Abstract Background and aims Early prognostication after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) is crucial for guiding clinical management. Transcranial sonography–derived midline shift (MLS) may serve as a noninvasive biomarker for outcome prediction. We aimed to assess whether early dynamics in sonography–derived MLS were associated with clinical and radiologic signs of cerebral injury following EVT. Methods In this prospective single-center study of patients with anterior-circulation AIS treated with EVT, sonography-derived MLS was assessed at <3, 6-24, and 24-48h after recanalization. Outcomes included MRI-based infarct volume, Heidelberg Bleeding Classification (HBC), and 24-hour National Institutes of Health Stroke Scale (NIHSS). MLS at serial time points and MLS progression (increase from first to last exam) were correlated with infarct volume (square-root–transformed) using Pearson’s correlation. MLS was compared between patients stratified by presence of intracranial hemorrhage and early neurological recovery (NIHSS ≤8) using Student’s t-tests. Results Fifty-five patients were included (median age 69 years; 31% female). MLS at 6-24h (r=0.39, p=0.020), 24-48h (r=0.68, p=0.002) and MLS progression (r=0.49, p=0.034) correlated with infarct volume. Patients with early neurological recovery had smaller MLS at 6-24h (0.1 vs 1.3mm, p=0.003) and 24-48h (0.1 vs 2.1mm, p=0.008) and lower MLS progression (0.1 vs 1.1mm, p=0.020) than others. Patients with parenchymal hematomas (HBC ≥PH1) had greater MLS at <3h (0.7 vs -0.1mm p= 0.045) than those without. Conclusions Transcranial sonographic monitoring after EVT provides noninvasive estimates of MLS that may represent early markers of cerebral injury. Larger studies are needed to validate its clinical utility. Conflict of interest Lars Tveit: nothing to disclose

Abstract Background and aims Brain-derived tau (BD-tau) is a sensitive blood-based biomarker of neuronal injury in acute ischemic stroke; but its relevance in conditions characterized by chronic cerebral hypoperfusion remains unclear. Moyamoya angiopathy (MMA) is a progressive steno-occlusive disorder causing regional cerebral hypoperfusion, impaired vasomotor reserve, and heterogenous clinical phenotypes, including cognitive impairment, complicating risk stratification. Biomarkers reflecting hypoperfusion-related neuronal injury may complement imaging and clinical assessment in neurosurgical decision- making. We investigated serum BD-tau levels in MMA patients and healthy controls and explored relations with cognitive performance. Methods This cross-sectional, register-based case-control study included MMA patients without recent stroke (n = 37) and healthy controls (n = 14). Serum total BD-tau levels were compared using Mann-Whitney U test. MMA patients underwent comprehensive neuropsychological assessment across nine cognitive domains. A Global Cognitive Impairment Index (GCII) was calculated as the proportion of domains with at least one test score ≥1 standard deviation below normative means. Associations between BD-tau and GCII were assessed using Spearman´s rank correlation. Results Median serum BD-tau levels were 12.38 [9.40–14.96] pg/mL in the MMA group and 9.97 [9.27–13.77] pg/mL in the control group, without significant between-group difference (p = 0.263). Within the MMA group, BD-tau levels showed no significant correlation with GCII (p = 0.061). Conclusions Serum BD-tau levels were not elevated in MMA patients and were not associated with global impairment. Despite small sample size, these findings suggest limited general utility of BD-tau in MMA, though its potential in selected subgroups warrants further investigation in larger cohorts. Conflict of interest Jesper Sømark: nothing to disclose. Mona Skjelland: non-personal research grants from South-Eastern Norway Regional Health Authority (2024). Bente Halvorsen: is an SAB member in CircM, Linkøping, Sweden and is an evaluator in MH panel, Swedish Research council.. Thor Ueland: nothing to disclose.Vigdis Bjerkeli: nothing to disclose. Pål Aukrust: nothing to disclose. Tonje Nordenmark: nothing to disclose. Markus K.H. Wiedmann: nothing to disclose. Anne Hege Aamodt: has received personal fees for lectures/advisory boards; Novartis, Abbvis, TEVA, Roche, Lundbeck, Pfizer, Boehringer Ingelheim, non-personal research grants from Norwegian National Association for Public Health, South-Eastern Norway regional Health Authority, Odd Fellow, National Program for Clinical Treatment Research in the Specialist Health Service (KLINBEFORSK), EU, Boehringer Ingelheim, Medtronic, BMS. Figure 1 - belongs to Conclusions

