bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP48: Acute Ischemic Stroke Transfer Networks: Low Volume Ed-hospital Connections Are Common
Authors: Zha Alicia , Deligkaris Christos , Kerber Kevin A , Burke James F
Published: February 2023

Background:
Emergency Department (ED) transfers to tertiary centers are a critical component of stroke systems of care, yet little is known about the status of the transfer networks used to execute this process. Our objective is to characterize these transfer networks and assess rates of acute treatments among transfers to identify potential targets for improving organization of stroke systems of care.

Methods:
Using the 2017 US Centers of Medicare and Medicaid Inpatient and Outpatient Fee-for-Service files, we captured patients with inpatient ischemic stroke claims based on ICD 10 codes. We defined ED-hospital transfers as: 1) any outpatient ED claim ≤48 hrs prior to the inpatient stroke claim, 2) ED discharge status indicating an acute care hospital, and 3) originating and receiving facilities with different NPI numbers. We characterized the structure of transfer networks and acute treatment rates (based on ICD 10 codes and DRGs for thrombolysis and thrombectomy) using descriptive statistics.

Results:
We identified 225,177 patients with inpatient stroke claims. Of these, 7,907 (3.5%) had an ED-hospital transfer, involving 2083 different acute care hospitals. Amongst EDs that transferred a patient, the median number of receiving hospitals was 1 (IQR 1; range [1,7]) and the median volume of transferred patients was 3 (IQR 5; range [1,53]). Amongst hospitals that had stroke patients transfer in, the median number of originating EDs was 2 (IQR 5; range [1,28]) and the median volume of transferred patients was 5 [IQR 14; 1-158]. Amongst all ED-hospital transfer pairs, the median volume of transferred patients was 2 (IQR 2; range[1,53]). Amongst transferred patients, 60% received thrombolysis and 16% received mechanical thrombectomy.

Conclusions:
We found wide variation in the volumes of ED-hospital transfers for acute stroke, with a large number of these transfers occurring between hospitals with low transfer volumes. Given that high volume centers generally have better outcomes and the majority of identified transfers received acute therapies, a better understanding of the clinical circumstances driving these low-volume transfer connections is needed.
Abstract TP52: Post-acute Transition Of Care In Stroke Patients: A Systematic Review
Authors: Ibrikji Sidonie , Blaginykh Elena , Man Shumei , Uchino Ken
Published: February 2023

Background:
Post-acute transition of care (TOC) in stroke patients is a multifactorial process. Different TOC interventions have been tested, with inconsistent benefits.

Objective:
Our aim is to evaluate the effect of post-acute TOC interventions on various stroke patients’ outcomes.

Methods:
All published interventional studies evaluating the impacts of TOC models for stroke survivors, during their post-acute care disposition, were included. We excluded studies tackling only patients with intracerebral hemorrhage (ICH) or transient ischemic attacks, those with purely rehabilitative interventions, case reports and case studies, as well as systematic reviews and meta-analyses. We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) through July 2022.

Results:
We included 38 studies involving 82,416 patients. TOC services were heterogeneous, commonly including scheduled home visits, telephone calls and office visits, in the setting of a multidisciplinary approach. Outcome measurement time varied between 1 month and 5 years. Activities of daily living (ADLs)-related outcomes, functionality, quality of life (QOL)-related outcomes, readmission rates, mental health-related outcomes, and mortality were reported in 20, 11, 10, 10, 7, and 6 studies, respectively. Only 4 studies looked at rates of medication adherence and 2 studies at control of vascular risk factors. In 6 out of 10 studies, improvements in QOL measurements and patient-reported health surveys were reported, whereas no study reported improvement in mortality rates. Three studies showed improvement for each of the following outcomes: ADLs, functionality, and readmission rates. Only 2 studies noted decrease in mental health problems with the intervention, and 2 noted better control of vascular risk factors. Both studies with medication adherence outcomes showed that the intervention increases rates of compliance to prescribed drugs.

Conclusion:
Post-acute TOC interventions seem to have a positive effect on stroke survivors’ quality of life and self-perceived health, as well as on rates of medication adherence, but bear no effect on mortality.
Abstract TP53: Geomagnetic Storms Do Not Predict The Occurrence Of LVO Stroke Clusters Necessitating Endovascular Intervention
Authors: Kole Max , Alsrouji Owais , Fadel Hassan , Pawloski Jacob , Marin Horia , Chebl Alex
Published: February 2023

Intro:
Space weather induced geomagnetic storms have been associated with an increased risk of stroke occurrence. Data on image-proven, temporally related large vessel occlusion stroke (LVO) and geomagnetic storms are lacking. We sought to investigate this potential association to determine whether space weather forecasts can be used to predict incoming cluster events.

Methods:
Data from a Comprehensive Stroke Center were collected from January 1, 2017, to April 15, 2022. Space weather data were downloaded from the World Data Centre for Geomagnetism, Kyoto homepage (http://wdc.kugi.kyoto-u.ac.jp/kp/index.html#LIST) The indications for mechanical endovascular reperfusion (MER) were in accordance with the Guidelines for the Early Management of Patients With Acute Ischemic Stroke Regarding Endovascular Treatment: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Univariate binary logistic regression was performed to assess the potential associations between space weather data and LVO MER cases with 48 hour lag effect. Geomagnetic activity was defined by the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Centre (SWPC) space weather scales.

