Abstract 1122‐000126: Mobile Stroke Unit Process Metrics in Large Vessel Occlusion Stroke Patients: BEST‐MSU Substudy

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Alexandra L Czap ◽  
Anne W Alexandrov ◽  
May Nour ◽  
Noopur Singh ◽  
Mengxi Wang ◽  
...  
Keyword(s):  
Stroke Unit ◽  
Large Vessel ◽  
Categorical Variables ◽  
Continuous Variables ◽  
Stroke Patients ◽  
Vessel Occlusion ◽  
Stroke Treatment ◽  
Symptomatic Intracerebral Hemorrhage ◽  
Mobile Stroke Unit ◽  
Process Metrics

Introduction : Mobile Stroke Units (MSUs) speed thrombolytic treatment for acute ischemic stroke and improve clinical outcomes compared to standard management by Emergency Medical Services (EMS). However, MSU process metrics in the subset of patients with large vessel occlusions (LVOs) having endovascular thrombectomy (EVT) have yet to be optimized. Methods : A pre‐specified Benefits of Stroke Treatment Using a Mobile Stroke Unit (BEST‐MSU) substudy of tPA‐eligible stroke patients with imaging evident LVOs was conducted. The primary outcome was process metrics related to treatment times from stroke onset and first medical alert. Safety outcomes included rates of symptomatic intracerebral hemorrhage and procedural complications. Groups were compared using Chi‐square or Fisher’s exact tests for categorical variables, and Wilcoxon rank‐sum tests for continuous variables. Results : A total of 295 patients were included, 169 in the MSU group and 126 in the EMS group. Baseline characteristics were comparable between the groups, with the exception of baseline NIHSS (MSU mean 19.0 [IQR 13.0,23.0] vs EMS 16.0 [11.0, 20.0], p = 0.003). 92% of MSU and 87% of EMS LVO patients received tPA, and 78% and 85% went on to have EVT. Process metrics are detailed in Table 1. MSU LVO patients had faster tPA bolus from 911‐alert (MSU 45.0 minutes [40.0, 53.5] vs EMS 76.0 [64.0, 87.8], p<0.001), however the two groups had similar alert to groin puncture (MSU 142.5 [116.8, 171.0] versus EMS 131.5 [114.0, 159.8], p = 0.15). MSU patients spent more time on‐scene, (EMS arrival to ED arrival, 53.0 [45.0, 62.0] vs 27.0 [22.0, 33.0], p<0.001) however less time prior to EVT (door to groin puncture, 76.5 [54.8, 108.5] vs 94.0 [72.0, 123.0], p<0.001) with variable use of field CTAs and direct cath lab admission with ED bypass, yielding a net neutral result. The variability among site protocols is reflected in the range of median alert to groin puncture times (minimum 107.0 minutes, maximum 152.0). In the 222 patients undergoing EVT, median alert to recanalization time was 181.5 minutes [146.8, 225.5] in the MSU group and 190.5 [157.5, 227.5] in the EMS group (p = 0.47). Recanalization (Thrombolysis In Cerebral Infarction [TICI] 2b/3) was achieved in 76% of MSU and 70% of EMS (p = 0.32) with comparable rates of EVT complications (including hemorrhage, perforation, dissection, hematoma). 54% MSU and 44% of EMS LVO patients achieved good functional outcome (modified Rankin Scale [mRS] ≤ 2) at 90 days (p = 0.11). Conclusions : In tPA‐eligible LVO stroke patients, MSU management did not increase or expedite EVT treatment times as compared to standard EMS management. Future MSU processes should include field CTA with direct admission to cath labs to maximize the early treatment advantage this technology provides.

Abstract WMP12: Does IV tPA Improve Outcomes in Stroke Patients with Large Vessel Occlusions Treated with Intra-arterial Therapy?