IntroductionCerebral autoregulation (CA) is essential for protecting the brain against harmful fluctuations in cerebral blood flow (CBF) and may be severely impaired in acute ischemic stroke (AIS) patients. Continuous wavelet transform (CWT) is a robust method for quantifying CA. However, data on CWT-based metrics following endovascular thrombectomy (EVT) remain limited. Therefore, we aimed to characterize CA using CWT in AIS patients after EVT.MethodsWe performed a prospective observational study recruiting patients with anterior circulation AIS treated with EVT. Continuous bilateral middle cerebral artery (MCA) blood flow velocities were obtained by transcranial doppler ultrasound (TCD) and synchronized with arterial blood pressure (ABP). CWT-derived Synchronization index gamma (SI) was calculated in the very-low frequency range (0.005–0.08 Hz). The primary outcome was an unfavorable clinical outcome at 90-days (modified Rankin Scale 3–6). Secondary outcomes were early neurological recovery, Alberta Stroke Program Early CT Score (ASPECTS), MRI-based infarct volume, and intracranial hemorrhage.ResultsA total of 20 patients were included in the primary outcome analysis. There was no statistically significant difference in median Synchronization index gamma (SI) between patients with unfavorable clinical outcomes compared to patients with favorable clinical outcomes (0.61 ±0.15 vs. 0.41 ±0.20, p = 0.055). Patients who failed to achieve early neurological recovery had higher median SI compared to others (0.63 ±0.14 vs. 0.36 ±0.17, p = 0.005). Median SI was inversely correlated with ASPECTS, indicating impaired CA in larger infarcts (Spearman's rho = −0.52, p = 0.043).ConclusionCWT is a viable method for evaluating CA after EVT and may provide important information on early cerebral hemodynamics following arterial recanalization.

BACKGROUND:Moyamoya angiopathy (MMA) is a rare, progressive cerebrovascular disorder characterized by stenosis or occlusion of the terminal internal carotid arteries, leading to the development of fragile collateral vessels. Headache is a common but understudied symptom of MMA, reported in up to 75% of patients. The headache phenotype often mimics migraine or tension-type headache, although cluster headache-like episodes have also been described. Aims to summarize current evidence on the clinical characteristics, underlying mechanisms, and treatment strategies for headache in MMA. MATERIALS AND METHODS:A narrative review of the literature was conducted, focusing on the prevalence, phenotype, pathophysiological mechanisms, and therapeutic options for headache in MMA. RESULTS:The pathogenesis of headache in MMA remains unclear but is likely multifactorial, involving impaired cerebrovascular autoregulation, microvascular ischemia, and collateral vessel development. No standardized treatment exists for MMA-related headache. Antiplatelet therapy, particularly aspirin, may offer some benefit, whereas NSAIDs and triptans require caution due to cerebrovascular risks. Emerging therapies such as calcitonin gene-related peptide (CGRP) inhibitors and Lasmiditan show potential but lack specific data in MMA patients. Surgical revascularization, mainly through direct or combined bypass, is an established intervention for stroke prevention and may also reduce headache burden. However, postoperative outcomes are heterogeneous, with reports of both headache improvement and new-onset headache. DISCUSSION AND CONCLUSION:Headache is a frequent and clinically relevant manifestation of MMA that significantly impacts quality of life. Evidence on optimal management remains scarce, and current strategies are largely empirical. Further studies are needed to clarify pathogenic mechanisms, refine patient selection for surgical interventions, and evaluate pharmacological treatments, including novel agents, to improve clinical outcomes.