Results:
Of the 1931 days included in this study, there were 538 (27.86%) days with at least one LVO MER (450 (23.3%) with 1, 81 (4.19%) with 2, and 7 (0.36%) with 3. There were 1784 days without geomagnetic storm activity and 147 days with minor to severe storms. 290 MER cases occurred out 1014 days of minimal activity (28.6%) 133 MER cases out 497 days of unsettled activity (26.76%) 0.91(0.72-116), 78 MER cases out of 273 days of active activity (28.57%) 1.00(0.74-1.34), 25 MER cases out 109 days of minor storm (22.94%) 0.74(0.47-1.19) and 12 MER cases out of the 38 days of moderate to extreme storms (31.58%) 1.15(0.57-2.31) p-value 0.697.

Conclusion:
There was no statistically significant association with geomagnetic storms and the occurrence of large vessel stroke interventions taking into consideration a 48 hour lag effect. Comprehensive stroke center readiness is of utmost importance, but space weather forecasts are unlikely to be helpful in predicting LVO stroke cluster events.
Abstract TP55: Racial And Gender Disparities In Patients Undergoing Mechanical Thrombectomy At A Comprehensive Stroke Center
Authors: Duru Olivia , Eaton Ryan , Heaton Sharon , Powers Ciaran
Published: February 2023

Introduction:
Mechanical thrombectomy is the standard of care for acute ischemic stroke for select patients with large vessel occlusion (LVO). Racial and gender disparities exist in the incidence, morbidity, and mortality related to stroke. Furthermore, racial disparities in the utilization of thrombectomy have been previously identified. However, disparities in the utilization of thrombectomy in a single center with a standardized patient selection protocol have not been described.

Methods:
Using the American Heart Association Quality Improvement Programs Registry, we retrospectively reviewed the records of 1,143 patients with LVO between December 1, 2014, and May 31, 2021. Patient records were assessed for demographic data, stroke risk factors, process metrics, and success of thrombectomy. A Pearson’s Chi-Squared and an Independent two-sample T-test were used to determine significance.

Results:
Of the 1,143 LVO patients, 50.4% were female, 49.6% were male, 84.3% were white, 15.7% were nonwhite. Males were more likely to have diabetes compared to females (22.8% versus 17.9%; p=0.044). There were no significant differences based on race for stroke risk factors including diabetes and atrial fibrillation. Patient selection for thrombectomy was determined by a protocol agnostic to gender and race. Female patients were more likely to undergo thrombectomy compared to males (62.4% versus 48.9%; p<0.001). White patients were more likely to undergo thrombectomy compared to nonwhites (58.7% versus 39.7%; p<0.001). White patients were more likely to have a shorter interval between their last known well (LKW) to arrival (454 minutes versus 533 minutes; p=0.008) despite the fact our nonwhite patients were more likely to originate from our local county (58.1% versus 8.3%; p<0.001).

Conclusions:
In our analysis of LVO patients, female patients and white patients were more likely to undergo mechanical thrombectomy. The higher incidence of diabetes in males may have resulted in the patients presenting with a larger core infarct, making them ineligible for thrombectomy. Further investigation with data from multiple centers will be necessary to validate these findings and identify strategies for improving utilization of thrombectomy.
Abstract TP58: Dedicated Stroke Emergency Department APP/Physician Team Improves Door To Provider Times In A Comprehensive Stroke Center
Authors: Spatuzzi Janese , Shand Daniel , Deline Christopher J
Published: February 2023

Background:
Stroke is the leading cause of disability in the US, yet best standard practices for acute stroke care even among premier hospitals in the US varies. The AHA/ASA Get with the Guidelines (GWTG) program set out to create standard metrics to reduce this variation between hospitals. One such measure is the Door to Provider time, with a goal of 10 minutes or less. This goal can be difficult to achieve in large, high volume, Emergency Departments with multiple providers present at a given time. Specialized care has been shown to improve patient outcomes. We set out to create a simple yet effective process improvement of creating a dedicated ED APP/Physician team for each shift to achieve this goal.

Methods:
Starting in January 2020, a NIHSS trained APP was dedicated to provide assessments of all potential stroke patients upon arrival to the emergency department for a particular shift with a supervising attending ED physician, who also provided backup in situations of concurrent cases. The APP was assigned a phone each shift that can be notified by medical control for any EMS pre arrival stroke notifications and by the triage clinician for ambulatory arrivals. Data was collected starting on January 15
th
2020 for each “Stroke Alert” page and the Door to Provider time was calculated based on documentation in the Emergency Department timeline. From January 15
th
2020 to March 31
st
2022, 2,410 patients were evaluated.

Results:
The Door to Provider time goal was met greater than 80% of the time.

Conclusion:
Phase III of Target: Stroke sets challenging time goals for the prompt evaluation and treatment of patients with acute ischemic stroke with an ultimate objective of improved patient outcomes. Through the simple implementation of a dedicated NIHSS trained ED APP and Physician provider for each shift in our high volume, community based Emergency department, we were able to improve and sustain our door to provider times. These process improvement outcomes persisted through the COVID 19 pandemic!
Abstract TP59: Prehospital Identification Of Acute Ischaemic Stroke With Large Vessel Occlusion
Authors: Leto Nedim , Bjorshol Conrad A , Kurz Martin , Østerås Øyvind , Fromm Annette , Lindner Thomas
Published: February 2023

Background:
The prehospital stroke scale B-FAST (Gaze deviation, Face paresis, Arm weakness, Visual loss and Speech disruptions ) was implemented in the Emergency Medical Services (EMS) in the Western Norway Regional Health Trust (1,1 million catchment population; eight primary stroke centres (PSC) ; two comprehensive stroke centres (CSC)) in 2019 to detect acute ischaemic stroke (AIS) patients with large vessel occlusion (LVO). Prehospital presence of gaze deviation (B-symptom)and at least one FAST symptom, may lead to PSC bypass and proceed directly to a CSC. The aim of the study was to investigate the sensitivity of the B-FAST scale detecting LVO in the prehospital setting.

