Sex differences in cerebral venous sinus thrombosis after adenoviral vaccination against COVID-19

INTRODUCTION

Cerebral venous sinus thrombosis associated with vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) is a severe disease with high mortality. There are few data on sex differences in CVST-VITT. The aim of our study was to investigate the differences in presentation, treatment, clinical course, complications, and outcome of CVST-VITT between women and men.

PATIENTS AND METHODS

We used data from an ongoing international registry on CVST-VITT. VITT was diagnosed according to the Pavord criteria. We compared the characteristics of CVST-VITT in women and men.

RESULTS

Of 133 patients with possible, probable, or definite CVST-VITT, 102 (77%) were women. Women were slightly younger [median age 42 (IQR 28-54) vs 45 (28-56)], presented more often with coma (26% vs 10%) and had a lower platelet count at presentation [median (IQR) 50x109/L (28-79) vs 68 (30-125)] than men. The nadir platelet count was lower in women [median (IQR) 34 (19-62) vs 53 (20-92)]. More women received endovascular treatment than men (15% vs 6%). Rates of treatment with intravenous immunoglobulins were similar (63% vs 66%), as were new venous thromboembolic events (14% vs 14%) and major bleeding complications (30% vs 20%). Rates of good functional outcome (modified Rankin Scale 0-2, 42% vs 45%) and in-hospital death (39% vs 41%) did not differ.

DISCUSSION AND CONCLUSIONS

Three quarters of CVST-VITT patients in this study were women. Women were more severely affected at presentation, but clinical course and outcome did not differ between women and men. VITT-specific treatments were overall similar, but more women received endovascular treatment.

Cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia in middle-income countries

BACKGROUND

Adenovirus-based COVID-19 vaccines are extensively used in low- and middle-income countries (LMICs). Remarkably, cases of cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) have rarely been reported from LMICs.

AIMS

We studied the frequency, manifestations, treatment, and outcomes of CVST-VITT in LMICs.

METHODS

We report data from an international registry on CVST after COVID-19 vaccination. VITT was classified according to the Pavord criteria. We compared CVST-VITT cases from LMICs to cases from high-income countries (HICs).

RESULTS

Until August 2022, 228 CVST cases were reported, of which 63 were from LMICs (all middle-income countries [MICs]: Brazil, China, India, Iran, Mexico, Pakistan, Turkey). Of these 63, 32 (51%) met the VITT criteria, compared to 103 of 165 (62%) from HICs. Only 5 of the 32 (16%) CVST-VITT cases from MICs had definite VITT, mostly because anti-platelet factor 4 antibodies were often not tested. The median age was 26 (interquartile range [IQR] 20-37) versus 47 (IQR 32-58) years, and the proportion of women was 25 of 32 (78%) versus 77 of 103 (75%) in MICs versus HICs, respectively. Patients from MICs were diagnosed later than patients from HICs (1/32 [3%] vs. 65/103 [63%] diagnosed before May 2021). Clinical manifestations, including intracranial hemorrhage, were largely similar as was intravenous immunoglobulin use. In-hospital mortality was lower in MICs (7/31 [23%, 95% confidence interval (CI) 11-40]) than in HICs (44/102 [43%, 95% CI 34-53], p = 0.039).

CONCLUSIONS

The number of CVST-VITT cases reported from LMICs was small despite the widespread use of adenoviral vaccines. Clinical manifestations and treatment of CVST-VITT cases were largely similar in MICs and HICs, while mortality was lower in patients from MICs.

Corticomotor excitability is altered in central neuropathic pain compared with non-neuropathic pain or pain-free patients

OBJECTIVES

Central neuropathic pain (CNP) is associated with altered corticomotor excitability (CE), which can potentially provide insights into its mechanisms. The objective of this study is to describe the CE changes that are specifically related to CNP.

METHODS

We evaluated CNP associated with brain injury after stroke or spinal cord injury (SCI) due to neuromyelitis optica through a battery of CE measurements and comprehensive pain, neurological, functional, and quality of life assessments. CNP was compared to two groups of patients with the same disease: i. with non-neuropathic pain and ii. without chronic pain, matched by sex and lesion location.

RESULTS

We included 163 patients (stroke=93; SCI=70: 74 had CNP, 43 had non-neuropathic pain, and 46 were pain-free). Stroke patients with CNP had lower motor evoked potential (MEP) in both affected and unaffected hemispheres compared to non- neuropathic pain and no-pain patients. Patients with CNP had lower amplitudes of MEPs (366 μV ±464 μV) than non-neuropathic (478 ±489) and no-pain (765 μV ± 880 μV) patients, p < 0.001. Short-interval intracortical inhibition (SICI) was defective (less inhibited) in patients with CNP (2.6±11.6) compared to no-pain (0.8±0.7), p = 0.021. MEPs negatively correlated with mechanical and cold-induced allodynia. Furthermore, classifying patients' results according to normative data revealed that at least 75% of patients had abnormalities in some CE parameters and confirmed MEP findings based on group analyses.

DISCUSSION

CNP is associated with decreased MEPs and SICI compared to non-neuropathic pain and no-pain patients. Corticomotor excitability changes may be helpful as neurophysiological markers of the development and persistence of pain after CNS injury, as they are likely to provide insights into global CE plasticity changes occurring after CNS lesions associated with CNP.

Association of Brain Age, Lesion Volume, and Functional Outcome in Patients With Stroke

BACKGROUND AND OBJECTIVES

Functional outcomes after stroke are strongly related to focal injury measures. However, the role of global brain health is less clear. In this study, we examined the impact of brain age, a measure of neurobiological aging derived from whole-brain structural neuroimaging, on poststroke outcomes, with a focus on sensorimotor performance. We hypothesized that more lesion damage would result in older brain age, which would in turn be associated with poorer outcomes. Related, we expected that brain age would mediate the relationship between lesion damage and outcomes. Finally, we hypothesized that structural brain resilience, which we define in the context of stroke as younger brain age given matched lesion damage, would differentiate people with good vs poor outcomes.

METHODS

We conducted a cross-sectional observational study using a multisite dataset of 3-dimensional brain structural MRIs and clinical measures from the ENIGMA Stroke Recovery. Brain age was calculated from 77 neuroanatomical features using a ridge regression model trained and validated on 4,314 healthy controls. We performed a 3-step mediation analysis with robust mixed-effects linear regression models to examine relationships between brain age, lesion damage, and stroke outcomes. We used propensity score matching and logistic regression to examine whether brain resilience predicts good vs poor outcomes in patients with matched lesion damage.

RESULTS

We examined 963 patients across 38 cohorts. Greater lesion damage was associated with older brain age (β = 0.21; 95% CI 0.04-0.38, p = 0.015), which in turn was associated with poorer outcomes, both in the sensorimotor domain (β = -0.28; 95% CI -0.41 to -0.15, p < 0.001) and across multiple domains of function (β = -0.14; 95% CI -0.22 to -0.06, p < 0.001). Brain age mediated 15% of the impact of lesion damage on sensorimotor performance (95% CI 3%-58%, p = 0.01). Greater brain resilience explained why people have better outcomes, given matched lesion damage (odds ratio 1.04, 95% CI 1.01-1.08, p = 0.004).

DISCUSSION

We provide evidence that younger brain age is associated with superior poststroke outcomes and modifies the impact of focal damage. The inclusion of imaging-based assessments of brain age and brain resilience may improve the prediction of poststroke outcomes compared with focal injury measures alone, opening new possibilities for potential therapeutic targets.

