Air Pollution Particulate Matter Exposure and Chronic Cerebral Hypoperfusion and Measures of White Matter Injury in a Murine Model.

Background: Exposure to ambient air pollution particulate matter (PM) is associated with increased risk of dementia and accelerated cognitive loss. Vascular contributions to cognitive impairment are well recognized. Chronic cerebral hypoperfusion (CCH) promotes neuroinflammation and blood-brain barrier weakening, which may augment neurotoxic effects of PM.

The Rist radial access system: a multicenter study of 152 patients.

Background: Transradial access (TRA) for neurointervention is becoming increasingly popular as experience with the technique grows. Despite reasonable efficacy using femoral catheters off-label, conversion to femoral access occurs in approximately 8.6-10.

Somatic mosaicism in the MAPK pathway in sporadic brain arteriovenous malformation and association with phenotype.

Objective: Sporadic brain arteriovenous malformation (BAVM) is a tangled vascular lesion characterized by direct artery-to-vein connections that can cause life-threatening intracerebral hemorrhage (ICH). Recently, somatic mutations in KRAS have been reported in sporadic BAVM, and mutations in other mitogen-activated protein kinase (MAPK) signaling pathway genes have been identified in other vascular malformations. The objectives of this study were to systematically evaluate somatic mutations in MAPK pathway genes in patients with sporadic BAVM lesions and to evaluate the association of somatic mutations with phenotypes of sporadic BAVM severity.

Neuromodulation via Focal Radiation: Radiomodulation Update.

When radiation is focally delivered to brain tissue at sub-ablative doses, neural activity may be altered. When done at a specific brain circuit node or connection, this is referred to as "radiomodulation." Radiation-induced effects on brain tissue, basic science, and clinical research that supports the radiomodulation hypothesis are reviewed in this article.

Parent Vessel Occlusion via the Balloon-Assisted, Dual Microcatheter Technique.

Endovascular parent vessel sacrifice is an established technique used to treat vascular pathology and tumor infiltration of blood vessels. In high-flow vessels, such as the carotid artery or vertebral artery, distal coil migration and embolization are concerns. A method to mitigate this risk would improve the safety profile of the procedure.

Carotid artery occlusion and revascularization in the management of meningioma.

As the carotid artery courses through the skull base and into the subarachnoid space, it lies in close proximity to regions notorious for meningioma growth. Although infrequent, the growth of these tumors can compromise blood flow through the artery, putting the downstream territory at risk for stroke. In other scenarios, removal of these tumors sometimes requires planning to accomplish both tumor removal and revascularization in the same procedure when then the tumor invades the artery.

Failure of Flow Diverter Therapy: Predictors and Management Strategies.

Flow diversion is a safe and effective treatment for many types of brain aneurysms. Even so, there remain some aneurysms that persist despite initial treatment. In studies with the longest follow-up (5 yr), at least 5% of aneurysms persist with this treatment modality.

Comparison of predictive grading systems for procedural risk in endovascular treatment of brain arteriovenous malformations: analysis of 104 consecutive patients.

Objective: Several grading systems for procedural risk in the endovascular treatment of brain arteriovenous malformations (AVMs) have been proposed, including the Buffalo, Puerto Rico, and AVM embocure scoring systems. The authors sought to validate these systems in an independent patient cohort and compare each system to the established Spetzler-Martin (SM) scale.

Methods: One hundred four consecutive patients underwent adjunctive endovascular embolization of brain AVMs between 2002 and 2016 with the goal of reducing the surgical or hemorrhagic risk before definitive radiosurgical treatment.

The Continued Role and Value of Imaging for Acute Ischemic Stroke.

Advances in neuroimaging in the last 2 decades have revolutionized the management of acute ischemic stroke (AIS). Here we review the development of computed tomography (CT) and magnetic resonance imaging (MRI) modalities used to guide treatment of patients with AIS characterized by large vessel occlusion. In particular, we highlight recent randomized trials and their patient selection methodologies to detail the progression of these selection paradigms.