Methods:
Retrospective study including patients with at least one B-FAST symptom at EMS arrival. We obtained patient data from all code red stroke dispatches from Emergency Medical Communication Centres (EMCC) and local endovascular treatment (EVT) registries in the period August-December 2020. Variables collected were clinical features, CT examination and reperfusion treatment. Definition of prehospital positive B-FAST was presence of Gaze deviation (B-symptom)and at least one FAST symptom at EMS arrival.

Results:
We collected data on 643 patients, 59 were diagnosed with a LVO stroke at hospital arrival. In the LVO group, 7 of 59 patients presented with prehospital positive B-FAST, resulting in a sensitivity of 12 %. EVT was performed in 38/59 (64%) cases. Two patients were false negative and positive predictive value was 78%. Specificity was 99% and negative predictive value 83%. Median transfer delay for patients initially admitted to a PSC before transfer to a CSC, was 130 min (IQR 60-167 min).

Conclusion:
The use of B-FAST by EMS personnel for identification of AIS patients with LVO has a low sensitivity, but presence of gaze deviation predicts LVO stroke with high certainty.
Abstract TP60: Intravenous Thrombolytic Administration For Acute Ischemic Stroke Is Associated With Decreased 30-day Readmission As Well As 1-year Mortality And Recurrent Stroke
Authors: Nguyen-Huynh Mai N , Alexander Janet , Lee Catherine , Zrelak Patricia A , Klingman Jeff
Published: February 2023

Background:
Reducing 30-day readmission can potentially improve quality of stroke care. We investigated factors associated with 30-day readmission,1-year mortality and stroke recurrence post-ischemic stroke.

Methods:
Cohort included primary ischemic stroke discharges 1/1/2015 to 3/31/2021 from a large racial-ethnically diverse integrated healthcare delivery system. Assessment included demographics, comorbidity, NIHSS, IV thrombolytic, thrombectomy, hospital complications, and mRS score at discharge. Multivariate analysis was done to determine predictors for 30-day readmission, 1-year mortality and stroke recurrence.

Results:
Of 13,053 ischemic stroke patients,1,790 (13.7%) were readmitted within 30 days. The median time to readmission was 10 days (IQR 4-19). Readmission was most-commonly stroke-related (21.6%). Being older, having higher initial NIHSS or co-morbidity score or more hospital complications, not receiving IV thrombolysis, and being more disabled at discharged were seen more often among those who were readmitted (Table). In multivariate analysis, being older, having higher initial NIHSS and co-morbidity score were associated with higher odds of being readmitted by 30-day and having higher mortality and stroke recurrence at 1-year. Adjusted odds for stroke recurrence were elevated for black patients. Being readmitted by 30-day also predicted greater odds of 1-year stroke recurrence and 1-year mortality. On the other hand, receiving IV thrombolysis was associated with significantly less odds of being readmitted at 30-day (OR=0.74; 95% CI = 0.59 - 0.93) and less stroke recurrence (OR=0.75; 95% CI =0.64 - 0.87) and less mortality at 1-year (OR=0.57; 95% CI = 0.42 - 0.76).

Conclusions:
A number of factors predicted 30-day readmission as well as 1-year stroke recurrence and mortality. Receiving IV thrombolytic for acute stroke was strongly associated with lower odds of developing bad outcomes.
Abstract TP65: An Automated Algorithm For The Nih Stroke Scale Assessment
Authors: Andrade Joao B , Camilo Millene , Domingues Renan , Kuster Gustavo W , Pacheco Evelyn , Frigini Tiago , Vieira Neto Ronan J , Fornazari Ana , Ferraz Hanna , Lacerda Cassio , Gagliardi Vivian , Viana Patricia , Pellegrino Mateus , Zaveri Daniel , Sampaio Silva Gisele
Published: February 2023

The NIH Stroke Scale (NIHSS) is widely adopted in clinical practice. Despite being originally designed for research use, the NIHSS is a valued resource for communication and prognostication, and it is useful for the decision-making process regarding reperfusion therapies and prophylaxis. However, its assessment can be laborious and complex among even certified healthcare providers. In the context of increasing telemedicine use, an accurate assessment of the NIHSS may be crucial in acute stroke management

We aimed to create and validate an automated tool for the NIHSS (SPOKES) in a national telemedicine service.

A board of five certified vascular neurologists created an NIHSS algorithm based on a tree decision, including tips and hints in the main questions and auxiliary boxes. We randomized 22 spoke hospitals using an automated tool to invite emergency physicians not certified in the NIHSS to use or not the SPOKES. NIHSS-certified and blinded neurologists from a hub hospital performed a double-check of each item of the NIHSS.

