Consultation Requests and Satisfaction with a Telehealth Network for Epilepsy: Longitudinal Analysis of the Epilepsy Network Hessen Evaluation.

Telemedicine improves access to specialized medical expertise, as required for paroxysmal disorders. The Epilepsy Network Hessen Evaluation (ENHE) is a pilot cross-sectoral teleconsultation network connecting primary neurologists and pediatricians with epilepsy centers in Hessen, a federal German state. We prospectively and longitudinally evaluated telehealthcare in the ENHE.

Ischemic Lesion Location Based on the ASPECT Score for Risk Assessment of Neurogenic Dysphagia.

Dysphagia is common in patients with middle cerebral artery (MCA) infarctions and associated with malnutrition, pneumonia, and mortality. Besides bedside screening tools, brain imaging findings may help to timely identify patients with swallowing disorders. We investigated whether the Alberta stroke program early CT score (ASPECTS) allows for the correlation of distinct ischemic lesion patterns with dysphagia.

Flat Panel Computed Tomography Pooled Blood Volume and Infarct Prediction in Endovascular Stroke Treatment.

Background and Purpose- Patients with large-vessel stroke frequently need to be transferred to comprehensive stroke centers for endovascular treatment. An update of physiological perfusion parameters and stroke progression on arrival is desirable. We examined the reliability of preinterventional pooled blood volume (PBV)-maps acquired by flat-panel detector computed tomography (CT) in the interventional angiography suite.

Signal variance-based collateral index in DSC perfusion: A novel method to assess leptomeningeal collateralization in acute ischaemic stroke.

As a determinant of the progression rate of the ischaemic process in acute large-vessel stroke, the degree of collateralization is a strong predictor of the clinical outcome after reperfusion therapy and may influence clinical decision-making. Therefore, the assessment of leptomeningeal collateralization is of major importance. The purpose of this study was to develop and evaluate a quantitative and observer-independent method for assessing leptomeningeal collateralization in acute large-vessel stroke based on signal variance characteristics in T2*-weighted dynamic susceptibility contrast (DSC) perfusion-weighted MR imaging (PWI).

Impact of Lesion Load Thresholds on Alberta Stroke Program Early Computed Tomographic Score in Diffusion-Weighted Imaging.

Background And Aims: Assessment of ischemic lesions on computed tomography or MRI diffusion-weighted imaging (DWI) using the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is widely used to guide acute stroke treatment. However, it has never been defined how many voxels need to be affected to label a DWI-ASPECTS region ischemic. We aimed to assess the effect of various lesion load thresholds on DWI-ASPECTS and compare this automated analysis with visual rating.

Implementation of stroke teams and simulation training shortened process times in a regional stroke network-A network-wide prospective trial.

Background: To meet the requirements imposed by the time-dependency of acute stroke therapies, it is necessary 1) to initiate structural and cultural changes in the breadth of stroke-ready hospitals and 2) to find new ways to train the personnel treating patients with acute stroke. We aimed to implement and validate a composite intervention of a stroke team algorithm and simulation-based stroke team training as an effective quality initiative in our regional interdisciplinary neurovascular network consisting of 7 stroke units.

Methods: We recorded door-to-needle times of all consecutive stroke patients receiving thrombolysis at seven stroke units for 3 months before and after a 2 month intervention which included setting up a team-based stroke workflow at each stroke unit, a train-the-trainer seminar for stroke team simulation training and a stroke team simulation training session at each hospital as well as a recommendation to take up regular stroke team trainings.

The relationship between blood flow impairment and oxygen depletion in acute ischemic stroke imaged with magnetic resonance imaging.

Oxygenation-sensitive spin relaxation time T2' and relaxation rate R2' (1/T2') are presumed to be markers of the cerebral oxygen extraction fraction (OEF) in acute ischemic stroke. In this study, we investigate the relationship of T2'/R2' with dynamic susceptibility contrast-based relative cerebral blood flow (rCBF) in acute ischemic stroke to assess their plausibility as surrogate markers of the ischemic penumbra. Twenty-one consecutive patients with internal carotid artery and/or middle cerebral artery occlusion were studied at 3.

Oxygenation-Sensitive Magnetic Resonance Imaging in Acute Ischemic Stroke Using T2'/R2' Mapping: Influence of Relative Cerebral Blood Volume.

Background And Purpose: Quantitative T2'/R2' mapping detect locally increased concentrations of deoxygenated hemoglobin-causing a decrease of T2' and increase of R2'-and might reflect increased cerebral oxygen extraction fraction. Because increases of (relative) cerebral blood volume (rCBV) may influence T2' and R2' through accumulation of deoxygenated hemoglobin, we aimed to investigate the impact of rCBV on T2'/R2' in patients with ischemic stroke.

