Hyperglycemia, Risk of Subsequent Stroke, and Efficacy of Dual Antiplatelet Therapy: A Post Hoc Analysis of the POINT Trial

Background

One‐quarter of all strokes are subsequent events. It is not known whether higher levels of blood glucose are associated with an increased risk of subsequent stroke after high‐risk transient ischemic attack or minor ischemic stroke.

Methods and Results

We performed a secondary analysis of the POINT (Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke) trial to evaluate the relationship between serum glucose hyperglycemia (≥180 mg/dL) versus normoglycemia (<180 mg/dL) before enrollment in the trial and outcomes at 90 days. The primary end point was subsequent ischemic stroke modeled by a multivariable Cox model with adjustment for age, sex, race, ethnicity, study treatment assignment, index event, and key comorbidities. Of 4878 patients included in this study, 267 had a recurrent stroke. There was a higher hazard of subsequent stroke in patients with hyperglycemia compared with normoglycemia (adjusted hazard ratio [HR], 1.50 [95% CI, 1.05–2.14]). Treatment with dual antiplatelet therapy was not associated with a reduced hazard of subsequent stroke in patients with hyperglycemia (HR, 1.18 [95% CI, 0.69–2.03]), though the wide confidence interval does not exclude a treatment effect. When modeled as a continuous variable, there was evidence of a nonlinear association between serum glucose and the hazard of subsequent stroke (P<0.001).

Conclusions

Hyperglycemia on presentation is associated with an increased risk of subsequent ischemic stroke after high‐risk transient ischemic attack or minor stroke. A rapid, simple assay of serum glucose may be a useful biomarker to identify patients at particularly high risk of subsequent ischemic stroke.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT0099102.

Preventing Ischemic Cerebrovascular Events in High-Risk Patients With Non-disabling Ischemic Cerebrovascular Events Using Remote Ischemic Conditioning: A Single-Arm Study

Background: Secondary stroke prevention after a high-risk, non-disabling ischemic cerebrovascular event needs to be enhanced. The study was conducted to investigate whether remote ischemic conditioning (RIC) is effective in preventing recurrent ischemic events within 3 months.

Methods: This was a four-center, single-arm, open-label Phase IIa futility trial (PICNIC-One Study). Adult patients (≥18 years of age) who had an acute minor ischemic stroke (AMIS) with a National Institutes of Health Stroke Scale score ≤ 3 or a transient ischemic attack (TIA) with moderate-to-high risk of stroke recurrence (ABCD score ≥ 4) within 14 days of symptom onset were recruited. Patients received RIC as adjunctive therapy to routine secondary stroke prevention regimen. RIC consisted of five cycles of 5-min inflation (200 mmHg) and 5-min deflation of cuffs (45 min) on bilateral upper limbs twice a day for 90 days.

Results: A total of 285 patients met the study criteria, of which 167 provided signed informed consent and were enrolled. Data from 162 were analyzed with five subjects excluded. Recurrent AIS/TIA occurred in 6/162 (3.7%) patients within 3 months, with no occurrence of hemorrhagic stroke. The top three adverse events were upper limb pain (44/162, 27.2%), petechia (26/162, 16.0%), and heart palpitation (5/162, 3.1%). About 68 (42.0%) subjects completed ≥ 50% of 45-min RIC sessions.

Conclusions: RIC is a safe add-on procedure and it has a potential benefit in reducing recurrent cerebrovascular events in patients with high-risk, non-disabling ischemic cerebrovascular events as the risk of stroke/TIA events is lower than expected; however, its compliance needs to be improved. Our study provides critical preliminary data to plan a large sample size, randomized controlled clinical study to systematically investigate the safety and efficacy of RIC in this population.

Bridging thrombolysis in atrial fibrillation stroke is associated with increased hemorrhagic complications without improved outcomes

BACKGROUND

Atrial fibrillation (AF) associated ischemic stroke is associated with worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications after intravenous thrombolysis (IVT). Conversely, AF is not associated with hemorrhagic complications or functional outcomes in patients undergoing mechanical thrombectomy (MT). This differential effect of MT and IVT in AF associated stroke raises the question of whether bridging thrombolysis increases hemorrhagic complications in AF patients undergoing MT.

