was assessed in resting participants by delivering a conditioning stimulus (CS) over the phosphene hotspot of the visual cortex (intensity 90% phosphene threshold, PT) followed at random interstimulus intervals (ISIs; 15, 18, 21, 24, 27, 30, 35 and 40 msec) by a test stimulus (TS) over the left motor cortex to elicit a motor evoked potential (MEP) of ~1 mV from the right first dorsal interosseous muscle. RESULTS: In healthy subjects, a CS over V1 suppressed M1 at ISIs between 18 and 40 msec. Similar effects occurred in IGE patients without a PPR. This was not true in PPR-positive IGE patients, in whom this type of physiologic inhibition was significantly (p < 0.05) reduced. SIGNIFICANCE: IGE patients with a PPR have an overactive functional response of M1 to inputs traveling from V1. This may represent one core factor for the anterior spread of the PPR itself and for the origin of the abnormal epileptic motor phenomenon, such as myoclonus.

Abnormal motor cortex plasticity in juvenile myoclonic epilepsy.

PURPOSE: Abnormal cortical plasticity has been hypothesized to play a crucial role in the pathogenesis of juvenile myoclonic epilepsy (JME). To study the motor cortical plasticity we used paired associative stimulation (PAS). When a repetitive electrical stimulus to the median nerve is paired with a transcranial magnetic stimulus (TMS) pulse over the controlateral motor cortex with at an interstimulus interval (ISI) of 21.5-25ms, a long term potentiation (LTP)-like synaptic plasticity is induced in the corticospinal system. Aim of this study was to investigate the motor cortex LTP-like synaptic plasticity by means of PAS in patients with JME. METHODS: Twelve adult patients with JME were compared with 13 healthy subjects of similar age and sex. PAS consisted of 180 electrical stimuli of the right median nerve paired with a single TMS over the hotspot of right abductor pollicis brevis (APB) at an ISI of 25ms (PAS25). We measured motor evoked potentials (MEPs) before and after each intervention for up to 30min. RESULTS: In healthy subjects the PAS25 protocol was followed by a significant increase of the MEP amplitude (p<0.001). On the contrary, in patients with JME, the MEP amplitude did not change. CONCLUSION: Defective motor cortex plasticity is likely involved in the pathogenesis of JME.

Impaired visual inhibition in migraine with aura.

OBJECTIVE: The pathophysiology of migraine with or without aura (MA, MO) is still a matter of debate. We thus studied patients with MA and MO by means of paired-pulse flash-visual evoked potentials (paired F-VEPs). This technique, recently revived, analyses the overall excitability of visual system as detected from the cortical occipital signal. METHODS: We enrolled 13 adult patients with MO and 13 with MA. Twenty-two normal subjects of similar age and sex acted as controls. Stimuli were single flashes, intermingled at random to flash pairs at critical interstimulus intervals (ISIs, 16.5-125ms) with closed and open eyes. The "single"(unconditioned) F-VEP was split into a "main complex" (50-200ms after the flash) and a "late response" (200-400ms). As for paired stimulation, the "test" F-VEP emerged from electronic subtraction of the "single" F-VEP to the "paired" F-VEP. Its size was expressed as "test"/"single"F-VEP∗100. RESULTS: As for paired F-VEPs, the "main complex" of the "test" F-VEP in the MA group did not show the size reduction (at ISIs 50-62.5ms) which was typical among the control and MO groups (p⩽0.016) in the "eyes-closed" state. CONCLUSIONS: Paired F-VEPs document a defective neural inhibition in the visual system of patients with MA. SIGNIFICANCE: Paired F-VEPs may warrant inclusion in future preclinical/clinical studies, to evaluate its potential role in the pathophysiology and management of MA.

Interictal ghrelin levels in adult patients with epilepsy.

