bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP83: Identification Of Intracranial Atherosclerosis-related Acute Middle Cerebral Artery Occlusion On Computed Tomography Perfusion
Authors: Wang Zigao , Cao Wenjie
Published: February 2023

Objective:
To explore whether baseline computed tomography perfusion (CTP) can be used to identify intracranial atherosclerotic stenosis (ICAS) as the etiology of middle cerebral artery occlusion (MCAO) in acute ischemic stroke patients.

Methods:
We retrospectively analyzed the clinical and CTP data of consecutive patients with acute MCAO between Jan 2017 and May 2022 in our hospital. CTP characteristics was reprocessed using MIStar, including the core volume, the penumbra volume, the location of the major core. The maximal diameter of the major core was manually measured on PACS. Multivariate logistic analysis was performed to explore the independent risk factors of ICAS-related acute MCAO.

Results:
A total of 55 patients with acute MCAO were identified, including twenty-five (45%) suffering from ICAS and thirty (55%) suffering from embolism. Compared with the embolism group, the ICAS group were more often to be male (
P
= 0.04) and less often to have atrial fibrillation (
P
= 0.007), had smaller core volume (
P
= 0.001), and had shorter major core length (
P
= 0.001). Multivariate logistic analysis showed that no history of atrial fibrillation (aOR, 4.71, [95% CI, 1.29 to 17.19], P = 0.02) and shorter major core length (aOR, 0.66, [95% CI, 0.49 to 0.88], P = 0.005) were two independent risk factors of ICAS-related acute MCAO. Non-confluent core, defined as core with major core length less than 3.3 cm, was more often seen in the ICAS group (P < 0.001). For prediction of ICAS-related acute MCAO, the sensitivity, the specificity, and the accuracy of the non- confluent core was 72%, 87% and 80%, respectively.

Conclusion:
Non-confluent core in the baseline CTP image can be used to identity ICAS-related acute MCAO.

Key words:
middle cerebral artery occlusion, intracranial atherosclerotic stenosis, embolism, computed tomography perfusion, non-fused core
Abstract TP88: Deep Learning-based Automatic Detection And Segmentation Of Hyperdense Artery Sign On Non-contrast Computed Tomography In Acute Ischemic Stroke
Authors: Tsuji Hirofumi
Published: February 2023

Introduction:
CT- or MR-angiography(CTA/MRA) is the golden-standard to evaluate the site of large vessel occlusion (LVO). However, there are cases in which occluded vessels can be recognized as a hyperdense artery sign (HAS) on non-contrast CT (NCCT). If the HAS is detectable from NCCT, it may lead to a significant reduction in the time to start treatment. In this study, we developed and validated the deep learning model to detect the HAS on NCCT.

Methods:
This study used three multicenter retrospective datasets; ischemic stroke patients with LVO (occlusions of the intracranial internal carotid artery (ICA) and middle cerebral artery M1/M2 segments) who underwent mechanical thrombectomy, ischemic stroke patients without LVO, non-stroke patients. For developing the deep neural network model, positive samples (182 ICA/M1 and 57 M2 occlusion patients) were selected from stroke patients with LVO wherein the HAS was visible on NCCT. The decision for HAS visibility was made by two Neuro-interventionalists who referred to paired MRA/CTA of the same patient. While doing so, they also manually labeled the HAS regions on NCCT. Negative samples (592 patients) were collected from stroke patients without LVO and non-stroke patients. We split the data into training, validation and test sets. After we trained and validated the model, its performance was evaluated on the test set. The performance was measured using the metrics of sensitivity and specificity.

Results:
The sensitivity of the model was 0.78 (49/63) for ICA/M1 and 0.77 (10/13) for M2 occlusion patients. The specificity of the model was 0.61 (33/54) for stroke patients without LVO and non-stroke patients.

Conclusions:
The performance of our deep learning-based method to automatically detect the HAS on NCCT is close to that of expert physicians reported in earlier studies, and our method may lead to further improvement of patient prognosis by shortening the time to start treatment.
Abstract TP97: Automated Assessment Of DWI-FLAIR Mismatch To Predict Stroke-onset Time
Authors: Tavakkol Elham , Kihira Shingo , McArthur Mark , Ann Phoebe , Polson Jennifer , Zhang Haoyue , Arnold Corey , Yoo Bryan , Linetsky Michael , Ledbetter Luke , Salamon Noriko , Jahan Reza , Duckwiler Gary , Saver Jeffrey L , Liebeskind David S , Nael Kambiz
Published: February 2023

Background and Purpose:
DWI-FLAIR mismatch is used to determine thrombolytic eligibility in patients with acute ischemic stroke (AIS) when time-to-stroke symptom (TSS) is unknown. Advances in artificial intelligence and machine learning (ML) techniques have shown promising results in automated assessment of TSS. We aimed to use the e-Stroke software (Brainomix, Oxford, UK) to automatically classify DWI-FLAIR mismatch in a cohort of patients with AIS and in a comparative analysis with an expert neuroradiologist.

Methods:
In this retrospective study, consecutive patients with AIS who had pretreatment MRI, and known TSS were included. DWI-FLAIR mismatch was evaluated by an expert neuroradiologist blinded to TSS. e-Stroke software, which uses a combination of statistical methods and ML classification techniques was used to automatically classify DWI-FLAIR status. TSS was dichotomized using a 4.5 hr cutoff to assess the diagnostic performance of the radiologist vs. e-Stroke software.

