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BackgroundHemorrhagic transformation (HT) following reperfusion therapies is a serious complication for patients with acute ischemic stroke. Segmentation and quantification of hemorrhage provides critical insights into patients’ condition and aids in prognosis. This study aims to automatically segment hemorrhagic regions on follow-up non-contrast head CT (NCCT) for stroke patients treated with endovascular thrombectomy (EVT).MethodsPatient data were collected from 10 stroke centers across two countries. We propose a semi-automated approach with adaptive thresholding methods, eliminating the need for extensive training data and reducing computational demands. We used Dice Similarity Coefficient (DSC) and Lin’s Concordance Correlation Coefficient (Lin’s CCC) to evaluate the performance of the algorithm.ResultsA total of 51 patients were included, with 28 Type 2 hemorrhagic infarction (HI2) cases and 23 parenchymal hematoma (PH) cases. The algorithm achieved a mean DSC of 0.66 ± 0.17. Notably, performance was superior for PH cases (mean DSC of 0.73 ± 0.14) compared to HI2 cases (mean DSC of 0.61 ± 0.18). Lin’s CCC was 0.88 (95% CI 0.79–0.93), indicating a strong agreement between the algorithm’s results and the ground truth. In addition, the algorithm demonstrated excellent processing time, with an average of 2.7 s for each patient case.ConclusionTo our knowledge, this is the first study to perform automated segmentation of post-treatment hemorrhage for acute stroke patients and evaluate the performance based on the radiological severity of HT. This rapid and effective tool has the potential to assist with predicting prognosis in stroke patients with HT after EVT.

Culturally and linguistically diverse (CALD) communities are growing globally. Understanding patterns of cerebrovascular disease in these communities may improve health outcomes. We aimed to compare the rates of transient ischaemic attack (TIA), ischaemic stroke (IS), intracerebral haemorrhage (ICH), intracranial atherosclerosis (ICAD), and stroke risk factors in Vietnamese-born residents of South-Western Sydney (SWS) with those of an Australian-born cohort. A 10-year retrospective analysis (2011–2020) was performed using data extracted from the Health Information Exchange database characterising stroke presentations and risk factor profiles. The rates of hypertension (83.7% vs. 70.3%, p < 0.001) and dyslipidaemia (81.0% vs. 68.2%, p < 0.001) were significantly higher in Vietnamese patients, while the rates of ischaemic heart disease (10.4% vs. 20.3%, p < 0.001), smoking (24.4% vs. 40.8%, p < 0.001), and alcohol abuse (>1 drink/day) (9.6% vs. 15.9%, p < 0.001) were lower. The rates of ICAD and ICH were higher in Vietnamese patients (30.9% vs. 6.9%, p < 0.001 and 24.7% vs. 14.4%, p = 0.002). Regression analysis revealed that diabetes (OR: 1.86; 95% CI: 1.14–3.04, p = 0.014) and glycosylated haemoglobin (OR: 1.51; 95% CI: 1.15–1.98, p = 0.003) were predictors of ICAD in Vietnamese patients. Vietnamese patients had higher rates of symptomatic ICAD and ICH, with unique risk factor profiles. Culturally specific interventions arising from these findings may more effectively reduce the community burden of disease.

Introduction: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a rare genetic condition with a broad phenotypic presentation. This study aims to establish the first Australian cohort of individuals affected by CADASIL (AusCADASIL) and examine its clinical features and longitudinal course, and to investigate neuroimaging and blood biomarkers to assist in early diagnosis and identify disease progression. Methods: Participants will be recruited from six study centres across Australia for an observational study of CADASIL. We aim to recruit 150 participants with diagnosed CADASIL, family history of CADASIL or suspected CADASIL symptoms, and 150 cognitively normal NOTCH3 negative individuals as controls. Participants will complete: 1) online questionnaires on medical and family history, mental health, and wellbeing; 2) neuropsychological evaluation; 3) neurological examination and brain MRI; 4) ocular examination and 5) blood sample donation. Participants will have annual follow-up for 4 years to assess their progression and will be asked to invite a study partner to corroborate their self-reported cognitive and functional abilities.Primary outcomes include cognitive function and neuroimaging abnormalities. Secondary outcomes include investigation of genetics and blood and ocular biomarkers. Data from the cohort will contribute to an international consortium, and cohort participants will be invited to access future treatment/health intervention trials. Discussion: AusCADASIL will be the first study of an Australian cohort of individuals with CADASIL. The study will identify common pathogenic variants in this cohort, and characterise the pattern of clinical presentation and longitudinal progression, including imaging features, blood and ocular biomarkers and cognitive profile.