From June to August 2022, we included 144 cases from 10 spoke hospitals. Our algorithm was fully adopted in 27 cases (19%). The median of reported NIHSS was 3 [1, 5] and 3 [2, 7] points among users and non-users, p=0.38. The general difference between the reported and the double-checked score was 0 [0, 1] points – there was no difference between those who used or did not the SPOKES (p=0.12). A complete concordant score was achieved at 66.7% (n=18/27) and 45.3% (n=53/117), χ
2
=0.036, among users and non-users, respectively. In a bivariate regression analysis, the SPOKES increased the chance of complete agreement [OR 2.4, 95%CI 1-5.8, p=0.049]. There was no difference regarding discrepant scores (≥4 points), χ
2
=0.46. Among SPOKES cases, treatment with tPA was indicated in 11.1%, versus 12.7% among non-users (p=0.59).

Despite the small number of included cases, our algorithm seems to be a promising tool for the NIHSS assessment in a national telemedicine service, increasing the chance of a complete agreement with certified neurologists. The tool is free and available at
www.spokes-nihss.com
Abstract TP66: Trends In Alcohol Abuse In Patients With Intracerebral Hemorrhage: A 20-year Analysis Of The Nationwide Inpatient Sample
Authors: Downes Margaret H , Hardigan Trevor , Rossitto Christina , Vasan Vikram , Odland Ian , Schuldt Braxton R , Devarajan Alex , Fifi Johanna T , Kellner Christopher P , Majidi Shahram
Published: February 2023

Introduction:
While chronic alcohol (EtOH) abuse has long been considered a risk factor for several cardiovascular disorders including ischemic stroke, the relationship between intracerebral hemorrhage (ICH) and EtOH abuse is less known.

Objective:
To characterize ICH patients with EtOH abuse and examine the effects of EtOH abuse on in-hospital outcomes over 20 years.

Methods:
A query of the 2000-2019 National Inpatient Sample was performed for patients admitted with ICH (ICD9 431, 432.9, ICD-10 I61, I62.9). Demographics, comorbidities, and outcomes were identified. Univariate analysis with t-tests or chi-square performed as appropriate. A 1:1 nearest neighbor propensity score matched cohort was generated. Variables with standardized mean differences >0.1 used in multivariate regression to generate adjusted odds ratios (AOR)/β-coefficients for EtOH abuse on outcomes. Significance set at an alpha level of <0.001. All analysis performed in R version 4.1.3.

Results:
In total, 2,000,868 patients with ICH were identified; 106,987 (5.3%) abused EtOH. EtOH abuse patients had higher Elixhauser Comorbidity Score (12.95 ± 10.51 vs. 10.28 ± 8.98; p<0.001) and a non-significantly lower NIH Stroke Score (11.0 ± 8.69 vs. 11.34 ± 9.53; p >0.001). Patients with EtOH abuse were more likely to be male, younger, smokers, on Medicaid, be in the 0-25% percentile median income bracket, and have atrial fibrillation, hyperlipidemia, diabetes, and seizures (all p<0.001). Patients with EtOH abuse had less in-hospital mortality, more discharge home or short term hospital, longer hospital stays and more hospital charges (all p<0.001), but after propensity matching and regression analysis these differences were no longer significant.

Conclusion:
This 20 year nationally representative propensity matched analysis of patients with ICH demonstrates that concomitant EtOH does not significantly worsen in-hospital outcomes despite a higher association of other comorbidities.
Abstract TP67: Addressing Social Determinants Of Health In An Urban Safety Net Hospital A Quality Improvement Initiative
Authors: Onuigbo Chiamaka , Patel Harsh , Porrey Kelly , Frankel Michael R , Navalkele Digvijaya
Published: February 2023

Introduction:
Over 10% of stroke survivors have a recurrent stroke, and studies indicate that Black people have a higher risk of stroke recurrence. Social Determinants of Health (SDoH) are associated with a high incidence of stroke, and there is emerging data on recurrence. Grady Memorial Hospital serves this vulnerable urban population at high risk of first and recurrent stroke. We sought to determine the prevalence of SDoH in our clinic population and address these unmet needs to reduce disparities.

Methods:
We implemented SDoH screening in the stroke clinic by training two medical assistants to fill out the SDoH questionnaire during patient check-in. Screening results were checked by the fellows/attending during the clinic visit. Social worker consultation was sought for unmet social needs. Data was collected in a prospectively maintained stroke clinic registry.

Results:
There were 131 patients seen between October 2021 and February 2022 in the stroke clinic. Of those, 108 patients (82%) were screened for unmet SDoH needs (financial, transportation, and food insecurity). Of the screened, 81% were black, mean age was 55 years, 51% were male, and 59% were from economically at-risk or distressed communities. The mean duration from stroke onset to clinic visit was 12 months. Fifty-eight of the screened patients had at least one unmet need (54%), 30 had none (28%), and 20 were unknown (19%). Eighty-one percent (47/58) of patients with unmet needs had BP ≥130/80 (Odds ratio 2.47 CI 0.91-6.66, p =0.07). Most patients had financial insecurity (74%), followed by transportation needs (55%) and food insecurity (50%). Of the patients with unmet needs, 59% (n=34/58) reside in economically at-risk or distressed communities. 55% (32/58) of patients received resources to address these needs during the clinic visit.

Conclusions:
We found a high prevalence of unmet social needs in our stroke population, and the needs persisted for at least a year post-stroke. Screening and addressing unmet social needs should be incorporated as a routine follow-up post-stroke care. Systematic ways of assessing SDoH to address their effects on stroke recurrence and recovery should be done in larger studies.
Abstract TP81: Healthcare Disparities For Thrombolysis In Patients Presenting With Stroke-like Symptoms At A Comprehensive Stroke Center
Authors: Ray Debarti , Kim Ben , Fournier Lauren E , Graybeal Dion , McAlpine Candace , Rasmussen Jennifer
Published: February 2023

Background:
Stroke is a leading cause of death and disability. Early presentation allows clinicians to use tPA for acute stroke therapy to improve outcomes. However, healthcare disparities among different racial/ethnic and gender groups remain a limitation for uniform access to acute stroke therapy. We investigated if such gender and racial disparity exist in tPA administration at a large community comprehensive stroke center (CSC).