Site matters: Central neuropathic pain characteristics and somatosensory findings after brain and spinal cord lesions

BACKGROUND

It is unknown if different etiologies or lesion topographies influence central neuropathic pain (CNP) clinical manifestation.

METHODS

We explored the symptom-somatosensory profile relationships in CNP patients with different types of lesions to the central nervous system to gain insight into CNP mechanisms. We compared the CNP profile through pain descriptors, standardized bedside examination, and quantitative sensory test in two different etiologies with segregated lesion locations: the brain, central poststroke pain (CPSP, n = 39), and the spinal cord central pain due to spinal cord injury (CPSCI, n = 40) in neuromyelitis optica.

RESULTS

Results are expressed as median (25th to 75th percentiles). CPSP presented higher evoked and paroxysmal pain scores compared to CPSCI (p < 0.001), and lower cold thermal limen (5.6°C [0.0-12.9]) compared to CPSCI (20.0°C [4.2-22.9]; p = 0.004). CPSCI also had higher mechanical pain thresholds (784.5 mN [255.0-1078.0]) compared to CPSP (235.2 mN [81.4-1078.0], p = 0.006) and higher mechanical detection threshold compared to control areas (2.7 [1.5-6.2] vs. 1.0 [1.0-3.3], p = 0.007). Evoked pain scores negatively correlated with mechanical pain thresholds (r = -0.38, p < 0.001) and wind-up ratio (r = -0.57, p < 0.001).

CONCLUSIONS

CNP of different etiologies may present different pain descriptors and somatosensory profiles, which is likely due to injury site differences within the neuroaxis. This information may help better design phenotype mechanism correlations and impact trial designs for the main etiologies of CNP, namely stroke and spinal cord lesions. This study provides evidence that topography may influence pain symptoms and sensory profile. The findings suggest that CNP mechanisms might vary according to pain etiology or lesion topography, impacting future mechanism-based treatment choices.

Global Impact of the COVID-19 Pandemic on Stroke Volumes and Cerebrovascular Events: A 1-Year Follow-up

BACKGROUND AND OBJECTIVES

Declines in stroke admission, IV thrombolysis (IVT), and mechanical thrombectomy volumes were reported during the first wave of the COVID-19 pandemic. There is a paucity of data on the longer-term effect of the pandemic on stroke volumes over the course of a year and through the second wave of the pandemic. We sought to measure the effect of the COVID-19 pandemic on the volumes of stroke admissions, intracranial hemorrhage (ICH), IVT, and mechanical thrombectomy over a 1-year period at the onset of the pandemic (March 1, 2020, to February 28, 2021) compared with the immediately preceding year (March 1, 2019, to February 29, 2020).

METHODS

We conducted a longitudinal retrospective study across 6 continents, 56 countries, and 275 stroke centers. We collected volume data for COVID-19 admissions and 4 stroke metrics: ischemic stroke admissions, ICH admissions, IVT treatments, and mechanical thrombectomy procedures. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases.

RESULTS

There were 148,895 stroke admissions in the 1 year immediately before compared with 138,453 admissions during the 1-year pandemic, representing a 7% decline (95% CI [95% CI 7.1-6.9]; p < 0.0001). ICH volumes declined from 29,585 to 28,156 (4.8% [5.1-4.6]; p < 0.0001) and IVT volume from 24,584 to 23,077 (6.1% [6.4-5.8]; p < 0.0001). Larger declines were observed at high-volume compared with low-volume centers (all p < 0.0001). There was no significant change in mechanical thrombectomy volumes (0.7% [0.6-0.9]; p = 0.49). Stroke was diagnosed in 1.3% [1.31-1.38] of 406,792 COVID-19 hospitalizations. SARS-CoV-2 infection was present in 2.9% ([2.82-2.97], 5,656/195,539) of all stroke hospitalizations.

DISCUSSION

There was a global decline and shift to lower-volume centers of stroke admission volumes, ICH volumes, and IVT volumes during the 1st year of the COVID-19 pandemic compared with the prior year. Mechanical thrombectomy volumes were preserved. These results suggest preservation in the stroke care of higher severity of disease through the first pandemic year.

TRIAL REGISTRATION INFORMATION

This study is registered under NCT04934020.

Treatment results of carotid artery stenting in a developing country

OBJECTIVE

The purpose of this study was to investigate the details of minor complications of carotid artery stenting in a developing country.

METHODS

This was a retrospective, single-center study conducted on the target group consisting of 65 symptomatic patients who underwent carotid artery stenting. We assessed technical success rate, periprocedural complication within 30 days (hypotension, bradycardia, acute kidney injury, vasospasm, a transient ischemic attack, stroke, myocardial infarction, and death), and the differences between groups with and without complications.

RESULTS

Minor periprocedural complications occurred in 15 patients. In all, 8 (12.3%) had transient hypotension, 6 (9.2%) had bradycardia, 7 (10.7%) had acute kidney injury, 2 (3.1%) had vasospasm, and 1 (1.5%) had transient ischemic attack. A greater rate of minor complications was observed in women (p=0.051).

CONCLUSION

The results of the carotid artery stenting procedures performed in a developing country were acceptable.

Ischemic stroke caused by large-artery atherosclerosis: a red flag for subclinical coronary artery disease

Background

The coronary calcium score (CAC) measured on chest computerized tomography is a risk marker of cardiac events and mortality. We compared CAC scores in two multiethnic groups without symptomatic coronary artery disease: subjects in the chronic phase after stroke or transient ischemic attack and at least one symptomatic stenosis ≥50% in the carotid or vertebrobasilar territories (Group_athero) and a control group (Group_control).

Methods

In this cross-sectional study, Group_athero included two subgroups: Group_ExtraorIntra, with stenoses in either cervical or intracranial arteries, and Group_Extra&Intra, with stenoses in at least one cervical and one intracranial artery. Group_control had no history of prior stroke/transient ischemic attacks and no stenoses ≥50% in cervical or intracranial arteries. Age and sex were comparable in all groups. Frequencies of CAC ≥100 and CAC > 0 were compared between Group_athero and Group_control, as well as between Group_ExtraorIntr, Group_Extra&Intra, and Group_control, with bivariate logistic regressions. Multivariate analyses were also performed.

Results

A total of 120 patients were included: 80 in Group_athero and 40 in Group_control. CAC >0 was significantly more frequent in Group_athero (85%) than Group_control (OR, 4.19; 1.74-10.07; p = 0.001). Rates of CAC ≥100 were not significantly different between Group_athero and Group_control but were significantly greater in Group_Extra&Intra (n = 13) when compared to Group_control (OR 4.67; 1.21-18.04; p = 0.025). In multivariate-adjusted analyses, "Group_athero" and "Group_Extra&Intra" were significantly associated with CAC.

Conclusion

The frequency of coronary calcification was higher in subjects with stroke caused by large-artery atherosclerosis than in controls.

Access to rehabilitation after stroke in Brazil (AReA study): multicenter study protocol

BACKGROUND

Most of the Brazilian population relies on public healthcare and stroke is a major cause of disability in this country of continental dimensions. There is limited information about access to rehabilitation after stroke in Brazil.

OBJECTIVE

To provide comprehensive information about Access to Rehabilitation After discharge from public hospitals in Brazil (AReA study), up to 6 months after stroke.