PURPOSE: In vitro or in animal models of epilepsy, ghrelin showed a clear anticonvulsant action, whose mechanisms are somewhat obscure. In humans however, a controversial relation exists between ghrelin and epilepsy. Yet most studies investigated just total ghrelin levels, without a proper distinction between acylated (AG) or unacylated ghrelin (UAG). We thus evaluated separately AG and UAG interictal levels in adult patients with epilepsy, and their relation to clinical features. METHOD: Cross-sectional study in a tertiary referral centre. Fifty-six patients were recruited: 19 with idiopathic generalized epilepsy, 18 with cryptogenic focal epilepsy and 19 with symptomatic focal epilepsy. Twenty-six healthy subjects of similar age, sex and body mass index (BMI) acted as controls. AG and UAG levels were measured following an overnight fasting and contrasted to the clinical and biometric features. RESULTS: AG and UAG levels were similar between patients and controls. The AG/UAG ratio was higher in patients, also when weighted for covariates (age, BMI, gender, and drugs). Splitting patients according to their epileptic syndrome, drug-resistance or antiepileptic drug number/type resulted in no significant difference in AG, UAG or their ratio. Yet, AG and UAG levels were positively predicted by disease duration, independently by confounders. CONCLUSION: In adult patients with epilepsy, interictal ghrelin levels did not differ from controls, though the AG/UAG ratio was imbalanced. Interpretation of the latter phenomenon is uncertain. Further, levels of AG and UAG were in direct proportion to disease duration, which may represent a long-term compensatory mechanism, antagonistic to the epileptic process.

Peroneal nerve involvement as initial manifestation of primary systemic vasculitis.

We report a case of two patients with foot drop due to peroneal nerve infarct as early sign of two different forms of primary systemic vasculitides: a predominantly small-vessel p-antineutrophil cytoplasmic antibody-positive vasculitis (microscopic polyangiitis) and a predominantly medium-vessel vasculitis (polyarteritis nodosa).

Defective visual inhibition in photosensitive idiopathic generalized epilepsy.

PURPOSE: To assess the visual system excitability of photosensitive patients with idiopathic generalized epilepsy (IGE) with the paired-pulse flash-evoked potential (paired F-VEP) technique. METHODS: We studied 19 photosensitive patients with IGE (16 women) showing a photoparoxysmal electroencephalographic (EEG) response (PPR). Twenty-two normal subjects of similar age and sex acted as controls (17 women). We recorded F-VEPs from occipital and central electrodes. Stimuli were single flashes, intermingled to flash pairs at the interstimulus interval (ISI) of 333, 125, 62.5, 50, 33, and 16.5 msec (i.e., at the internal frequency of 3, 8, 16, 20, 30, and 60 Hz). Recordings were done both with closed and open eyes. The single F-VEP was split into a "main complex" and a "late response," which were measured separately. As to paired stimuli, the "test" F-VEP emerged from electronic subtraction of the single F-VEP to the paired F-VEP. Grouped data were analyzed by means of nonparametric analyses of variance (ANOVAs). KEY FINDINGS: In patients, the single F-VEP showed some enhanced components in its early "main complex." Then, the "test" F-VEP behaved differently than controls, particularly if recorded with closed eyes, when the normal inhibition was abolished at given ISIs, corresponding to an internal frequency of 16-30 Hz. In patients with a posterior PPR, impaired inhibition was evident over the occipital region only, but in those with a widespread PPR, it also involved the central areas. SIGNIFICANCE: The paired F-VEP technique documents a defective inhibition in the visual system of photosensitive patients with IGE, whose features and timing likely underlie the PPR origin.

Cortical excitability changes associated with fixation-off sensitivity: a case report.

"Fixation-off sensitivity" (FOS) is an ideal human model for studying the features of epileptic discharges. Physiologically, FOS is expected to correspond to enhanced excitability of widespread cortical structures. To test this hypothesis, we measured by transcranial magnetic stimulation (TMS), the excitability level of the primary motor area in a 22-year-old woman with eyelid myoclonias and absences, who presented with generalized FOS. We also explored her visual system by pattern-reversal and flash-visual evoked potentials (VEPs). Both outside and within FOS, the cortical silent period was dramatically short, indicating defective γ-aminobutyric acid (GABA)(B) inhibition as a persistent background factor. The same was true for the short-interval intracortical inhibition, a TMS marker of cortical GABA(A) inhibition. The FOS state corresponded then to a pathologic enhancement of intracortical facilitation, a TMS marker of Glu/Asp transmission. During FOS, the flash VEP exhibited a hugely enhanced afterdischarge, expressing a pathologic overactivity of secondary visual areas. Within the limits of a single-case study, we thus provide electrophysiologic evidence supporting a grossly imbalanced cortical excitability, in both the frontal and posterior areas, as an important correlate of the present FOS subtype.