Background Clinical observations indicated that vaccine-induced immune thrombosis with thrombocytopenia (VITT)-associated cerebral venous sinus thrombosis (CVST) often has a space-occupying effect and thus necessitates decompressive surgery (DS). While comparing with non-VITT CVST, this study explored whether VITT-associated CVST exhibits a more fulminant clinical course, different perioperative and intensive care unit management, and worse long-term outcome. Methods This multicenter, retrospective cohort study collected patient data from 12 tertiary centers to address priorly formulated hypotheses concerning the clinical course, the perioperative management with related complications, extracerebral complications, and the functional outcome (modified Rankin Scale) in patients with VITT-associated and non-VITT CVST, both with DS. Results Both groups, each with 16 patients, were balanced regarding demographics, kind of clinical symptoms, and radiological findings at hospital admission. Severity of neurological symptoms, assessed with the National Institute of Health Stroke Scale, was similar between groups at admission and before surgery, whereas more patients with VITT-associated CVST showed a relevant midline shift (≥ 4 mm) before surgery (100% vs. 68.8%, p = 0.043). Patients with VITT-associated CVST tended to undergo DS early, i.e., ≤ 24 h after hospital admission ( p = 0.077). Patients with VITT-associated CVST more frequently received platelet transfusion, tranexamic acid, and fibrinogen perioperatively. The postoperative management was comparable, and complications were evenly distributed. More patients with VITT-associated CVST achieved a favorable outcome (modified Rankin Scale ≤ 3) at 3 months ( p = 0.043). Conclusions Although the prediction of individual courses remains challenging, DS should be considered early in VITT-associated CVST because an overall favorable outcome appears achievable in these patients.

Re-intervention, either transsphenoidal surgery or radiotherapy, is suggested in patients who are not in remission after primary surgery for acromegaly; however, the evidence is weak. We aimed to assess the remission rate after re-intervention, and complications compared to a comparison group who had undergone primary interventions only. Patients diagnosed with acromegaly between 2005–2021 at Oslo University Hospital were screened for inclusion. The study cohort included patients with two or more interventions. The comparison group included patients not in remission after primary surgery. Of 223 patients with acromegaly, 42 underwent re-interventions (study cohort). At diagnosis, median age was 38 (IQR 29–48) years and 41 patients (98

AbstractResistance breathing may restore cardiac output (CO) and cerebral blood flow (CBF) during hypovolemia. We assessed CBF and cerebral autoregulation (CA) during tilt, resistance breathing, and paced breathing in 10 healthy subjects. Blood velocities in the internal carotid artery (ICA), middle cerebral arteries (MCA, four subjects), and aorta were measured by Doppler ultrasound in 30° and 60° semi‐recumbent positions. ICA blood flow and CO were calculated. Arterial blood pressure (ABP, Finometer), and end‐tidal CO2 (ETCO2) were recorded. ICA blood flow response was assessed by mixed‐models regression analysis. The synchronization index (SI) for the variable pairs ABP–ICA blood velocity, ABP–MCA velocities in 0.005–0.08 Hz frequency interval was calculated as a measure of CA. Passive tilting from 30° to 60° resulted in 12% decrease in CO (p = 0.001); ICA blood flow tended to fall (p = 0.04); Resistance breathing restored CO and ICA blood flow despite a 10% ETCO2 drop. ETCO2 and CO contributed to ICA blood flow variance (adjusted R2: 0.9, p < 0.0001). The median SI was low (<0.2) indicating intact CA, confirmed by surrogate date testing. The peak SI was transiently elevated during resistance breathing in the 60° position. Resistance breathing may transiently reduce CA efficiency. Paced breathing did not restore CO or ICA blood flow.