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Joseph T Ho ◽  
Jason W Tarpley ◽  
Hsin-Fang Li
Keyword(s):  
Ischemic Stroke ◽  
Length Of Stay ◽  
Time Frame ◽  
Large Vessel ◽  
Categorical Variables ◽  
Complication Rates ◽  
Continuous Variables ◽  
Stroke Patients ◽  
Vessel Occlusion ◽  
Iv Tpa

Introduction: The benefit of endovascular therapy (IAT) for the treatment of emergent large vessel occlusion (ELVO) in stroke patients has been established. However, it is not known whether administration of IV tPA prior to IAT is beneficial in these patients. Methods: A retrospective review of ischemic stroke patients in the Providence Health & Services Get with the Guidelines (GWTG) database was performed from 01/2012 to 05/2016. The analysis was limited to patients who presented within 4.5 hours of last known well time (LKWT) and treatment included any form of IAT. End points were limited to data available in the GWTG database, including discharge mRS, discharge NIHSS, change in NIHSS from admission to discharge, and length of stay. Continuous variables were summarized using means and standard deviation while categorical variables were summarized using frequencies and percentages. To yield a more robust estimate against outliers for the time-related variables, medians and interquartile range (IQR) were computed and assessed using Wilcoxon rank sum tests. Chi-square tests and independent two-sample t-tests were used to evaluate the demographic and outcome differences for categorical and continuous variables, respectively. Results: A total of 10,868 patients with an ischemic stroke diagnosis were found in the specified time frame and presented within 4.5 hours of LKWT. Of these, 461 patients were treated with some form of IAT, 235 received IV tPA prior to IAT, 226 had IAT alone due to contraindication to IV tPA. There was no statistical difference in patient demographics, complication rates, TICI score, discharge NIHSS or mRS at discharge. There was a significantly higher NIHSS on admission (18.3 vs 16.7, p = 0.026), greater improvement in NIHSS (11.6 vs. 7.9, p=0.012), longer door to IAT (146 vs 101.5 min, p < 0.0001), and shorter length of stay (5 vs 6 days, p = 0.016) in the IV tPA group. Conclusions: These data suggest that IV tPA, when administered to eligible patients with ELVO, provided some benefit over IAT alone, even though it delayed IAT. Future prospective randomized trials are planned that may better address this question, but these results underscore the need for retrospective analysis of existing data.

Abstract WP76: Artificial Intelligence CTA Vessel Density Mapping to Enhance Identification of Large Vessel Occlusions in Mobile Stroke Unit

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Kevin Brown ◽  
Bryan Villareal ◽  
Kenneth Harrell ◽  
Mersedeh Bahr Hosseini ◽  
Lucas Restrepo-Jimenez ◽  
...  
Keyword(s):  
Stroke Unit ◽  
Clinical Decision Making ◽  
Vessel Density ◽  
Large Vessel ◽  
Stroke Patients ◽  
Anterior Circulation ◽  
Vessel Occlusion ◽  
Stroke Units ◽  
Density Mapping ◽  
Mobile Stroke Unit

Background: Equipped with CT scanners capable of imaging the brain parenchyma and vasculature, Mobile Stroke Units (MSU) have the ability to image, diagnose and treat stroke patients in the prehospital setting. Automated CTA vessel density mapping could enhance frontline neurologist scan review in identifying large vessel occlusion (LVO), ensuring appropriate patient diagnosis and routing. Methods: We analyzed consecutive acute ischemic stroke patients undergoing CTA imaging in a regional Mobile Stroke Unit. Automated CTA vessel density mapping was performed in the field immediately after scan completion. CTA source images were wirelessly transferred to an off-site processing server (RAPID.Ai, IschemiaView) for artery reconstruction and color-coded density mapping, with blue, green, yellow, and red color shading indicating vessel density decreases of 70%-85%, 60%-75%, 45%-60%, and <45%. Results: Among all 16 patients, median processing time was 186 secs, and all images were available in time to aid clinical decision-making. Overall, automated processing yielded evaluable images in 94% (suboptimal contrast opacification precluded analysis of 1). Of the 15 diagnostically adequate exams, 100% (15/15) showed concordance for identification of anterior circulation occluded/abnormal vessel territories between automated CTA vessel density mapping and expert physician final CTA interpretation. Cases included true positives in 7, and true negatives in 8. Among true positives, CTA vessel density mapping identified the symptomatic occlusion in 6/6 and also correctly identified a severe cervical ICA stenosis unrelated to the clinical presentation in 1/1. Correctly detected intracranial occlusions included: ICA-17%. M1-17%, M1-M2 junction-17%, and M2-50%. Degree of vessel density diminution correlated with proximal-distal occlusion location. Conclusion: CTA vessel density mapping can feasibly and efficiently be conducted in Mobile Stroke Units and shows high accuracy in detection of large and medium intracranial vessel occlusions. Extension of mapping to the intracranial posterior circulation and algorithmic adjustment for proximal cervical stenoses/occlusions would further improve utility in aiding prehospital routing.

