Journal of the Neurological Sciences

Background: Spontaneous intracerebral hemorrhage (ICH) has high disability and mortality. Accurate early prognostication remains challenging in routine practice. Conventional CT assessment relies mainly on hematoma volume and rough anatomical location, limiting individualized prognosis. Radiomics combined with machine learning may improve prognostic assessment by extracting quantitative texture and heterogeneity features.Methods: In this retrospective multicenter study, we included 2,680 consecutive patients with spontaneous ICH: training (n=1,876), internal validation (n=804), and independent external validation (n=196). Deep learning automatically segmented hematomas, and 1,690 radiomics features were extracted from admission non-contrast CT (NCCT). After reproducibility assessment, univariate screening, and LASSO selection, 42 features were integrated into a Rad-score. The Rad-score was combined with demographic, clinical, and conventional CT variables to construct two complementary machine learning models for functional outcome prediction and comprehensive prognostic stratification. Performance was assessed using R2, mean squared error (MSE), area under the receiver operating characteristic curve (AUC), calibration, decision curve analysis, and external validation. Both models were internally and externally validated. Ambient temperature variation at symptom onset was explored as a potential prognostic modifier. Results: Forty-two reproducible radiomics features constituted the Rad-score. Adding radiomics substantially improved performance over conventional clinical and imaging models. For functional outcome prediction, the integrated model increased R2 from 0.35 to 0.93 and reduced MSE from 387 to 61. For prognostic risk stratification, the clinical-only model achieved an AUC of 0.59, whereas the fully integrated model achieved 0.95 and maintained robust external performance (AUC=0.86). Conclusions: We developed and validated a machine learning-based clinical decision support system integrating conventional CT radiomics and clinical variables for prognostic prediction and risk stratification in ICH. By capturing quantitative imaging information beyond conventional CT markers, this framework improved prognostic discrimination and generalizability. These findings support integrating quantitative imaging biomarkers into clinical decision-making for spontaneous ICH. The association between ambient temperature variation and disease progression warrants prospective investigation. Further prospective validation is warranted.

Background/Aims: Pre-stroke depression has been shown to be associated with worse functional outcomes and depression after stroke. However, it is not currently well understood whether pre-stroke mood disorders (e.g., depression, anxiety, mood and psychotic disorders, substance use disorder) are associated with withdrawal of life-sustaining treatment (WOLST) after a severe stroke. Methods: This was a retrospective cohort study within the Tufts Vascular Neurology Registry of patients hospitalized with severe acute ischemic stroke (AIS, defined as NIHSS [≥]10) or severe nontraumatic intracerebral hemorrhage (ICH, defined as ICH score [≥]2) between 2018 and 2022. Multivariate logistic regression was performed to identify predictors of WOLST. Results: This study included 405 patients with severe stroke. Patients who opted for WOLST were more likely to be older, female, have AIS, and experience more severe strokes. In an adjusted analysis (basic demographics, stroke type), a pre-stroke mood disorder was associated with WOLST (OR 2.15, 95% CI 1.11-4.15). In models stratified by stroke type (AIS vs. ICH) and adjusted for stroke severity, WOLST was associated with age in both groups and with mood disorder in patients with ICH. The WOLST event rate was higher in the ICH group (19% vs 11%). Conclusion: Pre-stroke mood disorder was associated with increased rates of withdrawal of care after severe stroke in this patient population. Opportunities to actively treat depression may be useful to include in goals of care discussions to mitigate the potential impact of this factor in decision-making. Consistent with prior studies, we observed a higher proportion of WOLST in older, female, and ICH patients. Future studies regarding the quality and content of goals of care discussions may help elucidate the differing effects of pre-stroke mood disorders on WOLST by stroke type seen in this study.