Results:
Thus far 113 patients are included, 53 female, age (mean ± SD): 68.9 ± 17. TSS was 371±249 min (mean ± SD) and the infarct volume was 16.4±26.5 ml (mean ± SD). A total of 60 patients had TSS > 4.5 hrs while 53 had TSS < 4.5 hrs. Diagnostic performance (sensitivity/specificity/accuracy in %) for determination of TSS using DWI-FLAIR mismatch was 75/58.5/66.7 for the radiologist and 43/85/64 for e-Stroke software; without statistical difference (AUC: 0.66 for radiologist, 0.64 for e-Stroke; Delong test, p= 0.59). Subgroup analysis of infarctions of at least 1mL or higher, improved the diagnostic performance for both radiologist (83.8/59.4/71.6) and e-Stroke software (66.7/75.0/71.0), without statistical difference (AUC: 0.71 for radiologist and 0.71 for e-Stroke; Delong test, p= 0.96).

Conclusions:
Results show that fully automated quantitative approach for DWI-FLAIR mismatch provides similar diagnostic accuracies to expert neuroradiologist in determination of TSS.
Abstract WMP105: Gluteofemoral Fat Distribution Is Associated With Decreased Stroke Risk: A Mendelian Randomization Study
Authors: Myserlis Evangelos Pavlos , Georgakis Marios K , Mayerhofer Ernst , Parodi Livia , Rosand Jonathan , Anderson Christopher D ,   NINDS-SiGN
Published: February 2023

Introduction:
Previous studies have suggested that increased body fat is associated with stroke risk. Advances in imaging-based fat distribution measurements have uncovered distinct biological underpinnings of local fat depots. Here, we explored associations between biologically relevant local adiposity profiles and stroke risk, aiming to refine the association between body fat distribution and stroke.

Methods:
Utilizing data from Genome-Wide Association Studies of MRI-derived visceral (VAT), abdominal subcutaneous (ASAT) and gluteofemoral (GFAT) adipose tissue volumes in the UK Biobank (n= 37,750), we selected genome-wide (p<5x10
-8
), independent (r
2
<0.01), BMI- and height-adjusted variants associated with each trait. We performed Mendelian Randomization (MR) analyses of each trait on ischemic stroke (n=34,217) and subtypes (large artery (LAS)=4,373; cardioembolic (CES)=7,193; small vessel (SVS)=5,386) in MEGASTROKE. We performed multivariable MR, adjusting for relevant cardiometabolic factors (low-density lipoprotein, systolic blood pressure, type 2 diabetes, coronary artery disease). Estimates were expressed as per liter increase in fat volume.

Results:
GFAT distribution was associated with an overall decreased risk of ischemic stroke (OR 0.89; 95% CI: 0.82-96; p=0.04), mainly driven by SVS risk (OR 0.76; 95% CI: 0.64-0.88; p<0.001)
(Figure 1A).
Associations were largely consistent in weighted-median and MR-Egger analyses. After adjusting for cardiometabolic factors, only the association between GFAT and SVS remained significant
(Figure 1B)
. Neither VAT nor ASAT volumes were associated with ischemic stroke risk (both p>0.05).

Conclusions:
GFAT distribution is associated with a favorable stroke risk profile, suggesting that increases in stroke risk in the setting of an unhealthy body fat distribution may potentially primarily be driven by relative decreases in GFAT rather than increases in VAT or ASAT.
Abstract WMP12: Initial Severity And Functional Outcomes Of Acute Ischemic Stroke With Atrial Fibrillation On Direct Oral Anticoagulants(DOACs): Japan Stroke Data Bank
Authors: Yamashiro Takayuki , Wada Shinichi , Yoshimura Sohei , Toyoda Kazunori , nakai michikazu , Sasahara Yusuke , Shiozawa Masayuki , Koge Junpei , Ishigami Akiko , Miwa Kaori , Iwanaga Yoshitaka , Miyamoto Yoshihiro , Koga Masatoshi ,   Japan Stroke Data Bank Investigators
Published: February 2023

Purpose:
The purpose of this study was to examine the associations between oral anticoagulants (OACs) at onset and outcomes in acute ischemic stroke (AIS) patients with atrial fibrillation.

Methods:
AIS patients with comorbidity of atrial fibrillation (aged ≥18 years, pre-stroke modified Rankin Scale [mRS] 0-2) admitted within 24 hours after onset from January 2017 to December 2020 were examined from a long-lasting nationwide hospital-based multicenter prospective registry, the Japan Stroke Data Bank. Patients were classified into 3 groups according to anticoagulants at onset: no-anticoagulant group, warfarin group and DOAC group. The co-primary outcomes were the National Institutes of Stroke Scale (NIHSS) on admission and favorable outcome at discharge, corresponding to the mRS of 0-2. Mixed effects logistic regression was performed to examine the association between antithrombotic agents and these outcomes.

Results:
Of a total of 6,838 patients, 4,249 (62.1 %) patients were classified into the no-anticoagulant group, 907 (13.3 %) into warfarin group and 1,682 (24.6 %) into DOACs group. Median NIHSS score on admission was 7 [interquartile range: 2-19] in the warfarin group and 5 [2-15] in the DOAC group, versus 9 [3-20] in the no-anticoagulant group. Both warfarin and DOAC groups had lower NIHSS scores as compared to no-antithrombotic group (adjusted incidence rate ratio 0.96 [95% confidence interval 0.94-0.99] and 0.81 [0.79-0.83], respectively) after adjustment by age, sex, hypertension (HT), dyslipidemia (DL), diabetes mellitus (DM) and history of stroke. The rate of favorable outcome at discharge was 41.5 % in no-anticoagulant group, 42.0% in warfarin group and 48.1 % in DOACs group. In multivariable analysis, sex, NIHSS on admission, HT, DL, DM, history of stroke and intravenous thrombolysis and mechanical thrombectomy, DOACs group more frequently had favorable outcome (odds ratio 1.20 [95% CI 1.03-1.40]) than no-anticoagulant group, but warfarin group did not (1.05 [0.86-1.27]).