scholarly journals Air-Mobile Stroke Unit for access to stroke treatment in rural regions

2018 ◽  
Vol 13 (6) ◽  
pp. 568-575 ◽  
Author(s):  
Silke Walter ◽  
Henry Zhao ◽  
Damien Easton ◽  
Cees Bil ◽  
Jonas Sauer ◽  
...  
Keyword(s):  
Rural Areas ◽  
Stroke Unit ◽  
Systems Of Care ◽  
Intravenous Thrombolysis ◽  
Rural And Remote ◽  
Stroke Patients ◽  
Stroke Treatment ◽  
Remote Areas ◽  
Mobile Stroke Unit ◽  
Rural And Remote Areas

Background In recent years, important progress has been made in effective stroke treatment, however, patients living in rural and remote areas have nil or very limited access to timely reperfusion therapies. Aims Novel systems of care to overcome the detrimental treatment gap for stroke patients living in rural and remote regions need to be developed. Summary of review A possible solution to the treatment disparity between stroke patients living in metropolitan and rural areas may involve the use of specially designed aircrafts equipped with the ability to diagnose and treat acute stroke at remote emergency sites. We describe technical solutions for an Air-Mobile Stroke Unit (Air-MSU) concept, where an aircraft is customized with the ability to perform multimodal computed tomography, in addition to onboard laboratory equipment and telemedicine connection. The Air-MSU is envisioned not only to allow intravenous thrombolysis in the field but also to allow prehospital triage to a comprehensive stroke center through use of contrast intracerebral vascular imaging. Several options for the Air-MSU approach are described, and issues regarding the potential medical benefit, optimal operating environment, technical realization, and integration in pre-existing solutions (e.g., flying doctor service) are addressed. Conclusion The Air-MSU may represent a novel tool to reduce treatment disparity for stroke patients in rural and remote areas. However, this approach requires further implementation research to determine the overall benefit to these communities.

Abstract 3130: A 101 cm 3 Diffusion-Weighted Imaging (DWI) Cerebral Infarct Volume is the Maximum Volume Compatible with Good 30- Day Functional Outcome

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Esteban Cheng-Ching ◽  
Junya Aoki ◽  
Yohei Tateishi ◽  
Dolora Wisco ◽  
Gabor Toth ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Functional Outcome ◽  
Diffusion Weighted Imaging ◽  
Infarct Volume ◽  
Cerebral Infarct ◽  
Large Vessel ◽  
Large Vessel Occlusion ◽  
Stroke Patients ◽  
Vessel Occlusion ◽  
Stroke Treatment

Background: Several predictors of clinical outcome have been identified in acute ischemic stroke patients, including age, National Institutes of Health Stroke Scale scores (NIHSS), and large vessel occlusion. Predicted infarct volumes are thought to generally correlate with clinical outcome, however, to date, mostly small studies have failed to demonstrate a convincing relationship between Diffusion-weighted imaging (DWI) volumes and clinical outcome, and this correlation is controversial. Hypothesis: We hypothesized that final DWI infarction volumes would correlate with 30-day modified Rankin Score (mRS). We also sought to describe the maximum cerebral infarct volume compatible with a favorable 30 day (mRS of 0-2) outcome. Methods: We retrospectively reviewed a prospectively collected database of acute stroke patients with large vessel occlusion who were potential intra-arterial therapy candidate, which recently incorporated systematically collected imaging data at our large academic medical center. Additional inclusion criteria were MRI on admission as per our hyperacute stroke treatment protocol, and available 30-day mRS (n=91). Final DWI volume was obtained from the last MRI the patient had during their stroke treatment admission. Differences between final DWI volume and 30-day mRS were analyzed using the Kruskal-Wallis test. Results: See Table 1 for DWI volumes by individual mRS. There was a strong overall positive relationship between final DWI volume and 30-day mRS [Kruskall Wallis p= .0047]. No patient with an mRS of 0 had a DWI volume >12.1 cm 3 . No patients with an mRS of ≤1 had an DWI volume over 85 cm 3 , and no patient with a mRS of ≤2 had a DWI volume over 101 cm 3 . Conclusions: Cerebral infarct volumes strongly correlate with 30-day functional outcome, but there is great individual variability. The maximum infarct volume compatible with survival and mild or less disability at 30 days was 101 cm 3 . In this study, the maximum cerebral infarct volume compatible with zero clinical symptoms or disability at 30 days was 12.1 cm 3 .