Background and Objectives Transient ischemic attack (TIA) diagnosis is challenging because it relies mainly on clinical assessment and exclusion of common differential. Functional MRI (fMRI) may provide a diagnostic biomarker by detecting transient brain dysfunction not visible on conventional imaging. This pilot study aimed to characterize acute motor-task BOLD activation in patients with suspected DWI-negative TIA and compare functional patterns between confirmed TIA and alternative diagnoses. Secondary objectives were to assess longitudinal changes in activation and connectivity at 3 months. Methods In this prospective single-center study, adults presenting within 24 h of transient anterior-circulation neurological symptoms underwent conventional MRI and additional motor-task fMRI. Patients with acute DWI lesions were excluded. Final diagnosis was established after 3-month follow-up. Whole-brain analyses, individualized motor cortex region-of-interest (ROI) analyses, and generalized psychophysiological interaction (gPPI) connectivity analyses were performed during the acute phase and at 3 months. Results Eight patients were enrolled; six had complete longitudinal imaging data and were included in the final analyses. Final diagnoses were TIA (n=2), migraine aura (n=2), functional neurological disorder (n=1), and hypoglycemia (n=1). Whole-brain and ROI analyses showed reduced bilateral motor-related BOLD responses during the acute phase in both TIA patients and in the patient with hypoglycemia. In contrast, patients with migraine and functional neurological disorder exhibited less marked longitudinal changes. In TIA patients, motor cortex activation increased at 3 months, tending to normalize toward values observed in non-TIA participants. Connectivity analyses revealed heterogeneous patterns, but the 2 TIA patients demonstrated increased longitudinal connectivity between the motor cortex contralateral to symptoms and other sensorimotor regions, including supplementary motor, premotor, parietal, and postcentral cortices. Discussion These preliminary findings suggest that TIA may be associated with transient bilateral reductions in motor-network activity. Functional abnormalities appeared to improve over time, supporting the hypothesis of reversible network dysfunction. Although limited by the very small sample size, this study provides the first longitudinal assessment of emergency task-based fMRI in rigorously defined TIA and supports further investigation of acute functional MRI as a potential biomarker of transient cerebral dysfunction.

Introduction: Hematoma expansion is a main cause of early worsening after spontaneous intracerebral hemorrhage (ICH). Many hospitals in low income countries have no invasive pressure monitoring and no automated pupillometer. Staff use the Glasgow Coma Scale (GCS) and a penlight to check the pupils, and pupil changes seen with a penlight usually come late. The speed of pupil constriction may change earlier, and smartphones record video fast enough to measure it. Methods and analysis: This will be a single-centre prospective cohort study of 120 adults with ICH on non-contrast computed tomography (NCCT) who arrive within 24 hours of symptom onset. At admission and every 6 hours until 48 hours, we will record a 6 second smartphone video of each eye reacting to a flash, using an eyecup that blocks ward light. Open-source software will measure the pupil diameter in every frame. The main measure is constriction velocity (CV). The primary outcome is hematoma expansion (an increase of more than 6 mL or more than 33%) on NCCT at 24 hours. Secondary outcomes are a fall of 2 or more GCS points within 48 hours and in-hospital death. The primary analysis estimates the area under the receiver operating characteristic curve for the percentage fall in CV from each patient's first recording. Ethics and dissemination: Patients or their legal representatives will give written consent. Results will be submitted to a peer-reviewed journal, and the analysis code will be made public.

Background and objectives: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is the most common monogenic cerebral small vessel disease. Though neuropsychiatric symptoms (NPS) of CADASIL profoundly impact function and quality of life, these symptoms remain understudied. This analysis characterizes the prevalence, severity, and profile of NPS among individuals with CADASIL-causing NOTCH3 variants and non-carrier biological family controls in the United States CADASIL Consortium (USCC). Methods: This cross-sectional analysis used multimodal baseline data from 12 enrollment sites across the country. Statistical analyses used nonparametric tests and regression models to compare clinical and neuropsychiatric outcomes across CADASIL risk tiers and controls, adjusting for age, sex, race, and education where appropriate. The primary outcome measure was the Neuropsychiatric Inventory Questionnaire (NPI-Q), an informant-reported measure which assesses 12 categories of NPS. NPI-Q item severity and distress were evaluated for individuals with confirmed cysteine-altering NOTCH3 variants and compared with controls. Results: Four hundred fifty-nine USCC participants were included in the analytic cohort: 343 cases [256 high-risk (HR); 63 medium-risk (MR); 24 low-risk (LR)]; and 116 controls. Among participants with available NPI-Q data, at least one neuropsychiatric symptom was reported by 72.6% (n = 228/314) of cases compared with 53.2% (n = 58/109) of controls. Reported symptoms were more common among CADASIL cases than controls, occurring in 75.0%, 71.2%, and 72.7% of participants in the LR, MR, and HR groups, respectively, compared with 53.2% of controls. Compared with controls, participants in the MR group and HR group had higher NPI-Q severity scores. HR participants also had higher NPI-Q distress scores than controls. Discussion: Our findings support the notion that NPS are an important clinical manifestation of CADASIL. Beyond previously reported symptoms, additional neuropsychiatric manifestations were identified. Given the higher burden and variability in the neuropsychiatric presentation of CADASIL, the relationships among neuropsychiatric, neurological, and patient-reported outcomes merit further investigation. The NPS profile may enhance the evaluation of the safety and efficacy of different treatments to target these symptoms for CADASIL patients. Trial Registration Information: The study is registered at ClinicalTrials.gov (NCT05677880, 12/12/2022).

