Acute ischaemic stroke alters the brain’s preference for distinct dynamic connectivity states

Abstract Acute ischaemic stroke disturbs healthy brain organization, prompting subsequent plasticity and reorganization to compensate for the loss of specialized neural tissue and function. Static resting state functional MRI studies have already furthered our understanding of cerebral reorganization by estimating stroke-induced changes in network connectivity aggregated over the duration of several minutes. In this study, we used dynamic resting state functional MRI analyses to increase temporal resolution to seconds and explore transient configurations of motor network connectivity in acute stroke. To this end, we collected resting state functional MRI data of 31 patients with acute ischaemic stroke and 17 age-matched healthy control subjects. Stroke patients presented with moderate to severe hand motor deficits. By estimating dynamic functional connectivity within a sliding window framework, we identified three distinct connectivity configurations of motor-related networks. Motor networks were organized into three regional domains, i.e. a cortical, subcortical and cerebellar domain. The dynamic connectivity patterns of stroke patients diverged from those of healthy controls depending on the severity of the initial motor impairment. Moderately affected patients (n = 18) spent significantly more time in a weakly connected configuration that was characterized by low levels of connectivity, both locally as well as between distant regions. In contrast, severely affected patients (n = 13) showed a significant preference for transitions into a spatially segregated connectivity configuration. This configuration featured particularly high levels of local connectivity within the three regional domains as well as anti-correlated connectivity between distant networks across domains. A third connectivity configuration represented an intermediate connectivity pattern compared to the preceding two, and predominantly encompassed decreased interhemispheric connectivity between cortical motor networks independent of individual deficit severity. Alterations within this third configuration thus closely resembled previously reported ones originating from static resting state functional MRI studies post-stroke. In summary, acute ischaemic stroke not only prompted changes in connectivity between distinct networks, but it also caused characteristic changes in temporal properties of large-scale network interactions depending on the severity of the individual deficit. These findings offer new vistas on the dynamic neural mechanisms underlying acute neurological symptoms, cortical reorganization and treatment effects in stroke patients.

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Acute ischemic stroke alters the brain’s preference for distinct dynamic connectivity states

10.1101/19011031 ◽

2019 ◽

Cited By ~ 1

Author(s):

Anna K. Bonkhoff ◽

Flor A. Espinoza ◽

Harshvardhan Gazula ◽

Victor M. Vergara ◽

Lukas Hensel ◽

...

Keyword(s):

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Resting State ◽

Network Connectivity ◽

Resting State Fmri ◽

Cortical Reorganization ◽

Connectivity Pattern ◽

Healthy Controls ◽

Stroke Patients ◽

Dynamic Connectivity

AbstractAcute ischemic stroke disturbs healthy brain organization, prompting subsequent plasticity and reorganization to compensate for loss of specialized neural tissue and function. Static resting-state functional magnetic resonance imaging (fMRI) studies have already furthered our understanding of cerebral reorganization by estimating stroke-induced changes in network connectivity aggregated over the duration of several minutes. In this study, we utilized dynamic resting-state fMRI analyses to increase temporal resolution to seconds and explore transient configurations of motor network connectivity in acute stroke. To this end, we collected resting-state fMRI data of 31 acute ischemic stroke patients and 17 age-matched healthy controls. Stroke patients presented with moderate to severe hand motor deficits. By estimating dynamic connectivity within a sliding window framework, we identified three distinct connectivity configurations of motor-related networks. Motor networks were organized into three regional domains, i.e. a cortical, subcortical and cerebellar domain. Temporal connectivity patterns of stroke patients markedly diverged from those of healthy controls depending on the severity of the initial motor impairment. Moderately affected patients (n=18) spent significantly more time in a weakly connected configuration that was characterized by low levels of connectivity, both locally as well as between distant regions. In contrast, severely affected patients (n=13) showed a significant preference for transitions into a spatially segregated connectivity configuration. This configuration featured particularly high levels of local connectivity within the three regional domains as well as anti-correlated connectivity between distant networks across domains. A third connectivity configuration represented an intermediate connectivity pattern compared to the preceding two, and predominantly encompassed decreased inter-hemispheric connectivity between cortical motor networks independent of individual deficit severity. Alterations within this third configuration thus closely resembled previously reported ones originating from static resting-state fMRI studies post-stroke.In summary, acute ischemic stroke not only prompted changes in connectivity between distinct functional networks, yet also caused severe aberrations in temporal properties of large-scale network interactions depending on the individual deficit severity. These findings offer new vistas on the dynamic neural mechanisms underlying acute neurological symptoms, cortical reorganization and treatment effects in stroke patients.