Conclusion:
Taking DOACs prior to onset appears associated with milder stroke severity and a more favorable outcome following acute ischemic stroke in patients with atrial fibrillation.
Abstract WMP13: Implementation Issues Arising From Less-intense Monitoring In Routine Care: Process Evaluation Of The Optimial Post Rtpa-iv Monitoring In Acute Ischemic Stroke (OPTIMISTmain) Study
Authors: Ouyang Menglu , Gonzalez Francisca , Montalbano Michelle , Pruski April , Iacobelli Michael , Wang Xia , Faigle Roland R , Johnson Brenda J , Summers Debbie , Jan Stephen , Urrutia Victor C , Anderson Craig S , Liu Hueiming
Published: February 2023

Background and Aims:
OPTIMISTmain is an international, multicenter, stepped-wedge cluster randomized trial to determine effectiveness and safety of less-intensive versus standard monitoring in thrombolysis-treated patients with mild-moderate acute ischemic stroke. A process evaluation was undertaken to determine feasibility, acceptability, and impact of the intervention on care processes, experience and staffing.

Methods:
A sample of stroke care nursing managers and unit staff from 7 US sites were invited to participate in semi-structured interviews at an early stage of the study. Implementer clinician surveys were undertaken pre- and post-intervention to define integration of the intervention. Qualitative data were independently analyzed by 2 coders; survey data reported from descriptive analysis.

Results:
19 nurses were interviewed from the units with 1:2 to 1:6 nurse-to-patient ratios. Less-intensive monitoring was well accepted: less time constraints and improved workload, and perceived to be cost efficient from improved use of neuro-intensive care beds. Some nurses had initial safety concerns over missing deteriorating patients. Less-intensive monitoring led to patients being less irritable and more cooperative from having more rest. There was greater flexibility in the allocation of nursing staff from workforce shortages arising due to the COVID pandemic. Similar results were evident in the survey (13 hospitals, 34 respondents): 80% of respondents agreed that less-intensive monitoring benefited work; 74% believed it should be widely adopted at a national level. Nurses reported time being freed up to provide more patient education (56%), continence/daily living care (50%), early mobilization (26%), mood/cognition assessment (44%), and other aspects (24%, e.g. communication, family support).

Conclusions:
Less-intensive monitoring after thrombolysis for acute ischemic stroke patients appears feasible and acceptable among US healthcare professionals.
Abstract WMP14: Status And Influencing Factors Of Rehabilitation Exercise Compliance In Young And Middle-aged Patients With Hemorrhagic Stroke Based On The Hapa Model: A Multi-center Cross-sectional Survey
Authors: Chen Lu
Published: February 2023

Background and Purpose:
Exercise rehabilitation is the preferred rehabilitation therapy for stroke patients, but exercise compliance of patients is generally low. The study aimed to investigate and analyze the status and influencing factors of rehabilitation exercise compliance in young and middle-aged patients with hemorrhagic stroke.

Methods:
Convenience sampling method was adopted to select 397 young and middle-aged hemorrhagic stroke patients from three hospitals in central, eastern and northern China from July 2021 to January 2022 in accordance with the geographical classification standards of the National Bureau of Statistics and multi-center research cooperation. According to the Health Action Process Approach(HAPA), the general data survey scale, stroke functional exercise compliance Scale, exercise self-efficacy scale, exercise plan scale, stroke health belief scale and self-care ability scale were used for cross-sectional investigation.

Results:
The total score of exercise compliance in young and middle-aged stroke patients was (43.46±9.58), and the average compliance rate was 77.60%, which was in the middle level. Multivariate regression analysis showed that total score of exercise self-efficacy, total score of exercise program, perceived susceptibility, perceived severity, perceived benefit, perceived obstacle, health motivation and self-efficacy were the influencing factors of exercise compliance in young and middle-aged stroke patients (
P
< 0.05).

Conclusions:
According to the HAPA model, clinical medical staff should accurately evaluate the rehabilitation exercise stage of patients, and formulate and implement stroke rehabilitation exercise strategies according to the actual situation of patients and various possible influencing factors, so as to improve the exercise compliance of patients, improve their functional status, and further improve their quality of life.
Abstract WMP15: Health Belief And Exercise Adherence Of Young And Middle-aged Stroke Patients: A Moderated Mediation Model Of Planning And Exercise Self-efficacy
Authors: Chen Lu
Published: February 2023

Background:
Health belief and exercise self-efficacy are meaningful protective factors that help individuals maintain health. However, few studies have explored their impact on planning and exercise adherence.

Purpose:
To explore the mediating role of planning in the impact of health beliefs on exercise compliance in young and middle-aged stroke patients, and the regulatory role of exercise self-efficacy in this mediating model.

Method:
Convenience sampling method was used to select 369 young and middle-aged patients with hemorrhagic stroke from 3 Grade A hospitals in China from July 2021 to May 2022. General data questionnaire, stroke health belief Scale, exercise self-efficacy scale, exercise plan scale and functional exercise compliance scale were used to investigate.

Results:
Health belief was positively correlated with exercise self-efficacy, planning and exercise compliance (
r
=0.136, 0.531, 0.529, all
P
<0.01). The indirect effect of health belief on exercise compliance in young and middle-aged stroke patients was 0.206 (95%
CI
: 0.158-0.259), and the direct effect was 0.167 (95%
CI
: 0.106-0.229), indicating that planning played an intermediary role between health belief and exercise compliance, accounting for 55.23%. Using the PROCESS macro (model 8) test, it was found that sports self-efficacy had a regulating effect, and had a significant interaction between planning and sports compliance(
β
=0.009, 95%
CI
: 0.001-0.018;
β
=0.008, 95%
CI
: 0.001-0.014).