Introduction: Neuroinflammation is a known pathophysiologic mechanism in multiple sclerosis and a proposed mechanism in fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Positron Emission Tomography (PET) imaging of the translocator protein (TSPO) has been widely used to measure neuroinflammation, though second-generation ligands are highly sensitive to a single nucleotide polymorphism, rs6971, resulting in high, mixed, and low affinity binders. It is unknown whether this polymorphism is associated with neuroinflammatory disorders. Materials and Methods: Eighty-six total participant genotypes for TSPO binding affinity were identified through Sanger sequencing (30 fibromyalgia, 21 ME/CFS, 11 multiple sclerosis, and 24 healthy controls). Associations between patient group and genotype were assessed with Fishers Exact test. Associations between genotype and symptom severity from self-report questionnaires were assessed with Kruskal-Wallis tests. Results: In the present study individuals with fibromyalgia, (ME/CFS), or multiple sclerosis were more likely to have a mixed- or low-affinity genotypes compared to healthy controls. Presence of the low or mixed genotypes were also associated with greater self-reported fatigue severity and depressive symptoms. Discussion: These findings should be confirmed in larger samples but suggest functional consequences of rs6971 polymorphism that may be related to the pathophysiology of pain and fatigue illnesses.

Background: Dexmedetomidine (DEX) and midazolam (MDZ) are commonly used agents for conscious sedation in patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). While DEX offers superior sedation quality and potential neuroprotective effects, it is also associated with risk of hemodynamic instability. High-quality evidence directly comparing their impact on functional outcomes after EVT is lacking. This trial aims to determine whether conscious sedation with DEX, compared to MDZ, improves functional outcomes in patients with AIS due to anterior circulation large vessel occlusion (LVO) undergoing EVT. Methods: PEACE (Dexmedetomidine versus Midazolam for Conscious Sedation during Endovascular Stroke Thrombectomy) is a prospective, randomized, open label, blinded-endpoint, multicenter trial. Up to 810 patients with AIS due to LVO in the anterior circulation within 24 hours of last known well will be randomly assigned in a 1:1 ratio to receive either DEX or MDZ for conscious sedation during EVT across 30 centers in China. Results: The primary end point is the proportion of patients achieving a modified Rankin Scale (mRS) score 0-2 at 90 days, analyzed in the intention-to-treat population using a modified Poisson regression model, with results expressed as a risk ratio. Key secondary outcomes include the ordinal distribution of mRS scores at 90 days, and successful recanalization. Safety outcomes include symptomatic intracranial hemorrhage within 48 hours, and mortality at 90 days. Conclusion: The PEACE trial will provide definitive, high-level evidence on the comparative efficacy and safety of DEX versus MDZ for conscious sedation during EVT in patients with AIS due to LVO in the anterior circulation, with the goal of guiding clinical practice.

