bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP178: Evaluation of Low NIHSS Subitems Association With LVO Detection in Large Telestroke Database
Authors: Sevilis Theresa , Fowler Mariecken , Avila Amanda , Heath Gregory W , Gao Lan , Collins Oleg , Boyd Caitlyn , Devlin Thomas
Published: February 2024

Background:
The benefits of mechanical thrombectomy in low NIHSS score (<6) is unclear and undergoing investigation. Current acute stroke guidelines do not address the utilization of computed tomography angiography (CTA) in low NIHSS largely due to a paucity of data leading to great variation in clinical practice. Understanding the predictive value of NIHSS subitems for LVO may help guide imaging selection.

Methods:
Acute stroke consultations seen in the emergency department in 227 facilities (27 states) from July 1, 2021 to December 31, 2021 were extracted from the TeleCare by TeleSpecialists
TM
database. The encounters with CTA performed were reviewed for LVO detected, and NIHSS score with individual subitems. Logistic regression analysis was performed on the NIHSS subitems in total and at NIHSS cutoff points of ≤6, ≤4, and ≤2.

Results:
A total of 12,668 patients had complete NIHSS subitems available with 1,459 (11.5%) having an LVO and 11,209 without an LVO were extracted. There is a significant difference in the ORs for each subitem. The ORs for patients with NIHSS ≤6 subitems: Level of Consciousness 1.11 (p=0.626), Consciousness Questions 1.36 (p<0.001), Consciousness Commands 1.94 (p<0.001), Best Gaze 1.61 (p=0.061), Visual Field 1.65 (p<0.001), Facial palsy 1.71 (p <0.001), Motor Arm-left 1.43 (p <0.001), Motor arm-right 1.03 (p=0.840), Motor leg-left 0.97 (p=0.758), Motor leg-right 0.83 (p=0.103), Limb ataxia 1.09 (p=0.545), Sensory 0.67 (p=0.001), Language 1.92 (p<0.001), Dysarthria 1.81 (p<0.001), and Neglect 5.78 (p<0.001). Trends in subitems with each lower cutoff were increased odds of LVO with Consciousness Commands, Visual Fields, Language, and Neglect, and lower odds of LVO with Sensation.

Conclusions:
This analysis shows the limitations of the NIHSS subitems to predict LVO. Despite the trend of lower odds of LVO for Sensation, even with the NIHSS cutoff of ≤2 there would have been 7 LVOs missed. There are 6 subitems showing statistical significance at an NIHSS cutoff of ≤2 which suggests that an NIHSS cutoff, even with these identified subpoints, is not a good CTA candidate selection tool for the detection of all LVOs.
Abstract WP18: Hepatic Copper Dysregulation Induced Neuronal Cuproptosis in Ischemic Stroke: Insights Into Mechanisms and Therapeutic Efficacy of Remote Liver Hypothermia
Authors: Wang Qingzhu , Geng Xiaokun , Li Fengwu , Ding Yuchuan
Published: February 2024

Objective:
Serum copper level was increased in ischemic stroke, which was associated with disorder in hepatic copper metabolism. This study aims to determine the link between the elevation in serum copper levels following ischemic stroke, the consequent disorder in hepatic copper metabolism, and copper-induced neuronal death (cuproptosis). We sought to elucidate the role of remote administration of hypothermia (RAH) in liver, attenuating these detrimental processes and mitigating associated brain injuries.

Methods:
We subjected 80 adult Sprague-Dawley rats to 2-h middle cerebral artery occlusion (MCAO) followed by 6, 24 or 48 h reperfusion. Brain damage was evaluated by infarct volume, neurological deficit, and apoptotic cell death. Cuproptosis was measured by cerebral copper content and expressions of copper uptake protein (SLC31A1) and mitochondrial function proteins (SDHB, LIAS, FDX1, DPYD). Liver injury was determined by AST, ALT, and LDH in serum. Hepatic and serum copper metabolism, and regulatory molecules (HIF-1α, ceruloplasmin) were measured. In order to suppress liver copper metabolism and thus brain cuproptosis, RAH in liver was conducted 30 minutes pre-reperfusion.

Results:
Significant infarction, neurological deficit, and heightened apoptotic cell death were observed after stroke. Cerebral copper content and SLC31A1 expression were increased, while expressions of SDHB, LIAS, FDX1, and DPYD were diminished post-ischemic stroke, indicating a mitochondrial-related neuronal cuproptosis. 24 h post-reperfusion, there was a surge in serum liver injury markers. HIF-1α and ceruloplasmin were increased in liver post-stroke, with a concomitant decrease in hepatic copper and increase in serum copper levels. RAH mitigated hepatic copper imbalance and lowered serum copper via the HIF-1α/ceruloplasmin pathway, thus significantly attenuated neuronal cuproptosis, minimizing brain injury.

Conclusions:
The increase of cerebral copper content in ischemic stroke was derived by liver, which, in turn, intensified mitochondrial-related neuronal cuproptosis, exacerbating brain injury. RAH effectively counteracted the hepatic copper imbalances and hampered neuronal cuproptosis, producing neuroprotective benefits.
Abstract WP180: Novel Machine Learning Model for Prediction of Futile Recanalization in Acute Ischemic Stroke Patients With Anterior Circulation Large Vessel Occlusion
Authors: Cunningham Conor , Zohdy Youssef , Elawady Sameh Samir , Matsukawa Hidetoshi , Sowlat Mohammad-Mahdi , Uchida Kazutaka , Zandpazandi Sara , Orscelik Atakan , Maier Ilko , Al Kasab Sami , Jabbour Pascal M , Kim Joon-Tae , Quintero Stacey C , rai ansaar , Starke Robert , Psychogios Marios , Samaniego Edgar A , Arthur Adam S , Yoshimura Shinichi , Cuellar Hugo , Howard Brian , Alawieh Ali M , Romano Daniele G. , Tanweer Omar , Mascitelli Justin , Fragata Isabel , Polifka Adam , Osbun Joshua , Crosa Roberto , Matouk Charles C , Park Min S , Levitt Michael , Brinjikji Waleed , Moss Mark , Dumont Travis , Williamson Richard , Navia Pedro , Kan Peter , De Leacy Reade A , Chowdhry Shakeel A , Ezzeldin Mohamad , Spiotta Alejandro M
Published: February 2024

Introduction:
Up to 50% of acute ischemic stroke (AIS) patients who undergo successful mechanical thrombectomy (MT) fail to achieve favorable outcomes (futile recanalization). In this study we aim to develop a machine learning (ML) model to predict futile recanalization (FR) in AIS patients who undergo MT.

