A novel angiographic method to estimate arterial blood flow rates using contrast reflux: Effect of injection parameters.

Background: Contrast reflux, which is the retrograde movement of contrast against flow direction, is commonly observed during angiography. Despite a vast body of literature on angiography, the hemodynamic factors affecting contrast reflux have not been studied. Numerous methods have been developed to extract flow from angiography, but the reliability of these methods is not yet sufficient to be of routine clinical use.

Technical Success and Early Efficacy in 851 Patients with Saccular Intracranial Aneurysms: A Subset Analysis of SMART, a Prospective, Multicenter Registry Assessing the Embolization of Neurovascular Lesions using the Penumbra SMART COIL System.

Objective: The Prospective, Multicenter Registry Assessing the Embolization of Neurovascular Lesions Using the Penumbra SMART COIL® System (SMART) is the largest prospective, multicenter, postmarket registry established to gather real-world experience on Penumbra (Alameda, USA) SMART COIL System, PC400, and POD embolization coils. The goal of this study is to report the technical success and efficacy of SMART COIL System coils in treating saccular intracranial aneurysms.

Methods: This subgroup analysis from the SMART registry included patients with saccular intracranial aneurysms treated using ≥75% SMART COIL System or PC400 coils.

The SMART Registry: Long-Term Results on the Utility of the Penumbra SMART COIL System for Treatment of Intracranial Aneurysms and Other Malformations.

Penumbra SMART COIL® (SMART) System is a novel generation embolic coil with varying stiffness. The study purpose was to report real-world usage of the SMART System in patients with intracranial aneurysms (ICA) and non-aneurysm vascular lesions. The SMART Registry is a post-market, prospective, multicenter registry requiring ≥75% Penumbra Coils, including SMART, PC400, and/or POD coils.

An in vitro study of pressure increases during contrast injections in diagnostic cerebral angiography.

Background: During diagnostic cerebral angiography, the contrast bolus injected into a vessel can cause substantial changes in baseline pressures and flows. One potential, and serious complication is the re-rupture of aneurysms due to these injections. The goals of this in vitro study were to evaluate the effect of injection conditions on intraneurysmal pressure changes during angiography.

Stent-assisted coiling of cerebral aneurysms: multi-center analysis of radiographic and clinical outcomes in 659 patients.

Introduction: The endovascular stent-assisted coiling approach for the treatment of cerebral aneurysms is evolving rapidly with the availability of new stent devices. It remains unknown how each type of stent affects the safety and efficacy of the stent-coiling procedure.

Methods: This study compared the outcomes of endovascular coiling of cerebral aneurysms using Neuroform (NEU), Enterprise (EP), and Low-profile Visualized Intraluminal Support (LVIS) stents.

Angiographic assessment of the efficacy of flow diverter treatment for cerebral aneurysms.

Background: The recent growth of neuro-endovascular treatment has rekindled interest in the use of angiographic techniques for flow assessment. Aneurysm treatment with flow diverters is particularly amenable to such analysis. We analyze contrast time-density curves - recorded within aneurysms before (pre) and immediately after (post) flow diverter implantation to estimate six-month treatment outcomes.

Aspiration thrombectomy versus stent retriever thrombectomy as first-line approach for large vessel occlusion (COMPASS): a multicentre, randomised, open label, blinded outcome, non-inferiority trial.

Background: Stent retriever thrombectomy of large-vessel occlusion results in better outcomes than medical therapy alone. Alternative thrombectomy strategies, particularly a direct aspiration as first pass technique, while promising, have not been rigorously assessed for clinical efficacy in randomised trials. We designed COMPASS to assess whether patients treated with aspiration as first pass have non-inferior functional outcomes to those treated with a stent retriever as first line.

Hemodynamic Markers in the Anterior Circulation as Predictors of Recurrent Stroke in Patients With Intracranial Stenosis.

Background and Purpose- Although aggressive medical therapy was superior to stenting in the SAMMPRIS trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis), the stroke rate in the medical arm was still high. The aim of this study was to determine the association between hemodynamic markers (borderzone infarct pattern and impaired collateral flow on baseline imaging) and rates of recurrent stroke in patients treated medically in SAMMPRIS. Methods- This was a post hoc analysis of patients whose qualifying event for SAMMPRIS was an infarct in the territory of a stenotic middle cerebral artery or intracranial carotid artery.