METHODS

The present study intends to collect information from 17 public health centers in 16 Brazilian cities in the 5 macroregions of the country. Each center will include 36 participants (n = 612). The inclusion criteria are: age ≥ 18 years old; ischemic or hemorrhagic stroke, from 6 months to 1 year prior to the interview; admission to a public hospital in the acute phase after stroke; any neurological impairment poststroke; patient or caregiver able to provide informed consent and answer the survey. Patients can only be recruited in public neurology or internal medicine outpatient clinics. Outcomes will be assessed by a standard questionnaire about rehabilitation referrals, the rehabilitation program (current status, duration in months, number of sessions per week) and instructions received. In addition, patients will be asked about preferences for locations of rehabilitation (hospitals, clinics, or at home).

TRIAL STATUS

The study is ongoing. Recruitment started on January 31^st, 2020 and is planned to continue until June 2022.

CONCLUSION

The AReA study will fill a gap in knowledge about access to stroke rehabilitation in the public health system in different Brazilian regions.

Headache at the chronic stage of cerebral venous thrombosis

BACKGROUND

Headache is the most frequent symptom of cerebral venous thrombosis (CVT) but there is limited information about the frequency and phenotype of headache, weeks to months after cerebral venous thrombosis (post-cerebral venous thrombosis headache, post cerebral venous thrombosis headache).

OBJECTIVE

To assess the frequency, characteristics and predictors of PCH.

METHODS

In this cross-sectional study, the frequency and characteristics of PCH were assessed in cerebral venous thrombosis survivors. Patients were interviewed between six months and five years after the cerebral venous thrombosis diagnosis. Clinical and imaging characteristics at the time of cerebral venous thrombosis diagnosis, as well as history of headache prior to cerebral venous thrombosis were compared in subjects with (Group_PCH) and without PCH (Group_control).

RESULTS

Subjects (n = 100; 82% women) were assessed, on average, at 1.1 ± 1.6 years of follow-up. PCH was present in 59% of the patients, phenotypes of tension-type-like headache were present in 31/59 (52.6%) and of migraine-like headache in 16/59 (27.1%). History of primary headache prior to cerebral venous thrombosis was significantly more common (OR: 6.4; 95% CI: 1.7-36.3) in Group_PCH (33.9%) than in Group_control (7.3%).

CONCLUSION

Post cerebral venous thrombosis headache was present in more than half of the patients. History of prior headache may be a risk factor for post cerebral venous thrombosis headache. Prospective studies are required to confirm these findings and determine mechanisms, as well as interventions for prevention and treatment of post cerebral venous thrombosis headache.

Brazilian practice guidelines for stroke rehabilitation: Part II

The Brazilian Practice Guidelines for Stroke Rehabilitation - Part II, developed by the Scientific Department of Neurological Rehabilitation of the Brazilian Academy of Neurology (Academia Brasileira de Neurologia, in Portuguese), focuses on specific rehabilitation techniques to aid recovery from impairment and disability after stroke. As in Part I, Part II is also based on recently available evidence from randomized controlled trials, systematic reviews, meta-analyses, and other guidelines. Part II covers disorders of communication, dysphagia, postural control and balance, ataxias, spasticity, upper limb rehabilitation, gait, cognition, unilateral spatial neglect, sensory impairments, home rehabilitation, medication adherence, palliative care, cerebrovascular events related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the future of stroke rehabilitation, and stroke websites to support patients and caregivers. Our goal is to provide health professionals with more recent knowledge and recommendations for better rehabilitation care after stroke.

Brain stimulation can reduce unilateral spatial neglect after stroke: ELETRON trial

BACKGROUND

Rehabilitation top-down techniques based on brain stimulation present variable outcomes in unilateral spatial neglect (USN) after stroke. This study aimed to examine the effects of physical therapy after anodal and cathodal direct current stimulation (A-tDCS and C-tDCS, respectively) to improve visuospatial and functional impairments in individuals with USN after stroke.

METHODS

This double-blinded, pilot randomized clinical trial enrolled patients with USN after ischemic stroke. Randomization was stratified according to Behavior Inattention Test Conventional (BIT-C) and Catherine Bergego Scale (CBS). Outpatient physical therapy was conducted for 7.5 weeks after 20 min of tDCS. The primary outcome was the USN degree evaluated by the BIT-C. Secondary outcomes were the difference in CBS score, stroke severity [National Institutes of Health Stroke Scale (NIHSS)], disability [modified Rankin Scale (mRS)], autonomy [Barthel Index (BI), functional independence measure (FIM)], and quality of life (EQ-5D). Outcomes were analyzed using ANCOVA model corrected by age, baseline NIHSS and baseline BIT-C. Pairwise posthoc comparisons were performed using Bonferroni correction.

RESULTS

In the primary outcomes, A-tDCS led to greater improvement in BIT-C after intervention (MD: 18.4; 95%CI: 3.9-32.8; p=0.008) compared to sham. However, no significant differences were observed between A-tDCS and C-tDCS (MD: 13.9; 95%CI: -0.3-28.1; p=0.057), or C-tDCS and sham (MD: 4.5; 95%CI: -9.7-18.8; p=0.99). There were no significant differences between groups in terms of secondary outcomes.

CONCLUSIONS

A-tDCS associated with physical therapy can decrease the severity of USN after stroke. However, these preliminary findings must be confirmed by collecting additional evidence in a larger phase III trial.

REGISTRATION

URL: https://ensaiosclinicos.gov.br/; Unique Identifier RBR-78jvzx This article is protected by copyright. All rights reserved.

Cerebral venous thrombosis

Cerebral venous sinus thrombosis (CVT) consists of partial or complete occlusion of a sinus or a cerebral vein. CVT represents 0.5-1% of all strokes and is more frequent in young women. This review discusses particular aspects of CVT diagnosis and management: decompressive craniectomy (DC), anticoagulation with direct oral anticoagulants (DOACs), CVT after coronavirus-disease 19 (COVID-19) and Vaccine-Induced Immune Thrombotic Thrombocytopenia (VITT).

Dissecting central post-stroke pain: a controlled symptom-psychophysical characterization

Central post-stroke pain affects up to 12% of stroke survivors and is notoriously refractory to treatment. However, stroke patients often suffer from other types of pain of non- neuropathic nature (musculoskeletal, inflammatory, complex regional) and no head-to-head comparison of their respective clinical and somatosensory profiles has been performed so far.

We compared 39 patients with definite central neuropathic post-stroke pain with two matched- control groups: 32 patients with exclusively non-neuropathic pain developed after stroke and 31 stroke patients not complaining of pain. Patients underwent deep phenotyping via a comprehensive assessment including clinical exam, questionnaires and quantitative sensory testing to dissect central post-stroke pain from chronic pain in general and stroke.

While central post-stroke pain was mostly located in the face and limbs, non-neuropathic pain was predominantly axial and located in neck, shoulders and knees (p&lt;0.05). Neuropathic Pain Symptom Inventory clusters burning (82.1%, n=32, p&lt;0.001), tingling (66.7%, n= 26, p&lt;0.001) and evoked by cold (64.1%, n=25, p&lt;0.001) occurred more frequently in central post-stroke pain. Hyperpathia, thermal and mechanical allodynia also occurred more commonly in this group (p&lt;0.001), which also presented higher levels of deafferentation (p&lt;0.012) with more asymmetric cold and warm detection thresholds compared to controls. In particular, cold hypoesthesia (considered when the threshold of the affected side was less than 41% of the contralateral threshold) odds ratio was 12 (95%CI: 3.8-41.6) for neuropathic pain. Additionally, cold detection threshold/ warm detection threshold ratio correlated with the presence of neuropathic pain (ρ=-0.4, p&lt; 0.001). Correlations were found between specific neuropathic pain symptom clusters and quantitative sensory testing: paroxysmal pain with cold (ρ=-0.4; p=0.008) and heat pain thresholds (ρ=0.5; p=0.003), burning pain with mechanical detection (ρ= -0.4; p=0.015) and mechanical pain thresholds (ρ=-0.4, p&lt;0.013), evoked pain with mechanical pain threshold (ρ= -0.3; p=0.047). Logistic regression showed that the combination of cold hypoesthesia on quantitative sensory testing, the Neuropathic Pain Symptom Inventory, and the allodynia intensity on bedside examination explained 77% of the occurrence of neuropathic pain.