Methods:
We used data from an ongoing large, multicenter database from 2013 to 2023. We included AIS patients treated with MT for ICA, M1, or M2 occlusion with successful recanalization (modified Thrombolysis in Cerebral Infarction [mTICI] score ≥ 2C) and procedure durations under 60 minutes. FR was defined as successful recanalization with 90-day modified Rankin Scale (mRS) 3-6. The dataset was divided into 75% for training and 25% for external validation. Using the Caret Package in R, multiple models were tested, and their performances were evaluated by the area under the curve (AUC) of receiver operating. Both baseline and pre-interventional characteristics were incorporated into the model. The selected model was then externally validated on a 25% validation dataset.

Results:
Among 2,546 qualified patients, FR occurred in 1,342 (52.7%). In univariate analysis, baseline characteristics were significantly different between FR and non-FR groups. The M5P model demonstrated the highest performance (AUC: 0.833; 95% CI: 0.7989-0.852; PPV: 0.8101) in comparison to other tested models such as logistic regression (AUC: 0.74), RF (AUC: 0.78), J48 (AUC: 0.78), SVM (AUC: 0.79), and GB (AUC: 0.79). The external validation of the model showed satisfactory results (AUC: 75.25; 95% CI: 70-80; PPV: 76.87).

Conclusion:
Utilizing clinical, pre-procedural, and imaging parameters, the M5P model can efficiently predict F) in AIS patients before attempting MT. This tool can assist neurointerventionalists in adequately choosing their MT candidates.
Abstract WP185: Intraarterial Eptifibatide as an Adjunct to Refractory Multi-Pass Mechanical Thrombectomy
Authors: Amireh Abdallah , Sahito Sindhu , Singh Zamir , Wan Erica , Abualnadi Ibrahim , Snyder Thomas , Scarpiello Sean , Ghori Arifa , Percival Brigitte , Panezai Spozhmy , Zacharatos Haralabos
Published: February 2024

Eptifibatide is a glycoprotein IIb/IIIa inhibitor. Its intraarterial (IA) administration as adjunct therapy during mechanical thrombectomy (MT) lacks substantial supportive evidence.

Objective:
To identify any correlation between IA eptifibatide (135 mcg/kg) during MT and recanalization, clinical and safety outcomes.

Methods:
Retrospective data collection was performed at a single center. MT cases for strokes between 2020 and 2022 were reviewed. To be included, two or more passes of MT using stent retrievers in combination with aspiration must have occurred. Favorable functional outcomes were identified as mRS of 0 to 2 and NIHSS of 0 to 4 at discharge. A recanalization score of mTICI 2b to 3 was considered as successful recanalization. Any ICH within 24 hours post procedure was reported.

Results:
Out of 96 total patients, IA eptifibatide was used in 49 patients (51%). Tables 1 and 2 list Patients’ characteristics and outcomes in both groups, respectively. There were significantly higher chances of 2 or less passes occurring after IA eptifibatide before procedure termination (OR 5.30; 95% CI: 1.89-14.89, P 0.002). However, IA eptifibatide did not influence chances of achieving successful recanalization (OR 0.592; 95% CI:0.228-1.539, P 0.28), having a favorable functional outcome at discharge (mRS ≤ 2 OR 0.58; 95% CI: 0.52-1.38, P 0.22. NIHSS 0-4 OR 0.57; 95% CI: 0.24-1.38, P 0.22), or the occurrence of any ICH within 24 hours (OR 2.86; 95% CI: 0.71-11.52, P 0.14).

Conclusion:
Our findings do not support the use of IA eptifibatide in MT. Such practice could be adding unnecessary steps to a time sensitive procedure. These findings need validation by prospective randomized trials.
Abstract WP190: Comparison of Collateral Score to ASPECTS to Exclude "Very Large" Infarct Core Volumes in Anterior Circulation Large Vessel Occlusion Strokes at 0-24 Hours
Authors: Lin Sidney , Raince Avtar , Byrns Kory
Published: February 2024

Purpose:
ASPECTS<3 was an explicit exclusion criterion in the SELECT2 trial to exclude "very large" infarcts (>100mL) for reperfusion using endovascular thrombectomy (EVT). While specific, ASPECTS<3 may be too insensitive of a threshold on noncontrast CT at 0-24 hours (especially 0-6 hours). We aim to determine if CTA based Collateral Score (CS) can be a more sensitive surrogate marker for infarct core volume (ICV)>100mL while maintaining similar specificity to ASPECTS.

Methods:
Retrospective analysis included consecutive stroke patients arriving within 24 hours of onset, with intracranial ICA and/or M1 occlusion on CTA, and had concurrent CT perfusion. RAPID AI software estimated ICV using the rCBF<30% threshold. CS was scored on CTA using the method of Tan et al on a 4-point scale for % collaterals compared to contralateral side:

0

none,

1

>0 but <50%,

2

>=50 but <100%, and

3

100%. ROC curve analysis was used to find the optimal CS cutpoint with high specificity for ICV>100mL. Sensitivity and specificity of that CS threshold vs ASPECTS<3 were compared using the N-1 chi square test.

