Investigating the Working Mechanism of Transcranial Direct Current Stimulation.

Background: Transcranial direct current stimulation (tDCS) is used to modulate neuronal activity, but the exact mechanism of action (MOA) is unclear. This study investigates tDCS-induced modulation of the corticospinal excitability and the underlying MOA. By anesthetizing the scalp before applying tDCS and by stimulating the cheeks, we investigated whether stimulation of peripheral and/or cranial nerves contributes to the effects of tDCS on corticospinal excitability.

Increased Dentate Gyrus Excitability in the Intrahippocampal Kainic Acid Mouse Model for Temporal Lobe Epilepsy.

The intrahippocampal kainic acid (IHKA) mouse model is an extensively used in vivo model to investigate the pathophysiology of mesial temporal lobe epilepsy (mTLE) and to develop novel therapies for drug-resistant epilepsy. It is characterized by profound hippocampal sclerosis and spontaneously occurring seizures with a major role for the injected damaged hippocampus, but little is known about the excitability of specific subregions. The purpose of this study was to electrophysiologically characterize the excitability of hippocampal subregions in the chronic phase of the induced epilepsy in the IHKA mouse model.

Deep Brain Stimulation of the Anterior Nucleus of the Thalamus in Drug-Resistant Epilepsy in the MORE Multicenter Patient Registry.

Background And Objectives: The efficacy of deep brain stimulation of the anterior nucleus of the thalamus (ANT DBS) in patients with drug-resistant epilepsy (DRE) was demonstrated in the double-blind Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy randomized controlled trial. The Medtronic Registry for Epilepsy (MORE) aims to understand the safety and longer-term effectiveness of ANT DBS therapy in routine clinical practice.

Methods: MORE is an observational registry collecting prospective and retrospective clinical data.

Ex Vivo Feedback Control of Neurotransmission Using a Photocaged Adenosine A1 Receptor Agonist.

We report the design, synthesis, and validation of the novel compound photocaged N-cyclopentyladenosine (cCPA) to achieve precisely localized and timed release of the parent adenosine A1 receptor agonist CPA using 405 nm light. G protein-coupled A receptors (ARs) modulate neurotransmission via pre- and post-synaptic routes. The dynamics of the CPA-mediated effect on neurotransmission, characterized by fast activation and slow recovery, make it possible to implement a closed-loop control paradigm.

Recent Advances in the Use of Focused Ultrasound as a Treatment for Epilepsy.

Epilepsy affects about 1% of the population. Approximately one third of patients with epilepsy are drug-resistant (DRE). Resective surgery is an effective treatment for DRE, yet invasive, and not all DRE patients are suitable resective surgery candidates.

Collateral status and recanalization after endovascular treatment for acute ischemic stroke.

Background: Successful recanalization and good collateral status are associated with good clinical outcomes after endovascular treatment (EVT) for acute ischemic stroke, but the relationships among them are unclear.

Objective: To assess if collateral status is associated with recanalization after EVT and if collateral status modifies the association between successful recanalization and functional outcome.

Methods: We retrospectively analyzed data from the MR CLEAN Registry, a multicenter prospective cohort study of patients with a proximal anterior occlusion who underwent EVT in the Netherlands.

Improvements in Endovascular Treatment for Acute Ischemic Stroke: A Longitudinal Study in the MR CLEAN Registry.

Background: We evaluated data from all patients in the Netherlands who underwent endovascular treatment for acute ischemic stroke in the past 3.5 years, to identify nationwide trends in time to treatment and procedural success, and assess their effect on clinical outcomes.

Methods: We included patients with proximal occlusions of the anterior circulation from the second and first cohorts of the MR CLEAN (Multicenter Randomized Clinical trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry (March 2014 to June 2016; June 2016 to November 2017, respectively).

Intracranial carotid artery calcification subtype and collaterals in patients undergoing endovascular thrombectomy.