These findings provide insights into the clinical-psychophysics relationships in central post-stroke pain and may assist more precise distinction of neuropathic from non-neuropathic post-stroke pain in clinical practice and in future trials.

Outcomes of acute basilar artery occlusion-real-world experience in a middle-income country

OBJECTIVES

Our goal was to describe outcomes in a single-center, real-world series of patients with acute basilar artery occlusion in a middle-income country. In addition, we assessed potential outcome predictors.

MATERIAL AND METHODS

Data from 28 patients were retrospectively reviewed. The primary outcome was death until last follow-up. Other outcomes were rates of favorable outcome until last follow-up and rates of intracranial hemorrhage. Outcomes were compared in subgroups according to several variables, including reperfusion (REP group) or no reperfusion (NOREP group) interventions, with chi-squared, Fisher's exact test, or Mann-Whitney tests.

RESULTS

The rate of overall intrahospital death was 46%. Death until last follow-up occurred in 8/17 (47%) in the REP and in 7/11 (63%) of the NOREP group. Favorable outcomes were observed in 35.7% of the patients: 8/17 (47%) in REP and in 2/11 (18.1%) in NOREP. NIH stroke scale scores were significantly lower in patients with favorable outcomes. Intracranial hemorrhage was observed in 6/28 (21.4%) of the patients (all in REP group). Twenty patients were treated with anticoagulants within the first 24 h. No hemorrhage was observed in those treated with enoxaparin, while three occurred in subjects treated with unfractionated heparin.

CONCLUSION

Together with other series, our results underscore the relevance of NIH stroke scale at admission as a prognostic marker, the importance of reperfusion to improve outcomes, and the need of clinical trials to compare the impact of treatment with anticoagulants within first 24 h in basilar artery occlusion.

Effects of Repetitive Peripheral Sensory Stimulation in the Subacute and Chronic Phases After Stroke: Study Protocol for a Pilot Randomized Trial

Background

Repetitive peripheral nerve sensory stimulation (RPSS) is a potential add-on intervention to motor training for rehabilitation of upper limb paresis after stroke. Benefits of RPSS were reported in subjects in the chronic phase after stroke, but there is limited information about the effects of this intervention within the 1st weeks or months. The primary goal of this study is to compare, in a head-to-head proof-of-principle study, the impact of a single session of suprasensory vs. subsensory RPSS on the upper limb motor performance and learning in subjects at different phases after stroke subacute and chronic phases and mild upper limb motor impairments after stroke. In addition, we examine the effects of RPSS on brain perfusion, functional imaging activation, and γ-aminobutyric acid (GABA) levels. Subjects with mild upper limb motor impairments will be tested with MRI and clinical assessment either at an early (7 days to 3 months post-stroke) or at a chronic (>6 months) stage after stroke.

Methods

In this multicenter, randomized, parallel-group, proof-of-principle clinical trial with blinded assessment of outcomes, we compare the effects of one session of suprasensory or subsensory RPSS in patients with ischemic or hemorrhagic stroke and upper limb paresis. Clinical assessment and MRI will be performed only once in each subject (either at an early or at a chronic stage). The primary outcome is the change in performance in the Jebsen–Taylor test. Secondary outcomes: hand strength, cerebral blood flow assessed with arterial spin labeling, changes in the blood oxygenation level-dependent (BOLD) effect in ipsilesional and contralesional primary motor cortex (M1) on the left and the right hemispheres assessed with functional MRI (fMRI) during a finger-tapping task performed with the paretic hand, and changes in GABA levels in ipsilesional and contralesional M1 evaluated with spectroscopy. The changes in outcomes will be compared in four groups: suprasensory, early; subsensory, early; suprasensory, chronic; and subsensory, chronic.

Discussion

The results of this study are relevant to inform future clinical trials to tailor RPSS to patients more likely to benefit from this intervention.

Trial Registration

NCT03956407.

Impact of Extent of Investigation on Causes of Ischemic Stroke in The Young: A Retrospective Evaluation

BACKGROUND

Despite enormous advances in the diagnosis and treatment of ischemic stroke over the past decades, the extent of "standard" investigation to define its causes is heterogeneous. Young patients often undergo a myriad of diagnostic tests in developed countries, but the cost-effectiveness of this approach is uncertain.

OBJECTIVES

Our main goal was to compare the frequencies of ischemic stroke of undetermined and determined etiologies in young patients with "complete" or "incomplete" investigation according to either a stepwise or an extensive protocol.

METHODS

Data from 143 young patients with ischemic stroke were reviewed. For each patient, available data were assessed by means of a stepwise and an extensive protocol of investigation. We compared the frequencies of ischemic stroke of undetermined and determined etiology according to "complete" or "incomplete" investigation according to each protocol.

RESULTS

Completeness of investigation led to a significant increase in determination of stroke etiology when a stepwise approach but not an extensive protocol was applied.

CONCLUSIONS

These results suggest that ordering an extensive workup to all young patients does not enhance the capability of determining causes of ischemic stroke. Evidence-based guidelines to define pathways of investigation and consensus about the interpretation of tests are deeply needed.

Cannabinoids in Neurology - Position paper from Scientific Departments from Brazilian Academy of Neurology

Cannabinoids comprehend endocannabinoids, phytocannabinoids, and synthetic cannabinoids, with actions both in the central and peripherical nervous systems. A considerable amount of publications have been made in recent years, although cannabis has been known for over a thousand years. Scientific Departments from the Brazilian Academy of Neurology described evidence for medical use in their areas. Literature is constantly changing, and possible new evidence can emerge in the next days or months. Prescription of these substances must be discussed with patients and their families, with knowledge about adverse events and their efficacy.

Effects of Robotic Therapy Associated With Noninvasive Brain Stimulation on Upper-Limb Rehabilitation After Stroke: Systematic Review and Meta-analysis of Randomized Clinical Trials

BACKGROUND

Robot-assisted therapy and noninvasive brain stimulation (NIBS) are promising strategies for stroke rehabilitation.

OBJECTIVE

This systematic review and meta-analysis aims to evaluate the evidence of NIBS as an add-on intervention to robotic therapy in order to improve outcomes of upper-limb motor impairment or activity in individuals with stroke.

METHODS

This study was performed according to the PRISMA Protocol and was previously registered on the PROSPERO Platform (CRD42017054563). Seven databases and gray literature were systematically searched by 2 reviewers, and 1176 registers were accessed. Eight randomized clinical trials with upper-limb body structure/function or activity limitation outcome measures were included. Subgroup analyses were performed according to phase poststroke, device characteristics (ie, arm support, joints involved, unimanual or bimanual training), NIBS paradigm, timing of stimulation, and number of sessions. The Grade-Pro Software was used to assess quality of the evidence.