Results:
164 patients were included with median (IQR) age of 74 (66-84), NIHSS of 20 (12-25), and time of onset-to-CT of 4 hours (2-7.5). The LVOs were 17 ICA (10.4%), 108 M1 (65.9%), and 39 both (23.8%), with median ICV of 12mL (0-45). 16 patients had ICV>100mL (9.8%) with median of 136mL (105-172). Using ASPECTS<3 identified only 1 of these (ICV of 118mL at 18.5 hours), sensitivity of 6.3% (95% CI: 0.16-30.2%), with no false positives, specificity of 100% (95% CI: 97.6-100%). ROC analysis for CS showed AUC=0.818 (p<0.001), with maximal specificity at CS=0 (no visible collaterals). Using CS=0 identified 6 of these infarcts, sensitivity of 37.5% [95% CI: 15.2-64.6%], with 2 false positives, specificity of 98.7% [95% CI: 95.2-99.8%]. The 2 false positives were ICV of 97mL at 2 hours and 96mL at 3 hours. The improved sensitivity of CS=0 over ASPECTS<3 was significant (p=0.036) while the difference in specificity was not (p=0.144).

Conclusion:
In our cohort of LVOs, CS=0 was a more sensitive surrogate marker for ICV>100mL compared to ASPECTS<3 while maintaining near 100% specificity. If confirmed in future prospective studies, CS=0 has the potential to further streamline patient selection for EVT.
Abstract WP191: Impact and Determinants of Door In-Door Out Time for Stroke Thrombectomy Transfers: Real World Analysis of a Large Hub-and-Spoke Network
Authors: Ahmed Rashid A , McIntyre Joyce A , Leslie-Mazwi Thabele M , Das Alvin S , Dmytriw Adam A , Hirsch Joshua A , Rabinov James D , Doron Omer , Stapleton Christopher J , Singhal Aneesh B , Rost Natalia S , Patel Aman B , Regenhardt Robert W
Published: February 2024

Introduction:
The mantra ‘time is brain’ cannot be overstated for patients suffering from acute ischemic stroke. This is especially true for those with large vessel occlusions (LVO) requiring transfer to an endovascular thrombectomy (EVT) capable center. We sought to evaluate the spoke hospital door in-door out (DIDO) times for patients transferred to our hub center for EVT.

Methods:
Individuals who first presented with LVO to a spoke hospital and were then transferred to the hub for EVT were retrospectively identified from a prospectively maintained database from January 2019 to November 2022. DIDO was defined as the time between spoke hospital door in arrival and door out exit. Baseline characteristics, treatments, and outcomes were compared, dichotomizing DIDO at 90 min based in the American Heart Association goal for DIDO ≤90 min for 50% of transfers. Multivariable regression analyses were performed for determinants of 90-day ordinal modified Ranking Scale (mRS) and DIDO.

Results:
We identified 194 patients transferred for EVT with available DIDO. The median age was 67 (IQR 57-80), and 46% were female. The median NIHSS was 16 (10-20), 50% were treated with intravenous thrombolysis at a spoke, and TICI 2B-3 reperfusion was achieved in 87% at the hub. The median DIDO was 120 min (97-149), with DIDO ≤90 min achieved in 18%. DIDO was a significant determinant of 90-day ordinal mRS (B=0.007, 95%CI=0.001-0.012, p=0.013), even when accounting for last known well-to-spoke door in, spoke door out-to-hub arrival, hub arrival-to-puncture, puncture-to-first pass, age, NIHSS, intravenous thrombolysis, TICI 2B-3, and symptomatic intracranial hemorrhage. Importantly, determinants of DIDO included Black race or Hispanic ethnicity (B=0.918, 95%CI=0.010-1.826, p=0.048), atrial fibrillation or heart failure (B=0.793, 95%CI=0.257-1.329, p=0.004), and basilar LVO location (B=2.528, 95%CI=1.154-3.901, p<0.001).

Conclusion:
In this real-world analysis of a large hub-and-spoke network, spoke DIDO was the most important period of time for long term outcomes of LVO stroke patients treated with EVT. Determinants of DIDO were identified which require further investigation and motivate system changes that may reduce DIDO and improve patient outcomes.
Abstract WP196: Blood Pressure After Endovascular Therapy: A Systematic Review and Metanalysis of Randomized Control Trials
Authors: Gharaibeh Khaled , Keener Myles , Jumaa Mouhammad A
Published: February 2024

Background and Objectives:
There are limited data evaluating the optimum blood pressure (BP) goal post mechanical thrombectomy (MT) and its effect on outcomes of patients with large vessel occlusions (LVO). The objective of this study was to compare the efficacy and safety of intensive versus less intensive blood pressure control after reperfusion with MT via a systematic review and meta-analysis of randomized controlled trials (RCTs).

Methods:
We searched the PubMed, and Embase to obtain articles related to blood pressure control post MT through September, 2023. The primary outcome was functional independence (modified Rankin Scale [mRS] 0-2) at 3 months. Effect sizes were computed as odd ratio (OR) with random-effect or fixed-effect models.

Results:
Four Randomized Clinical Trials (RCTs) with 1566 patients (762 randomized into intensive blood pressure control vs. 806 randomized into loess intensive blood pressure control) were included. The RCT analysis showed that the likehood of functional independence was less in the more intensive treatment group compared with the less intensive treatment group functional independence (mRS 0-2: OR 0.66, 95% CI 0.54-0.89, P < 0.001). There was no significant increasing the risk of symptomatic intracranial hemorrhage (sICH: OR 1.14, 95% CI: 0.77-1.69, P = 0.51), or mortality ( mortality 1.22, 95% CI: 0.90-1.66, P =0.19).

