bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 10: Does the use of CT perfusion (CTP) increase treatment rate of endovascular thrombectomy (EVT) in acute ischemic stroke patients?
Authors: Marginean Horia , Stuchiner Tamela , Hallak Patrice , Tarpley Jason
Published: January 2025

Introduction:
CTP is used to distinguish core infarct from penumbral tissue in the 6-24 hour time window from last known well time (LKW). In addition, routine use of CTP inside of 6 hours may increase the sensitivity of detecting medium vessel occlusion (MeVO) as compared with CTA alone. Therefore, some centers apply a strategy of using CTP/CTA routinely in the first 6 hours from LKW while others reserve CTP for the 6-24 hour delayed time window. We hypothesized that use of CTP/CTA inside of 6 hours from LKW is associated with increased EVT especially for MeVO.

Methods:
This is a retrospective analysis of acute ischemic stroke (AIS) patients from a multi-state stroke registry between Jan 2018 and Mar 2024 who presented within 6 hours of LKW. The incidence of EVT by triage imaging modality (CTA or CTA/CTP) was analyzed overall and also by occlusion location (Large vessel occlusion (LVO), MeVO) through linear mixed models (LMM). Multivariable models were used to adjust for confounding factors. A two-tailed p value of <0.05 was considered statistically significant. Statistical analyses were performed using the statistical software R (version 4.2.3).

Results:
Of the 13,778 AIS patients analyzed, 43% were triaged with CTP/CTA and CTA alone was used for 57%. The unadjusted EVT treatment rate was 9.8% in patients triaged with CTA alone and 22% for patients triaged with CTP/CTA. LMMs adjusted for age at diagnosis, sex, race and ethnicity, NIHSS at admit and comorbidities show a higher statistically significant likelihood of receiving EVT in the CTA/CTP triaged patients (OR 1.6, 95%CI 1.3 to 1.8, p <0.001). For LVO, there was no difference in the likelihood of receiving EVT in the CTA/CTP triaged patients (OR 1.3, 95%CI 0.7 to 2.3, p = .4). However, for MeVO there was a higher likelihood of receiving EVT in the CTA/CTP triaged patients (OR 3.2, 95%CI 2.0 to 5.0, p <0.001) (
Fig 1
)

Conclusions:
The results here show that in a large system of stroke hospitals that AIS patients presenting within 6 hours of LKWT who received CTP/CTA were more likely to undergo EVT than those who received CTA alone. This increased utilization of EVT was accounted for by increased EVT for MEVO but not for LVO. The increased utilization of EVT in MEVO may reflect increased sensitivity of detecting MeVO with the addition of CTP. If MEVO EVT treatment proves effective in ongoing randomized clinical trials, our data argue for more routine use of CTP as a “MEVO detector” in the early time window.
Abstract 13: Intravenous Tirofiban as An Adjunct to Endovascular Therapy for Posterior Circulation Strokes with Tandem Lesions: One-Year Outcomes
Authors: Doheim Mohamed , Li Wei , Zi Wenjie , Qiu Zhongming , Han Zhongkui , Chen Zhonglun , Zhao Zhenqiang , Chen Zhibin , Al-Bayati Alhamza , Sun Wen , Nogueira Raul
Published: January 2025

Background:
The effectiveness and safety of intravenous Tirofiban as an adjunct to endovascular therapy (EVT) in posterior circulation patients with tandem lesions (PCTL) remain uncertain.

Methods:
This study utilized individual patient data pooled from two multicenter observational studies: the BASILAR and the PERSIST registries. We included patients with acute ischemic stroke due to PCTLs who were treated with EVT. The patients were divided into two groups based on whether they received adjunctive intravenous Tirofiban therapy or not. The primary efficacy outcome was favorable functional outcome, defined as modified Rankin Scale (mRS) scores of 0-3 at one year. Secondary outcomes included safety assessments, such as rates of symptomatic intracerebral hemorrhage (sICH), early neurological deterioration (defined as a decline in National Institutes of Health Stroke Scale [NIHSS] score by ≥4 points within 72h), and all-cause mortality at one year. We also evaluated procedural outcomes, including successful reperfusion, defined as modified Thrombolysis in Cerebral Infarction (mTICI) grade 2b-3, and complete reperfusion, defined as mTICI 3.

Results:
Among 210 patients treated with EVT (126 Tirofiban, 84 Non-Tirofiban), successful reperfusion (mTICI 2b-3) was achieved in 109 (86.5%) Tirofiban patients versus 64 (76.2%) non-Tirofiban patients (Adjusted OR 1.75, 95%CI [0.76-4.03], P=0.19). Complete reperfusion (mTICI 3) was achieved in 74 (58.7%) Tirofiban patients versus 36 (42.9%) non-Tirofiban patients (Adjusted OR 2.08, 95%CI [1.04-4.14], P=0.04). Rates of sICH were 6 (4.8%) in the Tirofiban group versus 9 (10.7%) in the non-Tirofiban group (Adjusted OR 0.24, 95%CI [0.04-1.36], P=0.11). Early neurological deterioration occurred in 18 (14.3%) Tirofiban patients versus 32 (38.1%) non-Tirofiban patients (Adjusted OR 0.20, 95%CI [0.09-0.46], P<0.001). One-year mRS 0-3 was achieved in 48/119 (40.3%) Tirofiban patients versus 24/82 (29.3%) non-Tirofiban patients (Adjusted OR 5.38, 95%CI [2.21-13.06], P<0.001). One-year mortality was 45/119 (37.8%) in the Tirofiban group versus 43/82 (52.4%) in the non-Tirofiban group (Adjusted OR 0.26, 95%CI [0.12-0.59], P=0.001).