METHODS

This international cohort study of 22 comprehensive stroke centers analyzed patients with large vessel occlusion (LVO) undergoing MT between June 1, 2015 and December 31, 2020. Patients were divided into four groups based on comorbid AF and IVT exposure. Baseline patient characteristics, complications, and outcomes were reported and compared.

RESULTS

6461 patients underwent MT for LVO. 2311 (35.8%) patients had comorbid AF. In non-AF patients, bridging therapy improved the odds of good 90 day functional outcomes (adjusted OR (aOR) 1.29, 95% CI 1.03 to 1.60, p=0.025) and did not increase hemorrhagic complications. In AF patients, bridging therapy led to significant increases in symptomatic intracranial hemorrhage and parenchymal hematoma type 2 (aOR 1.66, 1.07 to 2.57, p=0.024) without any benefit in 90 day functional outcomes. Similar findings were noted in a separate propensity score analysis.

CONCLUSION

In this large thrombectomy registry, AF patients exposed to IVT before MT had increased hemorrhagic complications without improved functional outcomes, in contrast with non-AF patients. Prospective trials are warranted to assess whether AF patients represent a subgroup of LVO patients who may benefit from a direct to thrombectomy approach at thrombectomy capable centers.

Smaller spared subcortical nuclei are associated with worse post-stroke sensorimotor outcomes in 28 cohorts worldwide

Up to two-thirds of stroke survivors experience persistent sensorimotor impairments. Recovery relies on the integrity of spared brain areas to compensate for damaged tissue. Deep grey matter structures play a critical role in the control and regulation of sensorimotor circuits. The goal of this work is to identify associations between volumes of spared subcortical nuclei and sensorimotor behaviour at different timepoints after stroke. We pooled high-resolution T1-weighted MRI brain scans and behavioural data in 828 individuals with unilateral stroke from 28 cohorts worldwide. Cross-sectional analyses using linear mixed-effects models related post-stroke sensorimotor behaviour to non-lesioned subcortical volumes (Bonferroni-corrected, P < 0.004). We tested subacute (≤90 days) and chronic (≥180 days) stroke subgroups separately, with exploratory analyses in early stroke (≤21 days) and across all time. Sub-analyses in chronic stroke were also performed based on class of sensorimotor deficits (impairment, activity limitations) and side of lesioned hemisphere. Worse sensorimotor behaviour was associated with a smaller ipsilesional thalamic volume in both early (n = 179; d = 0.68) and subacute (n = 274, d = 0.46) stroke. In chronic stroke (n = 404), worse sensorimotor behaviour was associated with smaller ipsilesional putamen (d = 0.52) and nucleus accumbens (d = 0.39) volumes, and a larger ipsilesional lateral ventricle (d = -0.42). Worse chronic sensorimotor impairment specifically (measured by the Fugl-Meyer Assessment; n = 256) was associated with smaller ipsilesional putamen (d = 0.72) and larger lateral ventricle (d = -0.41) volumes, while several measures of activity limitations (n = 116) showed no significant relationships. In the full cohort across all time (n = 828), sensorimotor behaviour was associated with the volumes of the ipsilesional nucleus accumbens (d = 0.23), putamen (d = 0.33), thalamus (d = 0.33) and lateral ventricle (d = -0.23). We demonstrate significant relationships between post-stroke sensorimotor behaviour and reduced volumes of deep grey matter structures that were spared by stroke, which differ by time and class of sensorimotor measure. These findings provide additional insight into how different cortico-thalamo-striatal circuits support post-stroke sensorimotor outcomes.

Exploring optimal heart team protocol to improve decision-making stability for complex coronary artery disease: a sequential explanatory mixed method study

Background

Although heart team was recommended by guideline for decision-making in patients with complex coronary artery disease (CAD), the decision-making stability was lack of evaluation and optimal protocol remained unknown.

