Investigation of the need for an x-ray scatter-reduction grid during neurointerventional procedures.

X-ray guided neurointerventions are catheter-based treatments for cerebrovascular diseases such as strokes and aneurysms. During such procedures visualization of treatment devices is the primary imaging task. In this work we investigate the necessity of x-ray scatter-reduction grids in performing those tasks.

Assessment of an Artificial Intelligence Algorithm for Detection of Intracranial Hemorrhage.

Background: Immediate and accurate detection of intracranial hemorrhages (ICHs) is essential to provide a good clinical outcome for patients with ICH. Artificial intelligence has the potential to provide this, but the assessment of these methods needs to be investigated in depth. This study aimed to assess the ability of Canon's Stroke Solution ICH detection algorithm to accurately identify patients both with and without ICHs present.

Characterization of velocity patterns produced by pulsatile and constant flows using 1000 fps high-speed angiography (HSA).

In order to accurately quantify rapidly changing blood flow velocities, as typically seen in the neurovasculature, high temporal resolution is necessary. Current methods to extract velocity data from angiographic image sequences are generally limited to 30 fps or less. High-speed angiography (HSA) with a maximal frame rate of 1000 fps can be used to evaluate time-dependent flow details normally averaged out with lower frame rates.

Validation of an artificial intelligence-driven large vessel occlusion detection algorithm for acute ischemic stroke patients.

Rapid and accurate diagnosis of large vessel occlusions (LVOs) in acute ischemic stroke (AIS) patients using automated software could improve clinical workflow in determining thrombectomy in eligible patients. Artificial intelligence-based methods could accomplish this; however, their performance in various clinical scenarios, relative to clinical experts, must be thoroughly investigated. We aimed to assess the ability of Canon's Stroke Solution LVO application in properly detecting and locating LVOs in AIS patients.

Comaneci Device for Temporary Coiling Assistance for Treatment of Wide-Necked Aneurysms: Initial Case Series and Systematic Literature Review.

Background: Coiling of wide-necked aneurysms requires high-density packing of coils within the aneurysm, which necessitates adequate microcatheter access and navigability. The Comaneci device, introduced in the United States in 2019, is a retrievable stent that can be used as an adjunct to coiling of a wide-necked aneurysm without limiting flow. We present a case series and systematic review of use of this device.

POSITIVE: Perfusion imaging selection of ischemic stroke patients for endovascular therapy.

Background: The PerfusiOn imaging Selection of Ischemic sTroke patIents for endoVascular thErapy (POSITIVE) trial was designed to evaluate functional outcome in patients with emergent large vessel occlusion (ELVO) presenting within 0-12 hours with pre-specified bifurcated arms of early and late window presentation, who were selected for endovascular thrombectomy with non-vendor specific commercially available perfusion imaging software. Recent trials demonstrating the benefit of thrombectomy up to 16-24 hours following ELVO removed equipoise to randomize late window ELVO patients and therefore the trial was halted.

Methods: Up to 200 patients were to be enrolled in this FDA-cleared, prospective, randomized, multicenter international trial to compare thrombectomy and best medical management in patients with ELVO ineligible for or refractory to treatment with IV tissue plasminogen activator (IV-tPA) selected with perfusion imaging and presenting within 0-12 hours of last seen normal.

Radial first or patient first: a case series and meta-analysis of transradial versus transfemoral access for acute ischemic stroke intervention.

Background: Few studies have compared technical success and effectiveness of transradial access (TRA) versus transfemoral access (TFA) for mechanical thrombectomy (MT) for acute ischemic stroke (AIS). We compared the two approaches for technical success, effectiveness, and outcomes.

Methods: We retrospectively compared TRA with TFA for AIS MT at our institute.

Mapping access to endovascular stroke care in the USA and implications for transport models.

Background: The purpose of this cross-sectional study was to determine the percentage of the US population with 60 min ground or air access to accredited or state-designated endovascular-capable stroke centers (ECCs) and non-endovascular capable stroke centers (NECCs) and the percentage of NECCs with an ECC within a 30 min drive.

Methods: Stroke centers were identified and classified broadly as ECCs or NECCs. Geographic mapping of stroke centers was performed.

Complete flow control using transient concurrent rapid ventricular pacing or intravenous adenosine and afferent arterial balloon occlusion during transvenous embolization of cerebral arteriovenous malformations: case series.