scholarly journals First Automated Stroke Imaging Evaluation via Electronic Alberta Stroke Program Early CT Score in a Mobile Stroke Unit

2016 ◽  
Vol 42 (5-6) ◽  
pp. 332-338 ◽  
Author(s):  
Iris Quasar Grunwald ◽  
Andreas Ragoschke-Schumm ◽  
Michael Kettner ◽  
Lenka Schwindling ◽  
Safwan Roumia ◽  
...  
Keyword(s):  
Stroke Unit ◽  
Stroke Management ◽  
Imaging Evaluation ◽  
Vessel Occlusion ◽  
Stroke Treatment ◽  
Stroke Imaging ◽  
Mobile Stroke Unit ◽  
Potential Benefits ◽  
Comprehensive Stroke Center ◽  
Stroke Center

Background: Recently, a mobile stroke unit (MSU) was shown to facilitate acute stroke treatment directly at the emergency site. The neuroradiological expertise of the MSU is improved by its ability to detect early ischemic damage via automatic electronic (e) evaluation of CT scans using a novel software program that calculates the electronic Alberta Stroke Program Early CT Score (e-ASPECTS). Methods: The feasibility of integrating e-ASPECTS into an ambulance was examined, and the clinical integration and utility of the software in 15 consecutive cases evaluated. Results: Implementation of e-ASPECTS onto the MSU and into the prehospital stroke management was feasible. The values of e-ASPECTS matched with the results of conventional neuroradiologic analysis by the MSU team. The potential benefits of e-ASPECTS were illustrated by three cases. In case 1, excluding early infarct signs supported the decision to directly perform prehospital thrombolysis. In case 2, in which stroke was caused by large-vessel occlusion, the high e-ASPECTS value supported the decision to initiate intra-arterial treatment and triage the patient to a comprehensive stroke center. In case 3, the e-ASPECTS value was 10, indicating the absence of early infarct signs despite pre-existing cerebral microangiopathy and macroangiopathy, a finding indicating the program's robustness against artefacts. Conclusions: This study on the integration of e-ASPECTS into the prehospital stroke management via a MSU showed for the first time that such integration is feasible, and aids both decision regarding the treatment option and the triage regarding the most appropriate target hospital.

010 The melbourne mobile stroke unit substantially improves thrombolysis times and pre-hospital triage

2018 ◽  
Vol 89 (6) ◽  
pp. A5.2-A5
Author(s):  
Henry Zhao ◽  
Skye Coote ◽  
Lauren Pesavento ◽  
Francesca Langenberg ◽  
Patricia Desmond ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Stroke Unit ◽  
Life Support ◽  
Hospital Treatment ◽  
Future Research ◽  
Stroke Patients ◽  
Time Saving ◽  
Royal Melbourne Hospital ◽  
Stroke Treatment ◽  
Mobile Stroke Unit

