MRI in patients with a cerebral aneurysm clip; review of the literature and incident databases and recommendations for the Netherlands.

Background: In the past ferromagnetic cerebral aneurysm clips that are contraindicated for Magnetic Resonance Imaging (MRI) have been implanted. However, the specific clip model is often unknown for older clips, which poses a problem for individual patient management in clinical care.

Methods: Literature and incident databases were searched, and a survey was performed in the Netherlands that identified time periods at which ferromagnetic and non-ferromagnetic clip models were implanted.

Anesthesia Depresses Cerebrovascular Reactivity to Acetazolamide in Pediatric Moyamoya Vasculopathy.

Measurements of cerebrovascular reactivity (CVR) are essential for treatment decisions in moyamoya vasculopathy (MMV). Since MMV patients are often young or cognitively impaired, anesthesia is commonly used to limit motion artifacts. Our aim was to investigate the effect of anesthesia on the CVR in pediatric MMV.

Clinical Outcome, Cognition, and Cerebrovascular Reactivity after Surgical Treatment for Moyamoya Vasculopathy: A Dutch Prospective, Single-Center Cohort Study.

Background: It remains unclear whether revascularization of moyamoya vasculopathy (MMV) has a positive effect on cognitive function. In this prospective, single-center study, we investigated the effect of revascularization on cognitive function in patients with MMV. We report clinical and radiological outcome parameters and the associations between clinical determinants and change in neurocognitive functioning.

Development of the SAFETEA Scores for Predicting Risks of Complications of Preventive Endovascular or Microneurosurgical Intracranial Aneurysm Occlusion.

Background And Objectives: Preventive unruptured intracranial aneurysm (UIA) occlusion can reduce the risk of subarachnoid hemorrhage, but both endovascular and microneurosurgical treatment carry a risk of serious complications. To improve individualized management decisions, we developed risk scores for complications of endovascular and microneurosurgical treatment based on easily retrievable patient, aneurysm, and treatment characteristics.

Methods: For this multicenter cohort study, we combined individual patient data from patients with UIA aged 18 years or older undergoing preventive endovascular treatment (standard, balloon-assisted or stent-assisted coiling, Woven EndoBridge-device, or flow-diverting stent) or microneurosurgical clipping at one of the 10 participating centers from 3 continents between 2000 and 2018.

Quality of Life Outcomes Over Time in Patients With Unruptured Intracranial Aneurysms With and Without Preventive Occlusion: A Prospective Cohort Study.

Background And Objectives: In counseling patients with an unruptured intracranial aneurysm (UIA), quality of life (QoL) outcomes are important for informed decision making. We evaluated QoL outcomes in patients with and without preventive aneurysm occlusion at multiple time points during the first year after UIA diagnosis and studied predictors of QoL outcomes.

Methods: We performed a prospective cohort study in patients aged ≥18 years with a newly diagnosed UIA in 2 tertiary referral centers in the Netherlands between 2017 and 2019.

The Sutureless Excimer Laser Anastomosis Clip Pilot Study: a feasibility and safety study.

Background: The excimer laser-assisted non-occlusive anastomosis (ELANA) bypass technique may have the advantage of its non-occlusive design in the treatment of last-resort cases where endovascular treatment or direct clipping is considered to be unsafe. However, the technique remains technically challenging. Therefore, a sutureless ELANA Clip device (SEcl) was developed to simplify the technique avoiding tedious anastomosis stitching in depth.

The profile of cognitive impairment and hemodynamic compromise in moyamoya: a single-center prospective cohort study.

Objective: Patients with moyamoya vasculopathy often experience cognitive impairments. In this prospective single-center study, the authors investigated the profile of neurocognitive impairment and its relation with the severity of ischemic brain lesions and hemodynamic compromise.

Methods: Patients treated in a Dutch tertiary referral center were prospectively included.

Safety and biodegradability of a synthetic dural sealant patch (Liqoseal) in a porcine cranial model.