Purpose

We aimed to assess inter-team agreement for revascularization decision-making and related influencing factors, so as to provide recommendations for optimal protocol.

Methods

A sequential, explanatory mixed method study was conducted, including (1) a cross-sectional study retrospectively enrolling patients with complex CAD and four heart teams to assess the inter-team decision-making agreement and (2) a qualitative study that semi-structurally interviewed all heart team members to analyze the potential factors associated with decision-making discrepancy. Primary outcome was kappa value of inter-team decision-making agreement. Inductive thematic analysis was used to generate themes and subthemes attributing to decision-making discrepancy. Integrating qualitative and quantitative data, we explained how each subtheme affected decision-making agreement and provided corresponding recommendations based on these explanations. Finally, we provided a detailed heart team protocol by integrating our recommendations, published experience and guideline. Patient sample size was precalculated and interviewee sample size was identified by theoretical saturation.

Results

A total of 101 patients with complex CAD were randomly enrolled from a consecutive angiography registry. Sixteen specialists were invited and randomly established four heart teams to make decisions for enrolled patients. Inter-team decision-making agreement was moderate (kappa 0.582) (Table 1). Decision-making may be influenced at three themes (specialist quality; team composition; meeting process) and ten subthemes (decision thought; understanding of disease and evidence; understanding of other discipline; personality; learning curve; personnel quality; number of team members; discipline selection; ratio of different disciplines and meeting form). Recommendations at five levels were provided, including (1) specialist selection, (2) specialist training, (3) team composition, (4) team training and (5) meeting process. A detailed implementation protocol to establish and deploy a qualified heart team was generated.

Conclusions

Agreement between heart teams for revascularization decision-making in patients with complex CAD was moderate. Five recommendations to improve heart team modality were provided based on factors associated with decision-making discrepancy. A detailed heart team implementation protocol came into being. Randomized controlled trial was warranted to further confirm the protocol.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the national key research and development program;Beijing municipal commission of science and technology project Table 1. Inter-team agreement of decision making

Ipsilateral internal carotid artery web and acute ischemic stroke: A cohort study, systematic review and meta-analysis

Introduction

The carotid web is a compelling potential mechanism of embolic ischemic stroke. In this study, we aim to determine the prevalence of ipsilateral carotid web in a cohort of ischemic stroke patients and to perform a systematic review and meta-analysis of similar cohorts.

Patients & methods

We performed a retrospective, observational, cohort study of acute ischemic stroke patients admitted to a comprehensive stroke center from June 2012 to September 2017. Carotid web was defined on computed tomography angiography (CTA) as a thin shelf of non-calcified tissue immediately distal to the carotid bifurcation. We described the prevalence of carotid artery webs in our cohort, then performed a systematic review and meta-analysis of similar cohorts in the published literature.

Results

We identified 1,435 potentially eligible patients of whom 879 met criteria for inclusion in our analysis. An ipsilateral carotid web was detected in 4 out of 879 (0.45%) patients, of which 4/4 (1.6%) were in 244 patients with cryptogenic stroke and 3/4 were in 66 (4.5%) patients <60 years old with cryptogenic stroke. Our systematic review yielded 3,192 patients. On meta-analysis, the pooled prevalence of ipsilateral carotid web in cryptogenic stroke patients <60 was 13% (95% CI: 7%-22%; I² = 66.1%). The relative risk (RR) of ipsilateral versus contralateral carotid web in all patients was 2.5 (95% CI 1.5–4.2, p = 0.0009) whereas in patients less than 60 with cryptogenic stroke it was 3.0 (95% CI 1.6–5.8, p = 0.0011).

Discussion

Carotid webs are more common in young patients with cryptogenic stroke than in other stroke subtypes. Future studies concerning the diagnosis and secondary prevention of stroke associated with carotid web should focus on this population.

Improved robot-assisted laparoscopic telesurgery: feasibility of network converged communication

The converged transmission-assisted network communication architecture used in this study could meet the requirements of telesurgery, and effectively guarantee the security and immediacy of communication. With the security, flexibility, and universality of the network converged transmission, the clinical practical application of telesurgery and telemedicine would step up to a higher level.

