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INTRODUCTION A significant number of patients who present with mild symptoms following large-vessel occlusion acute ischemic stroke (LVO-AIS) are currently considered ineligible for EVT. However, they frequently experience neurological deterioration during hospitalization. This study aimed to investigate the association between neurological deterioration and hemodynamic impairment by assessing steal phenomenon derived from blood oxygenation-level dependent cerebrovascular reactivity (BOLD-CVR) in this specific patient cohort. PATIENTS AND METHODS From the database of our single-center BOLD-CVR observational cohort study (June 2015-October 2023) we retrospectively identified acute ischemic stroke patients with admission NIHSS < 6, a newly detected large vessel occlusion of the anterior circulation and ineligible for EVT. Neurological deterioration during hospitalization as well as outcome at hospital discharge were rated with NIHSS score. We analyzed the association between these two outcomes and BOLD-CVR-derived steal phenomenon volume through regression analysis. Additionally, we investigated the discriminatory accuracy of steal phenomenon volume for predicting neurological deterioration. RESULTS Forty patients were included in the final analysis. Neurological deterioration occurred in 35% of patients. In the regression analysis, a strong association between steal phenomenon volume and neurological deterioration (OR 4.80, 95% CI 1.32-31.04, p = 0.04) as well as poorer NIHSS score at hospital discharge (OR 3.73, 95% CI 1.52-10.78, p = 0.007) was found. The discriminatory accuracy of steal phenomenon for neurological deterioration prediction had an AUC of 0.791 (95% CI 0.653-0.930). DISCUSSION Based on our results we may distinguish two groups of patients with minor stroke currently ineligible for EVT, however, showing hemodynamic impairment and exhibiting neurological deterioration during hospitalization: (1) patients exhibiting steal phenomenon on BOLD-CVR imaging

BACKGROUND AND AIMS Increasing data suggest that stress-related neural activity (SNA) is associated with subsequent major adverse cardiovascular events (MACE) and may represent a therapeutic target. Current evidence is exclusively based on populations from the U.S. and Asia where limited information about cardiovascular disease risk was available. This study sought to investigate whether SNA imaging has clinical value in a well-characterized cohort of cardiovascular patients in Europe. METHODS In this single-centre study, a total of 963 patients (mean age 58.4 ± 16.1 years, 40.7% female) with known cardiovascular status, ranging from 'at-risk' to manifest disease, and without active cancer underwent 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography between 1 January 2005 and 31 August 2019. Stress-related neural activity was assessed with validated methods and relations between SNA and MACE (non-fatal stroke, non-fatal myocardial infarction, coronary revascularization, and cardiovascular death) or all-cause mortality by time-to-event analysis. RESULTS Over a maximum follow-up of 17 years, 118 individuals (12.3%) experienced MACE, and 270 (28.0%) died. In univariate analyses, SNA significantly correlated with an increased risk of MACE (sub-distribution hazard ratio 1.52, 95% CI 1.05-2.19; P = .026) or death (hazard ratio 2.49, 95% CI 1.96-3.17; P < .001). In multivariable analyses, the association between SNA imaging and MACE was lost when details of the cardiovascular status were added to the models. Conversely, the relationship between SNA imaging and all-cause mortality persisted after multivariable adjustments. CONCLUSIONS In a European patient cohort where cardiovascular status is known, SNA imaging is a robust and independent predictor of all-cause mortality, but its prognostic value for MACE is less evident. Further studies should define specific patient populations that might profit from SNA imaging.

Background: Pain in the head and the face is highly prevalent but may have changed during the past years. This study aimed to analyze changes in the prevalence of pain in the head and the face in Switzerland from 1997 to 2017. Methods: This is a secondary analysis of data collected in the Swiss Health Surveys of 1997–2017. Included persons were 15 years and older. Besides studying demographic data, we analyze the item assessing the presence of “headache, pressure in the head, or facial pain” during the past 4 weeks. Percentages with their Wilson confidence intervals are reported for each response option of categorical variables. Moreover, we calculate the age‐standardized number of persons affected by the pain. Results: While 41% reported head and face pain in 1997, the proportion dropped to 31% in 2017. There was a decrease of 19.5% in women and 29.4% in men; after age standardization, the decrease was 16.5% in women and 25.4% in men. The most considerable numerical changes in the percentages of women with pain occurred in those aged 55–69 and 85 and above. In men, the changes were not limited to specific age groups. Conclusions: The proportion of people reporting headaches, pressure in the head, or facial pain has dropped in Switzerland from 1997 to 2017. However, in women, the prevalence diminished more strongly and consistently in the middle‐aged and the elderly than in the young.