Methods:
Retrospective analysis of a prospective cohort of patients was conducted of patient with acute stroke symptoms who presented to a CSC between May 2018 and May 2022. Demographics, time from last known normal (LKN), rate of tPA administration and door to needle time (DTN) was calculated. Univariate analysis between groups was performed using one-way ANOVA for mean, Kruskal-Wallis test for median and p-value <0.05 was considered significant.

Results:
Total number of patients presenting to our CSC during the study period with stroke like symptoms was 3901. Of this index cohort, 401 (10.2%) were administered tPA - 207 (51.6%) women and 194 (48.3%) men. Women were significantly older [67.5 ± 15.1 years compared to men, 62.6 ± 13.3 years (p=0.027)]. Average time of LKN to arrival was 124 ± 3.8 min for women and 130 ± 4.9 min for men (p=0.298). Black women’s DTN was longer compared to white women
(
50.9 ± 3.15 min v. 41.5 ± 2.07 min, p=0. 0103). However, proportion of Black women receiving tPA did not differ from white women [87/770 (11.3%) v. 113/1041 (10.9%), p=0.824]. Race disparity was noted among Black men compared to white men for tPA administration [64/798 (8.0%) v 119/1226 (9.7%), p=0.018]. No gender or racial disparity was noted among tPA recipients regarding mRS at discharge [white men v. white women v. Black men v. Black women - 2 (IQR 1,4) v. 3 (IQR 1,4) v. 3 (IQR 1,4) v. 3 (IQR 1,4), p=0.211].

Conclusions:
At a large volume, urban, non-academic comprehensive stroke center, overall gender, or racial factors were similar for discharge outcome. However, a delay in tPA administration among Black women and lower incidence of tPA administration in Black men compared to their respective white counterparts need to be validated in larger registries.
Abstract TP84: Ring-like Pattern On Post-EVT MRI Is A Marker Of Perihematomal Edema
Authors: Hsia Amie W , Luby Marie L , Lomahan Carolyn , Davis Rachel , Lynch John K , Adil Malik , Burton Shannon P , Kim Yongwoo , Craft Veronica , Uche Victoria , Cabatbat Rainier Michael , Thomas Leila , Afzal Mariam , Latour Lawrence
Published: February 2023

Introduction:
Perihematomal edema is a consequence of primary intracerebral hemorrhage. On diffusion MRI, a corresponding heterogenous pattern of hypo- and hyper-intensity is visible on apparent diffusion coefficient (ADC), suggesting both cytotoxic and vasogenic edema. Analogously, endovascular therapy (EVT) for ischemic stroke can result in hemorrhagic transformation (HT) and a concomitant ring-like pattern, or “Rings” of mixed intensity on ADC. The objective of this study is to describe this pattern of secondary injury early after EVT.

Methods:
Patients were included if they consented to the prospective Natural History of Stroke GUARDS study from April 2018 to February 2022, were treated with EVT for anterior circulation LVO, achieved TICI 2b/3 reperfusion, and had early MRI, ~2h post-EVT. Two independent readers measured early and 24h DWI lesion volumes and 5d FLAIR lesion volumes using a semi-automated validated approach. Presence of any HT on GRE and Rings on ADC (Figure) on early, 24h, and 5d MRI were read independently by multiple readers who then reached consensus. The relationship of Rings with HT and lesion volume was explored.

Results:
Eighty-nine patients were included with median age 64y, 55% female, median admit NIHSS 18, 64% M1 LVO, and 47% IV tPA. On early MRI, 14 (16%) patients had Rings, 12 (86%) of whom also had HT (p<0.001). At 24h, 42 (50%) patients had Rings with 33 (79%) also having HT (p<0.001). There was a strong association between presence of Rings at 24h and 5d-FLAIR lesion volume, 56mL vs. 24mL in patients with vs. without Rings (p=0.002).

Conclusions:
Rings on ADC was seen in half of patients 24h post-EVT and appears to reflect peri-lesion edema associated with hemorrhagic transformation. This imaging marker was associated with larger lesion volumes at 5 days and may be able to serve as a target for adjunctive therapy post-EVT to mitigate edema formation.
Abstract TP85: Clinical And Imaging Biomarkers Of Ageing And Stroke Severity, And Their Interaction With Clinical Outcomes
Authors: Kis Balázs , Neuhaus Ain , Harston George , Carone Davide , Joly Olivier , Gerry Stephen , Chadaide Zoltan , Pánczél András , Czifrus Eszter , Csike Viktória , Surányi Ágnes , Szikora Istvan , Eross Loránd
Published: February 2023