IntroductionThe Melbourne mobile stroke unit (MSU) project is the first Australian pre-hospital stroke service that delivers on-scene imaging, treatment and triage. The MSU vehicle consists of a Mercedes Sprinter-5 chassis with on-board CereTom 8-slice portable CT scanner and telemedicine capabilities. On-board crew consists of a neurologist/telemedicine, nurse, radiographer and two paramedics (advanced-life-support and mobile-intensive-care). The MSU service is co-dispatched within 20 km of Royal Melbourne Hospital. We describe the service activity since project launch.MethodsData are sourced from the Melbourne MSU registry, an ongoing prospectively collected database of all MSU dispatched cases since November 2017.ResultsIn the first 50 operational days, there were a total of n=255 dispatches (5.1/day), of which 47% of patients received on-scene attendance. On-scene CT was performed on 52% of all attendances. Of n=29 suspected ischaemic stroke cases<6 hours of symptom onset (24% of attended), n=10 (34%) received pre-hospital thrombolysis and n=6 (21%) were directed for endovascular thrombectomy. 30% of patients were thrombolysed within 90 min of symptom onset. A total of n=7 (14% of all stroke) patients were recommended to bypass the closest hospital to a specialist centre for endovascular, neurosurgical or other services. The median scene-to-thrombolysis time of 36.5 min was substantially better than Australian in-hospital averages and represented an estimated 30–45 min time saving compared to in-hospital treatment.DiscussionThe Melbourne MSU project shows that pre-hospital diagnosis and treatment of stroke patients is feasible and associated with substantial time saving in providing acute stroke treatment and triage. Future research will focus on optimising MSU dispatch and cost-effectiveness analysis.

Abstract 1122‐000154: Effect of Intravenous Thrombolysis on Early Clot Lysis in Large Vessel Occlusion Strokes Undergoing Thrombectomy

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Mohamed Shehabeldin ◽  
Brendan Eby ◽  
Adam N Wallace ◽  
Amber Salter ◽  
Arindam R Chatterjee ◽  
...  
Keyword(s):  
Intravenous Thrombolysis ◽  
Standard Of Care ◽  
Large Vessel ◽  
Categorical Variables ◽  
Clot Lysis ◽  
Continuous Variables ◽  
Large Vessel Occlusion ◽  
Vessel Occlusion ◽  
Angiography Suite ◽  
Significant Difference

Introduction : Intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT) are both standard of care treatments for acute ischemic stroke patients with large vessel occlusion (LVO) who are eligible for one or both treatments. IVT may result in early recanalization in some patients with LVO. The objective of this study is to analyze whether IVT influences pre‐thrombectomy clot lysis in LVO acute ischemic strokes. Methods : We reviewed prospectively collected data for all patients with LVO ischemic strokes who were transferred to the angiography suite with intention to perform EVT at a single comprehensive stroke center between January 2016 to December 2018. We identified subjects who showed partial or complete clot lysis vs no lysis based on the first angiographic picture of the occluded territory at the time of the initial vessel selection. Descriptive statistics were used to summarize demographic and clinical characteristics. We compared key predictor variables between lysis and no lysis groups including baseline variables, effect of IVT, time from IVT to groin puncture, LVO location, final modified treatment in cerebral ischemia (mTICI) score and discharge Modified Rankin Scale (mRS). t‐test or Kruskal‐Wallis test for continuous variables and chi square test or Fisher’s Exact test for categorical variables. Results : Two hundred and fifty‐nine patients were included. Among these patients, 10.8% (28/259) showed partial or complete lysis of the clot vs 89.2% (231/259) with no lysis. Among these patients who showed clot lysis, 16/28 (57.1%) received IVT. The use of IVT did not show differences between both groups (p = 0.18). There were no differences in the baseline characteristics except for gender, which was the only variable significantly associated with clot lysis. Men had 2‐fold higher odds of spontaneous lysis compared to females (OR [95%CI]: 2.39 [1.01, 5.65], p = 0.04). There was significant difference in the final mTICI between both groups (p <0.001). Conclusions : Our study showed that IVT in a modern practice was not associated with pre‐thrombectomy lysis. Some patients had pre‐thrombectomy lysis despite not receiving IVT.