BACKGROUND AND OBJECTIVES Cerebral small vessel disease (SVD) is the major cause of intracerebral hemorrhage (ICH). There is no comprehensive, easily applicable classification of ICH subtypes according to the presumed underlying SVD using MRI. We developed an MRI-based classification for SVD-related ICH. METHODS We performed a retrospective study in the prospectively collected Swiss Stroke Registry (SSR, 2013-2019) and the Stroke InvestiGation in North And central London (SIGNAL) cohort. Patients with nontraumatic, SVD-related ICH and available MRI within 3 months were classified as Cerebral Amyloid angiopathy (CAA), Deep perforator arteriopathy (DPA), Mixed CAA-DPA, or Undetermined SVD using hemorrhagic and nonhemorrhagic MRI markers (CADMUS classification). The primary outcome was inter-rater reliability using Gwet's AC1. Secondary outcomes were recurrent ICH/ischemic stroke at 3 months according to the CADMUS phenotype. We performed Firth penalized logistic regressions and competing risk analyses. RESULTS The SSR cohort included 1,180 patients (median age [interquartile range] 73 [62-80] years, baseline NIH Stroke Scale 6 [2-12], 45.6% lobar hematoma, systolic blood pressure on admission 166 [145-185] mm Hg). The CADMUS phenotypes were as follows: mixed CAA-DPA (n = 751 patients, 63.6%), undetermined SVD (n = 203, 17.2%), CAA (n = 154, 13.1%), and DPA (n = 72, 6.3%), with a similar distribution in the SIGNAL cohort (n = 313). Inter-rater reliability was good (Gwet's AC1 for SSR/SIGNAL 0.69/0.74). During follow-up, 56 patients had 57 events (28 ICH, 29 ischemic strokes). Three-month event rates were comparable between the CADMUS phenotypes. DISCUSSION CADMUS, a novel MRI-based classification for SVD-associated ICH, is feasible and reproducible and may improve the classification of ICH subtypes in clinical practice and research.

Symptomatic patients with ischemic stroke due to internal carotid artery (ICA) occlusion often present with compromised brain hemodynamic status involving substantially larger parts of the affected vascular territory than the ischemic core itself (1-3). Despite the fact that the “Extracranial-Intracranial” (EC-IC) Bypass Study Group and the “Carotid Occlusion Surgery Study” (COSS) failed to demonstrate a benefit of bypass in comparison to medical therapy (4,5), several studies showed a significant improvement in hemodynamic parameters after superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery was performed in carefully selected patients (6-9) and even a reduction in stroke recurrence (6). Analysis showed that the failure of the COSS trial (5) to show a benefit regarding ipsilateral 2-year stroke recurrence in patients undergoing cerebral bypass revascularization was likely caused by a failure of the semiquantitative, hemispheric oxygen extraction fraction (OEF) ratio method used in the trial than by the selection of the patients for bypass based on hemodynamic compromise (10). Therefore, alternative and especially quantitative imaging techniques are needed to assess hemodynamic status in patients with ischemic stroke due to ICA occlusion.

At present, the majority of the proposed Deep Learning (DL) methods provide point predictions without quantifying the model's uncertainty. However, a quantification of the reliability of automated image analysis is essential, in particular in medicine when physicians rely on the results for making critical treatment decisions. In this work, we provide an entire framework to diagnose ischemic stroke patients incorporating Bayesian uncertainty into the analysis procedure. We present a Bayesian Convolutional Neural Network (CNN) yielding a probability for a stroke lesion on 2D Magnetic Resonance (MR) images with corresponding uncertainty information about the reliability of the prediction. For patient-level diagnoses, different aggregation methods are proposed and evaluated, which combine the individual image-level predictions. Those methods take advantage of the uncertainty in the image predictions and report model uncertainty at the patient-level. In a cohort of 511 patients, our Bayesian CNN achieved an accuracy of 95.33% at the image-level representing a significant improvement of 2% over a non-Bayesian counterpart. The best patient aggregation method yielded 95.89% of accuracy. Integrating uncertainty information about image predictions in aggregation models resulted in higher uncertainty measures to false patient classifications, which enabled to filter critical patient diagnoses that are supposed to be closer examined by a medical doctor. We therefore recommend using Bayesian approaches not only for improved image-level prediction and uncertainty estimation but also for the detection of uncertain aggregations at the patient-level.