Background Accurate prediction of 90-day outcomes following ischemic stroke is crucial for optimizing clinical strategies. This study aimed to systematically review and meta-analyze studies using deep learning (DL) and hand-crafted radiomics (HCR) models for predicting 90-day modified Rankin Scale (mRS) outcomes after ischemic stroke. Methods We followed the PRISMA guidelines for systematic reviews. Four databases (PubMed, Embase, Web of Science, and Cochrane Library) were searched comprehensively for studies published up to September 2025. Inclusion criteria encompassed original research focusing on ischemic stroke patients with mRS at 90 days as the primary outcome and predictive models utilizing imaging biomarkers from CT or MRI. Quality assessment of the included studies was conducted using the PROBAST and and METhodological RadiomICs Score (METRICS) tools. Results Seventeen studies were included in the quantitative meta-analysis. Models demonstrated good prognostic performance for 90-day outcomes, with pooled AUCs of 0.85 (95% CI: 0.80-0.86) for internal and 0.74 (95% CI: 0.67-0.89) for external validation sets, with no significant difference (p=0.42). Deep learning and hand-crafted radiomics models showed comparable diagnostic accuracy in the primary analysis (p=0.667); a difference in sensitivity favouring hand-crafted radiomics emerged only in a post-hoc analysis after exclusion of one outlier study. Models incorporating clinical variables significantly outperformed imaging-only models (p<0.01). CT- and MRI-based models showed similar performance. Treatment-specific analyses revealed higher sensitivity for IVT-based models and higher specificity for combined MT+IVT models. Conclusions DL and HCR models demonstrate robust potential for predicting 90-day outcomes in ischemic stroke. Future research should focus on standardizing model evaluation metrics and incorporating explainable AI techniques to improve clinical applicability.

Introduction Mechanical thrombectomy has been well-established as the standard of care treatment for patients with moderate to severe acute ischaemic stroke secondary to large vessel occlusion. However, the clinical value of endovascular treatment (EVT) in patients presenting with minor stroke and low baseline National Institutes of Health Stroke Scale scores remains incompletely defined, with limited high-quality clinical evidence. This protocol outlines the methodology of a randomized trial designed to evaluate whether EVT combined with best medical therapy (BMT) achieves superior functional outcomes relative to BMT alone among patients with minor stroke. Methods and analysis Eligible patients with acute minor anterior circulation ischaemic stroke and confirmed large vessel occlusion (n=264) will be randomized via a computer generated block randomization sequence to receive either EVT plus BMT (intervention arm) or BMT alone (control arm). The primary efficacy outcome is the proportion of participants achieving excellent functional recovery, defined as a modified Rankin Scale score of 0 or 1 at 90 days. Primary safety outcomes comprise symptomatic intracranial haemorrhage within 48 hours after randomization (classified according to Heidelberg criteria) and all cause mortality at 90 days. Participants will be considered eligible if they satisfy all of the following inclusion criteria: (1) enrolment within 24 hours of stroke symptom onset or time last known well; (2) baseline NIHSS score of 2 - 5 accompanied by at least one focal neurological deficit (including altered consciousness, facial palsy, limb weakness, aphasia or hemispatial neglect); (3) angiographically confirmed acute occlusion of the intracranial internal carotid artery, the M1 segment of the middle cerebral artery, or a dominant M2 branch; (4) a hypoperfusion volume (Tmax >6s) [&ge;] 50mL on computed tomography or magnetic resonance perfusion imaging. Both intention to treat and per protocol analyses will be undertaken, and potential sources of heterogeneity in treatment effect magnitude will be explored. Ethics and Dissemination This study was approved by the ethnic committee from the First Affiliated Hospital of Wannan Medical University (2023-IRB90). The findings of this study will be disseminated through publication in peer-reviewed journals. Registration URL:https://www.clinicaltrial.gov; Unique identifier: NCT06143488.

Encephalopathy is a lethal manifestation of global cerebral dysfunction spanning hypoxic, metabolic, toxic, and vascular etiologies, yet its population burden is difficult to quantify because it predominantly appears as a contributing rather than underlying cause of death. Here, we analyzed US multiple-cause death records from 1999 through 2024 using harmonized CDC WONDER datasets. A longitudinally consistent core definition of 10 ICD-10 codes identified 953,846 encephalopathy-associated deaths. The national age-adjusted mortality rate increased 28.4%, from 9.143 per 100,000 in 1999 to 11.738 in 2024, after peaking at 14.391 in 2021. Segmented log-linear regression identified four temporal phases: 1999-2004 (annual percent change [APC],-1.76%), 2004-2018 (APC, 2.57%), 2018-2021 (APC, 6.54%), and 2021-2024 (APC, -5.98%). Encephalopathy was listed as the underlying cause in only 21.6% of deaths in 2024. Unspecified encephalopathy surged more than 3.6-fold, while anoxic brain injury remained stable. Mortality remained higher in males than females (13.973 versus 9.778 per 100,000), and rates among non-Hispanic Black individuals were 1.90-fold those of non-Hispanic White individuals. Geographically, mortality clustered in the Midwest and South (13.144 and 13.120 per 100,000 in 2024), with persistent state-level dispersion across the study period. COVID-19 accounted for 10.9% of associated deaths in 2021 before falling to 1.4% in 2024. These findings reveal a nonlinear trajectory shaped by diagnostic shifts, pandemic disruption, and persistent demographic and geographic disparities.