Background: Liqoseal consists of a watertight layer of poly(ester)ether urethane and an adhesive layer containing polyethylene glycol--hydroxysuccinimide (PEG-NHS). It is designed to prevent cerebrospinal fluid (CSF) leakage after intradural surgery. This study assessed the safety and biodegradability of Liqoseal in a porcine craniotomy model.

Contralateral improvement of cerebrovascular reactivity and TIA frequency after unilateral revascularization surgery in moyamoya vasculopathy.

Objective: Moyamoya vasculopathy is a rare, often bilateral disease characterized by progressive stenosis and occlusion of the distal internal carotid artery, leading to a progressive deterioration of cerebrovascular reactivity (CVR) and increased risk of transient ischemic attacks (TIAs), infarction and hemorrhage. Surgical revascularization is a widely accepted symptomatic treatment, often performed bilaterally in one or two stages. To possibly further optimize treatment strategy, we investigated the effect of unilateral revascularization surgery on the CVR of, and TIA frequency originating from, the contralateral hemisphere.

Minimizing complications in a porcine survival craniotomy model.

A large craniotomy survival porcine model is useful for scientific research. The surgical approaches and complications of craniotomies in pigs have not been published before. This study describes how large craniotomies were performed in 46 pigs and how the risk of complications was minimized.

Patients with Moyamoya Vasculopathy Evaluated at a Single-Center in The Netherlands; Clinical Presentation and Outcome.

Information on presentation and outcome of moyamoya vasculopathy (MMV) in European countries is limited. We investigated patient characteristics, treatment and outcome of patients with MMV. We retrieved patient characteristics and treatment information and determined functional outcome (modified Rankin Score (mRS); type of school/work) by structured telephone interviews.

Effects of dobutamine and phenylephrine on cerebral perfusion in patients undergoing cerebral bypass surgery: a randomised crossover trial.

Background: Patients undergoing cerebral bypass surgery are prone to cerebral hypoperfusion. Currently, arterial blood pressure is often increased with vasopressors to prevent cerebral ischaemia. However, this might cause vasoconstriction of the graft and cerebral vasculature and decrease perfusion.

Histologic Comparison of the Dura Mater among Species.

The biocompatibility, biodegradation, feasibility, and efficacy of medical devices like dural sealants and substitutes are often evaluated in various animal models. However, none of these studies explain the rationale for choosing a particular species, and a systematic interspecies comparison of the dura is not available. We hypothesized that histologic characteristics of the dura would differ among species.

Preventable poor outcome from rebleeding by emergency aneurysm occlusion in patients with aneurysmal subarachnoid haemorrhage.

Introduction: The risk of rebleeding is highest during the initial hours after aneurysmal subarachnoid haemorrhage (aSAH), but the aneurysm is not occluded in all patients immediately after admission.Our aim was to determine the proportion of aSAH patients with poor outcome from early in-hospital rebleeding that can be prevented by three emergency aneurysm occlusion regimes.

Patients And Methods: From our prospectively collected database, we retrieved from all aSAH patients admitted between July 2007 and July 2017 data on clinical condition on admission, time of rebleeding, and outcome at 3 months.

RNA-Sequencing Highlights Inflammation and Impaired Integrity of the Vascular Wall in Brain Arteriovenous Malformations.

Background and Purpose- Interventional treatment of unruptured brain arteriovenous malformations (BAVMs) has become increasingly controversial. Because medical therapy is still lacking, we aimed to obtain insight into the disease mechanisms implicated in BAVMs and to identify potential targets for medical treatment to prevent rupture of a BAVM. Methods- We used next-generation RNA sequencing to identify differential expression on a transcriptome-wide level comparing tissue samples of 12 BAVMs to 16 intracranial control arteries.

Final Results of the Prospective Multicenter Excimer Laser-Assisted High-Flow Bypass Study on the Treatment of Giant Anterior Circulation Aneurysms.