RESULTS

A nonsignificant homogeneous summary effect size was found both for body structure function domain (mean difference [MD] = 0.15; 95% CI = -3.10 to 3.40; P = 0.93; I² = 0%) and activity limitation domain (standard MD = 0.03; 95% CI = -0.28 to 0.33; P = 0.87; I² = 0%).

CONCLUSIONS

According to this systematic review and meta-analysis, at the moment, there are not enough data about the benefits of NIBS as an add-on intervention to robot-assisted therapy on upper-limb motor function or activity in individuals with stroke.

Management of acute stroke and urgent neurointerventional procedures during COVID-19 pandemic: recommendations on the Scientific Department on Cerebrovascular Diseases of the Brazilian Academy of Neurology, Brazilian Society of Cerebrovascular Diseases and Brazilian Society of Neuroradiology

INTRODUCTION

Although the 2019 severe acute respiratory syndrome coronavirus 2 infection (SARS-CoV-2, COVID-19) pandemic poses new challenges to the healthcare system to provide support for thousands of patients, there is special concern about common medical emergencies, such as stroke, that will continue to occur and will require adequate treatment. The allocation of both material and human resources to fight the pandemic cannot overshadow the care for acute stroke, a time-sensitive emergency that with an inefficient treatment will further increase mortality and long-term disability.

OBJECTIVE

This paper summarizes the recommendations from the Scientific Department on Cerebrovascular Diseases of the Brazilian Academy of Neurology, the Brazilian Society of Cerebrovascular Diseases and the Brazilian Society of Neuroradiology for management of acute stroke and urgent neuro-interventional procedures during the COVID-19 pandemic, including proper use of screening tools, personal protective equipment (for patients and health professionals), and patient allocation.

Sensorimotor white matter projections and disease severity in primary Restless Legs Syndrome/Willis-Ekbom disease: a multimodal DTI analysis

BACKGROUND

Restless Legs Syndrome, a potentially disabling sleep disorder, also known as Willis-Ekbom disease (RLS/WED), may be caused by loss of inhibitory modulation of descending central motor pathways, structural changes in the somatosensory cortex, abnormal connectivity between motor and sensory areas, as well as by subtle abnormalities in white matter micro-organization.

OBJECTIVE

To compare diffusion-tensor imaging (DTI) metrics in areas associated with sensory or motor function, as well as sensorimotor integration, between subjects with primary mild-to-severe RLS/WED and controls.

METHODS

DTI metrics were assessed in 38 subjects with RLS/WED (14 mild to moderate, 24 severe to very severe) and 24 healthy age-matched controls with whole-brain Tract Based Spatial Statistics (TBSS), Region-of-interest (ROI) and probabilistic tractography based analyses. The ROIs corresponded to the corticospinal tract (CST) at the level of the cerebral peduncle; the superior, middle and inferior cerebellar peduncles. Subgroup analyses were made according to the severity of RLS/WED symptoms. The corticospinal tract was evaluated with probabilistic tractography. We also explored associations between significant findings and severity of symptoms with the Spearman's correlation coefficient.

RESULTS

TBSS analysis revealed decreased axial diffusivity (AD) in the left posterior thalamic radiation in RLS/WED. In subjects with severe RLS/WED, AD was reduced in the left posterior corona radiata and this reduction was negatively correlated with severity of symptoms. ROI-based analysis showed that radial diffusivity (RD) was increased in the superior cerebellar peduncles of individuals with severe RLS/WED. Tractography did not show between-group or subgroup differences.

CONCLUSIONS

Our results are consistent with subtle white matter changes, prominently in RLS/WED subjects with more severe symptoms, in areas related to sensory or motor function, as well as to sensorimotor integration, compared to controls. These findings support the hypothesis, raised by prior pathophysiological studies, of defective integration within these networks.

Short-interval intracortical inhibition is decreased in restless legs syndrome across a range of severity

BACKGROUND

Decreased short-interval intracortical inhibition (SICI) to transcranial magnetic stimulation (TMS) of the primary motor cortex was described in subjects with restless legs syndrome/Willis-Ekbom disease (RLS/WED). It remained to be determined whether the magnitude of SICI decrease would be similar across levels of RLS/WED severity. Moreover, it was unknown whether, in addition to decreases in SICI, changes in cortical thickness or area could be detected in subjects with RLS/WED compared to controls. The objective of this study was to compare SICI, cortical thickness, and cortical area in subjects with idiopathic mild to moderate RLS/WED, severe to very severe RLS/WED, and controls.

METHODS

The severity of RLS/WED was assessed by the International Restless Legs Syndrome Severity Scale (IRLSS). SICI and 3T magnetic resonance imaging (MRI) data of subjects with RLS/WED and controls were compared. A receiver operating characteristic curve for SICI was designed for discrimination of participants with RLS/WED from controls. Cortical thickness and area were assessed by automated surface-based analysis.

RESULTS

SICI was significantly reduced in patients with mild to moderate and severe to very severe RLS/WED, compared to controls (one-way analysis of variance: F = 9.62, p < 0.001). Receiver operating characteristic curve analysis predicted RLS/WED when SICI was above 35% (area under the curve = 0.79, 95% CI 0.67-0.91, p < 0.001). Analyses of the whole brain and of regions of interest did not reveal differences in gray matter thickness or area between controls and subjects with RLS/WED.

CONCLUSION

SICI is an accurate cortical biomarker that can support the diagnosis of RLS/WED even in subjects with mild symptoms, but cortical thickness and area were not useful for discriminating subjects with this condition from controls.

Does stroke laterality predict major depression and cognitive impairment after stroke? Two-year prospective evaluation in the EMMA study

Depression and cognitive impairment are common conditions following stroke. We aimed to evaluate stroke laterality as predictor of post-stroke depression (PSD) and cognitive impairment (PCI) in a stroke cohort. Major depression (Patient Health Questionnaire-9, score ≥ 10) and cognitive impairment (Modified Telephone Interview for Cognitive Status, score < 14) were evaluated at 6 months and yearly up to 2 years. Survival analyses were performed by Kaplan-Meier curves and Cox logistic regression models, adjusted for potential confounders (cumulative hazard ratio, HR; 95% confidence interval, CI), for the likelihood of subsequent PSD or PCI progression at 6 months and 2 years, according to stroke laterality (right hemisphere-reference). Among 100 stroke patients, we found 19% had PSD and 38% had PCI 2 years after stroke. Most participants (53%) presented right-sided stroke. However, right-sided stroke was not associated with PSD or PCI. Overall, left-sided stroke was an independent and long-term predictor of PCI, but not of major depression. Left-sided stroke was associated with a high probability of PCI (42.6% and 53.2%, respectively at 6 months and 2 years, p-log-rank: 0.002). The HR of PCI due to left-sided stroke was 3.25 (95%CI, 1.30-8.12) at 6 months and remained almost the same at 2 years (HR,3.22;95%CI, 1.43-7.28). The risk of having worse cognition status increased by >3 times, 2 years after stroke. The results support the hypothesis that involvement of networks in the left, but not in the right hemisphere, contribute to long-term cognitive impairment. Lesion laterality did not influence the risk of PSD.

The cost of stroke in private hospitals in Brazil: a one-year prospective study

OBJECTIVE

Few studies from low- and middle-income countries have assessed stroke and cerebral reperfusion costs from the private sector. To measure the in-hospital costs of ischemic stroke (IS), with and without cerebral reperfusion, primary intracerebral hemorrhage (PIH), subarachnoid hemorrhage (SAH) and transient ischemic attacks (TIA) in two private hospitals in Joinville, Brazil.