Disorders of consciousness (DoC) are characterised by marked reductions in cerebral glucose metabolism, but the specific cellular and neurochemical processes driving this impairment remain unclear. To elucidate these mechanisms, a multimodal imaging approach combining [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance spectroscopy (MRS) was applied to the posterior medial cortex (PMC) in 15 DoC patients and 14 healthy controls. Regional FDG metabolic index (FDG-MI) values and MRS concentration estimates of glutamate plus glutamine (Glx), {gamma}-aminobutyric acid (GABA+), total N-acetylaspartate (tNAA), total creatine (tCr), and total choline (tCho) were compared between groups and evaluated against Coma Recovery Scale-Revised (CRS-R) scores at baseline and follow-up (mean 127 days). Patients demonstrated reductions within the PMC in Glx, tCr, and tNAA concentrations, as well as a reduced Glx/GABA+ ratio. Local FDG-MI was substantially reduced in patients and correlated positively with tNAA and tCr. Furthermore, baseline tCho concentrations positively predicted long-term clinical recovery, as indexed by changes in CRS-R scores at follow-up. These findings suggest that macroscopic glucose hypometabolism in DoC may be linked to disrupted intracellular mitochondrial energy production pathways and a shift towards relative synaptic inhibition in the PMC. Moreover, the association between choline levels and behavioural recovery may point to the relevance of retained structural synthesis capacity for functional outcomes.

Sex differences in mortality after traumatic brain injury (TBI) have been inconsistently reported, even after accounting for age, injury severity, and other injury related factors. Understanding the sources of this heterogeneity is important for prognostic research and the development of data-driven clinical decision-support tools. We conducted a systematic review and meta-analysis of sex-specific mortality after adult TBI and used explainable machine learning (ML) to investigate potential modifiers of between-study effect estimates. We searched eight databases from inception to August 25, 2025, for studies reporting mortality estimates adjusted for at least age and injury severity. Risk of bias was assessed using the Quality in Prognosis Studies tool. Male-to-female mortality estimates were pooled using random-effects meta-analysis. Three explainable ML algorithms were used to identify important modifiers of study-level effect estimates. Among 9,418 records identified, 21 studies comprising 899,813 participants and 98,286 deaths met the inclusion criteria. Pooled analyses showed lower mortality among females than males (OR 0.88, 95% CI 0.80-0.98; HR 0.76, 95% CI 0.59-0.98). Lower mortality among females was also observed for in-hospital mortality (OR 0.86, 95% CI 0.76-0.97) and overall or unspecified mortality (OR 0.83, 95% CI 0.78-0.88). Substantial residual heterogeneity remained across analyses. Explainable ML identified mean age, study sex composition, and study quality as important modifiers of reported effect estimates. These findings were consistent across sensitivity analyses. Female sex was associated with lower mortality after adult TBI, although substantial between-study heterogeneity remained. Explainable ML identified demographic and methodological factors that may contribute to variation in reported associations. These findings highlight the importance of population characteristics and study context when developing, validating, and interpreting explainable digital prognostic tools for TBI. PROSPERO: CRD420251252136.