Conclusion:
This systematic review and meta-analysis indicate that in patients who achieved successful MT for acute ischemic stroke with LVO, intensive BP control was associated with lower likehood of functional independence at 3 months without significant difference in sICH or mortality risk. Results of upcoming RCTs may provide further insight.
Abstract WP198: Balloon Guide Catheter Impact on Angiographic and Clinical Outcomes in Distal Medium Vessel Occlusion Strokes Undergoing Thrombectomy
Authors: Mohammaden Mahmoud H , Dolia Jaydevsinh , Abdelhamid Hend M , matsoukas stavros , Schuldt Braxton R , Johanna Fifi , Kuybu Okkes , Al-Bayati Alhamza , Olive-Gadea Marta , Rodrigo-Gisbert Marc , Requena Manuel , Monteiro Andre , Moreira Ferreira Felipe , Yu Si , Siegler James E , Farooqui Mudassir , Vivanco-Suarez Juan , Ortega-Gutierrez Santiago , Cortez Gustavo , Hanel Ricardo , Hassan Ameer E , Nguyen Thanh , AbdalKader Mohamad , Klein Piers , Salem Mohamed , Burkhardt Jan-Karl , Jankowitz Brian , Colasurdo Marco , Kan Peter , Hafeez Muhammad , Tanweer Omar , Peng Sophia , Alaraj Ali A , Siddiqui Adnan , Nogueira Raul G , Haussen Diogo C
Published: February 2024

Background:
The use of balloon guide catheter (BGC) has been associated with better reperfusion and clinical outcomes in mechanical thrombectomy (MT) for large vessel occlusion strokes (LVOS). The association between BGC and angiographic and clinical outcomes in patients with distal medium vessel occlusion strokes (DMVO) undergoing MT has not been investigated.

Methods:
This is a retrospective analysis of a prospectively collected database from 14 comprehensive stroke centers in the United States and Europe. Patients were included if they had anterior circulation DMVO due to MCA-M3/M4 or ACA-A1/A2-3 and were treated with MT using stentriever, contact aspiration, or a combination of both techniques as first-line therapy. The cohort was divided into two groups: 1) BGC and 2) non-BGC. Uni and multivariable analyses were used to identify predictors of first pass effect (FPE) defined as eTICI grade 2C or 3 after single device pass, as well as mRS0-1, mRS0-2, and mortality at 90 days.

Results:
A total of 199 patients were eligible for analysis. The BGC group (n=73) had comparable baseline characteristics as compared to the non-BGC group (n=126), except for lower median age and frequency of hyperlipidemia, atrial fibrillation, and White patients, and higher frequency of tandems. Procedurally, the BGC group had a less frequent use of contact aspiration (23.3% vs. 53.2%), and higher proportions of stent-retriever use (35.6% vs. 13.5%) and combined technique (41.1% vs. 33.3%; P<0.001) as first-line therapy. A lower number of passes (1 vs. 2, P<0.001), shorter procedure time (40 vs. 46 minutes, P=0.029), and higher FPE rates (53% vs 13%; P<0.001) were observed in the BGC group. On multivariable analysis, the BGC group showed higher rates of FPE (53.4% vs. 13.7%, aOR 6.74, 95%CI [3.08-14.75], P<0.001), 90-day mRS 0-1 (42.9% vs. 27.1%, aOR 2.28, 95%CI [1.06-4.91], P=0.035), and 90-day mRS 0-2 (60.3% vs. 41.5%, aOR 2.47, 95%CI [1.15-5.31], P=0.02). The rates of successful reperfusion at the end of the procedure, sICH, and 90-day mortality were comparable between both groups.

Conclusions:
The present study suggests that the use of BGC in DMVO undergoing MT is associated with improved angiographic and clinical outcomes with no safety concerns. Prospective studies are warranted.
Abstract WP2: Natural History of Large Vessel Occlusion Patients Presenting With Minor Stroke Symptoms
Authors: Chen Alan X , Fiano Emily , Liu Xinyan , Perlman Kerstyn , Fifi Johanna , Majidi Shahram , Kellner Christopher P , Shigematsu Tomoyoshi , Oxley Thomas J , De Leacy Reade A , Shoirah Hazem
Published: February 2024

Background:
Acute ischemic stroke is a leading cause of mortality and disability in the US, with 50% of patients with minor stroke symptoms (MSS). Large vessel occlusion (LVO) is found in 10% of MSS cases and predicts poor neurological outcomes. However, treatment strategies for MSS-LVO lack consensus, and a deeper understanding of the natural history of MSS-LVO is needed.

Methods:
We screened all patients presenting to a large stroke network, from May 2017 to August 2023, for intracranial anterior circulation LVO and MSS (NIHSS %lt 6). Descriptive statistics were applied to demographic, clinical, radiographic, and neurological outcomes data, including early neurological deterioration (END) (NIHSS gain 3+).

Results:
Ninety patients participated in the study, averaging 64.5 years old, with 58.8% male, 48.8% white, 22.2% black, and 16.2% Hispanic. Comorbidities included diabetes (23%), hypertension (67.7%), atrial fibrillation (22%), hyperlipidemia (53%), and smoking (40%). Patients arrived with mean 7 hours (SE 1.6) from LKW, and a mean NIHSS 3.95 (SE 0.40). The majority of patients had baseline mRS of 0-2 (92.6%). Occlusion sites included M1 (38.9%), M2 (40%), and ICA terminus (2.2%). The mean ASPECTS score was 9.4 (SE 0.13). Immediate thrombolytic treatment was delivered to 34% of patients. Out of 90 patients, 31 (34%) suffered END, with mean NIHSS at END of 9.17 (SE 0.85), necessitating rescue endovascular thrombectomy (EVT). Collateral vessel failure caused 87.1% of END cases, clot migration 9.7%, and additional strokes 3.2%. Of the 31 EVT cases, 29 (93%) achieved TICI 2b-3, averaging 3.1 (SE 0.35) passes. ICH occurred in 5 patients; 2 had undergone EVT, although none were symptomatic. At 24 hours and 5 days from presentation, the mean NIHSS were 3.15 and 2.86 respectively, worse in END patients (6.16 vs 1.55, p=0.00, and 6.28 vs 1.14, p=0.00). After 30 days, only 66% of END patients had mRS of 0-2 compared to 84% of non-END patients (p=0.02). Similarly, at 90 days, only 65% of END patients, versus 86% of non-END patients, had mRS of 0-2 (p=0.02).

