Clinical Research Directory

Effect of Visual Retraining on Visual Loss Following Visual Cortical Damage

This project is intended to collect data using standard clinical tests and psychophysics to quantify the effect of visual cortical damage on the structure of the residual visual system, visual perception, spatial awareness, and brain function. The investigators will also assess the effect of intensive visual retraining on the residual visual system, processing of visual information and the use of such information in real-world situations following damage. This research is intended to improve our understanding of the consequences of permanent visual system damage in humans, of methods that can be used to reverse visual loss, and of brain mechanisms by which visual recovery is achieved.

Vision Loss Impact on Navigation in Virtual Reality

The purpose of this research is to better understand the impact of cortically-induced blindness (CB) and the compensatory strategies subjects with this condition may develop on naturalistic behaviors, specifically, driving. Using a novel Virtual Reality (VR) program, the researchers will gather data on steering behavior in a variety of simulated naturalistic environments. Through the combined use of computer vision, deep learning, and gaze-contingent manipulations of the visual field, this work will test the central hypothesis that changes to visually guided steering behaviors in CB are a consequence of changes to the visual sampling and processing of task-related motion information (i.e., optic flow).

Validation of Early Prognostic Data for Recovery Outcome After Stroke for Future, Higher Yield Trials

VERIFY will validate biomarkers of upper extremity (UE) motor outcome in the acute ischemic stroke window for immediate use in clinical trials, and explore these biomarkers in acute intracerebral hemorrhage. VERIFY will create the first multicenter, large-scale, prospective dataset of clinical, transmagnetic stimulation (TMS), and MRI measures in the acute stroke time window.

PRecisiOn Medicine In StrokE: Evolution of Plasma Brain-Derived Tau in Acute Stroke

The investigators recently identified Brain-derived tau (BD-tau) as a sensitive blood-based biomarker for brain injury in acute ischemic stroke: in patients with acute ischemic stroke, plasma BD-tau was associated with imaging-based metrics of brain injury upon admission, increased within the first 24 hours in correlation with infarct progression, and at 24 hours was superior to final infarct volume in predicting 90-day functional outcome. While informing on the relation of BD-tau with imaging-based metrics of brain injury, this cross-sectional study was restricted to BD-tau assessments upon admission and at day 2 and could not inform on key characteristics of the evolution of plasma BD-tau, including when exactly it starts to rise, how long it continues to rise, and how it is determined by infarct characteristics as well as comorbidities. Here, the investigators aim to assess plasma BD-tau every hour from admission to 48 hours after onset to evaluate the hypothesis that BD-tau rises immediately after onset and plateaus between three and 48 hours after onset.

Study of Circulating Monocytes in Patients With Ischemic Vascular Disease

The purpose of this research study is to discover the functions of circulating white blood cells, called monocytes, and associated circulating substances in heart attack and ischemic stroke patients. Ischemic Strokes (clots) occur as a result of an obstruction within a blood vessel supplying blood to the brain. A type of monocyte carrying a surface marker called "P2X4" helps the immune system sense and respond to danger signals from the body such as heart muscle and brain tissue injuries. The researchers expect to learn more about how these monocyte cells react to heart and brain tissue injury, and how the cells may then produce proteins or other chemical substances which promote the healing of heart muscle after heart attack and brain tissue after an ischemic stroke.

At-Home taVNS - Stroke Rehab

Early evidence suggests the benefits of post-stroke motor rehabilitation may be enhanced by applying electrical stimulation to the ear. This study aims to test the new approach of pairing ear stimulation with motor rehabilitation in the home setting in stroke survivors with upper limb motor function deficits.