Conclusion:
Intravenous Tirofiban as an adjunct to EVT may improve long-term functional outcomes in acute ischemic stroke patients due to PCTLs without significantly increasing the risk of hemorrhagic complications. Further prospective studies are warranted to validate these findings.
Abstract 19: Dental flossing may lower the risk for incident ischemic stroke, cardioembolic stroke subtype and AF
Authors: Sen Souvik , Marchesan Julie , Wood Stefanie , Titus Ryan , Moss Kevin , Alonso Alvaro , Soliman Elsayed , Magnani Jared , Johansen Michelle , Lakshminarayan Kamakshi , Rosamond Wayne , Beck James
Published: January 2025

Introduction:
Prior studies have shown the association between oral infection, incident stroke and atrial fibrillation (AF) a cause of cardioembolic stroke. However, the impact of preventative oral behavior such as dental flossing on stroke, cardioembolic stroke and AF are unknown. The relationship between flossing incident stroke, stroke subtypes and AF was tested in the Atherosclerosis Risk in Communities (ARIC) cohort study.

Methods:
In the ARIC study, home use of flossing was assessed through a structured questionnaire in visit 4 along with assessment of covariates including age, gender, race-center, hypertension, diabetes, hyperlipidemia, smoking, body mass index, education-level, regular brushing and regular dental care utilization . Outcomes were compared across index subtypes (infarction: thrombotic, cardioembolic, and lacunar strokes) using Kaplan-Meier analysis and Cox proportional hazards regression, adjusting hazards ratio (HR) for all the above covariates along with 95% confidence interval (CI).

Results:
In the ARIC study, 6278 dentate participants, without a prior history of stroke and 6108 without prior AF were followed for incident ischemic stroke, stroke subtypes and AF over a 25-year period. Of them 65% (N=4092 in stroke-free cohort and 4050 in AF-free cohort) reported flossing. During the follow-up period,434 were identified as having strokes, of whom 147 thrombotic, 97 cardioembolic and 95 lacunar subtypes. A total of 1291 (20%) participants were noted to have incident AF. The individuals reporting dental flossing had a lower rate of incident ischemic stroke, cardioembolic stroke and AF (Kaplan-Meier curves below). Dental flossing was significantly associated with a lower risk of ischemic stroke (adjusted HR, 0.78; 95% CI, 0.63-0.96), cardioembolic stroke subtype (adjusted HR, 0.56; 95 CI, 0.36-0.87) and AF ( adjusted HR, 0.88; 95% CI, 0.78-1.00), but not thrombotic (adjusted HR, 0.91; 95% CI, 0.63-1.32) or lacunar stroke (adjusted HR 1.09; 95% CI 0.68-1.76).

Conclusion:
Those reporting dental flossing have a lower risk for incident ischemic stroke, driven by cardioembolic stroke subtype and AF. The associated lower risks are independent of oral care/behavior measures such as regular brushing and regular dental care utilization, suggesting it may be a key behavior modification to emphasize in stroke risk reduction.
Abstract 27: The Brain-behaviour Mechanisms of Impaired Linguistic and Cognitive Function Impairments in Stroke Patients with Aphasia
Authors: Siqi Li , Yuan Zinan , Li Yuexiu , Liu Yang , Zhang Yumei
Published: January 2025

Introduction:
The combination of verbal and non-verbal cognitive dysfunction in post-stroke aphasia (PSA) patients may ultimately affect social interactions. However, the underlying neural mechanisms of both verbal and non-verbal cognitive impairment remain unclear. This study aimed to investigate the activity and functional abnormalities of local and remote brain regions and their relationship with cognitive behaviour, to provide more effective guidance in future clinical therapy.

Methods:
We recruited 46 PSA patients and 40 normal controls(NCs) matched for general characteristics in this study and evaluated their verbal and non-verbal cognitive functions. Functional magnetic resonance imaging(fMRI) was used to examine the fractional amplitude of low-frequency fluctuations(fALFF), regional homogeneity(ReHo), and functional connectivity(FC) in PSA patients. Independent two-sample t-tests were used to identify differences in these measures between two groups. Moreover, partial correlation analyses were performed to determine the correlation between FC from the affected brain regions and language and cognitive performance in PSA patients.

Results:
This study revealed that PSA patients presented significantly lower fALFF and ReHo values in right cerebellum superior (CRBL.Superior.R), left thalamus(THA.L), and left middle frontal gyrus(MFG.L). Moreover, the FC in the MFG.L-left inferior frontal gyrus, orbital part was significantly lower among PSA patients and was positively correlated with language and cognitive performance(p< 0.05). The CRBL. Superior. R-left caudate nucleus and right lenticular nucleus FC were also decreased and were associated with cognitive function(p< 0.05). In addition, PSA patients were further divided into fluent and nonfluent groups. The results revealed that nonfluent patients performed worse in verbal and non-verbal cognitive performance(p< 0.05) and had weaker performance in the THA.L and left supplementary motor area FC(p< 0.001).

Conclusions:
This study provides new evidence that abnormal neural activity and functional connectivity within specific brain regions may play crucial roles in language and cognitive processing. The underlying mechanisms of impaired linguistic function accompanied by decline in cognition may be a partial overlap between language and cognitive-related brain networks. In future, combining cognitive and linguistic functions and designing a comprehensive treatment plan will be the focus of rehabilitation.
Abstract 35: Impact of Artificial Intelligence Imaging Decision Support Software on Treatment of Acute Ischemic Stroke in England
Authors: Nagaratnam Kiruba , Neuhaus Ain , Epton Matthew , Marriott Tracey , Woodhead Zoe , Fernandez Claire , Ford Gary , Harston George
Published: January 2025

Introduction:
AI imaging decision support software is recommended by UK and USA stroke guidelines to facilitate identification and transfer of stroke patients eligible for endovascular therapy (EVT) but the impact on thrombectomy delivery is unclear. This prospective observational study evaluated the impact of Brainomix 360 Stroke software in four stroke networks (28 hospitals) in England’s National Health Service (NHS). The primary outcome was percentage of acute stroke patients receiving EVT (the EVT rate); door-in door-out (DIDO) times were assessed as a secondary outcome.