Aim: To compare safety and functional outcomes of intravenous thrombolysis (IVT) between females and males with acute ischaemic stroke (AIS) in relation to preadmission use of antiplatelets. Methods: Multicentre cohort study of patients admitted from 1 January 2014 to 31 January 2020 to hospitals participating in the Swiss Stroke Registry, presenting with AIS and receiving IVT. Primary safety outcome was in-hospital symptomatic intracerebral haemorrhage (sICH). Primary functional outcome was functional independence at 3 months after discharge. Multivariable logistic regression models were fitted to assess the association between sex and each outcome according to preadmission use of antiplatelets. Results: The study included 4996 patients (42.51 % females, older than males, median age 79 vs 71 years, p < 0.0001). Comparable proportions of females (39.92 %) and males (40.39 %) used antiplatelets before admission (p = 0.74). In total, 3.06 % females and 2.47 % males developed in-hospital sICH (p = 0.19), with similar odds (adjusted odds ratio, [AOR] 0.93, 95 % confidence interval, [CI] 0.63–1.39). No interaction was found between sex and preadmission use of either single or dual antiplatelets in relation to in-hospital sICH (p = 0.94 and p = 0.23). Males had higher odds of functional independence at 3 months (AOR 1.34, 95 % CI 1.09–1.65), regardless of preadmission use of antiplatelets (interaction between sex and preadmission use of either single or dual antiplatelets p = 0.41 and p = 0.58). Conclusion: No sex differences were observed in the safety of IVT regarding preadmission use of antiplatelets. Males showed more favourable 3-month functional independence than females; however, this sex difference was apparently not explained by a sex-specific mechanism related to preadmission use of antiplatelets.

In many medical applications, interpretable models with high prediction performance are sought. Often, those models are required to handle semistructured data like tabular and image data. We show how to apply deep transformation models (DTMs) for distributional regression that fulfill these requirements. DTMs allow the data analyst to specify (deep) neural networks for different input modalities making them applicable to various research questions. Like statistical models, DTMs can provide interpretable effect estimates while achieving the state-of-the-art prediction performance of deep neural networks. In addition, the construction of ensembles of DTMs that retain model structure and interpretability allows quantifying epistemic and aleatoric uncertainty. In this study, we compare several DTMs, including baseline-adjusted models, trained on a semistructured data set of 407 stroke patients with the aim to predict ordinal functional outcome three months after stroke. We follow statistical principles of model-building to achieve an adequate trade-off between interpretability and flexibility while assessing the relative importance of the involved data modalities. We evaluate the models for an ordinal and dichotomized version of the outcome as used in clinical practice. We show that both tabular clinical and brain imaging data are useful for functional outcome prediction, whereas models based on tabular data only outperform those based on imaging data only. There is no substantial evidence for improved prediction when combining both data modalities. Overall, we highlight that DTMs provide a powerful, interpretable approach to analyzing semistructured data and that they have the potential to support clinical decision-making.

Aim To compare safety and functional outcomes of intravenous thrombolysis (IVT) between females and males with acute ischaemic stroke (AIS) in relation to preadmission use of antiplatelets. Methods Multicentre cohort study of patients admitted from 1 January 2014 to 31 January 2020 to hospitals participating in the Swiss Stroke Registry, presenting with AIS and receiving IVT. Primary safety outcome was in-hospital symptomatic intracerebral haemorrhage (sICH). Primary functional outcome was functional independence at 3 months after discharge. Multivariable logistic regression models were fitted to assess the association between sex and each outcome according to preadmission use of antiplatelets. Results The study included 4996 patients (42.51 % females, older than males, median age 79 vs 71 years, p < 0.0001). Comparable proportions of females (39.92 %) and males (40.39 %) used antiplatelets before admission (p = 0.74). In total, 3.06 % females and 2.47 % males developed in-hospital sICH (p = 0.19), with similar odds (adjusted odds ratio, [AOR] 0.93, 95 % confidence interval, [CI] 0.63–1.39). No interaction was found between sex and preadmission use of either single or dual antiplatelets in relation to in-hospital sICH (p = 0.94 and p = 0.23). Males had higher odds of functional independence at 3 months (AOR 1.34, 95 % CI 1.09–1.65), regardless of preadmission use of antiplatelets (interaction between sex and preadmission use of either single or dual antiplatelets p = 0.41 and p = 0.58). Conclusion No sex differences were observed in the safety of IVT regarding preadmission use of antiplatelets. Males showed more favourable 3-month functional independence than females; however, this sex difference was apparently not explained by a sex-specific mechanism related to preadmission use of antiplatelets.