METHODS

Prospective disease-cost study. All medical and nonmedical costs for patients admitted with any stroke type or TIA were consecutively determined in 2016-17. All costs were adjusted to the gross domestic product deflator index and purchasing power parity.

RESULTS

We included 173 patients. The median cost per patient was US$3,827 (IQR: 2,800-8,664) for the 131 IS patients; US$2,315 (IQR: 1,692-2,959) for the 27 TIA patients; US$16,442 (IQR: 5,108-33,355) for the 11 PIH patients and US$28,928 (IQR: 12,424-48,037) for the four SAH patients (p < 0.00001). For the six IS patients who underwent intravenous thrombolysis, the median cost per patient was US$11,463 (IQR: 8,931-14,291), and for the four IS patients who underwent intra-arterial thrombectomy, the median cost per patient was US$35,092 (IQR: 31,833-37,626; p < 0.0001). A direct correlation was found between cost and length of stay (r = 0.67, p < 0.001).

CONCLUSIONS

Stroke is a costly disease. In the private sector, the costs of cerebral reperfusion for IS treatment were three-to-ten times higher than for usual treatments. Therefore, cost-effectiveness studies are urgently needed in low- and middle-income countries.

The cost of stroke in a public hospital in Brazil: a one-year prospective study

OBJECTIVE

Low- and middle-income countries face tight health care budgets, not only new resources, but also costly therapeutic resources for treatment of ischemic stroke (IS). However, few prospective data about stroke costs including cerebral reperfusion from low- and middle-income countries are available. To measure the costs of stroke care in a public hospital in Joinville, Brazil.

METHODS

We prospectively assessed all medical and nonmedical costs of inpatients admitted with a diagnosis of any stroke or transient ischemic attack over one year, analyzed costs per type of stroke and treatment, length of stay (LOS) and compared hospital costs with government reimbursement.

RESULTS

We evaluated 274 patients. The total cost for the year was US$1,307,114; the government reimbursed the hospital US$1,095,118. We found a significant linear correlation between LOS and costs (r = 0.71). The median cost of 134 IS inpatients who did not undergo cerebral reperfusion (National Institutes of Health Stroke Scale [NIHSS] median = 3 ) was US$2,803; for IS patients who underwent intravenous (IV) alteplase (NIHSS 10), the median was US$5,099, and for IS patients who underwent IV plus an intra-arterial (IA) thrombectomy (NIHSS > 10), the median cost was US$10,997. The median costs of a primary intracerebral hemorrhage, subarachnoid hemorrhage, and transient ischemic attack were US$2,436, US$8,031 and US$2,677, respectively.

CONCLUSIONS

Reperfusion treatments were two-to-four times more expensive than conservative treatment. A cost-effectiveness study of the IS treatment option is necessary.

Method to assess the mismatch between the measured and nominal parameters of transcranial magnetic stimulation devices

BACKGROUND

Small variations in TMS parameters, such as pulse frequency and amplitude may elicit distinct neurophysiological responses. Assessing the mismatch between nominal and experimental parameters of TMS stimulators is essential for safe application and comparisons of results across studies.

NEW METHOD

A search coil was used to assess exactness and precision errors of amplitude and timing parameters such as interstimulus interval, the period of pulse repetition, and intertrain interval of TMS devices. The method was validated using simulated pulses and applied to six commercial stimulators in single-pulse (spTMS), paired-pulse (ppTMS), and repetitive (rTMS) protocols, working at several combinations of intensities and frequencies.

RESULTS

In a simulated signal, the maximum exactness error was 1.7% for spTMS and the maximum precision error 1.9% for ppTMS. Three out of six TMS commercial devices showed exactness and precision errors in spTMS amplitude higher than 5%. Moreover, two devices showed amplitude exactness errors higher than 5% in rTMS with parameters suggested by the manufactures.

COMPARISON WITH EXISTING METHODS

Currently available tools allow characterization of induced electric field intensity and focality, and pulse waveforms of a single TMS pulse. Our method assesses the mismatch between nominal and experimental values in spTMS, ppTMS and rTMS protocols through the exactness and precision errors of amplitude and timing parameters.

CONCLUSION

This study highlights the importance of evaluating the physical characteristics of TMS devices and protocols, and provides a method for on-site quality assessment of multiple stimulation protocols in clinical and research environments.

Post-stroke depression and cognitive impairment: Study design and preliminary findings in a Brazilian prospective stroke cohort (EMMA study)

BACKGROUND

Post-stroke depression (PSD) and cognitive impairment (PCI) are common conditions. This study aims to describe the protocol and preliminary findings of an investigation into factors associated with PSD and PCI 1-3 months after stroke (subacute phase) in survivors from the Study of Stroke Mortality and Morbidity (EMMA study).

METHODS

Stroke patients underwent to clinical and neurological evaluations on admission to hospital. Cerebral magnetic resonance and biomarkers (serotonin, BDNF, IL-6 and IL-18) were carried out in the subacute phase. DSM-IV major depression for the diagnosis of PSD, cognitive functioning for the diagnosis of PCI and functional disability were also recorded at same time.

RESULTS

Of the 103 eligible patients, 85.4% had ischemic stroke and 73.7% had first-ever stroke. In the subacute phase, 27.2% had PCI and 13.6% had current PSD (5.8% with 'first episode' and 7.8% with 'recurrent' depression). PCI was associated with low education (0-7 years of formal education: 75%) and ageing (median age: 70; interquartile range: 59-75 y-old). Left-sided stroke was more frequently associated with increased PCI than right-sided stroke (71.4% vs. 28.4%, p = 0.005). PSD was neither associated with stroke laterality nor tentorial area. Overall, biomarkers levels were not alterated in patients with PSD and PCI.

LIMITATIONS

Findings are based on small sample and less disabled stroke participants, e.g. those without aphasia and deafness.

CONCLUSIONS

Findings reinforce the need of early recognition and rehabilitation of PCI and PSD, mainly among those less educated and with left-sided stroke. PSD might occur through a pathophysiological pathway other than classical depression.

Success of promotion strategies for a stroke rehabilitation protocol

OBJECTIVE

To prospectively evaluate the success of promotion strategies for a protocol of motor rehabilitation strategies for patients with stroke at Albert Einstein Hospital.

METHODS

In a clinical trial of neuromodulation and rehabilitation for patients with stroke, conventional methods of dissemination and publications about the research protocol in social networks or on the hospital's website were performed. Frequencies of types of advertisements that reached potentially eligible subjects were calculated.

RESULTS

Data from 80 potentially eligible patients were analyzed. The types of ads that motivated contacts more frequently were social media (38.8%) and information provided to physicians from other hospitals (23.8%) (p=0,288). The frequencies of contacts motivated by publications on the internet (53%) and conventional strategies (47%) were similar. Facebook was the digital strategy associated with the higher number of contacts, followed by the hospital's website.

CONCLUSION

Social networks and websites can be as effective as traditional methods of advertisement, in order to reach patients for stroke rehabilitation protocols. These results may have an impact on the planning of clinical trials, including studies that evaluate effects of rehabilitation interventions in patients with stroke.