BackgroundThe identification of modifiable risk factors for intracranial glioma remains a significant challenge. While lifestyle factors and metabolic syndrome are well-established risk factors for various other cancers, their association with glioma risk remains unclear.ObjectivesThis study aims to conduct a comprehensive analysis of lifestyle factors and metabolic factors in relation to glioma risk.MethodsThe Cohort of Norway (CONOR) is a prospective, population-based health survey encompassing anthropometric measurements, blood tests and health questionnaires. CONOR data were linked to the National Cancer Registry to identify incident glioma cases. Follow-up time was calculated in person-years from the baseline examination until the date of glioma diagnosis, death, or the end of the follow-up period. Cox proportional hazards regression was used to calculate hazard ratios (HR).ResultsThe study cohort included 160,938 women and men. Over 2.8 million person-years of follow-up, 319 intracranial gliomas were diagnosed. Lifestyle factors such as physical activity, alcohol consumption, smoking, and marital status were not associated with glioma risk. There was no increased glioma risk among participants with diabetes mellitus or hypertension. Furthermore, metabolic syndrome in both women and men was not associated with an elevated risk of glioma. Blood lipids, including total cholesterol, triglycerides, and HDL, were not linked to glioma risk. However, increasing LDL levels were associated with a decreased risk of glioma in men (HR per category 0.84; 95% CI 0.74-0.96), but not in women.ConclusionThis is the first comprehensive prospective cohort study to evaluate potentially modifiable risk factors for glioma. Our findings do not support previously suggested associations between smoking, alcohol consumption, or metabolic syndrome and glioma risk.

Background In acromegaly, the primary tumor is usually found during magnetic resonance imaging (MRI) of the pituitary gland. A remnant tumor after surgery is, however, harder to depict. When a tumor is missed, the remaining option is usually lifelong pharmacological treatment. Purpose To identify tumors by reassessment of all available MRI scans in pharmacologically treated patients, operated or not, and to compare our results with the routine MRI reports. Material and Methods Adult patients diagnosed with acromegaly and managed at a tertiary care center between 2005 and 2021 and currently on pharmacological treatment were included. MRI scans were evaluated in a standardized manner and classified independently by a radiologist and an endocrinologist into “certain,” “suspected,” or “no tumor.” In case of disagreement, consensus was achieved with a senior neuroradiologist. The results were compared using the clinical radiologists’ routine MRI reports. Results We identified certain and suspected tumors in 29/74 and 36/74 patients, respectively. No tumor was identified in nine patients. In five of these, no MRI contrast agent was given. Discrepancy between our results and the routine MRI reports was found in 31/74 patients ( P = 0.01). In 22 patients, the routine reports described no tumor while we identified certain tumors in 2/22 patients and suspected tumors in 13/22 patients. Conclusion In most patients with pharmacologically treated acromegaly, we identified a certain or suspected pituitary tumor. These findings were more frequent compared to the routine MRI reports. Based on our results, patients will be considered for a change in long-term treatment modality.