In vitro measurement of the permeability of endovascular coils deployed in cerebral aneurysms.

Background And Purpose: Aneurysm recurrence is the primary limitation of endovascular coiling treatment for cerebral aneurysms. Coiling is currently quantified by a volumetric porosity measure called packing density (pd). Blood flow through a coil mass depends on the permeability of the coil mass, and not just its pd.

In vitro angiographic comparison of the flow-diversion performance of five neurovascular stents.

Background and purpose Data differentiating flow diversion properties of commercially available low- and high-porosity stents are limited. This in vitro study applies angiographic analysis of intra-aneurysmal flow to compare the flow-diversion performance of five neurovascular devices in idealized sidewall and bifurcation aneurysm models. Methods Five commercial devices (Enterprise, Neuroform, LVIS, FRED, and Pipeline) were implanted in silicone sidewall and bifurcation aneurysm models under physiological average flow of blood analog fluid.

Long-Term Clinical and Angiographic Outcomes Following Pipeline Embolization Device Treatment of Complex Internal Carotid Artery Aneurysms: Five-Year Results of the Pipeline for Uncoilable or Failed Aneurysms Trial.

Background: Early and mid-term safety and efficacy of aneurysm treatment with the Pipeline Embolization Device (PED) has been well demonstrated in prior studies.

Objective: To present 5-yr follow-up for patients treated in the Pipeline for Uncoilable or Failed Aneurysms clinical trial.

Methods: In our prospective, multicenter trial, 109 complex internal carotid artery (ICA) aneurysms in 107 subjects were treated with the PED.

Pipeline for uncoilable or failed aneurysms: 3-year follow-up results.

OBJECTIVE The long-term effectiveness of endovascular treatment of large and giant wide-neck aneurysms using traditional endovascular techniques has been disappointing, with high recanalization and re-treatment rates. Flow diversion with the Pipeline Embolization Device (PED) has been recently used as a stand-alone therapy for complex aneurysms, showing significant improvement in effectiveness while demonstrating a similar safety profile to stent-supported coil treatment. However, relatively little is known about its long-term safety and effectiveness.

Hemodynamics of Flow Diverters.

Cerebral aneurysms are pathological focal evaginations of the arterial wall at and around the junctions of the circle of Willis. Their tenuous walls predispose aneurysms to leak or rupture leading to hemorrhagic strokes with high morbidity and mortality rates. The endovascular treatment of cerebral aneurysms currently includes the implantation of fine-mesh stents, called flow diverters, within the parent artery bearing the aneurysm.

Acute Stroke Imaging Research Roadmap III Imaging Selection and Outcomes in Acute Stroke Reperfusion Clinical Trials: Consensus Recommendations and Further Research Priorities.

Background And Purpose: The Stroke Imaging Research (STIR) group, the Imaging Working Group of StrokeNet, the American Society of Neuroradiology, and the Foundation of the American Society of Neuroradiology sponsored an imaging session and workshop during the Stroke Treatment Academy Industry Roundtable (STAIR) IX on October 5 to 6, 2015 in Washington, DC. The purpose of this roadmap was to focus on the role of imaging in future research and clinical trials.

Methods: This forum brought together stroke neurologists, neuroradiologists, neuroimaging research scientists, members of the National Institute of Neurological Disorders and Stroke (NINDS), industry representatives, and members of the US Food and Drug Administration to discuss STIR priorities in the light of an unprecedented series of positive acute stroke endovascular therapy clinical trials.

The unruptured intracranial aneurysm treatment score: a multidisciplinary consensus.

Objective: We endeavored to develop an unruptured intracranial aneurysm (UIA) treatment score (UIATS) model that includes and quantifies key factors involved in clinical decision-making in the management of UIAs and to assess agreement for this model among specialists in UIA management and research.