Methods:
Data were collected prospectively from the Sentinel Stroke National Audit Programme. The impact of Brainomix 360 Stroke software was assessed in two ways: comparison of EVT rates at the 28 evaluation sites and non-evaluation NHS sites before and after implementation (pre-implementation: Jan 2019-Feb 2020; post- : Jan 2022-Feb 2023); comparison of EVT rates and DIDO times at evaluation sites after implementation in patients for whom AI software was used and in those it was not. Multivariate regressions were used to evaluate whether AI use was a predictor of EVT or DIDO time, accounting for other clinical variables (e.g., age, NIHSS, day of week, time of day, time since onset).

Results:
The dataset included 71,327 patients from 28 evaluation hospitals. Figure 1 shows the change in EVT rates over time in evaluation (blue) and non-evaluation sites (yellow). EVT rate at evaluation sites increased from 2.3% pre-implementation to 4.6% post-implementation (p<.0001). By contrast, EVT rate at non-evaluation sites changed from 1.6% to 2.6% (p<.0001).

After implementation, cases that were reviewed with AI software support were more likely to receive EVT (5.9% vs 3.6%; OR=1.6 [95% CI:1.3-1.9, p<.0001). When limiting the analysis to cases admitted to primary stroke centres, the EVT rate was twice as high in cases reviewed with AI software (4.7% vs 2.2%; OR=2.3 [1.8-3.1], p<.0001). DIDO times were shorter for cases reviewed with AI software (median 127 vs. 192 minutes; p<.0001).

Conclusions:
This prospective study showed that use of AI imaging software was associated with a higher rate of EVT, both by comparing pre- vs. post-implementation data, as well as by comparing cases for whom AI software was versus was not used. Use of AI software was also associated with faster time to transfer. The results support guideline recommendations for AI software to be used in clinical practice.
Abstract TMP102: Title: Prediction of Post-Stroke AF in ESUS Patients is Enhanced by Combining Expert-Derived Predictors and Embedding of Full Diagnostic Codes using Pre-Trained Hypergraph Neural Networks
Authors: Wu Yuhua , Nahab Fadi , Ge Yi , Xie Yuzhang , Aboul-Nour Hassan , Yang Carl , Hu Xiao
Published: January 2025

Background:
Atrial Fibrillation (AF) occurs in about one-fourth of patients with Embolic Stroke of Undetermined Source (ESUS). Accurate prediction of post-stroke AF upon discharge from an index stroke admission informs a personalized post-stroke monitoring strategy of AF and interventions. While clinical risk scores predict AF, machine learning (ML) models have shown superior performance.

However, traditional ML approaches only use expert-derived predictors available in an electronic health record (EHR) and thus may miss variables that would potentially increase the accuracy of prediction.

Aims:
This study aims to enhance AF prediction by augmenting expert-derived predictors with an unbiased selection of full diagnostic codes and medication histories up to index strokes. Through embedding learning with hypergraph neural networks, we generate compact representations of high-dimensional data to improve prediction accuracy by capturing complex feature interactions.

Methods:
We analyzed data from 510 ESUS patients (55.3% female, mean age 61.4 years) from 2015 to 2023 at Emory Healthcare. We focus on experiments using a logistic regression (LR) model to predict AF from different sets of features. At baseline, we use 58 clinically motivated predictors, including comorbidities characterized by 17 ICD codes manually extracted based on literature, and 41 other features extracted from lab results, echocardiographic and ECG. To directly model the full history of comorbidities and medications, another baseline uses the full 1530 ICD codes plus the 41 other features (1571 in total). In contrast, the embedding method uses the full 1530 ICD codes to generate condensed, informative embedding vectors (32-dimensional), eventually getting 32+41=73 features. To generate the embedding, a hypergraph neural network was trained on a larger stroke cohort (n=7956) to model the interactions between the 1530 ICD codes. A nested cross-validation approach was employed within 5-fold splits, and ROC-AUC scores were recorded.

Result:
Among 510 ESUS patients, 107 (21.0%) developed AF (mean age 67.9 years, 57% female). We compared the performance of LR model with different features from ICD codes (Table 1). The results show that the learned 32-dim embedding vectors improves the prediction of post-ESUS AF.

Conclusion:
The embedding technique can significantly enhance predictive performance by integrating comprehensive medical information, maximizing the use of available data for improved outcomes.
Abstract TMP103: Associations Between Trust in Health Information Sources and Perceptions on the Modifiability of Stroke and Dementia Risks Using a U.S. Based Cohort
Authors: Ng Sharon , Senff Jasper , Maulik Meara , Tack Reinier , Tan Benjamin Yong Qiang , Pouwels Koen , Nunley Courtney , Shah Ostrowski Mark Jun , Pikula Aleksandra , Ibrahim Sarah , Towfighi Amytis , van Duijn Cornelia , Fricchione Gregory , Tanzi Rudolph , Yechoor Nirupama , Anderson Christopher , Rosand Jonathan , Singh Sanjula
Published: January 2025

Background:
Trust in healthcare information sources, specifically in healthcare professionals (HCPs) influences people’s health-related knowledge and behaviors. Epidemiological studies demonstrate that approximately 45% of dementia and 60% of stroke risks are attributable to modifiable risk factors. However, limited data exist on associations between trust levels in HCPs and people’s perceptions on the modifiability of dementia and stroke risks from a United States cohort.