Conclusion:
The study details the natural history of MSS-LVO, showing a prominent incidence of EVT-requiring END due to collateral failure. Future research should identify high-risk END patients for tailored treatment.
Abstract WP202: Thrombectomy versus Combined Thrombolysis and Thrombectomy for Primary Medium and Distal Intracranial Occlusions: A Propensity-Score Matched Multicenter Analysis
Authors: Dmytriw Adam A , Koneru Manisha , Yedavalli Vivek , Sleem Hazma , Musmar Basel , Regenhardt Robert , Guenego Adrien
Published: February 2024

Background:
Mechanical thrombectomy (MT) has demonstrated superiority over medical therapy for acute ischemic stroke (AIS) with large vessel occlusion (LVO). The role of adjunctive intravenous thrombolysis, such as intravenous tissue plasminogen activator (IVtPA), with MT remains unclear, especially for medium vessel occlusion (MeVO). This multicenter study aimed to compare outcomes between MT alone and MT+IVtPA in patients with MeVO.

Methods:
Data from 827 patients treated at 37 academic centers in North America, Asia, and Europe were collected between September 2017 and July 2021. Propensity score matching was performed to create two well-balanced groups: MT alone and MT+IVtPA. Baseline characteristics, procedural details, and clinical outcomes were analyzed.

Results:
After propensity score matching, 577 patients (315 in the MT alone group and 262 in the MT+IVtPA group) were included in the analysis. The two groups had comparable baseline characteristics, except for longer onset-to-puncture and onset-to-recanalization times in the MT alone group. In univariable regression, all outcomes were comparable between the two groups, except for higher mRS 0-2 rates in the MT+IVtPA group. Multivariable regression analysis showed no significant differences in first pass effect (FPE), number of passes, Thrombolysis in Cerebral Infarction (TICI) scores, rates of mRS 0-1, mRS 0-2, mortality, or intracranial hemorrhage between the groups.

Conclusion:
In patients with primary medium and distal intracranial occlusions, MT alone and MT+IVtPA yielded similar clinical outcomes. These findings suggest that adding IVtPA to MT may not confer additional benefit in this population. Further research is needed to determine the optimal treatment approach for MeVO.
Abstract WP206: Single Center Experience Using the 3-Max Catheter in Medium and Distal Vessel Occlusion
Authors: Ali Aizaz , Rao Rahul , Sharkey Brandon , Gega Alisa , Oliver Marion , Zaidi Fazal
Published: February 2024

Introduction:
Stroke thrombectomy for medium and distal vessel occlusion is a topic of great interest with several clinical trials underway. We describe a single center experience with the Penumbra 3 max aspiration catheter in stroke thrombectomy. In our study, we compare the use of the 3 max as a de novo first pass catheter to its use as a rescue aspiration catheter following attempted thrombectomy with other devices.

Methods:
From January 2017 to January 2023, 84 patients underwent mechanical thrombectomy with use of a Penumbra 3 Max aspiration catheter at our comprehensive stroke center. Of these patients, 26 had 3 Max used as a first pass catheter (de novo) and 58 had it used on subsequent passes (rescue). We retrospectively reviewed these patient charts for demographic variables, and clinical and radiographic outcomes. We compared the effectiveness of the 3 Max catheter in achieving recanalization on first pass when used de novo, to the successful recanalization of a vessel when the 3 Max was used as a rescue device (“rescue rate”).

Results:
There were no significant differences in baseline demographic variables including age, gender, presenting NIHSS, and vascular risk factors between the de novo and rescue groups. There was no significant difference in location of occlusion and IV or IA thrombolytic use between the groups. The rescue rate was higher than the first pass effect [67.2% vs. 38.5%,
X
2
(1,
N
=84) = 6.1, p<.05]. Rates of successful thrombectomy, defined as TICI2c or better, were similar between the de novo and rescue groups (44.4% vs. 40.4%, p=0.722). The de novo group had higher rates of favorable outcome at 90 days (mRS 0-2), but this did not reach statistical significance (44% vs. 28.1%, p=0.158). Hemorrhage and mortality rates between the two groups were low and not statistically significant when compared to each other.

Conclusion:
Medium and distal vessel occlusion carry high rates of morbidity and deserve consideration of endovascular therapy. The Penumbra 3 Max catheter has a higher rescue recanalization rate than first pass recanalization rate. It appears to be a safe and effective device when used in mechanical thrombectomy.
Abstract WP21: Intravenous Alteplase for Unknown Onset Stroke on Prior Antiplatelet Therapy: EOS Individual Participant Data
Authors: Shiomi Yuma , Miwa Kaori , Toyoda Kazunori , Jensen Märit , Inoue Manabu , yoshimura sohei , Naruhiko Kamogawa , fukuda mayumi , Ma Henry , Ringleb Peter , Wu Ona , Schwamm Lee H , Davis Stephen M , Donnan Geoffrey A , Gerloff Christian P , Thomalla Gotz , Koga Masatoshi
Published: February 2024

Introduction:
Although prior antiplatelet therapy (APT) could potentially contribute to bleeding risk, the influence of prior APT on intravenous thrombolysis outcomes remains controversial. We sought to assess the efficacy and safety of intravenous thrombolysis for acute ischemic stroke in patients receiving prior APT

Methods:
Patients with an acute stroke of unknown onset were evaluated using an individual patient-level database of randomized controlled trials comparing t-PA with placebo or standard care from the Evaluation of Unknown Onset Stroke Thrombolysis (EOS) trials. A favorable outcome was defined as a modified Rankin Scale of 0 to 1 at 90-days. Safety outcomes included symptomatic intracranial hemorrhage (sICH) at 22 to 36 hours and 90-day mortality.