Conclusion:
Health beliefs and plans can improve the exercise compliance of young and middle-aged stroke patients, and this benefit is related to exercise self-efficacy. We should enhance the health beliefs of patients, improve their exercise self-efficacy, encourage them to make exercise plans, and then improve their exercise compliance.
Abstract WMP16: Understanding The Experience Of Fatigue Poststroke: Preliminary Results From A Mixed-methods Longitudinal Study
Authors: Teng Chiao-Hsin , Davis Leslie L , Anderson Ruth A , Bryant Ashely L
Published: February 2023

Introduction:
The first 6 months poststroke is an important period for stroke survivors to regain physical function but fatigue may affect recovery. The challenges faced regarding fatigue level and physical function in the first 6 months poststroke remains unknown. Stroke survivors have reported that carepartners play an important role in their recovery but the specific support by carepartners is not well-addressed in the literature.

Methods:
Our ongoing longitudinal cohort study uses concurrent mixed-methods to determine the interrelationship between how stroke survivors adapt to and experience changes in fatigue and recovery of physical function during the index hospitalization, 1, 3, and 6 months poststroke. Thirty stroke survivors with first-ever ischemic stroke and 10 of their carepartners will be enrolled. In the quantitative arm of the study, 30 stroke survivors are asked about fatigue levels (Fatigue Severity Scale [FSS]) and physical function (Stroke Impact Scale-16 [SIS-16]) at 4 time points. The qualitative arm explores stroke survivors’ (n=10 of 30) and carepartners’ perspectives about adaptation to poststroke fatigue at the same time points. Matrices are being used to depict longitudinal adaptation (i.e., how stroke survivors’ adaptive strategies vary across the fatigue levels and physical function during the index hospitalization, 1, 3, and 6 months poststroke). We anticipate completing enrollment by October 2022.

Results:
To date, 17 stroke survivors (mean age 63±15.5 years; 47.1% female; 29.4% Black with a mean NIHSS score of 4.9±4.1) and 7 carepartners have been enrolled. The mean FSS score at baseline (before the index stroke; n= 17) is 36.3±14.1 and 35.0±14.1 (n=11) at 1-month poststroke. The mean SIS-16 score at baseline (n= 17) is 70.6±9.7 and 55.9±20.2 (n=11) at 1-month poststroke.

Conclusions:
To date, we have enrolled a racially, ethnically, and gender diverse sample of stroke survivors who reported mild-moderate fatigue which persisted beyond hospital discharge at 1 month. While functional status improved at 1 month for stroke survivors, it has not returned to their baseline. Our findings will increase knowledge about longitudinal changes in early fatigue and physical-function recovery among stroke survivors.
Abstract WMP22: Effects Of Visual Arts-based Interventions On Physical And Psychosocial Outcomes Among Stroke Survivors: A Systematic Review And Meta-analysis
Authors: Chan Mimi Wai Man
Published: February 2023

Background:
Visual arts-based interventions may have potential effects on post-stroke physical and psychosocial outcomes, but the current evidence is unclear.

Objectives:
(1)To determine the effects of visual arts-based interventions on physical and psychosocial outcomes among stroke survivors, and (2)to identify the best practice of visual arts-based interventions that have optimal effects on physical and psychosocial outcomes among stroke survivors.

Methods:
Seventeen databases were searched. Two reviewers independently screened for the eligible studies, appraised methodological quality assessment, and extracted data. Methodological quality was assessed using the revised Cochrane risk of bias tool for randomised trials. Meta-analysis was conducted using Review Manager 5.4, and narrative synthesis was performed if there was insufficient data for meta-analysis. Grading of Recommendations Assessment, Development and Evaluation was adopted to assess the certainty of evidence.

Results:
Seven studies were included in this review. The pooled results suggested that visual arts-based interventions had significant effects on activities of daily living (SMD: 0.96, 95%CI: 0.24 to 1.69,
p
=0.009,

I
2

=87%), upper limb function (SMD: 0.83, 95%CI: 0.42 to 1.24,
p
<0.0001;

I
2

=6%), and depressive symptoms (SMD: -1.14, 95%CI: -1.67 to -0.61,
p
<0.0001,

I
2

=70%). While the effect on hand function (SMD: 0.47, 95% CI: -0.43 to 1.37,
p
=0.31;

I
2

=82%) and anxiety (SMD: -0.80, 95%CI: -1.71 to 0.11,
p
=0.08;

I
2

=86%) were non-significant. Narrative synthesis showed that the effects of visual arts-based intervention on self-efficacy, social participation, and quality of life were uncertain. This review also found that five non-visual art activities with education, task orientation, sharing, feedback, and support as parts of the component of visual arts-based interventions might contribute to the benefits of physical and psychosocial outcomes after stroke.

Conclusion:
This review found that stroke survivors may benefit from visual arts-based interventions to improve physical and psychosocial outcomes. However, the quality of evidence was relatively low, further rigorous randomised controlled trials are recommended to strengthen the current evidence.
Abstract WMP24: Developing Interactive Maps To Visualize Wisconsin’S Regional Stroke Systems Of Care
Authors: Bluma Dot , Bowser John , Xiong Ka , Swander Lena
Published: February 2023

Background and Purpose:
Many rural patients experiencing complex strokes are transferred from small hospitals with limited stroke-specific resources (spoke) to larger hospitals (hub). The Wisconsin (WI) Coverdell Stroke Program (Coverdell) utilized the Get with the Guidelines®-Stroke registry to determine the frequency of this spoke-to-hub transfer occurrence in WI in 2020, which was found to be 24.6%. This suggested a need for interactive maps to visualize stroke systems of care (SSoC) linkages between hubs and spoke hospitals across Wisconsin.