Introduction The benefit of additional reperfusion attempts in patients with partial angiographic reperfusion (TICI2b) is unknown. The PROCEED model predicts subsequent favorable occurrence of complete reperfusion (i.e. delayed reperfusion [DR]) at 24 hours after initial incomplete angiographic reperfusion at the conclusion of thrombectomy. This study aims to externally validate the PROCEED model using pooled data from multiple international trials that systematically performed follow‐up perfusion imaging. Methods Individual patient data for external validation were obtained from the EXTEND‐IA, EXTEND‐IA TNK part 1 and 2 trials (clinicaltrials.gov, unique‐identifier: NCT01492725, NCT02388061 and NCT03340493). The model’s primary outcome of interest was the occurrence of DR, defined as the absence of any focal perfusion deficit on follow‐up CT or MRI perfusion imaging maps, despite initial incomplete angiographic reperfusion on the final thrombectomy angiography series. The updated model’s performance was evaluated with discrimination, calibration and clinical decision curves. Results We analyzed 267 patients for the external validation, with median age of 74 (IQR 64 – 80), 44.2% were female and 62% had DR. The externally validated model had good discrimination (C‐statistic 0.81, 95% CI 0.72 – 0.86) and was well calibrated (intercept 0.22, 95% CI 0.18‐0.33 and slope 0.96, 95% CI 0.81‐1.23). With threshold probability of R=12% (i.e. 88% chance of having DR), pursuing additional reperfusion attempts to pursue complete angiographic reperfusion in a patient with high‐likelihood of DR were seven times worse (Cost:Benefit Ratio 1:7, Figure 1) than no further endovascular maneuver. In terms of standardized net reduction, the PROCEED model could reduce one in five unnecessary interventions without missing an intervention for any patient who would eventually have DR. Across a wide range of threshold probabilities, the model outperformed the scenario of the typical decision‐making process in the angiography suite, based on the current treatment guidelines. Conclusion The externally validated model had good predictive accuracy and discrimination. Depending on the acceptable risk threshold, the model may compliment clinical judgment of the treating physicians and inform on natural progression of untreated incomplete reperfusion.

BackgroundThere is increasing evidence that COVID-19 survivors are at increased risk of experiencing a wide range of cardiovascular complications post infection; however, there are no validated models or clear guidelines for remotely monitoring the cardiac health of COVID-19 survivors.ObjectiveThis study aims to test a virtual, in-home healthcare monitoring model of care for detection of clinical symptoms and impacts on COVID-19 survivors. It also aims to demonstrate system usability and feasibility.MethodsThis open label, prospective, descriptive study was conducted in South Western Sydney. Included in the study were patients admitted to the hospital with the diagnosis of COVID-19 between June 2021 and November 2021. Eligible participants after consent were provided with a pulse oximeter to measure oxygen saturation and a S-Patch EX to monitor their electrocardiogram (ECG) for a duration of 3 months. Data was transmitted in real-time to a mobile phone via Bluetooth technology and results were sent to the study team via a cloud-based platform. All the data was reviewed in a timely manner by the investigator team, for post COVID-19 related symptoms, such as reduction in oxygen saturation and arrhythmia.Outcome measureThis study was designed for feasibility in real clinical setting implementation, enabling the study team to develop and utilise a virtual, in-home healthcare monitoring model of care to detect post COVID-19 clinical symptoms and impacts on COVID-19 survivors.ResultsDuring the study period, 23 patients provided consent for participation. Out of which 19 patients commenced monitoring. Sixteen patients with 81 (73.6%) valid tests were included in the analysis and amongst them seven patients were detected by artificial intelligence to have cardiac arrhythmias but not clinically symptomatic. The patients with arrhythmias had a higher occurrence of supraventricular ectopy, and most of them took at least 2 tests before detection. Notably, patients with arrhythmia had significantly more tests than those without [t-test, t (13) = 2.29, p

Summary: Background: Intensive blood pressure lowering may adversely affect evolving cerebral ischaemia. We aimed to determine whether intensive blood pressure lowering altered the size of cerebral infarction in the 2196 patients who participated in the Enhanced Control of Hypertension and Thrombolysis Stroke Study, an international randomised controlled trial of intensive (systolic target 130–140 mm Hg within 1 h; maintained for 72 h) or guideline-recommended (systolic target 150 mm Hg) after thrombolysis treatment for acute ischaemic stroke between March 3, 2012 and April 30, 2018. Methods: All available brain imaging were analysed centrally by expert readers. Log-linear regression was used to determine the effects of intensive blood pressure lowering on the size of cerebral infarction, with adjustment for potential confounders. The primary analysis pertained to follow-up computerised tomography (CT) scans done between 24 and 36 h. Sensitivity analysis were undertaken in patients with only a follow-up magnetic resonance imaging (MRI) and either MRI or CT at 24–36 h, and in patients with any brain imaging done at any time during follow-up. This trial is registered with ClinicalTrials.gov, number NCT01422616. Findings: There were 1477 (67.3%) patients (mean age 67.7 [12.1] y; male 60%, Asian 65%) with available follow-up brain imaging for analysis, including 635 patients with a CT done at 24–36 h. Mean achieved systolic blood pressures over 1–24 h were 141 mm Hg and 149 mm Hg in the intensive group and guideline group, respectively. There was no effect of intensive blood pressure lowering on the median size (ml) of cerebral infarction on follow-up CT at 24–36 h (0.3 [IQR 0.0–16.6] in the intensive group and 0.9 [0.0–12.5] in the guideline group; log Δmean −0.17, 95% CI −0.78 to 0.43). The results were consistent in sensitivity and subgroup analyses. Interpretation: Intensive blood pressure lowering treatment to a systolic target