Results:
Baseline data on prior APT were available for 780 of 843 patients. Of these, 257 (32.9%) patients were receiving prior APT. Patients with prior APT were older (72 vs. 66 years), and had a higher prevalence of vascular risk factors than those without APT. Overall, there was no interaction between prior APT and treatment effects of alteplase (p interaction=0.23). A favorable outcome was observed in 55 of 125 (45%) patients with prior APT in the alteplase group and in 39 of 132 (30%) patients with prior APT in the control group (adjusted odds ratio [aOR], 2.41 [95% CI, 1.14-5.13]). sICH occurred in 7 patients (5.6%) in the alteplase group but in 1 patient (0.8%) of the controls (aOR, 10.82 [0.63-185.3]). 90-day mortality was observed in 6 patients (6.5%) in the alteplase group compared with 6 patients (6.1%) in the controls (aOR, 1.47 [0.25-8.78]). In patients without prior APT (n=523), favorable outcome was observed in 136 patients (51.3%) in the alteplase group and in 112 patients (45.3%) in the control group (aOR, 1.38 [0.90-2.11]). Additionally, no significant differences were found in terms of safety outcomes between the two groups (sICH: 3 [1.2%] vs. 1 [0.4%]; mortality: 13 [4.9%] vs. 3 [1.1%]).

Conclusion:
Intravenous alteplase exhibited efficacy for acute stroke without increasing the risks of symptomatic intracranial hemorrhage or mortality in patients with prior antiplatelet therapy.
Abstract WP216: Results of a Pediatric Stroke Program Utilizing Stroke Telemedicine Across a Fifteen Hospital Healthcare System in Southern California
Authors: Urbayan Carmen , Rho Howard J , Taleb Shayandokht , Han Paul , Lewis Keith , Gaffney Denise , Ajani Zahra , Ly An , Sangha Navdeep S
Published: February 2024

Background:
The recognition of pediatric stroke symptoms is challenging. A regionwide pediatric stroke program utilizing an educational initiative across 15 emergency departments (ED) coupled with telemedicine was developed to standardize the process for immediate access to stroke experts and decrease door-to-intervention times. This study evaluates the impact of this intervention.

Methods:
Data from the pre- (1/2020-12/2021) vs post-intervention (1/2022-7/2023) including baseline demographics, volumes, and process measure timeframes: Door-to-Telestroke Page, Door-to-CT Interpretation, Door-to-Telestroke Call Back, and Door-to-Needle Time were abstracted. Chi-Square and Wilcoxon Rank Sum were used for statistical analysis.

Results:
There were a total of 92 Telestroke consults, with more in the post group: 35(38%) pre vs 57(62%) post (p=0.04). 52% were female with mean age of 12 (±1.2) years. 78(85%) were stroke mimics: 74% had non-cerebrovascular or migrainous neurological disorders as primary diagnoses. 7(7.6%) patients had interventions: 4(4.3%) thrombolytics, 9(9.7%) arterial or venous thrombectomies. 51% were discharged home and 43% were transferred to an acute care facility for higher level of care. There was no difference between pre- and post-implementation median [IQR] Door-to-Telestroke Page (17.5[14-21] vs 15[11-18] mins); Door-to-CT Interpretation (29[25-32] vs 27[23-29] mins) and Door-to-Needle Time. Median Post Door-to-Telestroke Call Back was faster (pre: 20[17-22] vs post: 16.0[13-18] mins [p=0.03]).

Conclusion:
Systemwide ED education coupled with telemedicine in implementing pediatric stroke systems of care in a large integrated healthcare system improves access to stroke specialists and time-based metrics in this low-volume, high-risk patient population.
Abstract WP218: Risk Factors for Cerebral Aneurysms in Sickle Cell Disease
Authors: González-Barreto Alejandro R , Donahue Manus J , Rodeghier Mark , Davis Samantha , Debaun Michael R , Kassim Adetola A , Pruthi Sumit , Davis L. T , Jordan Lori C
Published: February 2024

Introduction:
Cerebral aneurysm frequency in sickle cell disease (SCD) is higher than in the general population. Specific risk factors explaining this difference have not been previously explored. We hypothesize that increased cerebral blood flow (CBF), low hemoglobin (Hb) levels, and documented risk factors for aneurysms in the general population would be associated with aneurysm development in SCD.

Methods:
Children and young adults with SCD defined as HbSS and HbSβ0 thalassemia were recruited from SCD clinics at an academic medical center and a community health clinic from 2014-2022 along with age and race-matched controls. Written consent and assent were required. Inclusion: ages 6-45 years, study MRI and MRA of the brain, risk factor data collected. MRAs were reviewed and aneurysms were confirmed by consensus of 2 neuroradiologists. CBF was assessed via MRI with pseudo-continuous arterial spin labeling.

Results:
The study population included 183 SCD participants, including 13 (7.1%) with aneurysms. The healthy control group included 77 participants, 3 (3.9%) of these participants had aneurysms, all women. In the SCD sample, 10 of 13 (76.9%) aneurysms occurred in males while 76 of 170 (44.7%) without aneurysms were male (p=0.025). In the aneurysm group, 3 of 13 (23.1%) were smokers versus 8 of 170 (4.7%) without aneurysms (p=0.035). In the SCD aneurysm group, median age was older, 30.9 years versus 17.2 years without aneurysm, (p<0.001). Systolic blood pressure and Hb levels were not different in SCD participants with and without aneurysms, p=0.074 and p=0.358, respectively. However, SBP was 119.7±14.9 with aneurysms vs 113.2±12.3mmHg without aneurysms. Mean gray matter CBF for the SCD group with aneurysms was higher at 86.7± 25.9ml/100g/min compared to 80.8 ± 20.3ml/100g/min in the SCD group without aneurysms, though not significantly (p=0.325).

Discussion:
Increased CBF and low hemoglobin levels were not risk factors for cerebral aneurysms in SCD in this relatively small cohort. Like the general population, age and smoking are risk factors for aneurysm development in SCD. In contrast to the general population, male sex rather than female sex in SCD is an aneurysm risk factor. Based on these data, a larger consortium to study aneurysms in SCD is needed.
Abstract WP220: Structural Connectivity Injury is Associated With Poor Language Outcomes in Perinatal Stroke
Authors: Alhadid Kenda , Chui Carrie , Sullivan Alyssa , Miller Gillian , Tambala Diana , Lynch Anna , Hamel Maura , Musolino Patricia L , Schirmer Markus D
Published: February 2024

Introduction:
Perinatal stroke refers to brain injury sustained between 28 weeks of gestational age (GA) and 28 days of life. Stroke risk in the newborn period is significantly higher relative to other life stages, and over half of all survivors endure lifelong neurological sequalae. Language deficits are observed in many patients, can emerge at any stage in development, and are difficult to predict. Lesion laterality and location are not sufficient to explain language outcomes in a rapidly developing brain with capacities for reassignment of functions to non-injured structures. Structural connectivity studies describe a “rich club” organization of the brain with 6 bilateral highly connected anatomical structures
that form the information backbone for all networks.
This organization has been found to exist as early as 30 weeks GA. The effects of injury to this rich club have been studied in adult stroke patients with respect to stroke severity and outcome. Given that language is a network function, we hypothesized that injury to rich club regions - a measure of structural network disruption - is associated with poor language outcomes in perinatal stroke.