Prevention of Infection of the Respiratory Tract Through Application of Non-Invasive Methods of Secretion Suctioning

Adults who are unconscious or severely ill and need a breathing tube connected to a ventilator are at high risk of developing a lung infection (pneumonia) within the first few days in the intensive care unit. This early pneumonia affects up to 30 to 50 % of certain high-risk patients, prolongs the time on the ventilator and in hospital, and increases the use of antibiotics. Two strategies are commonly used today to try to prevent this infection: a short, three-day course of an intravenous antibiotic, and removal of secretions from the airway with a sterile suction catheter. Both have limitations - antibiotics can favour the growth of resistant bacteria, and catheter suctioning is uncomfortable and may injure the airway. PIRÁMIDES is a small (60-patient) pilot study that compares the current practice with two non-invasive, mechanical alternatives for keeping the airway clear: a continuous low-pressure suction system built into a special breathing tube, and a device that produces a gentle, programmed "artificial cough" through the ventilator. Adult patients who are intubated for severe trauma, severe brain injury, stroke, resuscitated cardiac arrest or other causes of decreased consciousness are randomly assigned, in equal numbers, to one of the three approaches and followed for 14 days, with a final visit at day 90. The main goal is to find out which of the three strategies best prevents early pneumonia, and which provides the best overall result for patients when survival, severity of infection, need for additional antibiotics and side effects are considered together. To make these comparisons as fair as possible in an open-label study, an independent committee of doctors not involved in patient care reviews each suspected pneumonia case without knowing which strategy the patient received. The results will help design a larger trial to confirm which approach is safest and most effective for preventing early pneumonia in critically ill patients on a ventilator.

Cognitive Strategies for Optimizing Brain Health And Managing Transgenerational Vascular Risk Factors Post-Stroke

People living with the cognitive effects of stroke are at risk for recurrent stroke and further cognitive decline. Also problematic is that stroke risk clusters in families and biological family members of people who have ischemic stroke may also be at increased risk of stroke and/or cognitive decline. The primary goal of this study is to test the feasibility of a virtually delivered cognitive strategy training and health coaching program to reduce vascular risk and promote brain health in persons with stroke and their biological family members.

Impact of COVID-19 Vaccines on Cerebrovascular Health

Safe and effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines may reduce the transmission of and achieve population immunity against the COVID-19 pandemic, which accounted for more than 3.75million deaths worldwide. With World Health Organization's (WHO) effort on ensuring equitable access to COVID-19 vaccines, vaccination rate may increase in the near future. On the other hand, vaccination hesitancy has emerged as a major hindrance on the global vaccination campaigns in certain areas due to safety concerns, social factors, and public health policies. For instance, a recent survey conducted in Hong Kong showed a low vaccine acceptance rate of 37%. Long-term safety concerns and post-vaccination events relayed by the social media maybe reasons for vaccination hesitancy. Among which, cerebrovascular accidents (CVA) after vaccination were one of the most frequently reported post-vaccination events. These reports ranged from ischemic strokes in elderly patients with multiple cardiovascular co-morbidities, to hemorrhage strokes in otherwise "young-and-fit" adults. While many of these events were investigated by the COVID-19 immunization expert committee, an important premise to address the apprehension of CVA after vaccination is the provision of evidence-based information of the impact of COVID-19 vaccines on brain health. In this prospective, longitudinal, observational study, we aim to elucidate the relationship between COVID-19 vaccines and cerebrovascular health in healthy citizens in a population-based cohort.

Glenzocimab for REperfusion in the Setting of Endovascular Therapy for Brain infarctioN: GREEN Study

Emergent reperfusion is the main goal for acute ischemic stroke therapy (AIS). Endovascular therapy (EVT) is recommended within 6 hrs of stroke onset, and up to 24 hrs following perfusion imaging criteria. Despite the major benefit associated with MT, more than 50% of the patients remain disabled at 3 months. Reperfusion rates after MT are critical to determine functional outcome. However, complete reperfusion is obtained in only 50 % of the patients, due to, at least in part, erratic emboli and/or no-reflow processes. The aim of this study is to evaluate the efficacy of glenzocimab in addition to EVT and compared to EVT plus placebo, whether or not associated with ntravenous thrombolysis (IVT), on functional outcome at day 90.