Background: There are no reports that describe complete flow control using concurrent transient rapid ventricular pacing or intravenous (IV) adenosine and afferent arterial balloon flow arrest to aid transvenous embolization of cerebral arteriovenous malformations (AVM). We describe our experience with the use of this technique in patients undergoing transvenous AVM embolization.

Methods: Consecutive patients in whom transvenous embolization was attempted at our institute between January 2017 and July 2019 were included.

Investigation of convolutional neural networks using multiple computed tomography perfusion maps to identify infarct core in acute ischemic stroke patients.

To assess acute ischemic stroke (AIS) severity, infarct is segmented using computed tomography perfusion (CTP) software, such as RAPID, Sphere, and Vitrea, relying on contralateral hemisphere thresholds. Since this approach is potentially patient dependent, we investigated whether convolutional neural networks (CNNs) could achieve better performances without the need for contralateral hemisphere thresholds. CTP and diffusion-weighted imaging (DWI) data were retrospectively collected for 63 AIS patients.

Is Endovascular Therapy for Stroke Cost-Effective Globally? A Systematic Review of the Literature.

Objectives: Cost-effectiveness of endovascular therapy (EVT) is a key consideration for broad use of this approach for emergent large vessel occlusion stroke. We evaluated the evidence on cost-effectiveness of EVT in comparison with best medical management from a global perspective.

Materials And Methods: This systematic review of studies published between January 2010 and May 2020 evaluated the cost effectiveness of EVT for patients with large vessel occlusion acute ischemic stroke.

Rapid temporary coiling of the parent artery for the management of intraprocedural aneurysm rupture.

Intraprocedural rupture (IPR) of an intracranial aneurysm is the most feared complication of primary and stent-assisted coiling because it carries a high risk of morbidity and mortality. The endovascular strategy applied to control IPR depends on the cause of the rupture and stage of the procedure. Rupture during primary or stent-assisted coiling is traditionally managed with the use of continued packing, balloon microcatheter placement, or in rare cases, with parent artery sacrifice.

Endogenous animal models of intracranial aneurysm development: a review.

The pathogenesis and natural history of intracranial aneurysm (IA) remains poorly understood. To this end, animal models with induced cerebral vessel lesions mimicking human aneurysms have provided the ability to greatly expand our understanding. In this review, we comprehensively searched the published literature to identify studies that endogenously induced IA formation in animals.

Enhancing performance of a computed tomography perfusion software for improved prediction of final infarct volume in acute ischemic stroke patients.

Computed tomography perfusion (CTP) is crucial for acute ischemic stroke (AIS) patient diagnosis. To improve infarct prediction, enhanced image processing and automated parameter selection have been implemented in Vital Images' new CTP+ software. We compared CTP+ with its previous version, commercially available software (RAPID and Sphere), and follow-up diffusion-weighted imaging (DWI).

Patient-specific 3D-printed coronary models based on coronary computed tomography angiography volumes to investigate flow conditions in coronary artery disease.

Background: 3D printed patient-specific coronary models have the ability to enable repeatable benchtop experiments under controlled blood flow conditions. This approach can be applied to CT-derived patient geometries to emulate coronary flow and related parameters such as Fractional Flow Reserve (FFR).

Methods: This study uses 3D printing to compare such benchtop FFR results with a non-invasive CT-FFR research software algorithm and catheter based invasive FFR (I-FFR) measurements.

Use of quantitative angiographic methods with a data-driven model to evaluate reperfusion status (mTICI) during thrombectomy.

Purpose: Intra-procedural assessment of reperfusion during mechanical thrombectomy (MT) for emergent large vessel occlusion (LVO) stroke is traditionally based on subjective evaluation of digital subtraction angiography (DSA). However, semi-quantitative diagnostic tools which encode hemodynamic properties in DSAs, such as angiographic parametric imaging (API), exist and may be used for evaluation of reperfusion during MT. The objective of this study was to use data-driven approaches, such as convolutional neural networks (CNNs) with API maps, to automatically assess reperfusion in the neuro-vasculature during MT procedures based on the modified thrombolysis in cerebral infarction (mTICI) scale.

Endovascular management of radial artery loop for neuroangiography: Case series.

Background: Radial loops are rare congenital radial artery anomalies that may pose a significant challenge to successful transradial neuroangiography. In this case series, we describe the anatomy and frequency of radial artery loops and provide a technique for successful navigation of this anatomic anomaly.