Background And Aims: Distinct subtypes of intracranial carotid artery calcification (ICAC) have been found (i.e., medial and intimal), which may differentially be associated with the formation of collaterals.

Seizures and Interictal Epileptiform Activity in the Rat Collagenase Model for Intracerebral Hemorrhage.

Aims: Intracerebral hemorrhage (ICH) is a known risk factor for the development of acute symptomatic as well as late unprovoked seizures. The underlying pathophysiology of post-ICH seizures is incompletely understood and there are no reliable predictive biomarkers. An animal model to study post-ICH seizures is currently lacking.

Long-term chemogenetic suppression of seizures in a multifocal rat model of temporal lobe epilepsy.

Objective: One third of epilepsy patients do not become seizure-free using conventional medication. Therefore, there is a need for alternative treatments. Preclinical research using designer receptors exclusively activated by designer drugs (DREADDs) has demonstrated initial success in suppressing epileptic activity.

7T versus 3T MR Angiography to Assess Unruptured Intracranial Aneurysms.

Background And Purpose: Aneurysm size and neck measurements are important for treatment decisions. The introduction of 7T magnetic resonance angiography (MRA) led to new possibilities assessing aneurysm morphology and flow due to the higher signal-to-noise ratio. However, it is unknown if the size measurements on 7T MRA are similar to those on the standard 3T MRA.

Presentation outside office hours does not negatively influence treatment times for reperfusion therapy for acute ischemic stroke.

Background: Treatment outside office hours has been associated with increased workflow times for intravenous thrombolysis (IVT) in acute ischemic stroke (AIS). Limited data suggest that this "off-hours effect" also exists for endovascular treatment (EVT). We investigated this phenomenon in a well-organized acute stroke care region in the Netherlands.

Acute symptomatic seizures following intracerebral hemorrhage in the rat collagenase model.

Background And Purpose: Intracerebral hemorrhage (ICH) is a known risk factor for the development of seizures, but little is known about the pathophysiology of seizures in the acute phase post-ICH and their influence on functional outcome. With the use of an animal model, the underlying pathophysiology could be further unraveled. The aim of our study was to optimize the rat collagenase stroke model for the detection of acute symptomatic seizures using video-EEG monitoring.

Identification of vagus nerve stimulation parameters affecting rat hippocampal electrophysiology without temperature effects.

Background: Recent experiments in rats have demonstrated significant effects of VNS on hippocampal excitability but were partially attributed to hypothermia, induced by the applied VNS parameters.

Objective: To allow meaningful preclinical research on the mechanisms of VNS and translation of rodent results to clinical VNS trials, we aimed to identify non-hypothermia inducing VNS parameters that significantly affect hippocampal excitability.

Methods: VNS was administered in cycles of 30 s including either 0.

Deep brain stimulation reduces evoked potentials with a dual time course in freely moving rats: Potential neurophysiological basis for intermittent as an alternative to continuous stimulation.

Objective: Deep brain stimulation (DBS) is an increasingly applied treatment for various neuropsychiatric disorders including drug-resistant epilepsy, and it may be optimized by rationalizing the stimulation protocol based on increased knowledge of its mechanism of action. We evaluated the effects of minutes to hours of hippocampal DBS on hippocampal evoked potentials (EPs) and local field potentials (LFPs) in freely moving male rats to further investigate some of the previously proposed mechanisms of action.

Methods: Hippocampal high-frequency (130 Hz) DBS was administered for 0, 1, or 6 min every 10 min for 160 min.

Clinical and Imaging Determinants of Collateral Status in Patients With Acute Ischemic Stroke in MR CLEAN Trial and Registry.

Background and Purpose- Collateral circulation status at baseline is associated with functional outcome after ischemic stroke and effect of endovascular treatment. We aimed to identify clinical and imaging determinants that are associated with collateral grade on baseline computed tomography angiography in patients with acute ischemic stroke due to an anterior circulation large vessel occlusion. Methods- Patients included in the MR CLEAN trial (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; n=500) and MR CLEAN Registry (n=1488) were studied.