Methods:
Retrospective study that identified perinatal stroke patients in a pediatric stroke clinic database. Clinical and imaging data retrieved included brain MRI scans and longitudinal scores of standardized neuropsychological tests. Multiple linear regression models were created for the following variables: age, sex, Autism Spectrum Disorder diagnosis, lesion volume (cm
3
), and number of rich clubs affected by the stroke. All analyses were conducted using the computing environment R. Significance was set at p < 0.05.

Results:
Cohort of 75 patients was identified. Median time to follow up was 7 years, and median time between the first and last test was 30 months. Lesion volume significantly influenced receptive language outcomes at younger ages (beta = -0.446), however the number of rich clubs affected by the injury was the only significant variable associated with a poor expressive language outcome at follow-up (beta = -0.699).

Discussion:
Number of rich clubs affected by injury, as a global measure of structural network disruption in the neonatal period, can be used to inform language outcome prognostication.
Abstract WP222: Basilar Artery Stenosis in Children With Moyamoya
Authors: Reilly Daniel , Singh Nikita , Rangwala Shivani , Kappel Ari , Orbach Darren , See Alfred Pokmeng , Smith Edward R , Lehman Laura L
Published: February 2024

Introduction:
Moyamoya is a progressive cerebrovascular disease characterized by stenosis of the cerebral arteries in the anterior circulation and less often the posterior circulation. To our knowledge, studies examining the prevalence of basilar artery stenosis do not exist outside of case reports.

Methods:
We retrospectively examined children with moyamoya followed at a single institution from November 2011 through August 2023. Children with moyamoya and basilar stenosis mentioned in their chart were initially included. A pediatric neurologist reviewed all records and neuroimaging to verify diagnosis of basilar artery stenosis.

Results:
Out of our cohort of 331 children with moyamoya, 24 (7.2%) children had basilar artery stenosis. In the group of 24 children with moyamoya and basilar artery stenosis 63% were females. The median age at moyamoya diagnosis was 4.8 years (interquartile range [IQR] 2.2,8.3). At time of diagnosis 16 children (67%) had basilar artery stenosis. The median time from diagnosis was 0 years (IQR 0, 1.3). At time of diagnosis all children had anterior circulation stenosis (internal carotid artery, middle cerebral artery and/or anterior cerebral artery), 13 (54%) had posterior cerebral artery stenosis and 6 (25%) had vertebral artery stenosis. Post-operative strokes following revascularization surgery occurred in 8 (33%) out of the 24 children. An associated disorder was found in 11 (46%) including ACTA2, PHACE syndrome, cranial radiation, trisomy 21, sickle cell disease, neurofibromatosis type 1 and morning glory disc.

Conclusion:
To our knowledge we present the first study to examine prevalence of basilar artery stenosis in a large single center cohort of children with moyamoya. In our cohort 7.2% of children with moyamoya had basilar artery stenosis. A large proportion of children with basilar artery stenosis developed stroke post-operatively. Genetic evaluation may be warranted in children with moyamoya and basilar artery stenosis given that 46% of the children had an associated disorder identified.
Abstract WP223: Cerebral Visual Impairment in ACTA2 Patients Assessed by Virtual Reality Testing
Authors: Tambala Diana , Da Cruz Emily , Lynch Anna , Manley Claire , Bambery Melissa , Kelly Daniel , Alhadid Kenda , Merabet Lotfi , Musolino Patricia
Published: February 2024

Introduction:
Heterozygous missense mutations disrupting arginine 179 (Arg179) in the ACTA2 gene which codes for the smooth muscle-specific isoform of α-actin, cause Multisystemic Smooth Muscle Dysfunction Syndrome (MSMDS). The clinical manifestations of this genetic condition include congenital mydriasis, patent ductus arteriosus, stroke, and/or aortic aneurysms or dissections among many others. White matter injury, impaired autoregulation, and neurovascular coupling (due to the cerebral vasculopathy affecting cerebral perfusion) are known factors that alter neural network performance and processing speed. The lack of a standardized ophthalmologic examination that detects cerebral visual impairment (CVI), precludes an early diagnosis and creates missed opportunities for intervention. There is a paucity of data regarding CVI in MSMDS patients, and through this novel work, we present data defining their visual processing deficits.

Hypothesis:
We hypothesize that: 1) individuals with MSMDS will exhibit more pronounced deficits in visual-spatial processing compared to the control group, and 2) their performance will deteriorate as the complexity of visual tasks increases.

Methods:
Using a virtual reality (VR) based visual search task system, we characterized the impairment of higher-order visual processing in MSMDS patients (n = 4) as compared to healthy controls (n = 13). The VR-based task required searching for targets on a screen among varying levels of visual complexity. Reaction time, gaze error, shifted ellipse area, success rate, and pursuit saccade ratio were statistically analyzed with unpaired group t-tests, with significance being defined as p < 0.05.

Results:
Compared to controls, MSMDS patients took longer to identify the correct target, were less accurate in finding the target, and exhibited greater impairment in performance with an increasing number of distractors. Both groups showed similar task compliance, measured using an off-screen count metric.