Methods: An international multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 specialists was convened to develop and validate the UIATS model using a Delphi consensus. For internal (39 panel members involved in identification of relevant features) and external validation (30 independent external reviewers), 30 selected UIA cases were used to analyze agreement with UIATS management recommendations based on a 5-point Likert scale (5 indicating strong agreement).

Neuroophthalmological outcomes associated with use of the Pipeline Embolization Device: analysis of the PUFS trial results.

Object: Neuroophthalmological morbidity is commonly associated with large and giant cavernous and supraclinoid internal carotid artery (ICA) aneurysms. The authors sought to evaluate the neuroophthalmological outcomes after treatment of these aneurysms with the Pipeline Embolization Device (PED).

Methods: The Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial was an international, multicenter prospective trial evaluating the safety and efficacy of the PED.

A meta-analysis of prospective randomized controlled trials evaluating endovascular therapies for acute ischemic stroke.

Introduction: A recent randomized controlled trial (RCT), the Multicenter Randomized CLinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands (MR CLEAN), demonstrated better outcomes with endovascular treatment compared with medical therapy for acute ischemic stroke (AIS). However, previous trials have provided mixed results regarding the efficacy of endovascular treatment for AIS. A meta-analysis of all available trial data was performed to summarize the available evidence.

Evidence-based clinical practice for the neurointerventionalist.

The field of neurointerventional (NI) surgery has developed in the context of technologic innovation. Many treatments readily provided in 2014 would have been hard to imagine as recently as 10 years ago. The reality of present day NI care is that, while providers, payors, policy makers and patients rely on evidence to guide NI decision-making, the available data are often less robust than participants might desire.

A multicenter study of stent-assisted coiling of cerebral aneurysms with a Y configuration.

Background: Stent-assisted coiling with 2 stents in a Y configuration is a technique for coiling complex wide-neck bifurcation aneurysms.

Objective: We sought to provide long-term clinical and angiographic outcomes with Y-stent coiling, which are not currently established.

Methods: Seven centers provided deidentified, retrospective data on all consecutive patients who underwent stent-assisted coiling for an intracranial aneurysm with a Y-stent configuration.

IN VITRO QUANTIFICATION OF THE SIZE DISTRIBUTION OF INTRASACCULAR VOIDS LEFT AFTER ENDOVASCULAR COILING OF CEREBRAL ANEURYSMS.

Purpose: Endovascular coiling of cerebral aneurysms remains limited by coil compaction and associated recanalization. Recent coil designs which effect higher packing densities may be far from optimal because hemodynamic forces causing compaction are not well understood since detailed data regarding the location and distribution of coil masses are unavailable. We present an in vitro methodology to characterize coil masses deployed within aneurysms by quantifying intra-aneurysmal void spaces.

Physical factors effecting cerebral aneurysm pathophysiology.

Many factors that are either blood-, wall-, or hemodynamics-borne have been associated with the initiation, growth, and rupture of intracranial aneurysms. The distribution of cerebral aneurysms around the bifurcations of the circle of Willis has provided the impetus for numerous studies trying to link hemodynamic factors (flow impingement, pressure, and/or wall shear stress) to aneurysm pathophysiology. The focus of this review is to provide a broad overview of such hemodynamic associations as well as the subsumed aspects of vascular anatomy and wall structure.

Pipeline for uncoilable or failed aneurysms: results from a multicenter clinical trial.

Purpose: To evaluate the safety and effectiveness of the Pipeline Embolization Device (PED; ev3/Covidien, Irvine, Calif) in the treatment of complex intracranial aneurysms.

Materials And Methods: The Pipeline for Uncoilable or Failed Aneurysms is a multicenter, prospective, interventional, single-arm trial of PED for the treatment of uncoilable or failed aneurysms of the internal carotid artery. Institutional review board approval of the HIPAA-compliant study protocol was obtained from each center.

Thromboembolic events associated with endovascular treatment of cerebral aneurysms.

Objective: To evaluate the rate of peri-procedural thromboembolic events after the endovascular treatment of cerebral aneurysms. The rate of diffusion-positive lesions was assessed in relation to selected procedural and technical factors.

Methods: 184 patients treated with coil embolization (198 total procedures) between July 2004 and February 2007 were included.