Abstract Background: Despite the high stroke burden in the elderly, their thrombolysis utilization is suboptimal partly due to heightened hemorrhagic risk. Observational data suggest that low-dose thrombolysis may offer comparable efficacy to standard-dose with a trend toward reduced symptomatic intracranial hemorrhage (sICH), yet high-level evidence for low-dose thrombolysis in this broad population remains absent. Objective: To evaluate the safety and efficacy of low-dose intravenous tenecteplase thrombolysis in elderly stroke patients within 4.5 hours of ischaemic stroke onset. Methods and design: The DATE-AGING trial is a multicenter, prospective, randomized, open-label, blinded-end point (PROBE) non-inferiority study. Eligible participants are elderly patients (aged [&ge;]70 years)with acute ischemic stroke who meet current guideline recommendations for intravenous thrombolysis within 4.5 hours of symptom onset will be randomly assigned to Low-dose Tenecteplase group (0.175 mg/kg, max 17.5 mg) or Standard-dose Tenecteplase group (0.25 mg/kg, max 25 mg). The primary outcome was excellent functional outcome, defined as a mRS 0-1 assessed at 90-day post-randomization. Safety outcomes included sICH within 36 hours and mortality at 90 days. Discussions: The DATE-AGING trial is intended to provide high-quality evidence for low-dose tenecteplase intravenous thrombolysis in elderly patients with acute ischemic stroke. Trial registry number: NCT07294209(https://clinicaltrials.gov/study/07294209). Keywords: elderly patients, acute ischemic stroke, intravenous thrombolysis, low-dose tenecteplase

Background: Secondary progressive multiple sclerosis (SPMS) is traditionally viewed as predominantly neurodegenerative, with limited inflammatory activity. However, chronic active lesions characterised by persistent rim inflammation and gradual expansion may continue to contribute to tissue injury. Objectives: To characterise chronic lesion dynamics in SPMS and determine whether chronic lesion expansion contributes to tissue damage and neurodegeneration. Thirty-one patients with SPMS underwent longitudinal MRI including T1-weighted, FLAIR and diffusion imaging. White matter lesions were manually segmented and chronic lesion tissue expansion (CLTE) was quantified as annualised percentage change. Associations between lesion expansion, mean diffusivity (MD) changes and brain atrophy were assessed using correlation, regression and mixed-effects modelling. Results: CLTE remained prominent, with a mean annual expansion rate of 7.1 +- 4.1%. Expansion substantially exceeded the contribution of newly formed lesions and occurred at rates comparable to relapsing multiple sclerosis. CLTE demonstrated moderate intra-patient clustering (ICC = 0.23). MD increased significantly within lesions during follow-up and was associated with lesion expansion. Chronic lesion expansion was also strongly associated with ventricular enlargement (partial r = 0.72, p < 0.001). Conclusions: Chronic lesion expansion persists in SPMS and represents a major source of tissue injury associated with microstructural degeneration and brain atrophy.

Abstract Background The neuropsychiatric sequelae (cognitive deficits, anxiety and depression) post-COVID-19 exist as part of the spectrum of the multisystemic long COVID. People with these symptoms have been shown to have worse functional outcomes. Hence, this significantly impacts the economy, primarily due to productivity losses. Yet, the precise underlying pathogenesis remains unknown, as do any diagnostic or prognostic biomarkers. Aim This study aims to identify functionally impacted brain regions in those with post-COVID-19 neurological sequelae and to evaluate how alterations in brain function relate to acute serum inflammatory mediators and brain injury biomarkers. Methods The study will utilise data from the COVID-19 Clinical Neuroscience Study (CNS), a large UK multicentre study conducted during the pandemic. This sub-study will be a secondary analysis of the COVID-19 CNS, a prospective observational study that compared COVID-19-positive participants with negative controls. Participants had an MRI, blood tested for acute serum inflammatory mediators and brain injury biomarkers, and neuropsychiatric assessment (cognitron test, PHQ-9 and GAD-7) post-acutely and at follow-up. The DPABI (Data Processing & Analysis for Brain Imaging) toolbox will be used for pre-processing and analysis of the neuroimaging data (resting state functional MRI) to obtain regional homogeneity (ReHo). The association between ReHO and neuropsychiatric symptoms, acute inflammatory mediators and brain injury biomarkers will be explored. Regression models would be used to determine the risk and protective factors for developing these symptoms. Conclusion It is anticipated that the study will provide new insights into the functional basis of post-acute COVID-19 neuropsychiatric manifestations and identify new diagnostic biomarkers. Key words: Regional Homogeneity, COVID-19, functional MRI, neuropsychiatry, biomarkers