Conclusion:
This novel work demonstrates that MSMDS patients exhibit impaired higher-order visual processing. This highlights the need for clinical tools that can assess these difficulties with quantitative methods to guide therapies and improve functional outcomes.
Abstract WP227: Deep Medullary Vein Thrombosis in Neonates
Authors: Laheji Fiza K , Dowling Michael M
Published: February 2024

Introduction:
Deep medullary vein(DMV) thrombosis is a rare cause of neurological damage noted in both term and preterm infants. Although their incidence in children is not know, DMV thrombosis can occur isolated or in association with cerebral sinovenous thrombosis (CSVT). The spectrum of parenchymal radiological findings in DMV thrombosis includes edema and hemorrhage of variable extent. No clinical trials or definite treatment algorithms are available for DMV thrombosis in neonates. The choice of antithrombotic therapy is therefore based on the experience of the single centers or on indications extrapolated from available guidelines on CSVT.

Aims:
There are limited guidelines for the management of DMV thrombosis in literature. Recently published systematic review in neonates found a total of only 75 cases in literature. In none of these cases treatment options were described. We aim to present a single institute experience describing 3 cases of neonatal DMV thrombosis and different management methods.

Methods and findings:
Between July-August 2023, we prospectively studied 3 neonates with deep medullary vein thrombosis as evidenced by characteristic hemorrhage noted on MRI. For the 1st patient no anticoagulation was initially started given co-morbid conditions and critical illness. However, repeat imaging showed worsening of hemorrhage, thereby indicating progression of thrombosis resulting in venous hemorrhage. Pt was therefore stared on AC with LMWH. No worsening hemorrhage was noted thereafter. For the 2nd patient, AC was not started & no progression of thrombosis was noted. For the 3rd patient AC was started from a cardiac standpoint and no worsening in hemorrhage was noted. Observation: 1. Anticoagulation in patient with progression of DMV thrombosis did not worsen existing hemorrhage and prevented further propagation of clot. 2. No anticoagulation did not result in worsening of thrombosis and it likely self resolved in the absence of other comorbid conditions. 3. Anticoagulation used for a different indication did not worsen existing intraparenchymal hemorrhage. Next steps: 1. To conduct a retrospective chart review on a larger cohort of patients. This will help future studies and management options for this rare condition.
Abstract WP228: Vertebral Artery Configuration as a Risk Factor for Dissection in Children
Authors: Laheji Fiza K , Dowling Michael M , Braga Bruno P
Published: February 2024

Introduction:
Arterial ischemic strokes are estimated to occur in 1.2 to 8 per 100,000 children per year with 15-22% occurring in the posterior circulation. Vertebral artery dissection(VAD) is a known cause of posterior circulation ischemic stroke in approx 7% of cases.

Pediatric Bow Hunter syndrome, usually presents distinctively with VAD and stroke. It most commonly involves the V3 segment.

In 2021, Braga et all proposed a new protocol for management for children with spontaneous VAD.They noted 2 different configurations of the vertebral artery. In this study we go on the explore these different configurations further and their role in spontaneous VAD.

Aim & Hypothesis:
Two configurations of the vertebral artery at the V3 segment were observed. Type A and Type B depending on the angle of curvature of the V3 segment. Type A config. is more linear with > 110 degree of angulation. Type B config. is angulated with 2 < 110 degree angles.

We aim to investigate these configurations in patients without dissection vs those with vertebral artery dissection. We hypothesized that Type B configuration would be more prevalent in patients with spontaneous VAD.

Methods:
Retrospective chart review conducted at UTSW medical center. MRA/IR angiograms reviewed of 49 patients; 19 with spontaneous VAD and 30 with no vertebral pathology.

Results:
79% of the total dissected vessels(19/24) had configuration Type B and 20.83%(5/24) had configuration Type A. In the control group of 30 patients with no VAD, TypeB was present in 25.4%(13/51) and configuration A in 74.5% (38/51). Type B configuration had a statistically significant higher prevalence in V3 dissection group. (p=<0.001)

Conclusion:
Type B configuration of the V3 segment would warrant further investigation in the right setting.
Abstract WP238: Efficacy of Dual Antiplatelet Therapy After Lacunar versus Non-Lacunar Syndromes in the POINT Trial
Authors: Heidari Parisa , Seitz Alison , Liberman Ava , Navi Babak B , Kamel Hooman
Published: February 2024

Introduction:
About 20% of ischemic strokes are lacunar infarcts, the pathophysiology of which differs from that of other stroke etiological subtypes. The POINT trial demonstrated the efficacy of dual antiplatelet therapy (DAPT) for secondary stroke prevention in patients with minor ischemic stroke and high-risk TIA, but it remains unknown whether this benefit differed in lacunar versus non-lacunar strokes.

Method:
In a secondary analysis of POINT trial data, we compared the efficacy of DAPT in patients with an index lacunar syndrome versus not. A lacunar syndrome was defined based on common classic lacunar syndromes (e.g., pure motor hemiparesis, clumsy-hand dysarthria) and ascertained using subcomponents of the National Institutes of Health Stroke Scale documented at baseline. Our primary efficacy outcome was ischemic stroke and the safety outcome was intracranial hemorrhage. We used survival analysis and tests of interaction to compare the effect of DAPT between the lacunar and non-lacunar subgroups.

Result:
Among 4,881 patients enrolled in the study, 1,083 (22.1%) were classified as having an index lacunar syndrome. The effect of DAPT on the risk of ischemic stroke did not vary significantly after a lacunar syndrome (HR, 0.76; 95% CI, 0.52-1.09) versus after a non-lacunar syndrome (HR, 0.69; 95% CI, 0.50-0.95) (P value for interaction, 0.70). Similarly, the effect of DAPT on the risk of intracranial hemorrhage did not vary significantly after a lacunar syndrome (HR, 2.82; 95% CI, 0.29-27.1) versus after a non-lacunar syndrome (HR, 2.10; 95% CI, 0.63-6.99) (P for interaction, 0.82).

Conclusion:
In a post hoc secondary analysis of the POINT trial, we found no evidence of a lesser benefit of DAPT after a minor ischemic stroke or TIA in patients presenting with a lacunar syndrome compared to other stroke subtypes.