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Total perfusion-diffusion mismatch detected using resting-state functional MRI

BJR|case reports ◽

10.1259/bjrcr.20210056 ◽

2021 ◽

pp. 20210056

Author(s):

Ahmed Khalil ◽

Kian Röhrs ◽

Christian H Nolte ◽

Ivana Galinovic

Keyword(s):

Contrast Agent ◽

Ischaemic Stroke ◽

Young Patient ◽

Functional Mri ◽

Acute Ischaemic Stroke ◽

Perfusion Imaging ◽

Resting State ◽

Imaging Technique ◽

Cerebellar Stroke

Total perfusion-diffusion mismatch is a well-recognised phenomenon in patients with acute ischaemic stroke. We describe a case of total perfusion-diffusion mismatch detected using an emerging contrast-agent-free perfusion imaging technique in a young patient with acute cerebellar stroke.

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DETERMINING STROKE ONSET TIME USING QUANTIATIVE MRI: PRELIMINARY EVIDENCE OF AN ADC/QT2 MISMATCH IN ACUTE ISCHAEMIC STROKE PATIENTS

10.26226/morressier.58e389b1d462b802923850c8 ◽

2017 ◽

Author(s):

Bryony McGarry

Keyword(s):

Ischaemic Stroke ◽

Acute Ischaemic Stroke ◽

Onset Time ◽

Preliminary Evidence ◽

Stroke Onset ◽

Stroke Patients

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A physiological perspective of the associations between hydration status and CTP neuroimaging parameters in hyper‐acute ischaemic stroke patients

Clinical Physiology and Functional Imaging ◽

10.1111/cpf.12690 ◽

2021 ◽

Author(s):

Alex Buoite Stella ◽

Miloš Ajčević ◽

Giovanni Furlanis ◽

Carlo Lugnan ◽

Marina Gaio ◽

...

Keyword(s):

Ischaemic Stroke ◽

Acute Ischaemic Stroke ◽

Hydration Status ◽

Stroke Patients

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Mechanical thrombectomy in acute ischaemic stroke patients with pre-interventional intracranial haemorrhage following intravenous thrombolysis

The Neuroradiology Journal ◽

10.1177/19714009211009112 ◽

2021 ◽

pp. 197140092110091

Author(s):

Hanna Styczen ◽

Matthias Gawlitza ◽

Nuran Abdullayev ◽

Alex Brehm ◽

Carmen Serna-Candel ◽

...

Keyword(s):

Clinical Outcome ◽

Ischaemic Stroke ◽

Acute Ischaemic Stroke ◽

Intracranial Haemorrhage ◽

Mechanical Thrombectomy ◽

Intravenous Thrombolysis ◽

Modified Rankin Scale ◽

Large Vessel Occlusion ◽

Stroke Patients ◽

Vessel Occlusion

Background Data on outcome of endovascular treatment in patients with acute ischaemic stroke due to large vessel occlusion suffering from intravenous thrombolysis-associated intracranial haemorrhage prior to mechanical thrombectomy remain scarce. Addressing this subject, we report our multicentre experience. Methods A retrospective analysis of consecutive acute ischaemic stroke patients treated with mechanical thrombectomy due to large vessel occlusion despite the pre-interventional occurrence of intravenous thrombolysis-associated intracranial haemorrhage was performed at five tertiary care centres between January 2010–September 2020. Baseline demographics, aetiology of stroke and intracranial haemorrhage, angiographic outcome assessed by the Thrombolysis in Cerebral Infarction score and clinical outcome evaluated by the modified Rankin Scale at 90 days were recorded. Results In total, six patients were included in the study. Five individuals demonstrated cerebral intraparenchymal haemorrhage on pre-interventional imaging; in one patient additional subdural haematoma was observed and one patient suffered from isolated subarachnoid haemorrhage. All patients except one were treated by the ‘drip-and-ship’ paradigm. Successful reperfusion was achieved in 4/6 (67%) individuals. In 5/6 (83%) patients, the pre-interventional intracranial haemorrhage had aggravated in post-interventional computed tomography with space-occupying effect. Overall, five patients had died during the hospital stay. The clinical outcome of the survivor was modified Rankin Scale=4 at 90 days follow-up. Conclusion Mechanical thrombectomy in patients with intravenous thrombolysis-associated intracranial haemorrhage is technically feasible. The clinical outcome of this subgroup of stroke patients, however, appears to be devastating with high mortality and only carefully selected patients might benefit from endovascular treatment.

