Natural history of dolichoectatic vertebrobasilar aneurysms: a multinational study.

Objective: Dolichoectatic vertebrobasilar aneurysms (DVBAs) are expansions of arterial tissue leading to aneurysmal formations without an obvious neck. Their natural history is poorly understood; usually patients are admitted with thromboembolic complications and/or neurological symptoms from the mass effect. There have not been international collective data, and correct timing for highly risky treatments has been under discussion.

Retrosigmoid Craniectomy for Clip Ligation of Flow-Diverted Posterior Inferior Cerebellar Artery Aneurysm.

Flow diversion (FD) has revolutionized the treatment of cerebral aneurysms. Since the introduction of the Pipeline Embolization Device, there has been a significant shift in the management of cerebral aneurysms, with increasing emphasis being placed on use of endoluminal reconstruction as a means of long-term, durable treatment of aneurysms. Increasingly, FD stents are being used as primary treatment for aneurysms, including those that present with subarachnoid hemorrhage.

Exploring the dynamics of adult cell lineage integration into dentate gyrus granule neurons.

The Wnt pathway plays critical roles in neurogenesis. The expression of is induced by Wnt/β-catenin signaling, making this gene a reliable indicator of canonical Wnt activity. We employed pulse-chase genetic lineage tracing with the allele to follow the fate of + lineage in the adult hippocampal formation.

Keyhole Retrosigmoid Craniotomy for Lateral Pontine Cavernous Malformation.

With improvements in anesthesia, monitoring, and peroperative care, the surgical removal of intrinsic brainstem pathology has become a possibility. Although surgical removal of deep-seated lesions continues to have significant morbidity, at least temporarily, associated with it, removal of exophytic lesions can be accomplished with little disability for the patient. The key to a good outcome, when removing cerebral cavernous malformation, is preservation of adjacent neurovascular bundles, use of sharp dissection over blunt pulling, judicious use of cautery in and around the brainstem, and preservation of the developmental venous anomaly, when present.

Transcervical Vertebral Artery Origin Endarterectomy for Vertebrobasilar Insufficiency.

Vertebral artery (VA) stenosis is a cause of vertebrobasilar insufficiency (VBI) and disabling posterior circulation stroke, accounting for up to 30% of all strokes. Although the natural history of VBI is not as well delineated as that of carotid stenosis, strokes in the basilar circulation can be more disabling than their anterior circulation counterparts. Stenosis exceeding 30% at the origin of the vertebral artery is associated with increased risk of stroke.

Contralateral Interhemispheric Transfalcine Approach to the Basal Ganglia.

The contralateral interhemispheric approach provides a robust path into the mesial frontal lobe and basal ganglia structures. The use of gravity to retract the dominant frontal lobe allows the surgeon to avoid injury caused by exposure of the dominant hemisphere. The transfalcine corridor, however, is long and often not well illuminated, necessitating the use of lighted instruments.

Dynamics of Adult Cell Lineage Integration in Granule Neurons of the Dentate Gyrus.

The Wnt pathway plays critical roles in neurogenesis. The expression of is induced by Wnt/β-catenin signaling, making this gene a sensitive indicator of canonical Wnt activity. We employed pulse-chase genetic lineage tracing with the allele to follow the fate of -positive cells in the adult hippocampal formation.

Recurrence of a large intracranial fusiform aneurysm treated with overlapping Pipeline embolization devices: illustrative case.

Background: Flow diversion, specifically with the Pipeline embolization device (PED), represents a paradigm shift in the treatment of intracranial aneurysms. Several studies have demonstrated its efficacy and at times superiority to conventional treatment modalities for aneurysms with a fusiform morphology, giant size, or wide neck. However, there may be a nonsignificant risk of recurrence after flow diversion of these historically difficult-to-treat aneurysms, relative to aneurysms with a more favorable morphology and size (i.

Intraarterial Transplantation of Mitochondria After Ischemic Stroke Reduces Cerebral Infarction.

Background-: Transplantation of autologous mitochondria into ischemic tissue may mitigate injury caused by ischemia and reperfusion.

Methods-: Using murine stroke models of middle cerebral artery occlusion, we sought to evaluate feasibility of delivery of viable mitochondria to ischemic brain parenchyma. We evaluated the effects of concurrent focused ultrasound activation of microbubbles, which serves to open the blood-brain barrier, on efficacy of delivery of mitochondria.

Preclinical models of middle cerebral artery occlusion: new imaging approaches to a classic technique.

Stroke remains a major burden on patients, families, and healthcare professionals, despite major advances in prevention, acute treatment, and rehabilitation. Preclinical basic research can help to better define mechanisms contributing to stroke pathology, and identify therapeutic interventions that can decrease ischemic injury and improve outcomes. Animal models play an essential role in this process, and mouse models are particularly well-suited due to their genetic accessibility and relatively low cost.

Magnetic Resonance Imaging of Mouse Cerebral Cavernomas Reveal Differential Lesion Progression and Variable Permeability to Gadolinium.

Background: Cerebral cavernous malformations, also known as cavernous angiomas, are blood vessel abnormalities comprised of clusters of grossly enlarged and hemorrhage-prone capillaries. The prevalence in the general population, including asymptomatic cases, is estimated to be 0.5%.