BackgroundHemorrhagic transformation (HT) following reperfusion therapies for acute ischaemic stroke often predicts a poor prognosis. This systematic review and meta-analysis aims to identify risk factors for HT, and how these vary with hyperacute treatment [intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT)].MethodsElectronic databases PubMed and EMBASE were used to search relevant studies. Pooled odds ratio (OR) with 95% confidence interval (CI) were estimated.ResultsA total of 120 studies were included. Atrial fibrillation and NIHSS score were common predictors for any intracerebral hemorrhage (ICH) after reperfusion therapies (both IVT and EVT), while a hyperdense artery sign (OR = 2.605, 95% CI 1.212–5.599, I2 = 0.0%) and number of thrombectomy passes (OR = 1.151, 95% CI 1.041–1.272, I2 = 54.3%) were predictors of any ICH after IVT and EVT, respectively. Common predictors for symptomatic ICH (sICH) after reperfusion therapies were age and serum glucose level. Atrial fibrillation (OR = 3.867, 95% CI 1.970–7.591, I2 = 29.1%), NIHSS score (OR = 1.082, 95% CI 1.060–1.105, I2 = 54.5%) and onset-to-treatment time (OR = 1.003, 95% CI 1.001–1.005, I2 = 0.0%) were predictors of sICH after IVT. Alberta Stroke Program Early CT score (ASPECTS) (OR = 0.686, 95% CI 0.565–0.833, I2 =77.6%) and number of thrombectomy passes (OR = 1.374, 95% CI 1.012–1.866, I2 = 86.4%) were predictors of sICH after EVT.ConclusionSeveral predictors of ICH were identified, which varied by treatment type. Studies based on larger and multi-center data sets should be prioritized to confirm the results.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=268927, identifier: CRD42021268927.

Background Current stroke guidelines recommend advanced imaging (computed tomography [CT] perfusion or magnetic resonance imaging) prior to endovascular therapy (EVT) in patients with late presentation of large vessel occlusion. Adherence to guidelines may be constrained by resources or timely access to imaging. We sought to understand the factors which influence late window imaging selection for EVT candidates with large vessel occlusion. Methods We conducted an international survey from January to May 2022. The questions aimed to identify advanced imaging and treatment decisions based on access to imaging, time delays, and simulated patient scenarios. Results There were 3000 invited participants and 1506 respondents, the majority (89.6%) from comprehensive stroke centers in high‐income countries. Neurointerventionalists comprised 31.8% and noninterventionalists 68.2% of respondents. Overall, 70.7% reported routine use of advanced imaging for late EVT selection, and 63.6% reported its usage in every case. There was greater availability of advanced imaging in comprehensive stroke centers versus primary stroke centers (67.0% versus 33.7%; P

Background Time to reperfusion is an important predictor of outcome in ischaemic stroke from large vessel occlusion (LVO). For patients requiring endovascular thrombectomy (EVT), the transfer times from peripheral hospitals in metropolitan and regional Victoria, Australia to comprehensive stroke centres (CSCs) have not been studied.Aims To determine transfer and journey times for patients with LVO stroke being transferred for consideration of EVT.Methods All patients transferred for consideration of EVT to three Victorian CSCs from January 2017 to December 2018 were included. Travel times were obtained from records matched to Ambulance Victoria and the referring centre via Victorian Stroke Telemedicine or hospital medical records. Metrics of interest included door-in-door-out time (DIDO), inbound journey time and outbound journey time.Results Data for 455 transferred patients were obtained, of which 395 (86.8%) underwent EVT. The median DIDO was 107 min (IQR 84–145) for metropolitan sites and 132 min (IQR 108–167) for regional sites. At metropolitan referring hospitals, faster DIDO was associated with use of the same ambulance crew to transport between hospitals (75 (63–90) vs 124 (99–156) min, p

Decarbonisation of heating represents a major challenge in efforts to reach Net Zero carbon emissions, especially for countries that rely heavily on the combustion of carbon-based fossil fuels to meet heating demand such as the United Kingdom. In this paper we explore the use of near surface low enthalpy geothermal energy accessed via commercial and domestic heat pump technology. These resources may become increasingly important in decarbonisation efforts but, while they are renewable, their sustainability is contingent on appropriate management. Here, we introduce a new geothermal circular heat network concept, known as a “geobattery,” which redistributes recyclable heat from emitters to users via elevated permeability pathways in the subsurface and offers a platform to manage shallow geothermal resources. If successfully implemented the concept has the potential to provide low carbon, resilient, low-cost heating that is sustainable both in terms of heat pump performance and the shallow geothermal resource. We demonstrate the concept based on the cooling requirements of a case study data centre with existing high energy use and the potential to inject the generated heat into elevated permeability pathways in the shallow subsurface. We show that thermal recharge under these conditions has the potential to arrest subsurface temperature declines associated with closely spaced borehole heat exchangers, ensure the long-term sustainability of shallow geothermal resources for generations to come, and play an important role in the decarbonisation of heating.