Methods:
In 2021, Coverdell partnered with eight Stroke Coordinators across five WI public health regions. Stroke Coordinators identified hospital transfer connections in their region where transfers occurred 25% or more of the time. With this data, Coverdell developed maps to visualize transfer lines between hospitals with estimated driving distances and transport times via ambulance. User testing, promotion, and publishing to the WI Department of Health Services Chronic Disease website was completed in April 2022.

Findings:
As of July 1, 2022, our maps have had 389 page views and 272 unique page views. These counts exclude DHS Internet Protocol traffic. Our interactive maps visualize transfers across WI and allow users to select individual hospitals to investigate relationships. We discovered a paucity of certified hospitals and stroke transfers in rural and northern WI.

Conclusion:
These maps can assist hospitals and Emergency Medical Service providers to visually identify where stroke patients are transported to. In addition, they can help state stroke programs and partners to recognize gaps in SSoC. The maps are a resource for those working with high-risk stroke populations to understand resources available in their communities and wider geographic areas. They also provide a visual representation for policy makers of locations where stroke services may be inadequate.
Abstract WMP25: Female And Minority Participants Are Underrepresented In Stroke Motor Recovery Trials Over The Last Decade
Authors: Hassani Sara , Heffron Lindsay , Feng Wayne
Published: February 2023

Introduction:
Inclusion of diverse stroke patient populations is key for generalizable and clinically meaningful stroke rehabilitation clinical trials. The aim of this study was to assess 1) the reporting and inclusion of race, ethnicity, and gender in publications on motor recovery clinical trials post-stroke, and 2) the quality of the clinical trial.

Methods:
All stroke motor recovery clinical trials published in ten leading rehabilitation journals in the United States between 2012 and 2021 with at least one control group were identified. The percent of different racial minorities, ethnicities, and women enrolled in the trials was extracted and calculated for those trials with available data found in the manuscript or on clinicaltrials.gov. The quality of the trial was determined by the PEDro score.

Results:
57 trials (total of 3004 participants) met the inclusion criteria and were included in the analysis. 97%, 37%, and 23% of the trials included reported enrollment by gender, race, and ethnicity, in the manuscript or on clinicaltrials.gov. Among trials reporting race, 59% of participants were White, followed by 30% Black, 1% Native American, 4% Asian and 10% Other. Among the trials that reported ethnicity, Hispanic or Latino participants were represented as 10% of the total participants. The average PEDro score was 7.

Conclusions:
While most stroke rehab trial publications were of good quality and reported data on sex, they did not report race/ethnicity, though this information was collected on clinicaltrials.gov. Improvement in the inclusion and reporting of race/ethnicity in stroke motor recovery trials is needed to allow for better generalizability in the future.
Abstract WMP27: Augmenting Early Prediction Of Post-Rehabilitation Ambulation Ability And Risk Of Falling Status For Recovering Stroke Patients Using Wearable Sensors And Machine Learning
Authors: Khazanchi Rushmin , Lanotte Francesco , O'Brien Megan , Jayaraman Arun
Published: February 2023

Introduction:
Inertial measurement units (IMU) can capture objective biomarkers of recovery during everyday activity paving the way to early prognosis and personalized therapy in post-stroke rehabilitation. In this study, we evaluated the performance of IMU data incorporated into machine learning models to predict discharge abilities compared to models based on traditional clinical variables.

Methods:
32 subacute stroke patients admitted to inpatient rehabilitation performed clinical tests while wearing IMU sensors placed on the pelvis and both unaffected and affected-side shanks (US, AS). Variables collected were patient information (PI), clinician-scored functional assessments (FA), signal-processed IMU data during the 10-Meter Walk Test (IMU
10MWT
) and the Berg-Balance Scale (IMU
BBS
). Patients were identified as
household
or
community
ambulators (Amb), and with
high
or
normal
risk of fall (RoF) based on discharge functional scores. A class-weighted L1-penalized logistic regression model was trained using nested leave-one-out cross-validation on admission data to predict discharge Amb and RoF statuses. The impact of sensor data on model performance was assessed on three feature sets: PI+FA, PI+IMU
10MWT/BBS
, PI+FA+IMU
10MWT/BBS
. Evaluation metrics included: weighted F1 score (WF1), accuracy, log-loss, and feature importance.

Results:
The PI+FA+IMU
BBS
, and both the PI+IMU
10MWT
and PI+FA+IMU
10MWT
models, outperformed the PI + FA benchmark model for RoF and Amb prediction, respectively, across all metrics (Figure 1). US gyroscopic and AS/US acceleration were relevant for Amb prediction, while the admission BBS score and pelvic acceleration were important to RoF prediction.

Conclusions:
Incorporation of simple IMU data from admission can improve discharge functional predictions over a model using PI and FA. Early, accurate predictions of post-stroke recovery could facilitate more personalized and efficient rehabilitation strategies.
Abstract WMP3: A Five-minute Delay From Bolus Injection To Infusion Halves Plasma Concentration Of Tissue Plasminogen Activator
Authors: Kobayashi Yuya , Saito Takuya , Kawabata Yuichi , Igari Takako , Kondo Yasufumi , Yamamoto Kanji
Published: February 2023

Objectives:
Reducing the time between the onset of cerebral infarction and treatment with tissue plasminogen activator improves the prognosis of patients with cerebral infarction. Diverse dosing protocols have been developed with the aim of reducing the time to a bolus injection; however, only few studies have investigated the methods and effects of the interrupted time between bolus and postbolus infusion. Hence, we evaluated the impact of this interruption on pharmacokinetics.