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Obesity in acute ischaemic stroke patients treated with intravenous thrombolysis therapy

Neurological Research ◽

10.1080/01616412.2021.1939486 ◽

2021 ◽

pp. 1-8

Author(s):

Hongmin Li ◽

Suliman Khan ◽

Rabeea Siddique ◽

Qian Bai ◽

Yang Liu ◽

...

Keyword(s):

Ischaemic Stroke ◽

Acute Ischaemic Stroke ◽

Intravenous Thrombolysis ◽

Stroke Patients ◽

Thrombolysis Therapy

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Resting-state functional MRI language network connectivity differences in patients with brain tumors: exploration of the cerebellum and contralesional hemisphere

Brain Imaging and Behavior ◽

10.1007/s11682-021-00498-5 ◽

2021 ◽

Author(s):

Nicholas S. Cho ◽

Kyung K. Peck ◽

Madeleine N. Gene ◽

Mehrnaz Jenabi ◽

Andrei I. Holodny

Keyword(s):

Brain Tumors ◽

Functional Mri ◽

Resting State ◽

Network Connectivity ◽

Language Network

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Abstract W P29: Tissue Plasminogen Activator Mediated Reperfusion, and Subsequent Improvement in Resting State Connectivity Correlates with Functional Outcome in Acute Ischemic Stroke Patients

Stroke ◽

10.1161/str.46.suppl_1.wp29 ◽

2015 ◽

Vol 46 (suppl_1) ◽

Author(s):

Souvik Sen ◽

Johann Fridriksson ◽

Taylor Hanayik ◽

Christopher Rorden ◽

Isabel Hubbard ◽

...

Keyword(s):

Ischemic Stroke ◽

Functional Connectivity ◽

Functional Outcome ◽

Resting State ◽

Network Connectivity ◽

Stroke Patients ◽

Post Stroke ◽

Resting State Network ◽

Tissue Plasminogen

Background: Intravenous Tissue Plasminogen Activator (TPA) is the only FDA approved medical therapy for acute ischemic stroke (AIS). Prior study suggests that early recanalization is associated with better stroke outcome. Our aim was to correlate task-negative and task-positive (TN/TP) resting state network activity with tissue perfusion and functional outcome, in stroke patients who received TPA. Method: AIS patients were consented and underwent NIH stroke scale (NIHSS) assessment and magnetic resonance imaging (MRI) scans during TPA infusion (baseline) and six hours post stroke. The MRI sequences include contrast-enhanced perfusion weighted image (PWI) and resting state Blood Oxygen Level-Dependent or BOLD (RSB) images acquired using a Siemens Treo 3T MRI scanner. Additionally, the RSB scan and the NIHSS were obtained at a 30-day follow up visit. Results: Fourteen patients (mean age ± SD=63 ±14, 50% male, 50% white, 43% black and 7% others) who qualified for TPA completed the study at baseline and 6 hours post stroke. Of these, 6 patients had valid follow up data at 30 days. Three patients without cerebral ischemia were excluded. A paired samples t-test comparing baseline and 6h post stroke showed a significantly improved TP network t(10)= -4.24 p< 0.05. The resting network connectivity improved from 6 hours post stroke to 30-days follow up, t(5)= -5.35 p< 0.01. Similarly, NIHSS, at 6h post stroke t(10)= 3.62 p< 0.01 and at 30-days follow up t(5)= -3.4 p< 0.01 were significantly better than the NIHSS at baseline. The 6-hours post-stroke perfusion correlated with the resting network connectivity in both the damaged (r=-0.56 p= 0.07) and intact hemispheres (r= -0.57 p= 0.06). Differences in functional connectivity and NIHSS scores from baseline to 6 h were positively correlated (r= 0.56 p=0.07). Conclusion: In this pilot study we found that TPA led to changes in MRI based resting state networks and associated functional outcome. Correlations were found between perfusion, functional connectivity and NIHSS. This suggests that the improvement of resting state network means improved efficiency of brain activity indicated by functional outcome and may be a potential predictive MRI biomarker for TPA response. A larger study is needed to verify this finding.

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