Background and Purpose: The short-term benefits of endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) have been widely documented, yet there is limited evidence to show that this is sustained in the long term. We aimed to determine whether the benefit of EVT on functional outcome at 3 months is maintained at 12 months and the factors correlating with functional independence and quality of life. Methods: Data for analysis came from a prospective registry of consecutive patients undergoing EVT at a single Comprehensive Stroke Center (Oct 2018–Sep 2019). A phone interview was conducted for 12-month patient outcomes. Functional outcome was assessed by the modified Rankin Scale (mRS). Quality of life was determined by return to usual place of residence, work, or driving and calculation of a health utility index using the European Quality of Life-5 Dimensions questionnaire (EQ-5D-3L). Results: Of the 151 patients who underwent EVT during the study period, 12-month follow-up was available for 145 (96%). At 12 months, 44% (n = 64) of patients were functionally independent (mRS 0–2) compared to 48% at 3 months. Mortality at 12 months was 26% compared to 17% at 3 months. Significant predictors of functional independence at 12 months were younger age and lower baseline National Institutes of Health Stroke Scale. Better quality of life significantly correlated with return to usual place of residence and driving. Conclusion: Three-month functional independence was sustained at 12 months, indicating that EVT remains beneficial for patients with AIS in the longer term.

Objectives To research and develop tools and methods for building cohorts of images linked to longitudinal healthcare records from real-world clinical images from the whole Scottish population. To provide this capability for the Scottish Medical Imaging service (provided by the Scottish National Safe Haven) to support research and AI projects. Approach Clinical images, especially when linked to routinely collected health data, are extremely useful for many types of research and AI development. However, finding and using clinical images for research data is challenging because: 1) Existing software used to search for images are designed for clinical care rather than research making it easy to find images for a particular patient. They are not designed to search for all images with particular characteristics e.g. slice thickness/scanning protocol/contrast agent/patient medication. 2) Reuse of clinical images for research requires de-identification, yet identifiable data can be present in many areas of the associated image file. Results The PICTURES (InterdisciPlInary Collaboration for efficienT and effective Use of clinical images in big data health care RESearch) 5-year programme has developed an architecture for building cohorts of images based upon research criteria and providing these in a di-identifiable form within a Safe Haven environment. There are 3 zones: • An identifiable zone which stores the raw image data and a MongoDB database which captures the metadata • A de-identified zone which provides a database and tools for cohort building which do not require imaging data expertise • Several Project Private Zones (PPZs) where researchers can install custom software and access the de-identified images for their project The architecture supports cohort building based upon features within pixel data, image metadata and linking to longitudinal health care records. Conclusion PICTURES is currently enhancing the cohort building user interface used by the National Safe Haven and supporting exemplar projects. The SMI service is live and accepting requests for more information. The software is open source and we welcome the use of the platform by other Safe Havens/research groups.

Background and PurposeCerebral venous systems play a key role in regulating stroke outcomes. We aimed to elucidate the effect of the transverse sinus (TS) filling patterns on edema expansion and neurological outcomes in patients with acute large artery occlusion (LAO).Materials and MethodsWe recruited consecutive patients with acute M1 middle cerebral artery and/or internal carotid artery occlusion who underwent pretreatment computed tomographic perfusion (CTP). On the reconstructed 4-dimensional computed tomographic angiography derived from CTP, the filling defect of the ipsilateral transverse sinus (FDITS) was defined as the length of contrast filling defect occupying at least half of the ipsilateral TS. An unfavorable outcome was defined as having a modified Rankin Scale (mRS) score of 3–6 at 3 months.ResultsA total of 318 patients were enrolled in the final analysis and 70 (22.0%) patients had baseline FDITS. The presence of FDITS was associated with the baseline NIHSS (odds ratio [OR] 1.119; 95% CI, 1.051–1.192; p < 0.001) and poor arterial collaterals (OR 3.665; 95% CI 1.730–7.766; p = 0.001). In addition, FDITS was associated with 24-h brain edema expansion (OR 7.188; 95% CI, 3.095–16.696; p < 0.001) and 3-month unfavorable outcome (OR 8.143; 95% CI 2.547–26.041; p < 0.001) independent of arterial collateral status. In the subgroup analysis of patients with FDITS who received reperfusion therapy, no significant difference was found in the rate of edema expansion and unfavorable outcome between non-reperfusion and reperfusion subgroups (both p > 0.05).ConclusionFilling defect of the ipsilateral transverse sinus was associated with edema expansion and an unfavorable outcome irrespective of the baseline arterial collateral status in patients with acute LAO, indicating that FDITS may be an important stroke-related prognostic imaging marker.

