Tenzingplasty for cerebral vasospasm following subarachnoid hemorrhage or meningitis: multicenter initial experience.

Background: Cerebral vasospasm is a serious complication of intracranial pathologies. Treatment involves intensive medical therapy that may require augmentation with endovascular therapy, most commonly intra-arterial calcium channel blocker infusion. Angioplasty is historically reserved for refractory cases at risk for infarct.

Multicenter experience of the Monopoint reperfusion system in acute large vessel occlusion stroke thrombectomy.

Background: The Monopoint reperfusion system (Monopoint; Route 92 Medical, San Mateo, California, USA) is a large bore (0.088 or 0.070 inch inner diameter) aspiration thrombectomy platform designed to minimize ledge effect and improve neurovascular navigation and embolectomy.

Intracranial Dotter angioplasty using Tenzing (Tenzingplasty) for acute ischemic stroke with underlying intracranial atherosclerotic disease.

Introduction: Catheter-mediated (Dotter) angioplasty has been previously described for extracranial/peripheral arteries. Tenzing (Route 92 Medical, San Mateo, California, USA), a shelf-reducing delivery catheter, has an atraumatic tapered distal tip that progressively enlarges to maximal outer diameter of 1.2 mm (Tenzing 5), 1.

Tenzing Assisted Delivery of Aspiration (TADA) technique for thrombectomy of medium vessel occlusions using the Freeclimb 54 catheter: multicenter experience.

Background: Medium vessel occlusions (MeVOs) account for 25-40% of acute ischemic stroke. The Tenzing 5 (Route 92 Medical, San Mateo, California, USA) and FreeClimb 54 (Route 92 Medical, San Mateo, California, USA) catheter is a novel delivery-aspiration catheter combination designed to facilitate aspiration thrombectomy (AT) of MeVOs. We report our clinical experience using the Tenzing assisted delivery of aspiration (TADA) technique with FreeClimb 54 for first-line AT of MeVO.

Imaging in acute ischaemic stroke: assessing findings in light of evolving therapies.

Acute ischaemic stroke (AIS) is a debilitating disease for which effective therapies are now available. Effective identification of candidates for therapy relies heavily on noninvasive imaging that must be interpreted accurately in a short timeframe. This review summarizes the evolution of AIS therapies and the implications for noninvasive imaging.

Analysis of treatment cost differences in patients undergoing femoral versus radial access in outpatient diagnostic cerebral arteriograms.

Background: Outpatient diagnostic cerebral arteriograms are the most common procedure in neuroendovascular surgery, and the use of transradial access for these studies is growing. Although transradial access has been associated with lower hospital costs for elective diagnostic and interventional neuroendovascular procedures, no study has compared transfemoral access and transradial access costs for a homogenous population of patients undergoing outpatient diagnostic cerebral arteriogram.

Methods: In this single-center retrospective study, the Value Driven Outcomes database was used to evaluate treatment costs for patients who underwent outpatient diagnostic cerebral arteriogram from January 2019 to December 2022.

Hemorrhagic Safety of Magnetic Resonance-Guided Focused Ultrasound Thalamotomy for Tremor without Interruption of Antiplatelet or Anticoagulant Therapy.

Introduction: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is an incision-less ablative technique used to treat medically refractory tremor. Although intracerebral hemorrhage has not been reported with MRgFUS thalamotomy for the treatment of movement disorders, clinicians commonly interrupt active blood thinning medications prior to the procedure or offer gamma knife radiosurgery instead. However, MRgFUS uses focal thermoablation, and bleeding risk is likely minimal.

Evaluation of methemoglobin as an intravascular contrast agent: T1 relaxation time effect in a rabbit model.

Objective: Alternative contrast agents for MRI are needed for individuals who may respond adversely to gadolinium, and need an intravascular agent for specific indications. One potential contrast agent is intracellular methemoglobin, a paramagnetic molecule that is normally present in small amounts in red blood cells. An animal model was used to determine whether methemoglobin modulation with intravenous sodium nitrite transiently changes the T1 relaxation of blood.

Influence of cerebrospinal fluid on power absorption during transcranial magnetic resonance-guided focused ultrasound treatment.

Background: Ultrasound beam aberration correction is vital when focusing ultrasound through the skull bone in transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) applications. Current methods make transducer element phase adjustments to compensate for the variation in skull properties (shape, thickness, and acoustic properties), but do not account for variations in the internal brain anatomy.

Purpose: Our objective is to investigate the effect of cerebrospinal fluid (CSF) and brain anatomy on beam focusing in tcMRgFUS treatments.

Real-Time Monitoring and Modulation of Blood Pressure in a Rabbit Model of Ischemic Stroke.

Control of blood pressure, in terms of both absolute values and its variability, affects outcomes in ischemic stroke patients. However, it remains challenging to identify the mechanisms that lead to poor outcomes or evaluate measures by which these effects can be mitigated because of the prohibitive limitations inherent to human data. In such cases, animal models can be utilized to conduct rigorous and reproducible evaluations of diseases.

Association between high-risk extracranial carotid plaque and covert brain infarctions and cerebral microbleeds.

Purpose: Covert brain infarctions (CBIs) and cerebral microbleeds (CMBs) represent subclinical sequelae of ischemic and hemorrhagic cerebral small vessel disease, respectively. In addition to thromboembolic stroke, carotid atherosclerosis has been associated with downstream vascular brain injury, including inflammation and small vessel disease. The specific plaque features responsible for this are unknown.

Discovery of CC-99677, a selective targeted covalent MAPKAPK2 (MK2) inhibitor for autoimmune disorders.