Background: Both conventional bypass utilizing temporary recipient vessel occlusion and the excimer laser-assisted nonocclusive anastomosis (ELANA) bypass technique are possible strategies in the treatment of giant aneurysms. These treatments have only been studied in single institutional retrospective studies. The potential advantage of the ELANA technique is the absence of temporary occlusion of major arteries, decreasing the risk of intraoperative ischemia.

A patient-specific cerebral blood flow model.

In clinical practice, many complex choices in treatment of complex cerebrovascular diseases have to be made. A patient-specific mathematical blood flow could aid these decisions. For certain cases, less accuracy is required and more simplistic models might be feasible.

Aneurysm characteristics and risk of rebleeding after subarachnoid haemorrhage.

Introduction: Knowledge of risk factors for rebleeding after aneurysmal subarachnoid haemorrhage can help tailoring ultra-early aneurysm treatment. Previous studies have identified aneurysm size and various patient-related risk factors for early (≤24 h) rebleeding, but it remains unknown if aneurysm configuration is also a risk factor. We investigated whether irregular shape, aspect- and bottleneck ratio of the aneurysm are independent risk factors for early rebleeding after aneurysmal subarachnoid haemorrhage.

Effectiveness of Sealants in Prevention of Cerebrospinal Fluid Leakage after Spine Surgery: A Systematic Review.

Background: Sealants are often used in spine surgery to prevent postoperative cerebrospinal fluid (CSF) leakage.

Objective: To investigate the efficacy of sealants in preventing postoperative CSF leakage in spine surgery.

Methods: The PubMed, Embase, and Cochrane databases were searched for articles reporting the outcome of patients treated with a sealant for spinal dural repair.

Cerebrovascular Reactivity Measured with ASL Perfusion MRI, Ivy Sign, and Regional Tissue Vascularization in Moyamoya.

Background: Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) may be used to determine brain regions at risk for ischemia in patients with moyamoya vasculopathy and to identify patients who may benefit from surgical revascularization. We aimed to investigate whether 1) the severity of moyamoya is related to the presence of leptomeningeal collaterals and cerebrovascular reactivity (CVR), 2) the presence of collaterals and ivy sign reflects disturbed CVR, and 3) arterial transit artefacts (ATAs) and ivy sign reflect the presence of collaterals.

Methods: We determined severity of moyamoya on digital subtraction angiography (DSA) according to the modified Suzuki classification in 20 brain regions and scored regional tissue revascularization using a 4-point scale.

Branching Pattern of the Cerebral Arterial Tree.

Quantitative data on branching patterns of the human cerebral arterial tree are lacking in the 1.0-0.1 mm radius range.

Cognitive Functions in Children and Adults with Moyamoya Vasculopathy: A Systematic Review and Meta-Analysis.

Background And Purpose: Patients with moyamoya vasculopathy (MMV) may experience cognitive impairment, but its reported frequency, severity, and nature vary. In a systematic review and metaanalysis, we aimed to assess the presence, severity, and nature of cognitive impairments in children and adults with MMV.

Methods: We followed the MOOSE guidelines for meta-analysis and systematic reviews of observational studies.

High resolution 7T and 9.4T-MRI of human cerebral arterial casts enables accurate estimations of the cerebrovascular morphometry.

Quantitative data on the morphology of the cerebral arterial tree could aid in modelling and understanding cerebrovascular diseases, but is scarce in the range between 200 micrometres and 1 mm diameter arteries. Traditional manual measurements are difficult and time consuming. 7T-MRI and 9.

Functional and educational outcomes after treatment for intracranial arteriovenous malformations in children.

Background: Arteriovenous malformations (AVMs) in the pediatric population are rare, yet they form the most frequent cause of hemorrhagic stroke in children. Compared to adults, children have been suggested to have beneficial neurological outcomes. However, few studies have focused on other variables than neurological outcomes.