A Brazilian-Portuguese version of the Kinesthetic and Visual Motor Imagery Questionnaire

Motor imagery has emerged as a potential rehabilitation tool in stroke. The goals of this study were: 1) to develop a translated and culturally-adapted Brazilian-Portugese version of the Kinesthetic and Visual Motor Imagery Questionnaire (KVIQ20-P); 2) to evaluate the psychometric characteristics of the scale in a group of patients with stroke and in an age-matched control group; 3) to compare the KVIQ20 performance between the two groups. Test-retest, inter-rater reliabilities, and internal consistencies were evaluated in 40 patients with stroke and 31 healthy participants. In the stroke group, ICC confidence intervals showed excellent test-retest and inter-rater reliabilities. Cronbach's alpha also indicated excellent internal consistency. Results for controls were comparable to those obtained in persons with stroke. The excellent psychometric properties of the KVIQ20-P should be considered during the design of studies of motor imagery interventions for stroke rehabilitation.

Repetitive Peripheral Sensory Stimulation and Upper Limb Performance in Stroke: A Systematic Review and Meta-analysis

BACKGROUND

Enhancement of sensory input in the form of repetitive peripheral sensory stimulation (RPSS) can enhance excitability of the motor cortex and upper limb performance.

OBJECTIVE

To perform a systematic review and meta-analysis of effects of RPSS compared with control stimulation on improvement of motor outcomes in the upper limb of subjects with stroke.

METHODS

We searched studies published between 1948 and December 2017 and selected 5 studies that provided individual data and applied a specific paradigm of stimulation (trains of 1-ms pulses at 10 Hz, delivered at 1 Hz). Continuous data were analyzed with means and standard deviations of differences in performance before and after active or control interventions. Adverse events were also assessed.

RESULTS

There was a statistically significant beneficial effect of RPSS on motor performance (standard mean difference between active and control RPSS, 0.67; 95% CI, 0.09-1.24; I² = 65%). Only 1 study included subjects in the subacute phase after stroke. Subgroup analysis of studies that only included subjects in the chronic phase showed a significant effect (1.04; 95% CI, 0.66-1.42) with no heterogeneity. Significant results were obtained for outcomes of body structure and function as well as for outcomes of activity limitation according to the International Classification of Function, Disability and Health, when only studies that included subjects in the chronic phase were analyzed. No serious adverse events were reported.

CONCLUSIONS

RPSS is a safe intervention with potential to become an adjuvant tool for upper extremity paresis rehabilitation in subjects with stroke in the chronic phase.

Noninvasive Brain Stimulations for Unilateral Spatial Neglect after Stroke: A Systematic Review and Meta-Analysis of Randomized and Nonrandomized Controlled Trials

Background

Unilateral spatial neglect (USN) is the most frequent perceptual disorder after stroke. Noninvasive brain stimulation (NIBS) is a tool that has been used in the rehabilitation process to modify cortical excitability and improve perception and functional capacity.

Objective

To assess the impact of NIBS on USN after stroke.

Methods

An extensive search was conducted up to July 2016. Studies were selected if they were controlled and noncontrolled trials examining transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and theta burst stimulation (TBS) in USN after stroke, with outcomes measured by standardized USN and functional tests.

Results

Twelve RCTs (273 participants) and 4 non-RCTs (94 participants) proved eligible. We observed a benefit in overall USN measured by the line bisection test with NIBS in comparison to sham (SMD -2.35, 95% CI -3.72, -0.98; p = 0.0001); the rTMS yielded results that were consistent with the overall meta-analysis (SMD -2.82, 95% CI -3.66, -1.98; p = 0.09). The rTMS compared with sham also suggested a benefit in overall USN measured by Motor-Free Visual Perception Test at both 1 Hz (SMD 1.46, 95% CI 0.73, 2.20; p < 0.0001) and 10 Hz (SMD 1.19, 95% CI 0.48, 1.89; p = 0.54). There was also a benefit in overall USN measured by Albert's test and the line crossing test with 1 Hz rTMS compared to sham (SMD 2.04, 95% CI 1.14, 2.95; p < 0.0001).

Conclusions

The results suggest a benefit of NIBS on overall USN, and we conclude that rTMS is more efficacious compared to sham for USN after stroke.

Inference comprehension in text reading: Performance of individuals with right- versus left-hemisphere lesions and the influence of cognitive functions

Background

Right-hemisphere lesions (RHL) may impair inference comprehension. However, comparative studies between left-hemisphere lesions (LHL) and RHL are rare, especially regarding reading comprehension. Moreover, further knowledge of the influence of cognition on inferential processing in this task is needed.

Objectives

To compare the performance of patients with RHL and LHL on an inference reading comprehension task. We also aimed to analyze the effects of lesion site and to verify correlations between cognitive functions and performance on the task.

Methods

Seventy-five subjects were equally divided into the groups RHL, LHL, and control group (CG). The Implicit Management Test was used to evaluate inference comprehension. In this test, subjects read short written passages and subsequently answer five types of questions (explicit, logical, distractor, pragmatic, and other), which require different types of inferential reasoning. The cognitive functional domains of attention, memory, executive functions, language, and visuospatial abilities were assessed using the Cognitive Linguistic Quick Test (CLQT).

Results

The LHL and RHL groups presented difficulties in inferential comprehension in comparison with the CG. However, the RHL group presented lower scores than the LHL group on logical, pragmatic and other questions. A covariance analysis did not show any effect of lesion site within the hemispheres. Overall, all cognitive domains were correlated with all the types of questions from the inference test (especially logical, pragmatic, and other). Attention and visuospatial abilities affected the scores of both the RHL and LHL groups, and only memory influenced the performance of the RHL group.

Conclusions

Lesions in either hemisphere may cause difficulties in making inferences during reading. However, processing more complex inferences was more difficult for patients with RHL than for those with LHL, which suggests that the right hemisphere plays an important role in tasks with higher comprehension demands. Cognition influences inferential processing during reading in brain-injured subjects.

Interictal abnormal fMRI activation of visual areas during a motor task cued by visual stimuli in migraine

Objective

To assess changes in blood-oxygen-level-dependent activity after light deprivation compared to regular light exposure in subjects with migraine in the interictal state and in controls.

Methods

Ten subjects with migraine and ten controls participated in two sessions of functional magnetic resonance imaging. In each session, they performed a finger-tapping task with the right hand, cued by visual stimuli. They were scanned before and after 30 minutes of light deprivation or light exposure. In subjects with migraine, functional magnetic resonance imaging was performed interictally. Analysis of variance was made with the factors time (before or after), session (light deprivation or exposure), and group (migraine or control).

Results

There were significant “group” effects in a cluster in the bilateral cuneus encompassing the superior border of the calcarine sulcus and extrastriate cortex. There were no significant effects of “time”, “session”, or interactions between these factors.

Conclusion

The main result of this study is consistent with aberrant interictal processing of visual information in migraine. Light deprivation did not modulate functional magnetic resonance imaging activity in subjects with or without migraine.

The duration of the cortical silent period is not abnormal in Restless Legs Syndrome/Willis-Ekbom Disease

OBJECTIVE

To compare the duration of the cortical silent period (CSP) measured in a hand muscle in subjects with primary Restless Legs Syndrome (RLS/WED) and controls, using four different methods of analysis.

METHODS

The CSP to transcranial magnetic stimulation of the dominant motor cortex was assessed in the abductor digiti minimi of 33 subjects with RLS/WED and 24 controls. CSP duration was measured by an automated and three visually-guided methods.

RESULTS

There were significant differences between absolute values of CSP duration according to the method of analysis. However, irrespectively of the method used for CSP assessment, no differences were found between measurements performed in subjects with RLS/WED and subjects from the control group.

CONCLUSIONS

Absolute values of CSP durations analyzed by different methods should not be directly compared, because significantly different results can be obtained from the same data set.