Materials and Methods:
We calculated the changes in alteplase concentration after a bolus injection with high precision, in relation to different interval times. Simulations were performed using the linpk package of the statistical analysis software R. Postbolus infusion was initiated 0, 5, 15, or 30 min intervals after bolus dosing. The calculation interval was set as 6 s.

Results:
Alteplase concentration rose to 1.23 mg/ml following bolus dosing. However, it dropped to 0.53 mg/ml (43.4%) during a 5-min interval, 0.27 mg/ml (22.23%) during a 15-min interval, and 0.10 mg/ml (8.38%) during a 30-min interval.

Conclusion:
Because of the short half-life of alteplase, even a short delay in initiating postbolus infusion can cause a significant reduction in the serum alteplase concentration.
Abstract WMP38: One Year Medicare Spending On Beneficiaries In Atrial Fibrillation Not Being Treating With Long-term Anticoagulants Experiencing A Hospitalization For Ischemic Stroke
Authors: Culler Steve , Simon April W , Peacock William F
Published: February 2023

Background:
It is well known that individuals in atrial fibrillation (AF) who are not using anticoagulants are at higher risk of Ischemic Stroke (IS). These hospitalizations result in the utilization of significant healthcare resources in addition to reducing patients’ quality of life. The purpose of this study is to estimate how much the Medicare program spends treating a Medicare beneficiary (MB) with AF who are not being anticoagulated with an IS hospitalization and the 12-months following discharge.

Method:
The study population consisted of all MBs in the fee-for-service program who had a hospitalization for IS and were discharged between January 1, 2018 to December 31, 2018. A total of 50,509 MBs met the study inclusion criteria and were not excluded due to prior history of stroke or on long-term anticoagulants. The study period for accumulating Medicare spending at healthcare facilities is for the index hospitalization and all facility claims that occurred within 12-months of the index hospital discharge date.

Results:
Average total Medicare spending per MB for the study population was $46,867±$49,212 resulting in total Medicare spending of nearly $2.5 billion during the study period. Highest average spending per MB was for hospital services $25,848 (of which $15,790± $20,984 occurred during the index hospitalization and $10,058±$21,956 during readmission during the follow-up period. The Medicare program also spent over $3,000 per study patient at skilled nursing facilities ($8,131±$14,979), rehabilitation facilities ($5,538±$12,739), and outpatient facilities or emergency departments ($3,056±$7,495). At least, 19% of MB died during the study period. Medicare spent $25,397±$30,259 on those MBs that died during their index hospitalization and $67,276±$65,021 on those MBs that survived their index IS hospitalization but died during the follow-up period.

Conclusion:
MBs with AF who are not being treated with anticoagulants and suffer an ischemic stroke result in one-year Medicare Part A program spending of approximately $47,000 per person compared to the average Medicare spending for all services of approximately $12,000 per beneficiary in 2018. Identification of MB in AF and treatment with anticoagulants would save CMS significant dollars.
Abstract WMP45: Cryptogenic Stroke Patients With Active Cancer: Characteristics, Treatment And Outcomes Using Population Based Registries
Authors: Chirumamilla Siri , Ido Moges , Bayakly Rana , Nahab Fadi B
Published: February 2023

Background:
The objective of our study was to evaluate the frequency, predictors, and outcomes of cryptogenic stroke (CS) patients with malignancy.

Methods:
We linked data from the Georgia Coverdell Acute Stroke Registry from 2017-2019 and the Georgia Cancer Registry from 2016-2019 for a population based cross-sectional study; to determine the frequency, treatment, and outcomes of CS patients who were newly diagnosed with active cancer within one year before and after the CS. We compared baseline characteristics and outcomes of patients with active cancer (CS+) versus patients without active cancer (CS-).

Results:
Of the 3,686 CS patients, 145 (4%) were CS+ of which 90 (62%) were diagnosed after the CS (median 69 days). Compared with CS- patients, CS+ had more venous thromboembolism (VTE) history (6% vs 1%, p = 0.0001), less hypertension (68% vs 77%, p = 0.009) and diabetes (28% vs 37%, p = 0.028). Also, CS+ patients were less likely to receive IV tPA (9.7% vs 15.6%, p=0.059); more likely to undergo Mechanical Thrombectomy (9% vs 4%, p=0.004); less likely to be discharged with antiplatelets (84% vs 95%, p < 0.001); more likely to be discharged with anticoagulants (23% vs 11%, p < 0.001); and more likely to be discharged on both antiplatelet and anticoagulant therapies (13% vs 6%, p =0.006) than CS- patients. CS+ patients were less likely to be discharged home (49% vs 61%) and skilled nursing or rehabilitation facilities (26% vs 33%) but more likely to be sent to hospice or expire (23% vs 4%, p < 0.001).

Conclusions:
Only 4% of CS patients had active malignancy and were more likely to have a history of VTE. Active malignancy patients were less likely to receive IV tPA but more likely to undergo thrombectomy. Given nearly half of CS+ patients were discharged home, further study is needed to refine antithrombotic and revascularization therapy in these patients.
Abstract WMP49: Occult Contrast Retention Post-thrombectomy On 24-hour Follow-up CT: Associations And Impact On Imaging Analysis
Authors: Pham Jenny , Gan Calvin , Dabboucy Jasmin , Stella Damien , Dowling Richard , Yan Bernard , Bush Steven , Williams Cameron , Mitchell Peter J , Desmond Patricia , Thijs Vincent , Asadi Hamed , Brooks Mark , Maingard Julian , Jhamb Ash , Pavlin-Premrl Davor , Campbell Bruce , Ng Felix
Published: February 2023

Introduction:
CT performed 24h post-treatment is widely used to assess radiological outcomes in stroke studies. Even without visible hyperattenuation, occult angiographic contrast may persist in the brain and confound Hounsfield Unit-based imaging metrics such as Net Water Uptake (NWU), a measure of cerebral edema based on tissue hypoattenuation. We aimed to assess (1) the presence of retained contrast post-thrombectomy on 24h CT by comparing NWU measurements with and without adjustment for iodine using dual energy CT (DECT), (2) factors associated with amount of retention, and (3) its impact on the accuracy of NWU.