Introduction Mobile stroke units (MSUs) equipped with a CT scanner are increasingly being used to assess and treat stroke patients’ prehospital with thrombolysis and transfer them to the most appropriate hospital for ongoing stroke care and thrombectomy when indicated. The effect of MSUs in both reducing the time to reperfusion treatment and improving patient outcomes is now established. There is now an opportunity to improve the efficacy of treatment provided by the MSU. Tenecteplase is a potent plasminogen activator, which may have benefits over the standard of care stroke lytic alteplase. Specifically, in the MSU environment tenecteplase presents practical benefits since it is given as a single bolus and does not require an infusion over an hour like alteplase.Objective In this trial, we seek to investigate if tenecteplase, given to patients with acute ischaemic stroke as diagnosed on the MSU, improves the rate of early reperfusion.Methods and analysis TASTE-A is a prospective, randomised, open-label, blinded endpoint (PROBE) phase II trial of patients who had an ischaemic stroke assessed in an MSU within 4.5 hours of symptom onset. The primary endpoint is early reperfusion measured by the post-lysis volume of the CT perfusion lesion performed immediately after hospital arrival.Ethics and dissemination The study was approved by the Royal Melbourne Hospital Human Ethics committee. The findings will be published in peer-reviewed journals, presented at academic conferences and disseminated among consumer and healthcare professional audiences.Trial registration number NCT04071613.

Background: To compare the cost-effectiveness of providing endovascular thrombectomy (EVT) for patients with ischemic stroke in the >4.5 h time window between patient groups who met and did not meet the perfusion imaging trial criteria.Methods: A discrete event simulation (DES) model was developed to simulate the long-term outcome post EVT in patients meeting or not meeting the extended time window clinical trial perfusion imaging criteria at presentation, vs. medical treatment alone (including intravenous thrombolysis). The effectiveness of thrombectomy in patients meeting the landmark trial criteria (DEFUSE 3 and DAWN) was derived from a prospective cohort study of Australian patients who received EVT for ischemic stroke, between 2015 and 2019, in the extended time window (>4.5 h).Results: Endovascular thrombectomy was shown to be a cost-effective treatment for patients satisfying the clinical trial criteria in our prospective cohort [incremental cost-effectiveness ratio (ICER) of $11,608/quality-adjusted life year (QALY) for DEFUSE 3-postive or $34,416/QALY for DAWN-positive]. However, offering EVT to patients outside of clinical trial criteria was associated with reduced benefit (−1.02 QALY for DEFUSE 3; −1.43 QALY for DAWN) and higher long-term patient costs ($8,955 for DEFUSE 3; $9,271 for DAWN), thereby making it unlikely to be cost-effective in Australia.Conclusions: Treating patients not meeting the DAWN or DEFUSE 3 clinical trial criteria in the extended time window for EVT was associated with less gain in QALYs and higher cost. Caution should be exercised when considering this procedure for patients not satisfying the trial perfusion imaging criteria for EVT.

Background and Purpose: CT perfusion (CTP) has been implemented widely in regional areas of Australia for telestroke assessment. The aim of this study was to determine if, as part of telestroke assessment, CTP provided added benefit to clinical features in distinguishing between strokes and mimic and between transient ischaemic attack (TIA) and mimic.Methods: We retrospectively analysed 1,513 consecutively recruited patients referred to the Northern New South Wales Telestroke service, where CTP is performed as a part of telestroke assessment. Patients were classified based on the final diagnosis of stroke, TIA, or mimic. Multivariate regression models were used to determine factors that could be used to differentiate between stroke and mimic and between TIA and mimic.Results: There were 693 strokes, 97 TIA, and 259 mimics included in the multivariate regression models. For the stroke vs. mimic model using symptoms only, the area under the curve (AUC) on the receiver operator curve (ROC) was 0.71 (95% CI 0.67–0.75). For the stroke vs. mimic model using the absence of ischaemic lesion on CTP in addition to clinical features, the AUC was 0.90 (95% CI 0.88–0.92). The multivariate regression model for predicting mimic from TIA using symptoms produced an AUC of 0.71 (95% CI 0.65–0.76). The addition of absence of an ischaemic lesion on CTP to clinical features for the TIA vs. mimic model had an AUC of 0.78 (95% CI 0.73–0.83)Conclusions: In the telehealth setting, the absence of an ischaemic lesion on CTP adds to the diagnostic accuracy in distinguishing mimic from stroke, above that from clinical features.