Pharmacogenomic considerations for antiplatelet agents: the era of precision medicine in stroke prevention and neurointerventional practice.

Antiplatelet drugs are widely utilized in the setting of primary stroke prevention, secondary stroke prevention, and neuroendovascular device-related stroke prevention. These medications are effective in general, although significant variability in drug activity exists between patients. Although this variation may be related in part to a multitude of factors, a growing body of evidence suggests that individual genotypes are a main contributor.

Mutations in Chromatin Modifier and Ephrin Signaling Genes in Vein of Galen Malformation.

Normal vascular development includes the formation and specification of arteries, veins, and intervening capillaries. Vein of Galen malformations (VOGMs) are among the most common and severe neonatal brain arterio-venous malformations, shunting arterial blood into the brain's deep venous system through aberrant direct connections. Exome sequencing of 55 VOGM probands, including 52 parent-offspring trios, revealed enrichment of rare damaging de novo mutations in chromatin modifier genes that play essential roles in brain and vascular development.

Identification of a rare pathway mutation in a non-syndromic human brain arteriovenous malformation via exome sequencing.

Brain arteriovenous malformations (AVMs) are abnormal connections between arteries and veins that can result in hemorrhagic stroke. A genetic basis for AVMs is suspected, and we investigated potential mutations in a 14-year-old girl who developed a recurrent brain AVM. Whole-exome sequencing (WES) of AVM lesion tissue and blood was performed accompanied by modeling, protein expression observation in lesion tissue and zebrafish modeling.

Surgical management of superior petrosal sinus dural arteriovenous fistulae with dominant internal carotid artery supply.

Background While technological advances have improved the efficacy of endovascular techniques for tentorial dural arteriovenous fistulae (DAVF), superior petrosal sinus (SPS) DAVF with dominant internal carotid artery (ICA) supply frequently require surgical intervention to achieve a definitive cure. Methods To compare the angiographic and clinical outcomes of endovascular and surgical interventions in patients with SPS DAVF, the records of all patients with tentorial DAVF from August 2010 to November 2015 were reviewed. Results Within this cohort, eight patients with nine SPS DAVF were eligible for evaluation.

Reductions in brain pericytes are associated with arteriovenous malformation vascular instability.

OBJECTIVEBrain arteriovenous malformations (bAVMs) are rupture-prone tangles of blood vessels with direct shunting of blood flow between arterial and venous circulations. The molecular and/or cellular mechanisms contributing to bAVM pathogenesis and/or destabilization in sporadic lesions have remained elusive. Initial insights into AVM formation have been gained through models of genetic AVM syndromes.

Neuroprotective strategies following intraparenchymal hemorrhage.

Intracerebral hemorrhage and, more specifically, intraparenchymal hemorrhage, are devastating disease processes with poor clinical outcomes. Primary injury to the brain results from initial hematoma expansion while secondary hemorrhagic injury occurs from blood-derived products such as hemoglobin, heme, iron, and coagulation factors that overwhelm the brains natural defenses. Novel neuroprotective treatments have emerged that target primary and secondary mechanisms of injury.

Selective embolization of ruptured feeding artery aneurysm followed by resection of arteriovenous malformation.

This is the case of a man in his 40s who suffered sudden collapse into a deep coma as a result of a ruptured arteriovenous malformation (AVM) feeding artery aneurysm within the lateral ventricle. The ruptured aneurysm was successfully treated with Onyx embolization of the feeding pedicle. The AVM and the feeding artery aneurysm were then removed via a transcallosal approach.

Contralateral transcallosal resection of a ventricular body arteriovenous malformation: 3D operative video.

A 46-year-old male presented with an incidentally discovered left ventricular body arteriovenous malformation (AVM). It measured 2 cm in diameter and had drainage via an atrial vein into the internal cerebral vein (Spetzler-Martin Grade III, Supplementary Grade 4). Preoperative embolization of the posterior medial choroidal artery reduced nidus size by 50%.