Reperfusion injury in acute ischemic stroke: Tackling the irony of revascularization.

Reperfusion injury is an unfortunate consequence of restoring blood flow to tissue after a period of ischemia. This phenomenon can occur in any organ, although it has been best studied in cardiac cells. Based on cardiovascular studies, neuroprotective strategies have been developed.

Minimally Invasive, Supine, Lateral Supracerebellar Infratentorial Approach for Resection of a Pineal Cyst.

Most pineal cysts are not surgical lesions and should be conservatively managed. Select lesions, notably those that present with hydrocephalus and Parinaud syndrome and lesions presenting with symptoms consistent with intermittent blockage of cerebrospinal fluid pathways and/or neurovascular compression, however, can be considered for surgical intervention. Two workhorse surgical approaches to the pineal region include the occipital interhemispheric transtentorial and supracerebellar infratentorial approaches.

Modified Orbitozygomatic Craniotomy for Clipping of a Ruptured Thrombotic A1-A2 Aneurysm.

Ruptured thrombotic aneurysms pose a dual challenge of subarachnoid hemorrhage and local mass effect on neurovascular structures causing cranial nerve palsies or other neurologic symptoms. Although many thrombotic aneurysms can be treated with endovascular techniques, the benefit of surgical treatment of these aneurysms is the fact that clipping can be followed by removal of the clot and decompression of the contents of the aneurysm sac, thereby relieving local mass effect. In Video 1 we present the case of a young man with a ruptured thrombotic anterior cerebral artery (first segment of anterior cerebral artery-second segment of anterior cerebral artery) aneurysm who presented with bilateral vision loss.

A Novel Tissue Atlas and Online Tool for the Interrogation of Small RNA Expression in Human Tissues and Biofluids.

One promising goal for utilizing the molecular information circulating in biofluids is the discovery of clinically useful biomarkers. Extracellular RNAs (exRNAs) are one of the most diverse classes of molecular cargo, easily assayed by sequencing and with expressions that rapidly change in response to subject status. Despite diverse exRNA cargo, most evaluations from biofluids have focused on small RNA sequencing and analysis, specifically on microRNAs (miRNAs).

Biomarkers Predictive of Long-Term Outcome After Ischemic Stroke: A Meta-Analysis.

Background And Objective: The goal of this study was to systematically review the usefulness of serum biomarkers in the setting of ischemic stroke (IS) to predict long-term outcome.

Methods: A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2018. All studies assessing long-term functional outcome (defined as ≥30 days) after IS with respect to serum biomarkers were included.

A subset of arachnoid granulations in humans drain to the venous circulation via intradural lymphatic vascular channels.

Objective: The discovery of dural lymphatics has spurred interest in the mechanisms of drainage of interstitial fluid from the CNS, the anatomical components involved in clearance of macromolecules from the brain, mechanisms of entry and exit of immune components, and how these pathways may be involved in neurodegenerative diseases and cancer metastasis. In this study the authors describe connections between a subset of arachnoid granulations (AGs) and the venous circulation via intradural vascular channels (IVCs), which stain positively with established lymphatic markers. The authors postulate that the AGs may serve as a component of the human brain's lymphatic system.

How to Perform Intra-Operative Contrast-Enhanced Ultrasound of the Brain-A WFUMB Position Paper.

Intra-operative ultrasound has become a relevant imaging modality in neurosurgical procedures. While B-mode, with its intrinsic limitations, is still considered the primary ultrasound modality, intra-operative contrast-enhanced ultrasound (ioCEUS) has more recently emerged as a powerful tool in neurosurgery. Though still not used on a large scale, ioCEUS has proven its utility in defining tumor boundaries, identifying lesion vascular supply and mapping neurovascular architecture.

Anatomical Features of the Deep Cervical Lymphatic System and Intrajugular Lymphatic Vessels in Humans.

Background: Studies in rodents have re-kindled interest in the study of lymphatics in the central nervous system. Animal studies have demonstrated that there is a connection between the subarachnoid space and deep cervical lymph nodes (DCLNs) through dural lymphatic vessels located in the skull base and the parasagittal area.

Objective: To describe the connection of the DCLNs and lymphatic tributaries with the intracranial space through the jugular foramen, and to address the anatomical features and variations of the DCLNs and associated lymphatic channels in the neck.

Mitochondrial dysfunction in neurological disorders: Exploring mitochondrial transplantation.

Mitochondria are fundamental for metabolic homeostasis in all multicellular eukaryotes. In the nervous system, mitochondria-generated adenosine triphosphate (ATP) is required to establish appropriate electrochemical gradients and reliable synaptic transmission. Notably, several mitochondrial defects have been identified in central nervous system disorders.

Systematic Review of Functional Mapping and Cortical Reorganization in the Setting of Arteriovenous Malformations, Redefining Anatomical Eloquence.

The goal of this study was to systematically review functional mapping and reorganization that takes place in the setting of arteriovenous malformations (AVMs) and its potential impact on grading and surgical decision making. A systematic literature review was performed using the PubMed database for studies published between 1986 and 2019. Studies assessing brain mapping and functional reorganization in AVMs were included.