Methods:
We developed a survey based on validated questionnaires and distributed it to a cohort of all U.S. states via the online Prolific platform in 2023. First, we described cohort characteristics and levels of trust in health information sources and mediums. We performed multivariable regression analyses between high trust of all HCPs (i.e. primary care physicians, specialists, and nurses) with the perceptions that dementia and stroke risks are modifiable, adjusting for age, sex assigned at birth, race/ethnicity, level of education, and status of knowing someone with stroke/dementia. Lastly, we performed hierarchal cluster analyses to characterize clusters of trust patterns and assessed their differences.

Results:
Our cohort consisted of 1,478 participants (52% females, median age 46 years [IQR:32-60], and 75% non-Hispanic Whites) with levels of trusts shown in
Figure 1
. Following multivariable regression analyses, participants who highly trusted all HCPs were statistically more likely to perceive that maintaining and changing health habits can reduce the risks of stroke or dementia (adjusted odds ratios presented in
Figure 2
). Lastly, three clusters of trust patterns emerged: (i) those who highly trust most sources (n=781), (ii) those who only trust official health sources (n=540) and (iii) those who have low trust of all sources (n=103) (
Figure 3
). Participants who have low trust of all sources (Cluster iii) were less likely to have a post-secondary degree (57% vs 67-71%, p=0.04) and to perceive that stroke (80% vs 93-94%, p<0.01) and dementia (65% vs 76-81%, P<0.01) risks are modifiable, compared to the other clusters.

Conclusion:
Our study identified highly trusted sources of health information, characterized trust patterns in a large U.S. cohort, and assessed their association with perceiving stroke/dementia risks as modifiable. This novel data could assist us in developing targeted interventions for risk reduction using trusted sources and mediums.
Abstract TMP109: Remote Ischemic Conditioning Treatment: A Study Report on Animal Stroke Model in Different Species, Sex, Age and Comorbidities from the Stroke Preclinical Assessment Network (SPAN)
Authors: Khan Mohammad B. , Kamat Pradip , Siddiqui Shahneela , Arbab Ali , Hess David , DHANDAPANI Krishnan , Bedirian Karni , Kodali Hanish , Diniz Marcio , Nagarkatti Karisma , Lamb Jessica , Lyden Patrick
Published: January 2025

Background:
The Stroke Preclinical Assessment Network (SPAN), a multi-center network consisting of a coordinating center and testing laboratories, was created to enhance the rigor of preclinical research, including testing of potential therapies in animals of different species, sex, age, and co-morbidities, with blinding and randomization. SPAN evaluated six potential therapies with the goal of identifying one or more efficacious agents to advance toward a clinical trial. Remote ischemic post-conditioning (RIC) was selected as a candidate therapy for testing.

Methods:
In Stage I, young, healthy mixed-sex mice were randomized into treatment groups by the coordinating center. In Stage II, aged mice, mice with high-fat diet-induced obesity, and spontaneously hypertensive rats were utilized. Each stage included 25% of the study population and efficacy/futility was determined after each stage. RIC was bilaterally administered as the first session occurred immediately after reperfusion, and the second session occurred as close as possible to 12 ± 2 hours at post-MCAo, using an automated blood pressure cuff that delivered 200-mmHg to the hindlimbs for 4 cycles x 5 minutes/cycle and then once per day x 5 days under anesthesia. Sham-conditioned animals were treated with a cuff that did not inflate. The primary outcome measure was a modified corner test on days 7 and 30 post-stroke. MRI was performed at 48 hours and 30 days. Probabilistic index models, which adjusted for covariates of interest, were fit to estimate the probability of a lower corner test index (better outcome) between sham and RIC.

Results:
A total of 266 mice (132 sham, 134 RIC) were enrolled in the study, with 50 sham and 51 RIC-treated mice dying within 5 days of stroke. Analysis of all data revealed no significant differences in day 30 alternative corner test index between sham and RIC-treated mice after stroke in young, healthy mice (p=0.449), aged mice (p=0.079), mice with diet-induced obesity (p=0.135), or in spontaneously hypertensive rats (p=0.807). The secondary analysis found that RIC improved day 30 tissue infarction volume by MRI in young, healthy mice (p=0.024 vs. sham) but not in other co-morbid conditions.

Conclusions:
After advancing through Stages I and II, RIC was deemed futile at the end of Stage II, as determined by the modified corner test on day 30. The requirement for repeated daily general anesthesia during RIC administration may have been a complicated factor.
Abstract TMP117: Hyper-Acute Platelet-VWF Interactions Drive No-Reflow In Stroke
Authors: Laroche Audree , Allaeys Isabelle , Campbell Robert , Boilard Eric , Denorme Frederik
Published: January 2025

Introduction:
Despite timely recanalization, some ischemic stroke patients treated with endovascular thrombectomy experience persistent neurological deterioration. This has been partly attributed to no-reflow. Experimental stroke models have indicated a critical role for platelets in this process. However, the mechanism and timing of platelet involvement remain unknown.

Methods:
Transient middle cerebral artery occlusion was performed in C57Bl/6J mice. Intra-arterial blood was sampled directly from the brain immediately after reperfusion. In a different cohort, intra-venous blood was sampled immediately after reperfusion. A LEGENDplex assay was used to measure 23 inflammatory cytokines. Endothelial cell activation (von Willebrand factor, VWF) was measured through ELISA. We generated mice with endogenously fluorescent platelets and imaged the penumbra with 2-photon intravital microscopy at different times after stroke onset.