In the present study we sought to measure the relative statistical value of various multimodal CT protocols at identifying treatment responsiveness in patients being considered for thrombolysis. We used a prospectively collected cohort of acute ischemic stroke patients being assessed for IV-alteplase, who had CT-perfusion (CTP) and CT-angiography (CTA) before a treatment decision. Linear regression and receiver operator characteristic curve analysis were performed to measure the prognostic value of models incorporating each imaging modality. One thousand five hundred and sixty-two sub-4.5 h ischemic stroke patients were included in this study. A model including clinical variables, alteplase treatment, and NCCT ASPECTS was weak (R2 0.067, P < 0.001, AUC 0.605) at predicting 90 day mRS. A second model, including dynamic CTA variables (collateral grade, occlusion severity) showed better predictive accuracy for patient outcome (R2 0.381, P < 0.001, AUC 0.781). A third model incorporating CTP variables showed very high predictive accuracy (R2 0.488, P < 0.001, AUC 0.899). Combining all three imaging modalities variables also showed good predictive accuracy for outcome but did not improve on the CTP model (R2 0.439, P < 0.001, AUC 0.825). CT perfusion predicts patient outcomes from alteplase therapy more accurately than models incorporating NCCT and/or CT angiography. This data has implications for artificial intelligence or machine learning models.

Introduction: A telestroke network in Northern New South Wales, Australia has been developed since 2017. We theorized that the telestroke network development would drive a progressive improvement in stroke care metrics over time.Aim: This study aimed to describe changes in acute stroke workflow metrics over time to determine whether they improved with network experience.Methods: We prospectively collected data of patients assessed by telestroke who received multimodal computed tomography (mCT) and were diagnosed with ischemic stroke or transient ischemic attack from January 2017 to July 2019. The period was divided into two phases (phase 1: January 2017 – October 2018 and phase 2: November 2018 – July 2019). We compared median door-to-call, door-to-image, and door-to-decision time between the two phases.Results: We included 433 patients (243 in phase 1 and 190 in phase 2). Each spoke site treated 1.5–5.2 patients per month. There were Door-to-call time (median 39 in phase 1, 35 min in phase 2, p = 0.18), and door-to-decision time (median 81.5 vs. 83 min, p = 0.31) were not improved significantly. Similarly, in the reperfusion therapy subgroup, door-to-call time (median 29 vs. 24.5 min, p = 0.12) and door-to-decision time (median 70.5 vs. 67.5 min, p = 0.75) remained substantially unchanged. Regression analysis showed no association between time in the network and door-to-decision time (coefficient 1.5, p = 0.32).Conclusion: In our telestroke network, acute stroke timing metrics did not improve over time. There is the need for targeted education and training focusing on both stroke reperfusion competencies and the technical aspects of telestroke in areas with limited workforce and high turnover.

Background and Purpose: Previous studies showed that acute reocclusion after endovascular therapy is related to residual stenosis. However, we observed that reperfusion status but not residual stenosis severity is related to acute reocclusion. This study aimed to assess which factor mention above is more likely to be associated with artery reocclusion after endovascular treatment. Methods: This study included 86 acute ischemic stroke patients who had middle cerebral artery (MCA) atherosclerotic occlusions and received endovascular treatment within 24 h of a stroke. The primary outcomes included intraprocedural reocclusion assessed during endovascular treatment and delayed reocclusion assessed through follow-up angiography. Results: Of the 86 patients, the intraprocedural reocclusion rate was 7.0% (6/86) and the delayed reocclusion rate was 2.3% (2/86). Regarding intraprocedural occlusion, for patients with severe residual stenosis, patients with successful thrombectomy reperfusion showed a significantly lower rate than unsuccessful thrombectomy reperfusion (0/30 vs. 6/31, p = 0.003); on the other hand, for patients with successful thrombectomy reperfusion, patients with severe residual stenosis showed no difference from those with mild to moderate residual stenosis in terms of intraprocedural occlusion (0/30 vs. 0/25, p = 1.00). In addition, after endovascular treatment, all patients achieved successful reperfusion. There was no significant difference in the delayed reocclusion rate between patients with severe residual stenosis and those with mild to moderate residual stenosis (2/25 vs. 0/61, p = 0.085). Conclusion: Reperfusion status rather than residual stenosis severity is associated with artery reocclusion after endovascular treatment. Once successful reperfusion was achieved, the reocclusion occurrence was fairly low in MCA atherosclerosis stroke patients, even with severe residual stenosis.