Background: The Central Brain Tumor Registry of the United States (CBTRUS) uses a histology grouping model based on the World Health Organization (WHO) to classify cancer registry records for clinically relevant statistical reporting. Methods: CBTRUS, together with its consulting neuropathologists, reviewed and aligned its histology groupings with the 2021 WHO Classification update. Obsolete histology nomenclature along with their International Classification of Diseases for Oncology 3rd edition (ICD-O-3) codes were identified, currently included histologies were reclassified as appropriate, and new codes found in 2021 WHO were incorporated. An evaluation was conducted of the frequency of histology codes affected in the reclassification process, as well as incidence and survival pre- and post- reclassification of CBTRUS Tumor Type Groupings. Results: After review of the CBTRUS grouping scheme, 205 codes were reclassified and 2 new codes were incorporated. Tumor type groups most affected were those classified as glioma. Reclassification resulted in 167,038 of 491,804 (34%) cases having a grouping reclassification or reporting change, indicating that the 2021 revision of the WHO Classification has significantly impacted the collection and reporting of primary b CNS tumors. Conclusion: This work demonstrates the need to be responsive to changes in classification and coding for statistics to reflect real-world clinical use. This will require collaboration from all parties to have the ability to reconcile clinical practices and surveillance requirements.

Background Endovascular treatment of unruptured intracranial aneurysms (UIAs) often requires dual antiplatelet therapy with aspirin and a P2Y12 inhibitor. Clopidogrel remains widely used, but variable bioactivation and high on-treatment platelet reactivity have prompted interest in alternatives such as prasugrel. We compared thromboembolic and hemorrhagic outcomes after clopidogrel versus prasugrel use in endovascular UIA treatment. Methods We queried the TriNetX Global Collaborative Network for adults with UIA who underwent endovascular treatment between 2016 and 2025 and received aspirin plus clopidogrel or prasugrel. Cohorts were matched 1:1 using propensity score matching based on demographics and comorbidities. Outcomes were assessed at 6 months and 1 year and reported as odds ratios (ORs) with 95% confidence intervals (CIs). Results Among 15,496 adults, 711 matched pairs were included. At 6 months, no significant differences were observed for in-stent thrombosis (OR 0.77, 95% CI 0.38?1.57; p=0.47), cerebral infarction (OR 1.04, 95% CI 0.75?1.46; p=0.80), cerebral hemorrhage (OR 1.07, 95% CI 0.80?1.44; p=0.65), or gastrointestinal hemorrhage (OR 0.84, 95% CI 0.43?1.64; p=0.61). Findings remained nonsignificant at 1 year. Conclusions In this propensity-matched TriNetX analysis, clopidogrel and prasugrel were not associated with significant differences in thromboembolic or hemorrhagic outcomes after endovascular UIA treatment. Prasugrel may be a reasonable alternative P2Y12 inhibitor in selected patients, including those with suspected or documented clopidogrel non-response.

White matter hyperintensities on brain magnetic resonance imaging are established markers of cerebral small vessel disease and typically associate inversely with brain volume in the general population, reflecting irreversible tissue loss. In Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy, a monogenic small vessel disease caused by NOTCH3 cysteine-altering mutations, white matter hyperintensities may instead reflect tissue water accumulation and perivascular space dilation rather than net structural damage. Whether this distinct pathophysiological relationship is detectable at population level among carriers of NOTCH3 cysteine-altering variants without clinically manifest disease remains unknown. We conducted a cross-sectional neuroimaging study using UK Biobank data acquired between 2014 and 2023. Among 44,943 participants with complete brain magnetic resonance imaging data (mean age 64 years +/- 8 years), 96 carried heterozygous NOTCH3 cysteine-altering variants within epidermal growth factor-like repeat domains 7 to 34 and 44,847 were non-carriers. White matter hyperintensity volume was automatically quantified and normalized to total intracranial volume. Brain parenchymal fraction was defined as combined gray and white matter volumes divided by total intracranial volume. Lacunes were manually assessed in all carriers. Linear regression and generalized additive models examined the association between white matter hyperintensity volume and brain parenchymal fraction stratified by genotype, adjusting for age, sex, lacune count, and vascular risk factors. NOTCH3 variant carriers showed markedly higher normalized white matter hyperintensity volume than non-carriers (0.83% versus 0.36%; P<10^-8) but only marginally higher brain parenchymal fraction (81.1% versus 80.5%; P=0.03). In non-carriers, white matter hyperintensity volume was inversely associated with brain parenchymal fraction (beta=-0.116% per 1% increase; P=3.10^-6). In contrast, NOTCH3 variant carriers demonstrated a positive association (beta=+0.51%; P=0.019), strengthened after adjusting for lacune count (beta=+0.61%; P=0.006). A significant genotype-specific interaction confirmed this divergence (P=0.036), persisting across age groups and after vascular risk factor adjustment. NOTCH3 cysteine-altering variant carriers identified at population level exhibit a fundamentally distinct white matter hyperintensity-brain volume relationship compared with non-carriers, consistent with lesions reflecting tissue water accumulation rather than irreversible structural loss at this early, predominantly preclinical disease stage. These findings establish that genetic context modifies neuroimaging biomarker interpretation in cerebral small vessel disease and underscore the need for genotype-aware approaches when evaluating white matter hyperintensities as markers of disease severity or progression.