Methods: Data from patients with acute internal carotid artery and middle cerebral artery occlusion were analyzed.

Microfluidic coagulation assay for monitoring anticoagulant therapy in acute stroke patients.

Reliable detection of anticoagulation status in patients treated with non-vitamin K antagonist oral anticoagulants (NOACs) is challenging but of importance especially in the emergency setting. This study evaluated the potential of a whole-blood clotting time assay based on Surface Acoustic Waves (SAW-CT) in stroke-patients. The SAW-technology was used for quick and homogenous recalcification of whole blood inducing a surface-activated clotting reaction quantified and visualised by real-time fluorescence microscopy with automatic imaging processing.

T2-Imaging to Assess Cerebral Oxygen Extraction Fraction in Carotid Occlusive Disease: Influence of Cerebral Autoregulation and Cerebral Blood Volume.

Purpose: Quantitative T2'-mapping detects regional changes of the relation of oxygenated and deoxygenated hemoglobin (Hb) by using their different magnetic properties in gradient echo imaging and might therefore be a surrogate marker of increased oxygen extraction fraction (OEF) in cerebral hypoperfusion. Since elevations of cerebral blood volume (CBV) with consecutive accumulation of Hb might also increase the fraction of deoxygenated Hb and, through this, decrease the T2'-values in these patients we evaluated the relationship between T2'-values and CBV in patients with unilateral high-grade large-artery stenosis.

Materials And Methods: Data from 16 patients (13 male, 3 female; mean age 53 years) with unilateral symptomatic or asymptomatic high-grade internal carotid artery (ICA) or middle cerebral artery (MCA) stenosis/occlusion were analyzed.

Estimating the Quantitative Demand of NOAC Antidote Doses on Stroke Units.

Background: The first specific antidote for non-vitamin K antagonist oral anticoagulants (NOAC) has recently been approved. NOAC antidotes will allow specific treatment for 2 hitherto problematic patient groups: patients with oral anticoagulant therapy (OAT)-associated intracerebral hemorrhage (ICH) and maybe also thrombolysis candidates presenting on oral anticoagulation (OAT). We aimed to estimate the frequency of these events and hence the quantitative demand of antidote doses on a stroke unit.

Safety of endovascular treatment in acute stroke patients taking oral anticoagulants.

Background The endovascular treatment of acute cerebral ischemia has been proven beneficial without major safety concerns. To date, the role of endovascular treatment in patients treated with oral anticoagulants, which may be associated with periprocedural intracranial bleeding, remains uncertain. Aims The objective of the current analysis is to evaluate the safety of endovascular treatment in patients treated with oral anticoagulants.

Micro-optical prototyping of a surface acoustic wave-based point-of-care coagulation assay and first application in anticoagulated patients.

Objective: Clinicians demand for methods to monitor effects of direct anticoagulants in the emergency setting. We recently described a coagulation assay based on surface acoustic waves (SAW) technology, which quantifies anticoagulant effects by image processing. Here we describe the first step in miniaturizing this laboratory method and provide a portable prototype that contains the optical illumination and automatic on-board image processing.

Ischemic core and hypoperfusion volumes predict infarct size in SWIFT PRIME.

Objective: Within the context of a prospective randomized trial (SWIFT PRIME), we assessed whether early imaging of stroke patients, primarily with computed tomography (CT) perfusion, can estimate the size of the irreversibly injured ischemic core and the volume of critically hypoperfused tissue. We also evaluated the accuracy of ischemic core and hypoperfusion volumes for predicting infarct volume in patients with the target mismatch profile.

Methods: Baseline ischemic core and hypoperfusion volumes were assessed prior to randomized treatment with intravenous (IV) tissue plasminogen activator (tPA) alone versus IV tPA + endovascular therapy (Solitaire stent-retriever) using RAPID automated postprocessing software.

Quantitative T2, T2*, and T2' MR imaging in patients with ischemic leukoaraiosis might detect microstructural changes and cortical hypoxia.

Introduction: Quantitative MRI with T2, T2*, and T2' mapping has been shown to non-invasively depict microstructural changes (T2) and oxygenation status (T2* and T2') that are invisible on conventional MRI. Therefore, we aimed to assess whether T2 and T2' quantification detects cerebral (micro-)structural damage and chronic hypoxia in lesions and in normal appearing white matter (WM) and gray matter (GM) of patients with ischemic leukoaraiosis (IL). Measurements were complemented by the assessment of the cerebral blood flow (CBF) and the degree of GM and WM atrophy.

Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke.

Background: Among patients with acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, less than 40% regain functional independence when treated with intravenous tissue plasminogen activator (t-PA) alone. Thrombectomy with the use of a stent retriever, in addition to intravenous t-PA, increases reperfusion rates and may improve long-term functional outcome.

Methods: We randomly assigned eligible patients with stroke who were receiving or had received intravenous t-PA to continue with t-PA alone (control group) or to undergo endovascular thrombectomy with the use of a stent retriever within 6 hours after symptom onset (intervention group).

Collateral vessels in proximal middle cerebral artery occlusion: the ENDOSTROKE study.

Purpose: To determine the impact of collateral vessel status on clinical and imaging outcomes in patients undergoing endovascular therapy (EVT) for proximal middle cerebral artery (MCA) occlusion.

Materials And Methods: There were 160 patients with proximal MCA occlusion at six centers in this institutional review board-approved multicenter EVT registry. Angiograms were analyzed at a blinded core laboratory, and collateral vessel status was assessed by using the American Society of Interventional and Therapeutic Neuroradiology (ASITN)/Society of Interventional Radiology (SIR) collateral vessel grading system, while reperfusion was assessed by using the Thrombolysis in Cerebral Infarction (TICI) scale.

Acute stroke and obstruction of the extracranial carotid artery combined with intracranial tandem occlusion: results of interventional revascularization.

Purpose: Due to high thrombus load, acute stroke patients with tandem obstructions of the extra- and intracranial carotid arteries or the middle cerebral artery show a very limited response to systemic thrombolysis. Interventional treatment with mechanical thrombectomy-often in combination with acute stenting of underlying atherosclerotic stenosis or dissection-is increasingly used. It has been shown that such complex interventions are technically feasible.

Mechanical recanalization in basilar artery occlusion: the ENDOSTROKE study.

Objective: A study was undertaken to evaluate clinical and procedural factors associated with outcome and recanalization in endovascular stroke treatment (EVT) of basilar artery (BA) occlusion.

Methods: ENDOSTROKE is an investigator-initiated multicenter registry for patients undergoing EVT. This analysis includes 148 consecutive patients with BA occlusion, with 59% having received intravenous thrombolysis prior to EVT.

Changes of pH and energy state in subacute human ischemia assessed by multinuclear magnetic resonance spectroscopy.

Background And Purpose: In vivo changes in tissue pH and energy metabolism are key to understanding stroke pathophysiology. Our goal was to study pH changes in subacute ischemic stroke and their relation to energy metabolism, which, unlike acidosis in acute stroke, are not yet well understood.

Methods: We measured tissue pH and phospholipid as well as cell energy markers, including creatine, phosphocreatine, and N-acetyl-aspartate in subacute stroke with combined (1)H and (31)P magnetic resonance spectroscopy.

Validity of acute stroke lesion volume estimation by diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomographic Score depends on lesion location in 496 patients with middle cerebral artery stroke.

Background And Purpose: Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) has been used to estimate diffusion-weighted imaging (DWI) lesion volume in acute stroke. We aimed to assess correlations of DWI-ASPECTS with lesion volume in different middle cerebral artery (MCA) subregions and reproduce existing ASPECTS thresholds of a malignant profile defined by lesion volume ≥100 mL.

Methods: We analyzed data of patients with MCA stroke from a prospective observational study of DWI and fluid-attenuated inversion recovery in acute stroke.

Quantitative T2'-mapping in acute ischemic stroke.

Background And Purpose: Quantitative T2'-mapping detects regional changes in the relation of oxygenated and deoxygenated haemoglobine and might reflect areas with increased oxygen extraction. T2'-mapping in conjunction with an elaborate algorithm for motion correction was performed in patients with acute large-vessel stroke, and quantitative T2'-values were determined within the diffusion-weighted imaging lesion and perfusion-restricted tissue.

Methods: Eleven patients (median age, 71 years) with acute middle cerebral or internal carotid artery occlusion underwent MRI before scheduled endovascular treatment.

Frequency, risk of hemorrhage and treatment considerations for cerebral arteriovenous malformations with associated aneurysms.

Background: Data on arteriovenous malformations (AVMs) of the brain with AVM-associated aneurysms (AAA) are scarce. This study addresses the incidence, rate of hemorrhage, treatment strategies and stability during follow-up in a neurovascular center.

Methods: We retrospectively reviewed patients harboring an AVM with at least one AAA treated at our neurovascular center between 2002 and 2013.