Abstract TP28: Defining Large Vessel and Routing Criteria for Endovascular Patients

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Coleman Martin ◽  
Angela Hawkins ◽  
Karin Olds ◽  
Naveed Akhtar ◽  
William Holloway
Keyword(s):  
Systems Of Care ◽  
Intravenous Thrombolysis ◽  
Heart Association ◽  
Large Vessel ◽  
Complication Rates ◽  
Stroke Work ◽  
Stroke Patients ◽  
Vessel Occlusion ◽  
Stroke Treatment ◽  
Large Vessel Stroke

Background: Five recently published randomized trials of endovascular therapy versus medical management, including intravenous thrombolysis, demonstrated strong positive data in support endovascular thrombectomy procedures. The American Heart Association/American Stroke Association released a focused update to specifically incorporate the findings of these trials. Implementing the care these studies show as beneficial requires a mechanism to rapidly transfer large vessel occlusion patients from primary stroke centers to those offering thrombectomy. Purpose: The purpose of the project was to streamline stroke work-up across the various levels of stroke hospitals and to apply rapid routing practices when transferring stroke patients between facilities. We evaluated the changes in stroke systems of care, with an emphasis on the role of pre-hospital stroke triage, inter-hospital transfer, and the two main levels of stroke center certification (primary and comprehensive). Methods: The system stroke steering team, defined four primary processes to reduce transfer times. These included 1) benchmarks for hospital door in to door out times of transferring centers 2) scripted transfer verbiage to designated time critical patients 3) large vessel stroke criteria definitions 4) pre-notification of the endovascular team to treat potential patients presenting with stroke. A reduction in time between initial patient contact and arterial puncture times and measures of patient outcomes were used as indicators of effectiveness. Results: The implementation of four process improvements for large vessel stroke patients was associated with improved treatment times. Mean door to recanalization times decreased from 224 minutes in 2014 to 112 minutes, thus far in 2016. Stroke treatment rates for tPA increased from 19.8% in 2013 to 22.7% in 2016, and endovascular treatment rates of 14.6% to 18.1% in the same time period. Conversely, complication rates from stroke treatment declined within the same period from 7.4% to 3.8%. Conclusion: Within a metropolitan health system, using the above multimodal approach to streamline the transfer of patients from primary to comprehensive centers decreases latency to treatment and is associated with improved outcomes.

scholarly journals Rapid Identification of Large Vessel Occlusion Stroke Subtype in the PreHospital Setting

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Daniel Torolira, B.S. ◽  
Sara Brown, M.D. ◽  
Fen-Lei Chang, M.D.
Keyword(s):  
Medical Center ◽  
Accurate Determination ◽  
Hospital Setting ◽  
Large Vessel ◽  
Large Vessel Occlusion ◽  
Stroke Patients ◽  
Accurate Identification ◽  
Vessel Occlusion ◽  
Stroke Treatment ◽  
Stroke Subtypes

Background and Hypothesis: Stroke treatment is highly time-sensitive, with an estimated 1.9 million neurons dying per minute during an untreated ischemic stroke. The recent advent of mechanical thrombectomy (MT) and its illustrated safety and efficacy in treating large vessel occlusion (LVO) strokes has generated a need to rapidly identify LVO patients who may otherwise be brought to the nearest hospital, which may not have the capability to perform the procedure. Accurate identification of LVO in the pre-hospital setting would allow immediate EMS transport to an MTcapable Comprehensive Stroke Center, thus reducing time-to-treatment and improving patient outcome. While various grading scales, such as the C-STAT, have been developed for this purpose, all have shown to lack sensitivity and specificity for accurate LVO determination. We hypothesize that a new scale combining common LVO presentations as positive values and those of other stroke subtypes, such as small vessel occlusion (SVO) and cardioembolic stroke (CE), as negative values will increase the accuracy of LVO determination. Methods: This is a retrospective chart review analysis of 86 patients evaluated for stroke between January 2017-May 2018 at the Parkview Regional Medical Center with imaging confirmed LVO, SVO or CE diagnoses.   Results: C-STAT stroke scale had a sensitivity of 54.5% and a specificity of 86.7% in differentiating LVO from other stroke subtypes. Compared to C-STAT, our new model showed a significantly higher sensitivity of 81.8% (p=0.0038) and a nonsignificant decreased specificity of 75.0% (p=0.061).  Conclusion: Our findings suggest that our new scale combining common clinical presentations in LVO stroke patients as positive predictor values and those in SVO and CE stroke patients as negative predictor values may allow for a more accurate determination of LVO stroke in the pre-hospital setting without significant delay. A prospective, larger patient cohort in a pre-hospital setting is needed to validate these findings.

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