Intraoperative aneurysm rupture (IAR) is a feared complication and an unnerving experience for any neurosurgeon. If not managed properly, the consequences may be devastating. Although overall patient outcomes in IAR have been shown to improve with a neurosurgeon's experience, the likelihood of rupture does not necessarily decrease, and the key to success lies in appropriate management. Microsurgical dexterity, remaining calm and acting sensible are important skills that all neurosurgeons need to master early on in order to achieve good patient outcomes. The landscape of cerebrovascular disease management has evolved significantly, with a growing preference for endovascular approaches. Consequently, the case-load of microsurgical procedures available for trainees have been diminished. As microsurgical cases decline and the remaining cases become more complex, the need for a systematic approach to IAR management becomes critical, to ensure a swift and efficient response and to compensate for reduced experience. This video article aims to empower the next generation of neurosurgeons by emphasizing essential skills and a systematic algorithmic approach required to navigate IAR situations successfully. In this video, we present the unedited sequence of IAR management in a posterior communicating artery (PCoA) aneurysm, from rupture to clipping. A 43-year-old female patient presented with headache and diplopia caused by a left oculomotor nerve palsy. Computed tomography (CT) did not show subarachnoid hemorrhage, but CT angiogram revealed a 7-mm left PCoA aneurysm affecting the oculomotor nerve. Patient consent was obtained for surgical management. The predissection phase was uneventful, however during dissection of the aneurysm neck, IAR occurred from the aneurysm dome. One contributing factor to rupture may have been the traction exerted on the aneurysm with the dissector, possibly due to adhesion of the aneurysm dome to the tentorial edge. Additionally, performing intradural drilling of the anterior clinoid process during the approach could have provided better access to proximal control of the internal carotid artery, making clip application easier. By remaining calm and proceeding with the steps illustrated in the decision algorithm (Fig. 1), the right actions were made, and the aneurysm was successfully clipped. In this article, we provide early career vascular neurosurgeons with a systematic strategy for managing IAR, offering guidance that may facilitate the 'right move' during these high-stress situations.

BackgroundMeningioma is the most common primary brain tumor, with a clear preponderance in women. Obesity is considered a risk factor for the development of meningioma. Obesity is also the clinical hallmark of metabolic syndrome, characterized by glucose intolerance, dyslipidemia, and hypertension. Lifestyle and metabolic factors directly impact overweight and obesity and are therefore potential risk factors for meningioma development. The aim of this study is to assess lifestyle and metabolic factors for meningioma risk in women.MethodsThe Cohort of Norway (CONOR) is a nationwide health survey, conducted between 1994 and 2003, including anthropometric measures, blood tests, and health questionnaires. Linkage to the National Cancer Registry enabled the identification of intracranial meningioma during follow-up until December 2018.ResultsA total of 81,652 women were followed for a combined total of 1.5 million years, and 238 intracranial meningiomas were identified. Increasing levels of physical activity (HR 0.81; 95% CI 0.68–0.96; p trend <0.02) and parity (HR 0.83; 95% CI 0.71–0.97; p trend <0.03) were negatively associated with meningioma risk. Diabetes mellitus or glucose intolerance increased the risk for meningioma (HR 2.54; 95% CI 1.60–4.05). Overweight and obesity were not associated with meningioma risk, nor was metabolic syndrome. However, participants without metabolic dysfunction had a reduced meningioma risk, while participants with all five metabolic factors present had a 4-fold risk increase for meningioma (HR 4.28; 95% CI 1.34–13.68).ConclusionLifestyle factors seem to significantly influence meningioma risk. However, disentangling the complex associations and interactions between factors for meningioma risk will be a challenging task for future studies.

Tumours in the pituitary fossa region can be resected by endoscopic transnasal surgery using a four-hands technique. The technique, which is atraumatic, safe and minimally invasive, should be the first-line treatment for pituitary tumours and certain skull-base tumours.

Increased levels of neutrophil extracellular traps (NETs) have been detected in individuals with vaccine complications after the ChAdOx1 nCov vaccine with a correlation between the severity of vaccine side effects and the level of NETosis. DNases may disrupt NETs by degrading their content of DNA, and a balance has been reported between NETs and DNases. Because of this and since the inflammatory marker NETs may be used as a confirmatory test in diagnosing VITT, it is of interest to monitor levels of DNase in patients with increased NETs levels. The current novel rapid DNase ELISA was tested in blood samples of patients with known increased levels of NETs with or without VITT after ChAdOx1 nCoV-19 vaccination. DNase levels in VITT patients were significantly increased compared with normal unvaccinated blood donors and compared with patients with post-vaccination symptoms but not VITT. However, since EDTA was found to inhibit DNase, serum and not EDTA-plasma samples should be applied for DNase testing. The novel DNase assay may serve as a supplementary test to the NETs test when analysing samples from patients with suspected increased NETs levels.