Real-World Adherence to OnabotulinumtoxinA Treatment for Spasticity: Insights From the ASPIRE Study

OBJECTIVE

To identify baseline characteristics and treatment-related variables that affect adherence to onabotulinumtoxinA treatment from the Adult Spasticity International Registry (ASPIRE) study.

DESIGN

Prospective, observational registry (NCT01930786).

SETTING

International clinical sites.

PARTICIPANTS

Adults with spasticity (N=730).

INTERVENTIONS

OnabotulinumtoxinA at clinician's discretion.

MAIN OUTCOME MEASURES

Clinically meaningful thresholds used for treatment adherent (≥3 treatment sessions during 2-year study) and nonadherent (≤2 sessions). Data analyzed using logistic regression and presented as odds ratios (ORs) with 95% confidence intervals (CIs). Treatment-related variables assessed at sessions 1 and 2 only.

RESULTS

Of the total population, 523 patients (71.6%) were treatment adherent with 5.3±1.6 sessions and 207 (28.4%) were nonadherent with 1.5±0.5 sessions. In the final model (n=626/730), 522 patients (83.4%) were treatment adherent and 104 (16.6%) were nonadherent. Baseline characteristics associated with adherence: treated in Europe (OR=1.84; CI, 1.06-3.21; P=.030) and use of orthotics (OR=1.88; CI, 1.15-3.08; P=.012). Baseline characteristics associated with nonadherence: history of diplopia (OR=0.28; CI, 0.09-0.89; P=.031) and use of assistive devices (OR=0.51; CI, 0.29-0.90; P=.021). Treatment-related variables associated with nonadherence: treatment interval ≥15 weeks (OR=0.43; CI, 0.26-0.72; P=.001) and clinician dissatisfaction with onabotulinumtoxinA to manage pain (OR=0.18; CI, 0.05-0.69; P=.012). Of the population with stroke (n=411), 288 patients (70.1%) were treatment adherent with 5.3±1.6 sessions and 123 (29.9%) were nonadherent with 1.5±0.5 session. In the final stroke model (n=346/411), 288 patients (83.2%) were treatment adherent and 58 (16.8%) were nonadherent. Baseline characteristics associated with adherence: treated in Europe (OR=2.99; CI, 1.39-6.44; P=.005) and use of orthotics (OR=3.18; CI, 1.57-6.45; P=.001). Treatment-related variables associated with nonadherence: treatment interval ≥15 weeks (OR=0.42; CI, 0.21-0.83; P=.013) and moderate/severe disability on upper limb Disability Assessment Scale pain subscale (OR=0.40; CI, 0.19-0.83; P=.015).

CONCLUSIONS

These ASPIRE analyses demonstrate real-world patient and clinical variables that affect adherence to onabotulinumtoxinA and provide insights to help optimize management strategies to improve patient care.

Effects of Low-Frequency Repetitive Transcranial Magnetic Stimulation on Language Recovery in Poststroke Survivors With Aphasia: An Updated Meta-analysis

The effects of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) on treating poststroke aphasia (PSA) remain inconclusive. We aimed to evaluate the efficacy and safety of LF-rTMS on language function poststroke and determine potential factors that may affect treatment effects. Electronic databases, including MEDLINE, EMBASE, and Cochrane Library were searched to identify relevant randomized controlled trials (RCTs) concerning the effects of LF-rTMS on language performance poststroke. We adopted fixed- and random-effects models to estimate intervention effects, which were represented by the Hedges' g and 95% CIs. Subgroup analyses regarding several factors potentially influencing the effects of LF-rTMS on language recovery were also conducted. A total of 14 RCTs involving 374 participants were included in the meta-analysis. The pooled analysis showed the positive and significant effects of LF-rTMS on language function, both short-term (Hedges' g = 0.65; P < .05) and long-term (Hedges' g = 0.46; P < .05). Subgroup analyses demonstrated that LF-rTMS for 20 minutes per day over 10 days yielded the largest effect size (Hedges' g = 1.02; P < .05) and that LF-rTMS significantly improved language performance in the chronic stage after stroke (Hedges' g = 0.55; P < .05). Patients with different native languages might have diverse responses to LF-rTMS treatment efficacy. Additionally, there were significant improvements in language subtests, including naming, repetition, comprehension, and writing. Overall, this updated meta-analysis demonstrated that LF-rTMS has significant positive effects on PSA, with moderate treatment effects. It provides additional evidence to support LF-rTMS as a promising complementary therapy to promote language recovery in PSA.