Outcomes following endovascular thrombectomy (EVT) for large vessel occlusion stroke remain variable. Clinical predictors include presenting NIHSS and age, surrogate metrics of stroke severity and pre-stroke brain health, respectively. Imaging biomarkers can also predict outcome, but prognostic models typically only include biomarkers of acute stroke severity. This study aimed at exploring how incorporating both imaging biomarkers of stroke severity and brain frailty, automatically derived from routine imaging, impacts outcome prediction following successful EVT. In this single-center retrospective study of 215 patients presenting with anterior circulation stroke, we evaluated prognostic significance of automated analysis outputs from e-Stroke. Acute ischemic volume (AIV) and e-ASPECTS were used to define stroke severity. Cerebral atrophy was used as a marker of brain frailty. Models incorporating imaging biomarkers, clinical features, procedural factors, and combinations of these were evaluated using multivariate regression models predicting mRS 0-2 at 30 and 90-days, NIHSS improvement, mortality and sICH. Incorporation of brain atrophy into models negated the effect of age on patient outcome. The interaction of stroke severity with age was similar to that of infarct volume and brain atrophy. Models incorporating age, presenting NIHSS, AIV, atrophy, reperfusion status and time to recanalization outperformed clinical models at predicting NIHSS improvement (ROC AUC 0.81 and 0.57, respectively) and 90-day mRS. Combinations of imaging and clinical features were superior for predicting any outcome compared with clinical or imaging features in isolation. Models incorporating automated image analysis of acute infarct volume and atrophy outperform models based solely on clinical characteristics for predicting short- and long-term outcome following EVT. Atrophy as a marker of brain frailty is associated with poorer long-term outcomes and negates the effect of age in multivariate models. AIV tempers the effect of intervention on early neurological improvement. Better understanding the relationship between stroke severity and baseline health status may improve patient selection strategies for reperfusion therapies.
Abstract TP87: Predictors Of Diffusion-weighted Imaging Lesion Burden In Patients After Minimally Invasive Surgery For Intracerebral Hemorrhage
Authors: Rossitto Christina P , Vasan Vikram , Downes Margaret H , Yildiz Sema , Liang John , Schupper Alexander J , Hardigan Trevor , Chapman Emily K , Mocco J , Kellner Christopher P
Published: February 2023

Introduction:
The etiology of diffusion-weighted imaging (DWI) lesions in patients after minimally invasive surgery (MIS) for acute intracerebral hemorrhage (ICH) remains unclear.

Methods:
Postoperative brain MRIs of patients with spontaneous ICH from 2016-2021 who underwent imaging within one month of MIS were reviewed. DWI lesions were quantified. Lesions within 10 mm of the hematoma were excluded. Siderosis and microbleeds were identified. Leukoaraiosis was quantified using the Fazekas score. Univariate analyses were conducted to determine predictors of DWI lesion burden, and variables with P≤0.1 were included in multivariate analyses.

Results:
DWI lesions were present in 84 (49%) postoperative MRIs. The average number of DWI lesions was 2.11 (range 0-74, SD 6.50). Factors associated with DWI burden in univariate analyses included increased presenting systolic blood pressure (SBP) (P=0.003), Fazekas score (P=0.004), delta SBP on day of admission (P=0.034), preoperative angiogram (P=0.062), microbleeds on MRI (P=0.065), increased presenting National Institutes of Health Stroke Score (P=0.066), presence of intraventricular hemorrhage (P=0.069), and decreased presenting Glasgow Coma Scale (P=0.076). Upon multivariate analysis, increased Fazekas score (OR 2.04, 95% CI 1.21-3.43, P=0.008), presenting SBP (OR 1.04, 95% CI 1.00-1.06, P=0.014), and preoperative angiogram (OR 10.35, 95% CI 1.44-74.36], P=0.020) were predictive of DWI burden.

Conclusions:
In this unique postoperative ICH cohort, white matter changes, presenting SBP, and preoperative angiogram predicted DWI lesion burden. Larger studies are needed to understand the implications of DWI burden after MIS for ICH recovery.
Abstract TP9: Examining Predictors Of Functional 90-day Outcome Among Stroke Patients With Active Cancer Receiving Endovascular Therapy
Authors: Pirahanchi Yasaman , McGraw Constance , Bartt Russell , Burrell Christian , Bar-Or David
Published: February 2023

Introduction:
Intraarterial therapy (IAT) is the standard of care for all AIS patients, even those with active cancer. However, there is little information on the characteristics that may contribute to a functional 90-day modified Rankin scale (mRS 0-2) score for AIS patients with active cancer undergoing IAT.

Methods:
This retrospective study included patients (age ≥ 18) admitted from 07/18-10/20 with AIS and were treated by IAT. AIS patients with large artery occlusion who had active cancer were identified. Baseline characteristics and outcomes were evaluated to determine predictors of a functional outcome at 90 days. Outcomes were also compared to those without active cancer during the same period. The receiver operating characteristic area under the curve (AUC) was used to determine optimal admission national institutes of health scores (NIHSS) to obtain a 90-day mRS of 0-2.

Results:
Of the 453 patients who received IAT, 12% had active cancer. Overall, patients were a majority male (50%), a median of 70 (60-81) years of age and had an admission NIHSS of 14 (7-20). Compared to patients without cancer, patients with cancer experienced significantly more thromboembolic events during their hospital stay (40% vs. 11%, p<0.001), but functional outcomes at 90-days were not different between groups. In active cancer patients, an admission NIHSS cut-off of 8.2 (AUC:0.72 (confidence interval (CI): 0.58-0.86), p=0.001) indicating strong fit, and experiencing less thromboembolic events, were significantly associated with functional independency at 90 days. However, the admission NIHSS cut-off for patients without cancer for predicting a functional outcome was 10.5 (AUC: 0.66 (CI: 0.60-.71), p<0.001), indicating moderate fit. Receiving intravenous tissue type plasminogen activator (IV-tPA) and successful reperfusion were other significant predictors of a functional outcome for non-cancer patients.