Results:
Immediately after reperfusion, intra-arterial blood sampled from the brain exhibited a distinct inflammatory cytokine profile compared to intravenous systemic blood samples. IL-1alpha, IL-1beta, and IL-6 were significantly elevated in the intra-arterial blood samples compared to the intravenous blood samples. These cytokines have been reported to influence the release and activity of VWF, a hemostatic protein secreted by activated endothelial cells. VWF levels increased both locally (3-fold) and systemically (2-fold) at the onset of reperfusion compared to baseline. The thrombogenicity of VWF is limited by ADAMTS13. Interestingly, ADAMTS13 activity was strongly reduced (2-fold) locally in the reperfused brain, while it remained normal systemically. These results suggest a prothrombotic imbalance of VWF localized in the reperfused ischemic stroke brain. VWF traps platelets, and excessive VWF activation leads to thrombosis. Therefore, we imaged the reperfused brain in mice using 2-photon intravital microscopy. Immediately after the onset of reperfusion, we observed VWF capturing platelets, resulting in the formation of platelet-rich thrombi that disrupted blood flow in the penumbra. Inhibition of platelet binding to VWF using a monoclonal antibody prevented this and resulted in greatly improved stroke outcomes.

Conclusions:
We found that ischemic stroke causes a local cytokine storm which potentiates VWF-mediated platelet accumulation in the reperfused brain contributing to no-reflow and exacerbated stroke outcomes.
Abstract TMP120: CYB5R3 T117S Enlarges Cerebral Infarct Volume and Platelet Activation in Mice Subjected to Transient MCAO-induced Ischemic Stroke
Authors: Wood Katherine , Chowdhury Fabliha , Taiclet Stefanie , Ibanez Laura , Lee Jin-moo , Straub Adam
Published: January 2025

Background:
Americans of African ancestry (AA) show disparities in ischemic stroke when compared to Euro-Americans: two-fold more stroke prevalence and mortality, greater stroke disability and post-stroke complications, and slower recovery. Thromboembolic ischemic stroke involves platelet hyperactivity, which stroke-related oxidative stress promotes. The nitric oxide (NO)-soluble guanylate cyclase (sGC)-guanosine 3',5'-cyclic monophosphate (cGMP) pathway regulates vascular and platelet homeostasis. Oxidized (Fe
3+
) sGC heme is NO-insensitive, lessening cGMP generation for vascular relaxation and platelet quiescence. Cytochrome b5 reductase 3 (CYB5R3) is a methemoglobin reductase with multiple functions, including NADH-supported redox cycling (Fe
3+
-> Fe
2+
) of sGC heme. More than 40 variants of CYB5R3 exist. The T117S variant (threonine to serine substitution) has high frequency expression (23%) almost exclusively in AA persons (<1% other races) and has hypomorphic activity (~50%). Clinical data reveal more ischemic stroke (baseline NIHSS
P
=0.018) and delayed recovery (90 days MRS
P
=0.10) in carriers of T117S versus WT CYB5R3. We thus hypothesized that T117S increases risk for ischemic stroke and poor outcomes via hyperreactive platelets.

Methods:
Crispr-generated T117S mice (C57Bl6 background) and wild type (WT) mice (male, aged 3 mo) underwent transient MCAO (50 min occlusion, 24 hr reperfusion) +/- 3-week pretreatment with Bay54-6544, an NO-independent drug that activates sGC with oxidized (Fe
3+
) or apo-heme. At sacrifice, blood was collected (5% EDTA) and brains stained with triphenyltetrazolium chloride to assess infarct volume. Platelets isolated by gentle serial centrifugation (110 g for plasma separation, 600 g for platelet separation) were probed by Western blot for platelet activation.

Results:
Untreated T117S mice displayed larger infarct volume (
P
=0.0171) and platelet activation than WT mice (vWF
P=
0.005, CD36
P=
0.051, EPO
P=
0.055, STIM1
P
=0.038). Bay54-6544 equalized T117S and WT infarct volumes (
P
=0.684) and decreased post-stroke T117S platelet activation (vWF
P=
0.0002, CD36
P=
0.038, EPO
P=
0.001, STIM1
P
<0.0001). We conclude that ischemic stroke activates platelets more in T117S mice versus WT, which Bay54-6544 pretreatment disrupts. For AA persons, T117S may predict increased risk for ischemic stroke. Prophylactic use of Bay54-6544 may lessen platelet contributions to ischemic stroke in T117S carriers and improve recovery times.
Abstract TMP50: How Often Do Patients Sleep Through the Onset of Ischemic Stroke?
Authors: ANDREASYAN LYNETTE , Saver Jeffrey
Published: January 2025

Introduction:
The advent of wireless monitoring technologies to detect stroke onset during sleep has the potential to accelerate reperfusion treatment in the 20-25% of patients with wake-up stroke. Monitoring technologies will hasten stroke detection in patients who sleep through stroke onset but not in patients who are awakened by stroke onset. The relative frequencies patients who stay asleep after onset compared with patients who wake up with onset has not been well

delineated.

Methods:
We performed a systematic search and meta-analysis of studies comparing diffusion-weighted imaging–fluid-attenuated inversion recovery (DWI-FLAIR) mismatch frequencies in wake-up stroke (WUS) compared with clear onset time stroke (COS). Differences in WUS vs COS decay curves in frequency of FLAIR-DWI mismatch with longer time from symptom detection to imaging were used to estimate the time of stroke onset during sleep.