Repetitive Transcranial Magnetic Stimulation on the Affected Hemisphere Enhances Hand Functional Recovery in Subacute Adult Stroke Patients: A Randomized Trial

Objectives: Either motor training or repetitive transcranial magnetic stimulation (rTMS) could modulate the neural plasticity after stroke. Therefore, synchronizing the two interventions may optimize the efficiency of recovery. In the present study, we aim to investigate the effect of rTMS along with hand grip training on the neurobehavioral and hand functional recovery in one cohort of subacute stroke patients. Methods: Thirty-nine stroke patients were enrolled in a single-center, single-blinded, randomized clinical trial. We tested different intervention effects of rTMS and hand grip training (group A), rTMS alone (group B), and hand grip training alone (group C). For the rTMS-treated groups, patients received 10 consecutive sessions of 5-Hz stimulation over the affected hemisphere with 750 pulses. Jebsen-Taylor Hand Function Test (JTHFT), Fugl-Meyer assessment of upper extremity (FMA-UE), grip strength, modified Barthel index (mBI), and ipsilesional motor evoked potential (iMEP) latency were assessed and compared across the groups. Results: We found that only rTMS along with hand grip training group all improved in JTHFT, FMA-UE, grip strength, and mBI (p ≤ 0.01) compared with the baseline among the three groups. Furthermore, this study demonstrated that rTMS plus hand grip training had much better results in improvement of neurobehavioral outcomes compared to the rTMS alone- and hand grip training alone-treated patients (p < 0.05). However, no significant differences were detected in neurophysiologic outcome between intra-groups and inter-groups (p > 0.05). Conclusion: These proof-of-concept results suggested that rTMS alone with hand grip training was a unique approach to promote hand functional recovery in stroke patients. It provided important information to design a large-scale multi-center clinical trial to further demonstrate the efficiency of the combination of central and peripheral stimulation. Clinical Trial Registration: http://www.chictr.org.cn (#ChiCTR1900023443).

Structural and Functional Imaging of the Retina in Central Retinal Artery Occlusion - Current Approaches and Future Directions

Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke which affects the retina. Intravenous thrombolysis is emerging as a compelling therapeutic approach. However, it is not known which patients may benefit from this therapy because there are no imaging modalities that adequately distinguish viable retina from irreversibly infarcted retina. The inner retina receives arterial supply from the central retinal artery and there is robust collateralization between this circulation and the outer retinal circulation, provided by the posterior ciliary circulation. Fundus photography can show canonical changes associated with CRAO including a cherry-red spot, arteriolar boxcarring and retinal pallor. Fluorescein angiography provides 2-dimensional imaging of the retinal circulation and can distinguish a complete from a partial CRAO as well as central versus peripheral retinal non-perfusion. Transorbital ultrasonography may assay flow through the central retinal artery and is useful in the exclusion of other orbital pathology that can mimic CRAO. Optical coherence tomography provides structural information on the different layers of the retina and exploratory work has described its utility in determining the time since onset of ischemia. Two experimental techniques are discussed. 1) Retinal functional imaging permits generation of capillary perfusion maps and can assay retinal oxygenation and blood flow velocity. 2) Photoacoustic imaging combines the principles of optical excitation and ultrasonic detection and - in animal studies - has been used to determine the retinal oxygen metabolic rate. Future techniques to determine retinal viability in clinical practice will require rapid, easily used, and reproducible methods that can be deployed in the emergency setting.