Background: Cardioembolic strokes are common however atrial fibrillation, the most common cause, is often asymptomatic and difficult to detect. There is evidence that infarct topography and volume on magnetic resonance imaging may be associated with specific stroke etiologies.Aim: A systematic review and meta-analysis were undertaken to summarize the available evidence on the association between stroke etiology, infarct topography, and volume.Methods: A systematic review was conducted using Medline (OVID), Embase (OVID), and PubMed databases. Hand searches of the gray literature and of reference lists in relevant articles were also performed. A quality assessment was undertaken, based on the STROBE checklist. For each study, the number of patients with and without a CE source of stroke and infarct topography was collected and outcomes presented as odds ratios (OR) with 95% CI and p-values.Results: Four thousand eight hundred and seventy-three patients with ischemic stroke were included, of whom 1,559 were determined to have a CE source. Bilateral infarcts (OR 3.41; 95% CI 2.20–5.29; p < 0.0001) and multiple territory infarcts (OR 1.57; 95% CI 1.12–2.21; p = 0.009) were more common in patients with a CE source of stroke, than patients without a CE source. Lacunar infarcts (OR 0.49; 95% CI 0.31–0.80; p = 0.004) were more likely to occur in patients without a CE source. No significant difference between the frequency of multiple infarcts (OR 0.96; 95% CI 0.57–1.61; p = 0.87) anterior circulation (OR 1.45; 95% CI 0.83–2.53; p = 0.19) or posterior circulation infarcts (OR 1.06; 95% CI 0.72–1.57; p = 0.75), between the two groups were identified. Three out of four studies examining volume, found a significant association between increased infarct volume and CE source of stroke. A sensitivity analysis with cryptogenic and undetermined stroke sources assumed to be cardioembolic, did not alter the associations observed.Conclusion: The findings of this systematic review and meta-analysis are broadly consistent with previous literature and provide more robust evidence on the association between infarct topography, volume and stroke etiology. Our findings may assist with refining cardiac investigations for patients with cryptogenic stroke, based on infarct topography.

Background and Aims: Disability-adjusted life years (DALYs) are an important measure of the global burden of disease that informs patient outcomes and policy decision-making. Our study aimed to compare the DALYs saved by endovascular thrombectomy (EVT) in the Australasian-based EXTEND-IA trial vs. clinical registry data from EVT in Australian routine clinical practice.Methods: The 3-month modified Rankin scale (mRS) outcome and treatment status of consecutively enrolled Australian patients with large vessel occlusion (LVO) stroke were taken from the International Stroke Perfusion Imaging Registry (INSPIRE). DALYs were calculated as the summation of years of life lost (YLL) due to premature death and years lived with a disability (YLD). A generalized linear model (GLM) with gamma family and log link was used to compare the difference in DALYs for patients receiving/not receiving EVT while controlling for key covariates. Ordered logit regression model was utilized to compare the difference in functional outcome at 3 months between the treatment groups. Cox regression analysis was undertaken to compare the difference in survival over an 18-year time horizon. Estimated long-term DALYs saved based on the EXTEND-IA randomized controlled trial (RCT) results were used as the comparator.Results: INSPIRE patients who received EVT treatment only achieved nominally better functional outcomes than the non-EVT group (p = 0.181) at 3 months. There was no significant survival gain from EVT over the first 3 months of stroke in both INSPIRE and EXTEND-IA patients. However, measured against no EVT in the long-term, EVT in INSPIRE was associated with no significant survival gain [hazard ratio (HR): 0.92, 95% confidence interval (CI): 0.78–1.08, p = 0.287] compared with the survival benefit extrapolated from the EXTEND-IA trial (HR: 0.42, 95% CI: 0.22–0.82, p = 0.01]. Offering EVT to patients with LVO stroke was also associated with fewer DALYs lost (11.04, 95% CI: 10.45–11.62) than those not receiving EVT in INSPIRE (12.13, 95% CI: 11.75–12.51), a reduction of −1.09 DALY (95% CI: −1.76 to −0.43, p = 0.002). The absolute magnitude of the treatment effect was lower than that seen in EXTEND-IA (−2.72 DALY reduction in EVT vs non-EVT patients).Conclusions: EVT for the treatment of LVO in a registry of routine care was associated with significantly lower DALYs lost than medical care alone, but the saved DALYs are less than those reported in clinical trials, as there were major differences in the baseline characteristics of the patients.

Background and purpose: Midline shift is a life-threatening complication of acute large artery occlusion (LAO). The value of superficial middle cerebral vein (SMCV) for predicting midline shift is currently unclear for patients with acute LAO.Methods: Consecutive acute LAO (middle cerebral artery M1 ± intracranial internal carotid artery) patients between March 2018 and May 2019 were included. Absent filling of ipsilateral cortical vein (marked as SMCV–) was defined as no contrast filling into the vein across the whole venous phase of four-dimensional computed tomography (CT) angiography derived from CT perfusion in the ischemic hemisphere.Results: In the total of 81 patients, 31 (38.4%) were identified as SMCV–. SMCV– independently predicted midline shift, with sensitivity of 87.5% and specificity of 82.5%. Receiver operating characteristic analysis showed that including SMCV– as a predictor in addition to baseline ischemic core volume significantly increased the area under the curve in predicting midline shift (SMCV– with baseline ischemic core volume vs. baseline ischemic core volume: AUC = 0.903 vs. 0.841, Z = 2.451, P = 0.014).Conclusion: In acute LAO patients, the presence of SMCV– was a sensitive and specific imaging marker for midline shift. SMCV– had supplementary value to baseline ischemic core volume in predicting midline shift.