Results:
Two studies of WUS and COS patients met selection criteria, collectively enrolling 443 patients (201 WUS, 242 COS). The frequencies of FLAIR-DWI mismatch at different intervals from symptom-detection-to-imaging are shown in Figure 1. For COS patients, frequency of mismatch presence declined gradually: <2h 60%; 2-3h 53%; 3-4h 41%; 4-5h 37%; 5-6h 11%. In contrast, for WUS patients, <2h patients had similar mismatch rates to <2h COS patients but

mismatch frequency then declined precipitously in all later time windows: <2h 50%; 2-3h13%; 3-4h 13%; 4-5h 6%; 5-6h 12%. Among the WUS patients: 16.9% had detection-to-imaging time in the <2h time period in which mismatch was nearly equally present as in COS patients; 70.1% had detection-to-imaging times with mismatch rates whose COS equivalents indicated stroke onset 1-8h prior to awakening; and 13.0% had detection-to-imaging times of indeterminate

stroke onset time.

Conclusions:
About 5 of every 6 patients with stroke first detected on awakening had remained asleep for 1-8 hours after stroke onset, while 1 of every 6 awoke at the time of, or soon after, onset. These findings indicate that wireless monitoring technologies to detect stroke start during sleep would accelerate stroke detection in many WUS patients.
Abstract TMP51: Association between genetic variation and acute stroke characteristics
Authors: Schwarz Anne , Chakraborty Stuti , Tavenner Bethany , Feldman Marc , Rosand Jonathan , Parodi Livia , Liew Sook-lei , Holman E. Alison , Cramer Steven
Published: January 2025

Introduction:
Strokes lead to acute deficits with wide-ranging severity. Genetic variation may explain some of these inter-subject differences. The current report examined the relationship that candidate genetic variants have with acute injury and acute behavioral deficits. We hypothesized that variants known to be associated with poorer stroke recovery would also be associated with more a severe acute presentation.

Methods:
Infarcts were outlined on clinical scans acquired during acute stroke admission as part of the STRONG (“Stroke, sTress, RehabilitatiON, and Genetics”) study and resampled to MNI152 brain standard space. Multivariable linear regression modeling was used to examine association with genetic measures known to be related to stroke outcome: 3 single nucleotide polymorphisms (SNPs): BDNF (rs6265), ACE (rs4291), and FAAH (rs324420), plus ApoE e4 and ApoE e2; a dopamine polygene score was also explored. Acute injury (infarct volume) and acute deficits (NIHSS score, grip strength, and acute stress disorder inventory (ASDI)) were each examined as the dependent measure in separate models that used age, gender, and ancestry as covariates. To understand where in the brain these relationships occurred, voxel lesion symptom mapping (VLSM) was used to test for associations between acute injury and each genetic measure.

Results:
In 448 subjects (age 63.4±14.4 yr (mean±SD), 43.1% females), lesion volume ranged from 0.46 to 535.13 cc and involved cortical grey matter in 63% of patients. Larger lesion volume was associated with presence of the ACE SNP (β=8.77, p=0.03); lower NIHSS score, with ApoE e4 (β=-1.69, p=0.04); greater grip strength, with ApoE e2 SNPs (β=6.78, p=0.03); and higher ASDI, with the ACE SNP (β=0.56, p=0.05). VLSM revealed that acute injury to the postcentral gyrus was significantly more likely in the presence of the ACE SNP (z=-3.5), and that acute injury to the calcarine fissure was significantly more likely in the presence of the BDNF SNP (z=-2.53).

Conclusions:
Genetic variants known to be associated with differences in stroke recovery are also related to acute stroke deficits and injury. In particular, a common variant in the gene for ACE was associated with differences in lesion volume and location, findings that may suggest a personalized medicine approach to acute therapy. Measures of genetic variability may be useful to understand inter-subject differences in acute injury and symptom severity, and may have therapeutic implications.
Abstract TMP54: Development and testing of a fully automated tool for the detection, segmentation, and characterization of cervical carotid atherosclerotic disease
Authors: Zhang Jianhai , Barakhanov Kazbek , Kaveeta Chitapa , Alhabli Ibrahim , Pensato Umberto , Ramkumar Raksha , MacDonald Ethan , Singh Nishita , Menon Bijoy , Qiu Wu , Ganesh Aravind
Published: January 2025

Background:
Rapid, accurate diagnosis and characterization of carotid atherosclerosis can help prevent disabling strokes. Although carotid plaques can be identified on CT angiography (CTA), interpretation is challenging for frontline physicians. Quantification of plaque volume/composition requires much manual effort. We developed and tested a fully automated tool for segmenting carotid lumens and delineating atherosclerotic plaque, distinguishing between calcific and hypodense components.

Methods:
We used 528 consecutive cases with CTA head/neck from a population of 7,745 patients with ischemic stroke and transient ischemic attack in an entire province (Alberta) presenting from 1-April-2016 to 31-March-2017. Trained readers supervised by a radiologist manually segmented right and left carotid artery lumens from 3 vertebral bodies below the bulb to 3 above, and segmented regions of carotid atherosclerotic plaque, regardless of degree of stenosis, separately labelling calcific and hypodense components. Cases were split 80/20 between training and testing datasets. The fully automated pipeline included coarse-scale detection of regions of interest, a two-stream U-shaped network for detection and segmentation of lumens and plaques, and a geometry-based inference algorithm to distinguish left and right labels. We evaluated plaque detection using diagnostic performance measures and segmentation using the Dice coefficient.