Direct Communication Between Brains: A Systematic PRISMA Review of Brain-To-Brain Interface

This paper aims to review the current state of brain-to-brain interface (B2BI) technology and its potential. B2BIs function via a brain-computer interface (BCI) to read a sender's brain activity and a computer-brain interface (CBI) to write a pattern to a receiving brain, transmitting information. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to systematically review current literature related to B2BI, resulting in 15 relevant publications. Experimental papers primarily used transcranial magnetic stimulation (tMS) for the CBI portion of their B2BI. Most targeted the visual cortex to produce phosphenes. In terms of study design, 73.3% (11) are unidirectional and 86.7% (13) use only a 1:1 collaboration model (subject to subject). Limitations are apparent, as the CBI method varied greatly between studies indicating no agreed upon neurostimulatory method for transmitting information. Furthermore, only 12.4% (2) studies are more complicated than a 1:1 model and few researchers studied direct bidirectional B2BI. These studies show B2BI can offer advances in human communication and collaboration, but more design and experiments are needed to prove potential. B2BIs may allow rehabilitation therapists to pass information mentally, activating a patient's brain to aid in stroke recovery and adding more complex bidirectionality may allow for increased behavioral synchronization between users. The field is very young, but applications of B2BI technology to neuroergonomics and human factors engineering clearly warrant more research.

Vagus nerve stimulation paired with rehabilitation for upper limb motor function after ischaemic stroke (VNS-REHAB): a randomised, blinded, pivotal, device trial

BACKGROUND

Long-term loss of arm function after ischaemic stroke is common and might be improved by vagus nerve stimulation paired with rehabilitation. We aimed to determine whether this strategy is a safe and effective treatment for improving arm function after stroke.

METHODS

In this pivotal, randomised, triple-blind, sham-controlled trial, done in 19 stroke rehabilitation services in the UK and the USA, participants with moderate-to-severe arm weakness, at least 9 months after ischaemic stroke, were randomly assigned (1:1) to either rehabilitation paired with active vagus nerve stimulation (VNS group) or rehabilitation paired with sham stimulation (control group). Randomisation was done by ResearchPoint Global (Austin, TX, USA) using SAS PROC PLAN (SAS Institute Software, Cary, NC, USA), with stratification by region (USA vs UK), age (≤30 years vs >30 years), and baseline Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score (20-35 vs 36-50). Participants, outcomes assessors, and treating therapists were masked to group assignment. All participants were implanted with a vagus nerve stimulation device. The VNS group received 0·8 mA, 100 μs, 30 Hz stimulation pulses, lasting 0·5 s. The control group received 0 mA pulses. Participants received 6 weeks of in-clinic therapy (three times per week; total of 18 sessions) followed by a home exercise programme. The primary outcome was the change in impairment measured by the FMA-UE score on the first day after completion of in-clinic therapy. FMA-UE response rates were also assessed at 90 days after in-clinic therapy (secondary endpoint). All analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, NCT03131960.

FINDINGS

Between Oct 2, 2017, and Sept 12, 2019, 108 participants were randomly assigned to treatment (53 to the VNS group and 55 to the control group). 106 completed the study (one patient for each group did not complete the study). On the first day after completion of in-clinic therapy, the mean FMA-UE score increased by 5·0 points (SD 4·4) in the VNS group and by 2·4 points (3·8) in the control group (between group difference 2·6, 95% CI 1·0-4·2, p=0·0014). 90 days after in-clinic therapy, a clinically meaningful response on the FMA-UE score was achieved in 23 (47%) of 53 patients in the VNS group versus 13 (24%) of 55 patients in the control group (between group difference 24%, 6-41; p=0·0098). There was one serious adverse event related to surgery (vocal cord paresis) in the control group.

INTERPRETATION

Vagus nerve stimulation paired with rehabilitation is a novel potential treatment option for people with long-term moderate-to-severe arm impairment after ischaemic stroke.

FUNDING

MicroTransponder.