Concerns about secondary use of data and limited opportunities for benefit-sharing have focused attention on the tension that Indigenous communities feel between (1) protecting Indigenous rights and interests in Indigenous data (including traditional knowledges) and (2) supporting open data, machine learning, broad data sharing, and big data initiatives. The International Indigenous Data Sovereignty Interest Group (within the Research Data Alliance) is a network of nation-state based Indigenous data sovereignty networks and individuals that developed the ‘CARE Principles for Indigenous Data Governance’ (Collective Benefit, Authority to Control, Responsibility, and Ethics) in consultation with Indigenous Peoples, scholars, non-profit organizations, and governments. The CARE Principles are people– and purpose-oriented, reflecting the crucial role of data in advancing innovation, governance, and self-determination among Indigenous Peoples. The Principles complement the existing data-centric approach represented in the ‘FAIR Guiding Principles for scientific data management and stewardship’ (Findable, Accessible, Interoperable, Reusable). The CARE Principles build upon earlier work by the Te Mana Raraunga Maori Data Sovereignty Network, US Indigenous Data Sovereignty Network, Maiam nayri Wingara Aboriginal and Torres Strait Islander Data Sovereignty Collective, and numerous Indigenous Peoples, nations, and communities. The goal is that stewards and other users of Indigenous data will ‘Be FAIR and CARE.’ In this first formal publication of the CARE Principles, we articulate their rationale, describe their relation to the FAIR Principles, and present examples of their application.

Background: Admission outside normal business hours has been associated with prolonged door-to-treatment times and poorer patient outcomes, the so called “weekend effect. ” This is the first examination of the weekend effect in a telestroke service that uses multi-modal computed tomography.Aims: To examine differences in workflow and triage between in-hours and out-of-hours calls to a telestroke service.Methods: All patients assessed using the Northern New South Wales (N-NSW) telestroke service from April 2013 to January 2019 were eligible for inclusion (674 in total; 539 with complete data). The primary outcomes measured were differences between in-hours and out-of-hours in door-to-call-to-decision-to-needle times, differences in the proportion of patients confirmed to have strokes or of patients selected for reperfusion therapies or patients with a modified Rankin Score (mRS ≤ 2) at 90 days.Results: There were no significant differences between in-hours and out-of-hours in any of the measured times, nor in the proportions of patients confirmed to have strokes (67.6 and 69.6%, respectively, p = 0.93); selected for reperfusion therapies (22.7 and 22.6%, respectively, p = 0.56); or independent at 3 months (34.8 and 33.6%, respectively, p = 0.770). There were significant differences in times between individual hospitals, and patient presentation more than 4.5 h after symptom onset was associated with slower times (21 minute delay in door-to-call, p = 0.002 and 22 min delay in door-to-image, p = 0.001).Conclusions: The weekend effect is not evident in the Northern NSW telestroke network experience, though this study did identify some opportunities for improvement in the delivery of acute stroke therapies.

Stroke is the second most common cause of death and remains a persistent health challenge globally. Due to its highly time-sensitive nature, earlier stroke treatments should be enforced for improved patient outcome. The mobile stroke unit (MSU) was conceptualized and implemented to deliver the diagnosis and treatment to a stroke patient in the ultra-early time window (

Background: Mobile stroke units (MSU) have been proposed to expedite delivery of recombinant tissue plasminogen activator (tPA) and expedite endovascular clot retrieval (ECR). Unexplored questions in the use of MSU include: maximal distance from base, time limit with regards to the use CT imaging, CT Angiography, CT Perfusion, and Telemedicine. We developed a computational model as an app (https://gntem3.shinyapps.io/ambmc/), taking into account traveling time to explore this issue. The aim of this study was to define the operating parameters for an MSU in a large metropolitan city, based on the geography of Melbourne.Methods: There are 2 hospitals (Royal Melbourne Hospital/RMH, Monash Medical Center/MMC) designated to provide state-wide ECR services. In these spatial simulations, the MSU is based at RMH and delivers tPA at the patient's pick-up address and then takes the patient to the nearest ECR center. We extracted the geocode of suburbs in Melbourne and travel time to each hospital using ggmap, an interface to Google Map API. The app contains widgets for varying the processing time at the patient location (default = 30 min), performing CT angiography (default = 10 min), performing telemedicine consultation (default = 15 min). The data were compared against those for usual ambulance metrics (default traveling time = 15 min, processing time at patient's location = 20 min, door to tPA = 60 min, door to groin = 90 min). Varying the widgets allow the viewer to explore the trade-off between the variable of interest and time to therapy at a suburb level.Results: The MSU was superior for delivering tPA to all Melbourne suburbs (up to 76 min from RMH). If the CTA times or processing time at location increased by 20 min then it was superior for providing ECR to only 74.9% of suburbs if the return base was RMH. Addition of CT Perfusion or telemedicine consultation affect the ability of a single hospital to provide ECR but not tPA if these additions can be limited to 20 min. Conclusion: The app can help to define how best to deploy the MSU across Melbourne. This app can be modified and used to optimize operating characteristics of MSU in other centers around the world.