Background: Idiopathic normal pressure hydrocephalus (iNPH) is a potentially treatable neurological disorder whose molecular basis remains incompletely understood. Metabolomic studies in iNPH are scarce and have focused largely on comparisons with other neurological disorders or on cerebrospinal fluid (CSF) alone. Consequently, the broader metabolic phenotype of iNPH and the extent to which CSF alterations are reflected in peripheral blood remain unclear. We therefore compared paired CSF and plasma metabolomic profiles from patients with iNPH and controls. Methods: Paired CSF and plasma samples from 10 patients with iNPH and 10 controls were analyzed via hydrophilic interaction liquid chromatography-mass spectrometry. After quality control and deduplication, 134 CSF and 149 plasma metabolites were quantified. Protein-normalized abundances were log2-transformed and analyzed via age-adjusted ordinary least-squares regression as the primary model, with group-only regression and Mann-Whitney U tests used for sensitivity analyses. Significance was defined as Benjamini-Hochberg q < 0.05 and |log2-fold change| larger or equal to log2(1.5). Results: Age-adjusted analysis revealed 56 altered CSF metabolites in iNPH patients, 34 of which were increased and 22 of which were decreased; 47 were also significantly altered according to the Mann-Whitney U test. The CSF phenotype encompassed energy and carnitine/acylcarnitine metabolism, redox and one-carbon/transsulfuration-associated metabolism, tryptophan-kynurenine metabolism, amino acid and nucleotide turnover, and neuronal- or membrane-associated metabolites. Prominent changes included increased succinate, 3-hydroxybutyrate, oxidized glutathione, cystathionine, kynurenine and kynurenic acid, together with decreased carnitine, short-chain acylcarnitines, methionine and ergothioneine. In plasma, 27 metabolites met the age-adjusted significance criteria, but only allantoin, N-formylmethionine, 3-hydroxybutyrate, N-acetylmethionine and kynurenic acid were also significant according to the Mann-Whitney U test. Global CSF-plasma effect-size concordance was moderate. The most consistent cross-compartment features were 3-hydroxybutyrate, N-formylmethionine and N-acetylmethionine. Conclusions: iNPH was associated with a broad and comparatively consistent CSF-centered metabolic phenotype, whereas plasma showed a smaller, partial and model-sensitive reflection of these alterations. These findings support altered energy substrate handling, redox and sulfur-associated metabolism, tryptophan-kynurenine metabolism and neuronal or membrane-associated metabolite handling as components of iNPH biology. These exploratory findings require validation in larger, longitudinal cohorts.

The Vanishing White Matter (VWM) Registry is a single-center database containing longitudinal survey data from >470 untreated patients with DNA- and MRI-confirmed VWM. VWM is a rare genetic disorder of the brain's white matter with an estimated live birth incidence of 1 per 100,000 and prevalence of 1.3 per 1,000,000 people in the Netherlands. The Registry represents a remarkably extensive collection of systematically gathered information on this disease, enabling crucial research into the natural history of VWM and providing a valuable resource for control arms in clinical trials. Data, initially collected on paper from 2004, have been maintained electronically since 2018, and include validated scales alongside a disease-specific customized questionnaire covering clinical, functional, and psychosocial domains. Survey packages, available in eight languages, are sent one to four times a year, depending on patient age. Built-in validity checks and review by pediatric and adult neurologists ensure data quality. The dataset is continuously updated with questionnaires expanding its scope, and structured for analysis and reuse in research on VWM.