Thrombolytic therapy for wake-up stroke: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

According to evidence-based clinical practice guidelines, patients presenting with disabling stroke symptoms should be treated with intravenous tissue plasminogen activator (IV tPA) within 4.5 h of time last known well. However, 25% of strokes are detected upon awakening (i.e., wake-up stroke [WUS]), which renders patients ineligible for IV tPA administered via time-based treatment algorithms, because it is impossible to establish a reliable time of symptom onset. We performed a systematic review and meta-analysis of the efficacy and safety of IV tPA compared with normal saline, placebo, or no treatment in patients with WUS using imaging-based treatment algorithms.

METHODS

We searched MEDLINE, Web of Science, and Scopus between January 1, 2006 and April 30, 2020. We included controlled trials (randomized or nonrandomized), observational cohort studies (prospective or retrospective), and single-arm studies in which adults with WUS were administered IV tPA after magnetic resonance imaging (MRI)- or computed tomography (CT)-based imaging. Our primary outcome was recovery at 90 days (defined as a modified Rankin Scale [mRS] score of 0-2), and our secondary outcomes were symptomatic intracranial hemorrhage (sICH) within 36 h, mortality, and other adverse effects.

RESULTS

We included 16 studies that enrolled a total of 14,017 patients. Most studies were conducted in Europe (37.5%) or North America (37.5%), and 1757 patients (12.5%) received IV tPA. All studies used MRI-based (five studies) or CT-based (10 studies) imaging selection, and one study used a combination of modalities. Sixty-one percent of patients receiving IV tPA achieved an mRS score of 0 to 2 at 90 days (95% confidence interval [CI]: 51%-70%, 12 studies), with a relative risk (RR) of 1.21 compared with patients not receiving IV tPA (95% CI: 1.01-1.46, four studies). Three percent of patients receiving IV tPA experienced sICH within 36 h (95% CI: 2.5%-4.1%; 16 studies), which is an RR of 4.00 compared with patients not receiving IV tPA (95% CI: 2.85-5.61, seven studies).

CONCLUSIONS

This systematic review and meta-analysis suggests that IV tPA is associated with a better functional outcome at 90 days despite the increased but acceptable risk of sICH. Based on these results, IV tPA should be offered as a treatment for WUS patients with favorable neuroimaging findings.

Effect of Low Intensity Transcranial Ultrasound Stimulation on Neuromodulation in Animals and Humans: An Updated Systematic Review

Background: Although low-intensity transcranial ultrasound stimulation (LI-TUS) has received more recognition for its neuromodulation potential, there remains a crucial knowledge gap regarding the neuromodulatory effects of LI-TUS and its potential for translation as a therapeutic tool in humans.

Objective: In this review, we summarized the findings reported by recently published studies regarding the effect of LI-TUS on neuromodulation in both animals and humans. We also aim to identify challenges and opportunities for the translation process.

Methods: A literature search of PubMed, Medline, EMBASE, and Web of Science was performed from January 2019 to June 2020 with the following keywords and Boolean operators: [transcranial ultrasound OR transcranial focused ultrasound OR ultrasound stimulation] AND [neuromodulation]. The methodological quality of the animal studies was assessed by the SYRCLE's risk of bias tool, and the quality of human studies was evaluated by the PEDro score and the NIH quality assessment tool.

Results: After applying the inclusion and exclusion criteria, a total of 26 manuscripts (24 animal studies and two human studies) out of 508 reports were included in this systematic review. Although both inhibitory (10 studies) and excitatory (16 studies) effects of LI-TUS were observed in animal studies, only inhibitory effects have been reported in primates (five studies) and human subjects (two studies). The ultrasonic parameters used in animal and human studies are different. The SYRCLE quality score ranged from 25 to 43%, with a majority of the low scores related to performance and detection bias. The two human studies received high PEDro scores (9/10).

Conclusion: LI-TUS appears to be capable of targeting both superficial and deep cerebral structures to modulate cognitive or motor behavior in both animals and humans. Further human studies are needed to more precisely define the effective modulation parameters and thereby translate this brain modulatory tool into the clinic.