Conclusions:
In our population, using an NIHSS cut-off of 8.2 for patients with active cancer in determining who should receive IAT may increase the probability of a favorable 90-day outcome. An admission NIHSS of 10.5 was moderately associated with functional outcome at 90 days, in addition to successful reperfusion and receiving IV-tPA in non-cancer patients.
Abstract TP90: Lesion Topography Role On Functional Outcome Of Stroke Patients
Authors: Cavalcante Fabiano W , Konduri Praneeta , Terreros Nerea , Marquering Henk , Majoie Charles B
Published: February 2023

Background:
The anatomical site of ischemia in stroke patients might impact functional outcome and can be a relevant factor for prognosis and clinical decision.

Methods:
We included patients from the MR CLEAN stroke trial population who had an adequate 5-9-day control CT scan. The images were segmented and registered over two neuroanatomical atlases. Each anatomical region was classified as affected or spared based on the total amount of voxels in each region interpreted as ischemic on CT imaging. Analysis were conducted with a threshold level of 20% and 50% of the total voxels as a binary classification criteria for considering a brain area as affected by the ischemic core. Univariate and multivariate analysis were conducted to assess for relationships between specific brain regions involvement and worse functional outcome (defined by the 90-day mRS).

Results:
A total of 356 patients was included. The left dorsal striatum and left insular ribbon were significantly associated with worse outcomes after correction for the total lesion volume (p < 0,05). On a binary logistic model, no areas were significantly associated with worse outcome when a threshold of 20% was used. Both left and right dorsal striatum’s were significantly associated with worse outcome after adjustment for volume when a threshold of 50% was used.

Conclusion:
Some areas of the brain appear to have a higher impact on clinical outcomes for stroke patients. Areas related to motor function were strongly associated with the 90-day mRS when compared to other brain areas. The impact of a brain region on outcome also seems to depend on which hemisphere has been affected and on the extent to which the region that has ben involved in the ischemia.
Abstract TP92: Early Hyperacute Ion Dysregulation Following A Temporary Large Vessel Occlusion Stroke
Authors: Pushie Michael (Jake) , Sylvain Nicole , Hou Huishu , Kelly Michael E
Published: February 2023

Introduction:
Ion dysregulation is a hallmark of energy failure after onset of ischemic stroke. To better understand the nature of the ion concentration changes in the early hyperacute phase after stroke onset we have quantitatively imaged the trace element distribution in the stroke lesion territory after a 30-minute temporary large vessel occlusion stroke.

Methods:
A temporary large vessel occlusion stroke was generated with the middle cerebral artery occlusion (MCAO) mouse model (insertion of an occluding filament via the ECA) with reperfusion after 30 minutes (occluding filament withdrawn). C57BL/6 mice (5 per time point) were euthanized at 5-, 30-, 60-, 90-, and 120-minutes post reperfusion. Shams included all surgical procedures, however the occluding filament was withdrawn immediately after insertion. Heads were immediately frozen post mortem and sectioned for trace element mapping. Quantitative X-ray fluorescence microscopy was performed at the Stanford Synchrotron Radiation Lightsource.

Results:
Loss of potassium is observed throughout the affected tissue at all post-reperfusion time points, with most of the initial loss occurring in the 30-minutes prior to reperfusion. Loss of essential zinc began to be observed 1-hour post reperfusion. No significant elevations in chlorine or calcium were observed during the early hyperacute phase. At subsequent post reperfusion time points the lesion (as defined by diminished potassium) grew steadily for 90-minutes. After 90-minutes post reperfusion some lesions demonstrated a distinct pattern consistent with a central infarct core surrounded by an ischemic penumbra.

Conclusions:
At all early hyperacute time points the stroke lesion demonstrated on-going potassium dysregulation, despite reperfusion. The loss of potassium was a bulk phenomenon in the tissue. Potassium is essential for maintenance of neuronal membrane potential and therefore function. Restoration of normal blood flow is insufficient to protect the brain from the enduring reduction in vital potassium levels or expansion of the region of ion dysregulation. The lack of available potassium within the affected tissue may hinder recovering neuronal cells from restoring action potentials, even after tissue perfusion is restored.
Abstract TP94: Optimizing The Utilization Of Cardiac Computed Tomography Angiography Among Patients With Ischemic Stroke
Authors: Zhang Tony J , Patel Himanshu A , Kherani Danish , Bhavsar Riya , Karim Sanaa , Ramy Maya , Bhenderu Lokeshwar , Pan Alan P , Vahidy Farhaan S , McCane David , Chiu David , Volpi John J , Gadhia Rajan R , Garg Tanu
Published: February 2023

Background:
The current AHA guidelines recommend (class IIb) advanced cardiac imaging in embolic stroke of unknown source (ESUS). We aim to better characterize the role of cardiac CTA (cCTA) in the evaluation of stroke patients.

Method:
A retrospective review of stroke patients at a comprehensive stroke center, who had cCTA between 12/2016 and 11/2020 was conducted using institutional registries. Ischemic stroke patients with ESUS, cryptogenic (with ESUS as a competing etiology) and cardio-embolic etiologies were included. Only cardioembolic etiologies in which a suspicion of intracardiac thrombus with either a known diagnosis of atrial fibrillation or presence of LVAD were included. Cases with TIA, large vessel disease, small vessel disease, dissection or hemodynamic etiologies were excluded. TTE and cCTA results from all cases were reviewed for remarkable findings, most notably intracardiac thrombus, and analyzed if a change in anti-thrombotic therapy was directly attributable to cCTA results.