The REACTplusNMES Trial: A Double-blinded RCT

The aim of this study is to compare the effectiveness of 6-weeks of reactive balance training (REACT) with and without neuromuscular electrical stimulation (NMES) to paretic lower limb muscles on biomechanical, clinical, neuromuscular and neuroplastic outcomes of reactive balance control. This project is a Phase-I study and incorporates a double-blinded, randomized controlled trial design. Methods: Forty-six individuals with chronic stroke will be recruited and screened for determining their eligibility for the study. Once enrolled, they will be randomized into either of the two groups: intervention group (23 participants) and control group (23 participants). Both groups will undergo series of pre-training assessments which includes a postural disturbance in the form of a slip- or trip-like perturbations and walking tests in laboratory environment. After the pre-training assessment, individuals will undergo 6-weeks of training (2 hour per session, 2 sessions per week). The intervention group will receive NMES with the REACT training and the control group will receive ShamNMES. NMES will be applied to the different muscle groups of the paretic lower limb using an advanced software which is able to synchronize muscle activation with the time of perturbation onset and according to the phases of gait. After training, both groups will again be tested on all the assessments performed pre training. This study will help us understand the immediate therapeutic and mechanistic effects of REACT+NMES and inform stroke rehabilitation research and clinical practice. Our study will provide foundational evidence for future use of NMES to implement clinically applicable neuromodulation adjuvants to reactive balance training, which could be leveraged for designing more effective future interventions for fall-risk reduction.

HR-MRI-Directed Tirofiban Therapy for Late-Window Acute Ischemic Stroke (TIAN)

This study aims to address the existing clinical challenges by introducing high-resolution magnetic resonance vessel wall imaging (HR-MRI), an advanced imaging technology, to achieve precise etiological classification in patients with acute ischemic stroke (AIS) beyond the time window. HR-MRI allows clear visualization of intracranial arterial wall structures and direct identification of key pathological features of the culprit vessel, including atherosclerotic plaques, vascular wall remodeling, and intracranial hemorrhage, thereby enabling reliable differentiation between intracranial atherosclerotic large artery atherosclerosis (ICAS-LAA) stroke and other etiological subtypes such as cardiogenic embolism. Based on the latest clinical demands and advances in imaging technology, this study intends to evaluate the efficacy and safety of tirofiban in patients with ICAS-LAA stroke beyond the time window under the precise guidance of HR-MRI. It is expected to provide high-level evidence-based medical evidence for this specific patient population and further optimize clinical diagnosis and treatment strategies.

Visio-conference for Pre-hospital Triage of Stroke Suspicions

Interventionnal Study to investigate the accuracy of our clinical based algorithm performed by using a visioconference device to assess the eligibility of acute recanalisation treatment (intraveinous thrombolysis (IVT) and/or mechanical thrombectomie (TM). Clinical identification of type of treatment is needed is pre-hospital triage of these patients.

Urinary Disorders in Subacute Patients After Stroke

This observational study will address urinary disorders in subacute stroke patients. Patients without and with urinary disorders will be compared, and treatment outcome will be assessed among the latter.

The Fourth Left Atrial Appendage Occlusion Study

LAAOS-4 aims to determine if catheter-based endovascular left atrial appendage occlusion prevents ischemic stroke or systemic embolism in participants with atrial fibrillation, who remain at high risk of stroke, despite receiving ongoing treatment with oral anticoagulation.

Neurovascular Product Surveillance Registry

Post market surveillance registry

Validation of TriAGE+ for Predicting Stroke Risk in ED Patients Presenting With Dizziness

Ischemic cerebrovascular diseases originating from the brain's posterior circulation account for 20-25% of cases. Among patients diagnosed with cerebellar infarction, 10% present with isolated dizziness as their sole symptom. Notably, posterior circulation strokes and cerebellar infarcts are misdiagnosed 2 to 4 times more frequently than anterior circulation strokes. In 2017, Kuroda et al. developed the TriAGE+ score to assess stroke risk in patients presenting with dizziness. This study aims to externally validate the TriAGE+ score, focusing on its safety, applicability, and reliability in predicting cerebrovascular disease in the emergency department.