SIGNIFICANCE

The CSP assessed from a hand muscle is unlikely to be a biomarker of primary RLS/WED. Our results highlight the importance of standardizing the definition of CSP onset and offset, as well as of describing in detail the methodology chosen to record and measure CSP duration, in order to enable comparisons between studies.

Treatment of unilateral spatial neglect after stroke using transcranial direct current stimulation (ELETRON trial): study protocol for a randomized controlled trial

Background

Unilateral spatial neglect (USN) is characterized by the inability to report or respond to people or objects that are presented in the spatial hemisphere that is contralateral to the lesioned hemisphere of the brain. USN has been associated with poor functional outcomes and long stays in hospitals and rehabilitation centers. Noninvasive brain stimulation, such as transcranial direct current stimulation (tDCS), has been used in people who have been affected by USN after stroke. The effects of such treatment could provide new insights for health professionals and policy-makers. The aim of this study will be to evaluate the effectiveness and safety of tDCS for USN after stroke.

Methods

A prospective randomized controlled trial with two parallel groups will be conducted, which will aim to recruit 60 patients with USN after ischemic or hemorrhagic stroke. Participants will be randomly placed into the following four treatment groups: (1) anodal tDCS over the right parietal lobe (n = 15), (2) cathodal tDCS over the left parietal lobe (n = 15), (3) a sham group of anodal tDCS over the right parietal lobe (n = 15), and (4) a sham group of cathodal tDCS over the left parietal lobe (n = 15). Blinded assessors will conduct two baseline assessments and one post-intervention assessment. The primary outcome measure will be the level of USN as assessed by the conventional Behavioral Inattention Tasks and the Catherine Bergego Scale. Secondary measures will include neurological capacity (based on the Scandinavian Stroke Scale), functional capacity (based on the Functional Independence Measure and Modified Rankin Scale), autonomy (based on the Barthel Index), and quality of life (based on the EuroQol-5D). Group allocation will be concealed, and all analyses will be based on an intention-to-treat principle.

Discussion

This study will explore the effects of more than 15 sessions of tDCS on the level of USN, functional capacity, autonomy, and quality of life in patients with USN after stroke. This proposed study has the potential to identify a new, evidence-based intervention that can enhance perception and independent living in patients with USN after stroke.

Trial registration

REBEC - RBR-78jvzx, registered on 13 March 2016.

Upper Limb Immobilisation: A Neural Plasticity Model with Relevance to Poststroke Motor Rehabilitation

Advances in our understanding of the neural plasticity that occurs after hemiparetic stroke have contributed to the formulation of theories of poststroke motor recovery. These theories, in turn, have underpinned contemporary motor rehabilitation strategies for treating motor deficits after stroke, such as upper limb hemiparesis. However, a relative drawback has been that, in general, these strategies are most compatible with the recovery profiles of relatively high-functioning stroke survivors and therefore do not easily translate into benefit to those individuals sustaining low-functioning upper limb hemiparesis, who otherwise have poorer residual function. For these individuals, alternative motor rehabilitation strategies are currently needed. In this paper, we will review upper limb immobilisation studies that have been conducted with healthy adult humans and animals. Then, we will discuss how the findings from these studies could inspire the creation of a neural plasticity model that is likely to be of particular relevance to the context of motor rehabilitation after stroke. For instance, as will be elaborated, such model could contribute to the development of alternative motor rehabilitation strategies for treating poststroke upper limb hemiparesis. The implications of the findings from those immobilisation studies for contemporary motor rehabilitation strategies will also be discussed and perspectives for future research in this arena will be provided as well.

Transcranial magnetic stimulation for evaluation of motor cortical excitability in restless legs syndrome/Willis-Ekbom disease

There is no consensus about mechanisms underlying restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED). Cortical excitability may be abnormal in RLS. Transcranial magnetic stimulation (TMS) can provide insight about cortical excitability. We reviewed studies about measures of excitability to TMS in RLS. Original studies published between January 1999 and January 2015 were searched in PubMed, Scopus, and Web of Science databases. Inclusion criteria were as follows: original studies involving primary RLS in patients from both sexes and ages between 18 and 85 years; TMS protocols clearly described; and they were written in English, in peer-reviewed journals. Fifteen manuscripts were identified. TMS protocols were heterogeneous across studies. Resting motor threshold, active motor threshold, and amplitudes of motor-evoked potentials were typically reported to be normal in RLS. A reduction in short-interval intracortical inhibition (SICI) was the most consistent finding, whereas conflicting results were described in regard to short-interval intracortical facilitation and the contralateral silent period. Decreased SICI can be reversed by treatment with dopaminergic agonists. Plasticity in the motor cortex and sensorimotor integration may be disrupted. TMS may become a useful biomarker of responsiveness to drug treatment in RLS. The field can benefit from increases in homogeneity and sizes of samples, as well as from decrease in methodological variability across studies.

Effects of somatosensory stimulation on corticomotor excitability in patients with unilateral cerebellar infarcts and healthy subjects - preliminary results

Background

In healthy humans, somatosensory stimulation in the form of 2 h-repetitive peripheral afferent nerve stimulation (SS) increases excitability of the contralateral motor cortex. In this preliminary study, we explored effects of SS on excitability to transcranial magnetic stimulation (TMS) in patients with unilateral cerebellar infarcts and age-matched controls.

Methods

Ten patients with infarcts in one cerebellar hemisphere and six age-matched controls participated in the study. Each subject participated in one session of active, and one session of sham SS delivered to the median nerve ipsilateral to the cerebellar infarct in patients, and to the homologous nerve in controls. Before and after each session, the following TMS measures were performed: resting motor threshold (rMT), motor evoked potentials (MEPs), short-interval intracortical inhibition (SICI) and short-interval intracortical facilitation (SICF). Amplitudes of motor evoked potentials were normalized to amplitudes of supramaximal M responses (MEP/M ratios).

Results

In the control group, there was a significant increase in rMT, and a significant increase in MEP/M ratios after active, but not after sham SS. There were no significant differences in rMT or MEP/M ratios in the group of patients after active or sham SS. There were no significant differences in SICI or SICF after active or sham SS in either group.

Conclusion

Consistent with results reported in rodents, these preliminary findings suggest for the first time in humans, that normal cerebellar activity is required so that SS can modulate excitability of the sensorimotor cortex.

Corticospinal tract integrity and lesion volume play different roles in chronic hemiparesis and its improvement through motor practice

BACKGROUND

Initial evidence suggests that the integrity of the ipsilesional corticospinal tract (CST) after stroke is strongly related to motor function in the chronic state but not the treatment gain induced by motor rehabilitation.

OBJECTIVE

We examined the association of motor status and treatment benefit by testing patients with a wide range of severity of hemiparesis of the left and right upper extremity.

METHOD

Diffusion tensor imaging was performed in 22 patients beyond 12 months after onset of stroke with severe to moderate hemiparesis. Motor function was tested before and after 2 weeks of modified constraint-induced movement therapy.

RESULTS

CST integrity, but not lesion volume, correlated with the motor ability measures of the Wolf Motor Function Test and the Motor Activity Log. No differences were found between left and right hemiparesis. Motor performance improved significantly with the treatment regime, and did so equally for patients with left and right arm paresis. However, treatment benefit was not associated with either CST integrity or lesion volume.

CONCLUSION

CST integrity correlated best in this small trial with chronic long-term status but not treatment-induced improvements. The CST may play a different role in the mechanisms mediating long-term outcome compared to those underlying practice-induced gains after a chronic plateau in motor function.