Results:
422 cases were used for training and 106 for testing. In testing data, the fully automated tool achieved excellent performance for bilateral segmentation of carotid lumens (Dice 0.91, 95%CI:0.90-0.92, e.g.
Figure 1
). For detection of calcific and hypodense plaque components, respectively, the model achieved sensitivity of 96.5% (95%CI:89.3-99.1%) and 97.3% (89.6-99.5%), specificity of 95.2% (74.1-99.8%) and 75.8% (57.4-88.3%), positive predictive value of 98.8% (92.6-99.9%) and 89.9% (80.5-95.2%), negative predictive value of 87.0% (65.3-96.6%) and 92.6% (74.2-98.7%), and accuracy of 96.2% (90.1-98.8%) and 90.6% (82.9-95.1%, e.g.
Figure 2
). Dice score was 0.73 (0.69-0.76) for calcific plaque and 0.53 (0.49-0.57) for hypodense plaque.

Conclusions:
Our fully automated tool achieved good performance for detection and segmentation of carotid plaques. Calcific and hypodense plaque volumes can be automatically generated from these labels. Efforts are underway to further optimize the specificity and segmentation performance for hypodense plaques.
Abstract TMP57: Cerebral Blood Reserve Predicts Early Neurological Deterioration in Minor Stroke with Large Vessel Occlusion or Severe Stenosis
Authors: HE ZHIJIAO , Hong Lan , Li Siyuan , Wang Xinru , Zhang Anqi , Cao Nan , Cheng Xin , Qiang Dong
Published: January 2025

Introduction:
Literature demonstrates that nearly one-third of acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) or severe stenosis arrive at the emergency room with mild symptoms, attributed to favourable collateral status. However, approximately 20~40% of patients with mild symptoms due to LVO or severe stenosis are at risk of early neurological deterioration (END) as a consequence of subsequent collateral failure post arrival. This study aimed to identify the difference of collateral patterns between mild stroke patients with END and those without.

Methods:
AIS patients presenting within 24 hours from last known well, with a baseline NIHSS≤5 and anterior circulation LVO or severe stenosis were included. Patients who underwent endovascular treatment before END were excluded. END was defined as an increase in total NIHSS≥4 or NIHSS≥2 for any item within 72 hours, without evidence of parenchymal hemorrhage. Collateral flow was rated as the Tan scale (leptomeningeal collaterals) and cerebral blood volume (CBV) index (cerebral blood flow reserve). A good leptomeningeal collateral score (goodCS) was defined as Tan scale≥2 (poorCS: Tan scale <2). CBVindex was calculated as the ratio of mean CBV within Tmax>6s lesion over the mean CBV of Tmax<4s area.

Results:
A total of 237 AIS patients with mild symptoms due to anterior circulation LVO or severe stenosis were included and END occurred in 22% of the patients. Stepwise logistic regression analysis revealed that higher CBVindex and poorCS were associated with the increased risk of END occurrence. The optimal threshold of CBVindex predicting END was 0.735 (sensitivity: 0.83; specificity:0.48). Accordingly, patients were divided into four groups: group1: CBVindex<0.735+ poorCS; group2: CBVindex<0.735+goodCS; group3: CBVindex>0.735+goodCS; group4: CBVindex>0.735+ poorCS. Further analysis showed that that patients with CBVindex>0.735 and poorCS (group 4) were most likely to present with END (logistic OR[95%CI]: 5.18[1.22,22.18] P=0.026).

Conclusions:
Higher CBVindex and poor leptomeningeal collaterals were independent predictors of END in patients with mild symptoms due to anterior circulation LVO or severe stenosis. Therefore, we hypothesize that though higher CBVindex reflects favorable collaterals at baseline, higher CBVindex combined with the absence of goodCS indicates insufficient blood flow reserve, leading to collapse of collateral flow during acute phase, therefore, the occurrence of END.
Abstract TMP77: Robotic-Guided Implantation of 3D-Printed Hydrogel Scaffolds to Enhance Axonal Regeneration and Functional Recovery After Stroke: A Novel Minimally Invasive Surgical Approach
Authors: Nouduri Sirisha , Liang Lucy , Chalivoy Lucas , Quispe Johan , Ibrahim Souha , Oulmas Ali , Andre Arthur , François Quentin , Duplat Bertrand , Koffler Kobi , Pirondini Elvira , Gonzalez-Martinez Jorge
Published: January 2025

Ischemic strokes often disrupt white matter (WM) microstructure, particularly affecting the corticospinal tract (CST) in the internal capsule (IC), leading to significant motor deficits. While evidence shows that axon sprouting occurs post-stroke, it often follows erratic paths, limiting functional recovery. Recent advances in 3D-printed hydrogel scaffolds have shown promise in guiding axon regeneration in spinal cord injury models. We hypothesize that implanting these scaffolds at white matter sites affected by stroke, aligned with CST fibers, will enhance functional axonal regeneration and motor recovery. Our aim is to develop and validate a precise and clinically applicable scaffold delivery system for future human studies.

We have developed a novel, minimally invasive stereotaxic method for the precise deployment of 1.3 mm diameter scaffolds within the IC of non-human primates (NHPs). Our approach utilizes a clinically available stereotactic robot (ROSA, ZimmerBiomet) combined with a linear cannula system (AlphaOmega) to plan scaffold placement. Then, we attempted to deploy scaffolds devices into thermally coagulated lesions in NHPs (n=2) and simulated lesions within hydrogel phantoms (n=2). Post-implant MRI, co-registered with high-resolution diffusion tensor imaging were applied to check for scaffold placement accuracy (n=4). We further complement the scaffold placement method by using a novel neurosurgical microrobot (Robeauté) designed for navigation along 3D nonlinear curves, with accuracy confirmed by CBCT imaging in phantom tests.

Our implantation methods accurately placed scaffolds in the intended locations and orientations, aligning with CST fibers in both phantom models and NHP brains. The deviation angle between the scaffold and CST fibers was 17.83° (SD 6.71°, n=3). The scaffolds were precisely positioned within the IC, validating our approach. Our robot-guided method accurately steered them to their intended position, demonstrating minimal errors in targeted white matter regions.