Coordinated, Collaborative, Comprehensive, Family-based, Integrated, Technology-enabled Stroke Care

Stroke is the 5th leading cause of death and the leading cause of adult disability in the United States (US). Stroke is a complex disease with multiple interacting risk factors (including genetic, high blood pressure and cholesterol, and lifestyle factors like smoking, diet, and exercise) that lead to initial and recurrent stroke. Up to 90% of stroke survivors have some functional deficit that impacts both physical and mental health.

Ischemic Conditioning Improves Walking Function Post Stroke

This innovative study will address scientific and clinical areas relatively unexplored in chronic stroke that could lead to greater recovery of walking. Ischemic Conditioning (IC) is a non-invasive, simple procedure that improves motor function, exercise performance and cardiovascular function in healthy controls, but it has never been applied to the stroke population. We postulate that IC enhances the recruitment of motoneurons and results in positive neural adaptations, improves vascular endothelial function and peripheral blood flow, and together these improvements result in an increased capacity to exercise and faster walking speed. Future studies will examine the effects of IC and traditional therapy at different time points of recovery post stroke, durability of IC, molecular mechanisms of neural and cardiovascular adaptation and the efficacy compared with other adjuncts.

Rescue Endovascular Therapy for Progressive Acute Mild Ischemic Stroke With Large Vascular Occlusion

Endovascular therapy (EVT) added on best medical management is currently recommended in acute large vascular occlusion (LVO) stroke patients with National Institutes of Health Stroke Scale (NIHSS) score \>5. Thus, a sizeable fraction of patients with a minor stroke that do not undergo cerebrovascular screening may experience an early neurological deterioration (END) due to LVO, possibly leading to poor long-term functional outcome. However, whether these patients may still benefit from a rescue EVT is unknown, especially in a late window (\>24 hours). In this study, the investigators assume that best medical management plus EVT might be superior than best medical management alone in a late window for minor stroke patients who have experienced an LVO and END. The primary objective of the study was to establish the safety and efficacy of EVT in a late window for minor stroke patients in the anterior circulation who experienced an LVO and END.

Assessment of Functional Efficiency of the Upper Limb After Stroke

The aim of the study will be to: conduct the process of cultural and linguistic adaptation of questionnaires for assessing the functional efficiency of the upper limb to the Polish version and to assess psychometric properties: reliability, validity and sensitivity to clinical changes among patients after stroke.

Effect of Remote Ischemic Preconditioning on Collaterals of Atherosclerosis Stroke

The goal of this clinical trial is to explore the influence of chronic RIC on collateral status evaluated by DSA in ischemic stroke patients with LAA etiology.

The Effect of InTensive Statin in Ischemic Stroke With inTracranial Atherosclerotic Plaques

Intracranial atherosclerotic disease is the most common cause of ischemic stroke that is directly attributed to the progression or rupture of intracranial high-risk plaque in Asia. Many studies mainly from Euro-American population with a focus on extracranial carotid plaque have fully demonstrated the advantages of intensive statin therapy on stabilizing or reversing plaque burden, reversing plaque composition presenting that lipid-rich necrotic core (LRNC) is gradually replaced by fibrous tissue, and even reversing pattern of arterial remodeling to reduce the occurrence of cerebrovascular events. Yet, direct evidence of the effect of intensive statin therapy on intracranial atherosclerotic plaques is lacking and the effect of statin intensity and duration on intracranial plaque burden and composition is still unclear. High resolution magnetic resonance imaging (HRMRI) is a new and non-invasive technique that enable to assess the morphologic characteristics of vascular wall and plaque composition of intracranial artery. Based on above discussion, the investigators conduct this study to further determine the effect of intensive statin in ischemic stroke with intracranial atherosclerotic plaques.

Low-Frequency REpetitive TRanscranial Magnetic Stimulation in ACute Ischemic StrokE Within 48 Hours

This is a multicenter, open-label, evaluator-blinded, investigator-initiated, randomized clinical trial, to evaluate the clinical efficacy and safety of LF-rTMS in reducing infarct size, reducing disability rate and improving functional outcome in patients with acute ischemic stroke within 48 hours after stroke onset.