As an anti-inflammatory strategy, MAPK-activated protein kinase-2 (MK2) inhibition can potentially avoid the clinical failures seen for direct p38 inhibitors, especially tachyphylaxis. CC-99677, a selective targeted covalent MK2 inhibitor, employs a rare chloropyrimidine that bonds to the sulfur of cysteine 140 in the ATP binding site via a nucleophilic aromatic substitutions (SAr) mechanism. This irreversible mechanism translates biochemical potency to cells shown by potent inhibition of heat shock protein 27 (HSP27) phosphorylation in LPS-activated monocytic THP-1 cells.

Idiopathic intracranial hypertension imaging approaches and the implications in patient management.

Idiopathic intracranial hypertension (IIH) represents a clinical disease entity without a clear etiology, that if left untreated, can result in severe outcomes, including permanent vision loss. For this reason, early diagnosis and treatment is necessary. Historically, the role of cross-sectional imaging has been to rule out secondary or emergent causes of increased intracranial pressure, including tumor, infection, hydrocephalus, or venous thrombosis.

Endovascular mechanical thrombectomy in a child with COVID-19: Clot analysis reveals a novel pathway in the neuroinflammatory cascade resulting in large-vessel occlusion.

Large-vessel occlusion is rare in children, but its results can be devastating and may lead to recurrent strokes, persistent neurological deficits, and decreased quality of life. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has yielded extrapulmonary effects and multiorgan diseases, many of which are neurological manifestations. There is a paucity of literature in pediatric patients about large-vessel occlusion in the setting of COVID-19 infection.

Neutrophil extracellular traps regulate ischemic stroke brain injury.

Ischemic stroke prompts a strong inflammatory response, which is associated with exacerbated outcomes. In this study, we investigated mechanistic regulators of neutrophil extracellular trap (NET) formation in stroke and whether they contribute to stroke outcomes. NET-forming neutrophils were found throughout brain tissue of ischemic stroke patients, and elevated plasma NET biomarkers correlated with worse stroke outcomes.

Spatially resolved transcriptomics for evaluation of intracranial vessels in a rabbit model: Proof of concept.

Background: Better understanding of vessel biology and vascular pathophysiology is needed to improve understanding of cerebrovascular disorders. Tissue from diseased vessels can offer the best data. Rabbit models can be effective for studying intracranial vessels, filling gaps resulting from difficulties acquiring human tissue.

Balance and cognitive impairments are prevalent and correlated with age in presurgical patients with essential tremor.

Introduction: Essential tremor (ET) was long considered a monosymptomatic disorder, but this view has given way to a more comprehensive clinical picture that involves consideration of non-tremor symptoms (e.g., balance impairment, cognitive impairment).

MR Angiography Series: Neurovascular MR Angiography.

Neurovascular MR angiography (MRA) is an evolving imaging technique and is crucial for the workup of numerous neurologic disorders. While CT angiography (CTA) provides a more rapid imaging assessment, in select patients it can impart a small risk of contrast material-induced nephrotoxicity or radiation-associated cancers. In addition, MRA offers some advantages over CTA for neurovascular evaluation, including higher temporal resolution and the capability for vessel wall imaging.

MR Perfusion in the Evaluation of Mechanical Thrombectomy Candidacy.

Stroke is a leading cause of disability and mortality, and the incidence of ischemic stroke is projected to continue to rise in coming decades. These projections emphasize the need for improved imaging techniques for accurate diagnosis allowing effective treatments for ischemic stroke. Ischemic stroke is commonly evaluated with computed tomography (CT) or magnetic resonance imaging (MRI).

Postmarket American Experience With Woven EndoBridge Device: Adjudicated Multicenter Case Series.

Background: The Woven EndoBridge (WEB) device was granted premarket approval in the United States following results of the Woven EndoBridge Intrasaccular Therapy (WEB-IT) study. WEB-IT reported excellent adequate angiographic occlusion of treated aneurysms with a high safety profile. These results were achieved, however, in the context of a prospective study with strict inclusion criteria and rigorous training support.

Duration of symptomatic stroke and successful reperfusion with endovascular thrombectomy for anterior circulation large vessel occlusive stroke.

Background: It has been reported that longer time intervals from stroke onset to endovascular therapy are associated with lower rates of successful reperfusion in acute ischemic stroke patients with large vessel occlusion. However, procedural variables and potential mechanisms of this association have not been fully elucidated.

Methods: We performed a secondary analysis of individual patient data from the North American Solitaire Stent Retriever Acute Stroke (NASA) and Trevo Stent-Retriever Acute Stroke (TRACK) registries.

Rabbit models of intracranial atherosclerotic disease for pathological validation of vessel wall MRI.

Introduction: Vessel wall magnetic resonance imaging can improve the evaluation of intracranial atherosclerotic disease. However, pathological validation is needed to improve vessel wall magnetic resonance imaging techniques. Human pathology samples are not practical for such analysis, so an animal model is therefore needed.

"And do no harm": Complications in interventional neuroradiology.

Complications are an unfortunate reality in the field of interventional neuroradiology. While complications cannot be eliminated entirely, their occurrence and severity can be mitigated by the competency achieved through training, knowledge of cerebrovascular anatomy and pathology, and well-conceived and executed plans crafted in conjunction with a multidisciplinary team. Frequent communication among the team throughout the entire process of care is vital.

Neurovascular venous anatomy: Brain, head, and neck.

The venous anatomy of the brain, head, and neck is essential to endovascular diagnosis and therapy. This chapter provides an overview of the venous system.