Methods:
In a prospective study of patients with anterior circulation large vessel occlusion who had post-thrombectomy follow-up DECT performed 24h post-treatment from two Comprehensive Stroke Centres (November 2021 to May 2022), NWU was calculated by interside comparison of Hounsfield Units of the infarct lesion and its mirror homolog. Retained contrast was quantified by the difference in NWU values with and without adjustment for iodine. We tested correlation between NWU and tissue swelling using relative hemispheric volume (rHV) and midline shift (MLS). Patients with visible hyperdensities from hemorrhagic transformation or visible contrast retention, and bilateral infarcts were excluded.

Results:
Of 125 patients analysed (median age 71 [IQR 61-80], baseline NIHSS 16 [IQR 9.75-21]), reperfusion (eTICI 2b-3) was achieved in 120 patients (96.8%). NWU measured with iodine adjustment was significantly higher than NWU measured without adjustment (17.1% vs 10.8%, p<0.001). In multivariable median regression analysis, age (p=0.031), number of passes (p<0.001) and having CT perfusion at baseline (p=0.008) were independently associated with amount of retained contrast. NWU measured with iodine adjustment correlated with rHV (p=0.043) and MLS (p=0.033), but NWU without adjustment did not (rHV p=0.350; MLS p=0.347).

Conclusion:
Occult angiographic iodine contrast significantly affects NWU on CT at 24h. Our data suggest adjustment for retained iodine using DECT is required for accurate NWU measures post-thrombectomy. Future studies analysing CT post-thrombectomy should consider the significance of occult contrast retention.
Abstract WMP52: Markers Of Endothelial Glycocalyx Damage In Patients Withvascular Cognitive Impairment Associated With Cerebral Small Vessel Disease
Authors: Martins-Filho Rui Kleber , Rodrigues Guilherme , Zanon Zotin Maria C , Camilo Millene , Goulart Thiago , Nather Júnior Júlio César , Alessio-Alves Frederico , DIAS FRANCISCO A , Pontes-Neto Octavio M
Published: February 2023

Introduction:
Cerebral small vessel disease (cSVD) involves a myriad of pathogenic mechanisms affecting small vessels of the brain, leading to a significant impact on motor and cognitive functions, and it is the main cause of Vascular cognitive impairment (VCI). The endothelial glycocalyx (EG), the layer lining the vascular endothelium, has a pivotal player in maintaining the proper function of neurovascular unit, and its degradation may be involved in VCI due to cSVD.

Objectives:
to investigate the relationship between markers of EG damage and VCI related to cSVD.

Methods:
Cross-sectional study based on clinical data and serum samples for the quantification of EG damage markers (syndecan-1, hyaluran) of VCI related to cSVD patients and of a control group derived from a dataset of healthy workers from the same institution. We used an automatic logarithm for segmentation and volumetric evaluation of white matter lesions on brain MRI of the patients. Logistic regression models and c-statistics were used to identify the independent variables related to VCI and investigate the accuracy of syndecan-1 to detect VCI. We studied the association of thebiomarkers and MoCA scores, index of independence in activities of daily living and whitematter lesion burden respectively.

Results:
Between July 2019 and March 2020, we studied 22 patients with VCI associated with cSVD and compared them with a dataset of 22 healthy workers from the same institution. Patients with VCI were older, had a higher prevalence of diabetesmellitus and hypertension, had a worse index of independence for daily activities, and higherlevels of syndecan-1 (78,4 vs 24; p < 0,01). There was no difference in hyaluran levels between both groups. In multivariate analysis, only age (OR 1,35;CI 1,04 - 1,76; p = 0,02) and syndecan-1 levels (OR 1,08;CI 1,01 - 1,15;p = 0,01) related to VCI. The ROC curve ofsyndecan-1 levels to predict VCI had a area under de curve of 0,78 (CI 0,64 - 0,92) and there was a correlation between syndecan-1 levels and MoCA scores (rho = - 0,34;p = 0,02). There were no correlations between syndecan-1 and hyaluran levels and index of independence and white matter lesion burden respectively.

Conclusions:
Syndecan-1, but not hyaluran, is a potential biomarker for VCI associated with cSVD.
Abstract WMP55: Up-front Ct Angiography Of The Head And Neck Imaging For Patients With Low NIH Stroke Scale: Is There Utility?
Authors: Ro Jennifer C , Mohamed Ghada A , Issa Pamela , Nour Hassan A , Sutherly-Bhadsavle Loretta J , Anderson Aaron M , Winkel Daniel , Belagaje Samir R , Greene James G , Benameur Karima , Groover Olivia , Nahab Fadi B
Published: February 2023

Background:
Current guidelines encourage early vascular imaging to assess for large vessel occlusions (LVO) in patients presenting with NIHSS ≥ 6 to establish candidacy for mechanical thrombectomy (MT). In patients with low NIHSS, the benefit of early vascular imaging is uncertain. Cortical signs such as aphasia, neglect or visual field deficits on the exam have been used to identify patients with LVO. Still, the utility of these clinical signs in low NIHSS is unknown.