Methods: We reviewed our database of radial diagnostic or interventional neuroangiographic procedures to identify cases in which a radial loop was encountered during the procedure.

Evaluation of Benefit and Cost Utility of Immediate Postanesthesia Care Unit Radiographs to Predict Airway Compromise After Anterior Cervical Discectomy and Fusion.

Study Design: Retrospective review.

Objective: Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure that may be complicated by airway compromise postoperatively. This life-threatening complication may necessitate reintubation and reoperation.

Proximal Internal Carotid artery Acute Stroke Secondary to tandem Occlusions (PICASSO) international survey.

Background: While mechanical thrombectomy (MT) is the standard of care for large vessel occlusion strokes, the optimal management of tandem occlusions (TO) remains uncertain. We aimed to determine the current practice patterns among stroke physicians involved in the treatment of TO during MT.

Methods: We distributed an online survey to neurovascular practitioners (stroke neurologists, neurointerventionalists, neurosurgeons, and radiologists), members of professional societies.

Landmark-Based Shape Analysis on Middle Cerebral Intracranial Aneurysms: A Geometric Morphometrics Approach to Infer Natural History.

Background: Due to the scarcity of longitudinal data, the morphologic development of intracranial aneurysms (IAs) during their natural history remains poorly understood. However, longitudinal information can often be inferred from cross-sectional datasets as demonstrated by anatomists' use of geometric morphometrics to build evolutionary trees, reconstructing species inter-relationships based on morphologic landmarks.

Objective: We adopted these tools to analyze cross-sectional image data and infer relationships between IA morphologies.

Increased Perviousness on CT for Acute Ischemic Stroke is Associated with Fibrin/Platelet-Rich Clots.

Background And Purpose: Clot perviousness in acute ischemic stroke is a potential CT imaging biomarker for mechanical thrombectomy efficacy. We investigated the association among perviousness, clot cellular composition, and first-pass effect.

Materials And Methods: In 40 mechanical thrombectomy-treated cases of acute ischemic stroke, we calculated perviousness as the difference in clot density on CT angiography and noncontrast CT.

Whole blood transcriptome biomarkers of unruptured intracranial aneurysm.

Background: The rupture of an intracranial aneurysm (IA) causes devastating subarachnoid hemorrhages, yet most IAs remain undiscovered until they rupture. Recently, we found an IA RNA expression signature of circulating neutrophils, and used transcriptome data to build predictive models for unruptured IAs. In this study, we evaluate the feasibility of using whole blood transcriptomes to predict the presence of unruptured IAs.

Coil Occlusion of Right M2 Fusiform Aneurysm After Balloon-Test Occlusion: 2-Dimensional Video.

We present a 73-year-old man with an incidental right M2 fusiform aneurysm demonstrating growth on serial noninvasive imaging over 5 years (Video 1). After multidisciplinary conference review, the decision was to proceed with intracranial balloon-test occlusion (BTO) followed by coil occlusion if the patient passed this test or by trap and bypass if the patient failed this test. With the patient under moderate conscious sedation, a transfemoral 8F approach was used with positioning of a TracStar 95-cm 088 guide catheter (Imperative Care, Campbell, California, USA) into the distal right cervical ICA.

Expanding the stroke team to include interventional cardiology.

Team-based care has been emphasized as a strategy to improve and optimize outcomes for broad groups of patients who have presented with often complex medical conditions including large vessel cerebral occlusion. Although neurointerventionalists from different specialties perform mechanical embolectomy, which has become the standard of care for large vessel cerebral occlusion, these specialties are limited by relatively low numbers typically concentrated in a small number of sites. In this single center experience, approximately 50 patients with large vessel stroke were transferred out of an emergency room to other centers despite the availability of an experienced cardiologist with extensive carotid experience.

Classification models using circulating neutrophil transcripts can detect unruptured intracranial aneurysm.

Background: Intracranial aneurysms (IAs) are dangerous because of their potential to rupture. We previously found significant RNA expression differences in circulating neutrophils between patients with and without unruptured IAs and trained machine learning models to predict presence of IA using 40 neutrophil transcriptomes. Here, we aim to develop a predictive model for unruptured IA using neutrophil transcriptomes from a larger population and more robust machine learning methods.