A systematic review and meta-analysis of Woven EndoBridge single layer for treatment of intracranial aneurysms.

Background And Purpose: The Woven EndoBridge is an intrasaccular device for the treatment of intracranial aneurysms. The first generation consisted of a high-profile double-layer braid. This review aims to evaluate the outcomes of the new generation low-profile Woven EndoBridge single layer device for intracranial aneurysm treatment.

Current Hospital Demographics of Subarachnoid Hemorrhage Based on CT Angiography and 3D Rotational Angiography in a Neurosurgical Center.

Background And Purpose: Aneurysmal subarachnoid hemorrhage is an important cause of mortality and morbidity. Modern hospital demographics are scarce. We evaluated the diagnosis and treatment of patients with SAH in a neurosurgical referral center.

Biotinidase deficiency: A treatable cause of opticospinal syndrome in young adults.

Diagnosis of biotinidase deficiency is rare and usually made in infancy, through newborn screening or after presenting symptoms. We present the case of 19-year old male with progressive optic atrophy and in a second phase spinal cord syndrome unresponsive to immunosuppressive therapies. After diagnosis of profound biotinidase deficiency, oral biotin substitution was started with partial visual improvement and normalization of gait.

Hypothermia Masks Most of the Effects of Rapid Cycling VNS on Rat Hippocampal Electrophysiology.

Vagus nerve stimulation (VNS) modulates hippocampal dentate gyrus (DG) electrophysiology and induces hypothermia in freely moving rats. This study evaluated whether hippocampal (CA1) electrophysiology is similarly modulated and to what extent this is associated with VNS-induced hypothermia. Six freely moving rats received a first 4h session of rapid cycling VNS (7s on/18s off), while CA1 evoked potentials, EEG and core temperature were recorded.

Impact of single phase CT angiography collateral status on functional outcome over time: results from the MR CLEAN Registry.

Background: Collateral status modified the effect of endovascular treatment (EVT) for stroke in several randomized trials. We assessed the association between collaterals and functional outcome in EVT treated patients and investigated if this association is time dependent.

Methods: We included consecutive patients from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN) Registry (March 2014-June 2016) with an anterior circulation large vessel occlusion undergoing EVT.

[Cranial computed tomography, lumbar puncture and clinical deterioration in bacterial meningitis: a nationwide cohort study].

Background: Investigate how often cerebral herniation occurs following lumbar puncture (LP) in patients with bacterial meningitis, and whether cranial computed tomography (CT) can be used to identify patients at a higher risk of cerebral herniation.

Study Design: Prospective, nationwide cohort study covering the period March 2006 - November 2014.

Method: We identified patients with community-acquired bacterial meningitis who showed signs of clinical deterioration, possibly caused by LP.

Association of Time From Stroke Onset to Groin Puncture With Quality of Reperfusion After Mechanical Thrombectomy: A Meta-analysis of Individual Patient Data From 7 Randomized Clinical Trials.

Importance: Reperfusion is a key factor for clinical outcome in patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT) for large-vessel intracranial occlusion. However, data are scarce on the association between the time from onset and reperfusion results.

Objective: To analyze the rate of reperfusion after EVT started at different intervals after symptom onset in patients with AIS.

The use of the PSH-AM in patients with diffuse axonal injury and autonomic dysregulation: A cohort study and review.

Purpose: 1) To determine the clinical expression and consequences of autonomic dysregulation in patients with diffuse axonal injury (DAI), and 2) to study the use of the "paroxysmal sympathetic hyperactivity assessment measure" (PSH-AM).

Methods: Patients clinically diagnosed with autonomic dysregulation were selected from a cohort involving 116 patients with DAI. We studied the incidence of autonomic features, treatment, and outcome.