The methods described are poised for clinical translation, potentially extending the applicability of scaffold technology for improving motor function post-stroke. We are preparing NHPs for behavioral and upper limb motor assessments to evaluate the impact of scaffold implantation on axon regeneration, recovery, and performance. This research aims to enhance our understanding of ischemic stroke and develop innovative therapies to restore motor function in patients.
Abstract TMP78: Beyond Recanalization: Predicting Poor Outcomes in Successful Vertebrobasilar Thrombectomy
Authors: Doheim Mohamed , Rios Rocha Lucas , Katano Takehiro , Al-Qudah Abdullah , Khalifa Moustafa , Almast Anmol , Miao Christopher , Pillai Bharat , Palegar Thanmayi , Rocha Marcelo , Starr Matthew , Bhatt Nirav , Lang Michael , Gross Bradley , Raul Nogueira , Al-Bayati Alhamza
Published: January 2025

Background:
Successful recanalization following endovascular thrombectomy (EVT) in vertebrobasilar artery occlusions (VBAOs) does not uniformly translate into favorable functional outcomes. Identifying predictors of futile recanalization is critical for improving patient selection and treatment strategies. This study aimed to compare patients with good versus poor functional outcomes despite successful recanalization in VBAO and to establish predictive factors for futile recanalization.

Methods:
We retrospectively analyzed patients who achieved successful recanalization after EVT for VBAO from a prospectively maintained database between 2014-2024. Functional outcomes were assessed using the modified Rankin Scale (mRS) at 90 days; dichotomized into good (mRS 0-3) and poor (mRS 4-6) outcomes. Demographic data, clinical characteristics, procedural variables, and imaging findings were compared between the groups using pairwise comparisons and multivariable logistic regression models to identify predictors of futile recanalization.

Results:
Among the 163 patients who qualified for final analysis, 73 (44.8%) had good functional outcomes, while 90 (55.2%) had poor outcomes despite successful recanalization. Age (72 years vs. 64 years, p=0.0014), baseline NIHSS score (22 vs. 14, p<0.0001), and serum glucose levels (142 mg/dL vs. 124 mg/dL, p=0.0109) were significantly higher in patients with poor outcomes. In addition, intubation (57.1% vs. 25.4%, p<0.001) and prior history of diabetes mellitus (34.4% vs. 17.8%, p=0.017) and coronary artery disease (33.3% vs. 16.4%, p=0.014) were more prevalent in the poor outcome group. Multivariable analysis confirmed that advanced age (OR 0.73, 95% CI: 0.57-0.93, p=0.012), higher serum glucose (OR 0.90, 95% CI: 0.82-0.99, p=0.025), NIHSS at 24-36 hours post-last known well (OR 0.61, 95% CI: 0.38-0.98, p=0.039), and mRS at discharge (OR 0.0001, 95% CI: 0.0002-0.064, p=0.005) were independent predictors of poor functional outcomes, indicating futile recanalization. A subgroup analysis of patients with complete recanalization (mTICI 2c/3) further validated these findings.

Conclusion:
Futile recanalization after EVT for VBAO is linked to older age, elevated serum glucose levels, higher NIHSS scores at 24-36 hours, and poor mRS at discharge. These factors should be carefully considered in clinical decision-making to improve patient selection for EVT in VBAO.
Abstract TMP80: Outcomes in a national cohort of patients with ischemic stroke who underwent mechanical thrombectomy and decompressive craniectomy were unchanged following extension of the thrombectomy window
Authors: Gallagher Aaron , Levitt Michael , Tirschwell David
Published: January 2025

Introduction:
In 2015, mechanical thrombectomy (MT) was established as an essential treatment for large-vessel occlusion ischemic stroke (LVO). Since then, trials have expanded the population eligible for MT by demonstrating its benefit in patients with LVO who present later to care and with more extensive infarct. As the eligibility criteria for MT ease, more patients will undergo the procedure who have risk factors for complications – such as malignant edema or hemorrhagic conversion – that require decompressive craniectomy (DC). Though MT and DC in ischemic stroke have been studied independently, the outcomes of patients who undergo both procedures is unknown. We present a case series using a national database of patients who underwent MT and required DC to understand their profile and health outcomes.

Methods:
Using the National Inpatient Sample (NIS), an all-payer national healthcare utilization database, patients admitted between the years 2016 and 2021 for ischemic stroke who underwent MT and required DC were identified via ICD-10 codes. Logistic regression was performed to identify patient factors independently associated with DC after MT.

Results:
Of the 31,234 patients admitted for LVO who received MT between 2016-2021, 764 (2%) underwent DC (Table 1). Younger age (p < 0.001), non-white race (p < 0.001), a higher NIHSS (p < 0.001), and lower rates of atrial fibrillation were independently associated with DC after MT. Although the number of patients undergoing MT plus DC increased annually, this rise was proportional to the overall number of MT patients. Admissions with MT and DC were nearly 2.5 times longer than those with MT alone (20 days versus 8.4 days, p < .001, Table 2) and associated with increased rates of mortality (25% versus 12%, p < 0.001) and a higher level of care after discharge (p < 0.001).

Conclusion:
Rates of DC after MT did not change following extension of the thrombectomy window to 24 hours. DC after MT resulted in a heavy burden of morbidity and mortality, similar to levels previously published for DC after ischemic stroke without MT. In conclusion, our findings suggest that expansion of MT eligibility criteria has not increased the risk for DC and that practice guidelines developed from trials in stroke patients who underwent DC but not MT may also be applicable to patients with DC after MT. Recent large core trials have further expanded the MT population, necessitating continued examination of the relationship between MT and DC.