Methods:
This is a retrospective analysis of all acute ischemic stroke patients who presented directly to our comprehensive stroke center (CSC) from December 1, 2020-May 31, 2021. All patients had CT angiography (CTA) or MR angiography (MRA) of the head and neck with timing at the discretion of the treating neurologist.

Results:
Of the 167 patients [median age 70 IQR (58-78), 50% female, 64% African-American], 85 (51%) presented with NIHSS of 0-5. Compared to patients with NIHSS ≥ 6, patients with NIHSS of 0-5 were younger (median age 66 vs. 70, p= 0.039) and had less congestive heart failure (0.6% vs. 4.8%, p=.014). Upfront CTA with initial non-contrast CT head was done less in patients with NIHSS 0-5 (65% vs. 85%, p=.002). Patients with NIHSS 0-5 had fewer LVO (13% vs. 44%, p<.001), less IV tPA administration (7.1% vs. 22%, p=.006), less MT (2.4% vs. 27%, p<.001), and more posterior circulation strokes (42% vs. 13%, p<.001). Of the 11 patients with NIHSS 0-5 and an LVO, 4 (36%) had no cortical signs (aphasia, extinction, or visual field deficit) on the exam.

Conclusions:
The absence of cortical signs on exam in ischemic stroke patients presenting with NIHSS 0-5 does not exclude LVO. Our cohort with NIHSS 0-5 were less likely to have upfront CTA despite having LVO in 13% of cases. Early upfront vascular imaging should be considered to assess for LVO in all suspected acute ischemic stroke patients regardless of the presence of cortical signs.
Abstract WMP59: Effect Of Radiographic Contrast Media Shortage On Stroke Evaluation In The United States
Authors: Qureshi Adnan I , Grintal Ayam , DeGaetano Aimee C , Goren Maayan , Golan David , Hassan Ameer E
Published: February 2023

Background:
We quantified the effect of nationwide contrast media shortage, initiated on April 19
th
, 2002 after GE Healthcare rationing, on evaluation of acute ischemic stroke (AIS) patients.

Methods:
We analyzed the data on 41,926 AIS patients (46,157 studies) who underwent imaging processed with Viz.ai software at 185 hospitals in the United States from Feb 28, 2022 through July 11, 2022. We quantified the overall (and in various strata) percentage change in daily number of computed tomographic angiography (CTA) and perfusions (CTP) performed, and the change in proportion of patients with large arterial occlusion (LVO) identified and image quality (CTP quality warnings) before and after April 19
th
.

Results:
The daily counts of unique patients who underwent CTA decreased (a 14% reduction) in April: from 2.099 studies (before April 19
th
) to 1.811 studies (after April 19
th
) per day per hospital (see Figure). The reduction was most prominent in comprehensive stroke centers and in sites that used GE contrast media (24% versus 12%). There was no change in the proportions of patients with LVO identified (8.69% versus 9.34%) and inadequate tests (5.86% versus 5.00%).

Conclusions:
There was a prominent reduction in CTA performed in the United States due to contrast media shortage. However, the proportion of patients with LVO identified was not affected.
Abstract WMP74: Perfusion Delay Volume Predicts 90-day Recurrence In Symptomatic Anterior Circulation Intracranial Stenosis: A Two-center Study
Authors: Yaghi Shadi , Khatri Pooja , Prabhakaran Shyam , Gebregziabher Mulugeta , Liebeskind David S , De Havenon Adam H
Published: February 2023

Background:
Intracranial arterial stenosis (ICAS) can cause stroke by different mechanisms: perforator disease, artery to artery embolism, and impaired flow. There is limited data exists on the utility of perfusion imaging in patients with ICAS. We aim to determine associations between perfusion delay volume and 90-day recurrence in patients with anterior circulation ICAS.

Methods:
This is a two-center study of symptomatic anterior circulation ICAS involving the left M1 or ICA who underwent perfusion imaging (MRP or CTP). The primary predictor was hypoperfusion mismatch volume HPV (T max delay volume - core volume) using Tmax>4 sec or Tmax>6 sec thresholds. The outcome was recurrent cerebrovascular events (RCVE) defined as new or worsening neurological symptoms due to confirmed or suspected new infarct or infarct extension. We used Youden’s index to define the optimal cut-point of Tmax4 and Tmax6 mismatch for predicting recurrent stroke. We fit time-to-event models for RCVE with HPV at dichotomized cut-points, both as a univariate analysis and after adjusting for co-variates.

Results:
50 patients met the inclusion criteria and 30% had RCVE. The median T max 4 HPV in mL was higher in patients with vs. without RCVE (121 vs. 19, p < 0.001) and the median T max 6 HPV in mL was higher in patients with vs. without RCVE (33 vs. 0, p = 0.004). We found an association between Tmax> 4 sec hypoperfusion volume (AUC 0.79, p =0.012) and max>6 sec hypoperfusion volume (AUC 0.75, p = 0.008) with RCVE. For Tmax 4 the cut-point was at 94 mL and for Tmax6 the cut-point was at 10 mL. Recurrent stroke was higher in those with vs. without Tmax>4 sec ≥94 mL delay (66.7% vs. 14.3%, (p<0.001) and with vs. without Tmax>6 sec≥10 mL delay (68.8% vs. 11.8%, p<0.001). In separate adjusted Cox regression analyses, the adjusted hazard of Tmax>4 sec HPV ≥ 94 mL was 5.0 (95% CI 1.5-16.4) and that of Tmax>6 sec HPV > 8 ml was 11.3 (95% CI 3.7-116.8).

Conclusion:
In this two-center study, hypoperfusion delay volume is associated with early recurrence in patients with symptomatic ICAS. Studies are needed to validate our findings and to test endovascular reperfusion in the subset of patients with symptomatic ICAS and perfusion delay.