Results:
As per our criteria, 96 cases (Female 42.7%, Black 37.5%, Age mean: 63.7 years) were included, of whom 45 (46.9%) were ESUS, 21 (21.9%) were cryptogenic, and 30 (31.2%) were cardioembolic. cCTA revealed intracardiac thrombus in 5 (5.2%) cases, all with LA thrombus. Of these, 3 (60%) had escalation of anti-thrombotic therapy. Interestingly, in one patient who had both cMRI and cCTA imaging, the cMRI revealed an apical LV thrombus which was not detected on cCTA.

Conclusion:
In this retrospective analysis of 96 select stroke cases, escalation of anti-thrombotic therapy from anti-platelets to full dose anti-coagulation was indicated in 3 patients (3.1%) with addition of cCTA. Compared to a similar cohort of patients from the same institutional registry using cMRI as the advanced cardiac imaging modality, cCTA did not reveal any LV thrombi and even missed a case of LV thrombus seen on cMRI suggesting lower sensitivity for cCTA to detect LV thrombus. Further analysis of data is in process to determine the subset of stroke patients who would benefit the most from cCTA.
Abstract TP98: Deep Learning-based Automatic Ischemic Core Estimation Based On Non-contrastenhanced Computed Tomography
Authors: Nishi Hidehisa , tsuji hirofumi , Ishii Akira , Fuchigami Takuya , Tachibana Atsushi , Ito Hirotaka , Miyamoto Susumu
Published: February 2023

Background/Purpose:
With the spread of thrombus retrieval procedures, the demand for immediate diagnosis and severity assessment of ischemic stroke is increasing, but current standard method using ASPECTS is semi-quantitative, and has low consistency among physicians. We develop and validate the fully automatic machine learning-based ischemic core segmentation model based only on non-contrast-enhanced computed tomography (NCCT).

Materials and Methods:
This multicenter retrospective study included patients with anterior circulation acute ischemic stroke who received both CT and MRI before thrombolysis or recanalization treatment between 2013 to 2019. The ischemic core on CT was manually delineated referencing the DWI and ADC map. A deep learning-based ischemic core segmentation model was developed using the derivation cohort data from 3 institutions (n=313), and the model performance was validated on the external validation cohort data from 3 institutions (n=106).

Results:
On the validation cohort, the median time between CT and MRI was 18 min. The ischemic core volume calculated by the DL model was significantly correlated with the reference standard (Pearson r=0.91, p<.001). The correlation was significant both in early time window (<4.5hr from onset; Pearson r=0.91, p<.0.01) and the late time window (>4.5hr from onset; Pearson r=0.93, p<0.01). The median difference between model and reference standard was 4.7 mL (IQR, 0.8-12.4 mL). The DL model displayed high accuracy on discriminating large ischemic core (>70mL) with a sensitivity of 84.2%, specificity of 97.7%, and AUC of 0.91.

Conclusions:
A segmentation model of cerebral ischemic core volume of the anterior circulation based on NCCT using deep learning showed good correlation with the correct labels generated with reference to MRI.
Abstract TP99: Non-invasive Aortic Pulse Wave Velocity Is Related To Gold Standard Carotid-femoral Pulse Wave Velocity: Implications For Monitoring Large Artery Stiffness In The Clinic
Authors: Parr Shannon , Scheuermann Britton , Hammond Stephen , Ade Carl J
Published: February 2023

Introduction:
Aortic stiffness is an independent predictor of fatal stroke in both hypertensive populations and healthy subjects, but traditional monitoring methods have had difficulty being incorporated into routine practice. The gold standard, carotid-femoral pulse wave velocity (cfPWV), poses methodological challenges as this method bypasses the most distensible vessel, the proximal aorta. We propose a new method, aortic arch pulse wave velocity (aaPWV) assessed via ultrasound, which encompasses the proximal aorta and can be performed during standard cardiac echocardiography. We sought to determine if the two methods were related.

Methods:
We recruited 44 healthy volunteers (38.1y [SEM: 2.39], range 20-62y, 80% female) for this study. Both aaPWV and cfPWV were measured by the wave-foot method using a commercial Logic S8 Ultrasound system (GE Healthcare) with synchronous electrocardiogram. cfPWV was calculated by determining the time delay between the two vessels and dividing by the measured distance between the two sites. aaPWV was calculated by determining the time delay between onset of aortic ejection from the apical 5-chamber view and the arrival of the pulse wave at the start of descending aorta in the suprasternal view. Distance for aaPWV was estimated using regression equation from the literature.

Results:
Paired t-tests revealed cfPWV was significantly greater than aaPWV (5.98 ± 0.17m/s vs. 4.7 ± 0.29m/s; P<0.001). Pearson correlation revealed the two methods were related (r=0.35, P=0.01) and intraclass correlation coefficient revealed good agreement within and between raters (0.75, 0.85 respectively; 0.75-0.9 indicate good agreement).

Conclusion:
We report that while aaPWV and cfPWV are correlated, significant differences exist, which was expected given the proximal segment is the most elastic portion of the aorta. The findings from this study suggest aaPWV could be a more feasible method to measure large artery stiffness in routinely in the clinic, but future studies are needed to determine if aaPWV is similarly predictive of adverse cardiovascular outcomes.