bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP69: Random Rater Sampling For Deep Learning Algorithm To Segment Acute Ischemic Stroke On Non-contrast Computed Tomography
Authors: Ostmeier Sophie , Verhaaren Benjamin F , Mahammedi Abdelkader , Christensen Soren , Albers Greg W , Lansberg Maarten G , Heit Jeremy J
Published: February 2023

Introduction:
The delineation of volume and location of acute ischemic brain tissue (AIBT) on Non-Contrast CT (NCCT) increases the efficiency of endovascular treatment decisions. However, the manual segmentation of the AIBT on NCCT is a challenging task and suffers from low inter-expert agreement. Whether supervised deep convolutional neural networks (CNN) are more accurate than expert raters remain to be determined, and the optimal ground truth segmentation of AIBT is unclear given the low inter-expert agreement. We hypothesized that randomly sampling ground truth segmentations of expert raters would enable the CNN to better approximate an accurate ground truth and increase performance.

Methods:
The data set consisted of 200 NCCT images (Figure 1a)) of acute ischemic stroke patients presenting within 6-16h and consenting to the DEFUSE3 trial.

Three experienced neuroradiologists manually segmented the AIBT (Figure 1b)1.-3.). The aggregated validation sets of 5-fold-cross-validation were used to compare the (i) average inter-expert agreement, the average performance of (ii) three individual CNNs trained on each rater and (iii) one CNN trained with random rater sampling.

Results:
(iii) Random rater sampling (Figure 1c)) lead to a CNN performance superior to (ii) the average performance of individually trained CNNs. The reliability of a CNN goes beyond the human inter-expert agreement (i) (Surface Dice at Tolerance 5mm: 0.88 versus 0.68 and 0.67, respectively; Table 1).

Conclusions:
The volume and location of AIBT on NCCT can reliably be segmented by a CNN. The agreement between a randomly chosen rater and the CNN predictions surpasses the inter-expert agreement (Table 1).
Abstract TP106: Outcomes Following Off-label Glyburide In Large Hemispheric Infarction: A Single-center Experience
Authors: Vigilante Nicholas , Patel Karan , Oak Solomon , Butler Miriam , Thon Jesse M , Siegler James E
Published: February 2023

Background:
One in 10 ischemic strokes are large hemispheric infarctions (LHI), half of which cause cerebral edema that can lead to significant mortality. Our center implemented a protocol using acute glyburide in patients with LHI to determine its safety and efficacy in reducing formation of cerebral edema.

Methods:
Consecutive adult patients at our center (10/2019-08/2021) with LHI who met criteria for the CHARM trial were treated with glyburide per an institutional protocol (2.5mg per nasogastric tube twice daily for 3 days) with multi-disciplinary oversight. Unadjusted logistic regression was used to estimate odds of a favorable shift in 90-day modified Rankin Scale (mRS), with adjustment for age, pre-stroke mRS, National Institutes of Health Stroke Scale (NIHSS) and large vessel occlusion (LVO). Propensity-score matching was used to model shift in 90-day mRS. Safety events were also assessed.

Results:
Of 1684 stroke patients treated at our center, 95 met criteria for CHARM and were included, among whom 21 completed the glyburide protocol (28 attempted) and 67 received standard-of-care (SOC); 34 patients were propensity-matched (nglyburide=17). Compared to SOC (n=67), patients treated with glyburide (n=21) had similar pre-stroke mRS, NIHSS, and LVOs, but were younger (median 61y vs. 67y, p<0.01). Glyburide was not associated with a favorable shift in 90-day mRS in unadjusted (OR 1.40, 95%CI 0.51-3.88) or adjusted regression (OR 0.71, 95%CI 0.17-2.94), or following propensity score matching (OR 1.39, 95%CI 0.32-6.07). There was no significant reduction in midline shift in unadjusted, adjusted, or propensity score-matched models (p>0.05). Two patients required D50 rescue, and 1 did not complete the protocol due to recurrent hypoglycemia.

Conclusions:
In this single center analysis, glyburide was found to have a low risk of hypoglycemic events. Despite the small sample size, there was no signal of better clinical or imaging outcomes in treated patients.
Abstract TP109: The Impact Of Atrial Fibrillation (Afib) On The Discharge Disposition In Patients Who Received Acute Stroke Intervention Therapies? Results From A Large Health System In Six Western States Of The United States
Authors: Bavarsad Shahripour Reza , Marginean Horia , Corless Leslie , Singh Tarvinder , Loh Yince , Lowenkopf Ted J , Lesko Alexandra C , Guerrero Adrieanne , Pirastehfar Mohsen , Tarpley Jason W
Published: February 2023

Introduction:
Limited studies indicate patients with acute ischemic stroke (AIS) due to atrial fibrillation (Afib) may not respond as well to intravenous thrombolysis (IVT) compared to those without Afib, resulting in poor outcomes. This study compares the length of stay (LOS) at the hospital and discharge disposition (home, inpatient rehabilitation, nursing home facility, or death) in patients receiving acute stroke treatment with IVT and/or thrombectomy (EVT) in Afib and non-Afib groups.

Methods:
Data from a multi-state health system’s stroke registry for patients who received acute stroke treatment and were discharged between 2018 and 2022 were used. Patients were stratified into three groups: 1, EVT only with or without history of Afib; 2, IVT plus EVT with or without history of Afib; 3, IVT only with or without history of Afib.Multivariable mixed-effect regressions were performed to evaluate if patients with Afib had an effect on LOS or discharge disposition within the three treatment groups adjusting for patient age, sex, race and ethnicity, NIHSS on admission, blood glucose on admission, SBP on admission, and history of diabetes, CAD/prior MI, carotid stenosis, smoking, dyslipidemia, heart failure, being overweight, or renal insufficiency.

Results:
Among patients with AIS, the median age at arrival was 72 years, 51% male, 70% white, and non-Hispanic; the median NIH Stroke scale was 9.Discharge disposition and LOS were assessed in a cohort of 7820 patients: In group 1(EVT, n: 2388): 37.4% had Afib and 53.3% discharged home, median LOS 5.42 days. In group 2(IVT/EVT, n: 978): 28.5% had Afib and 58.8% discharged home , median LOS 4.25 days. Among group 3(IVT, n: 4454) 14.4% had Afib and 67.8% discharged home, median LOS 2.90 days. After adjustment, there was no association between Afib and either outcome in the three treatment groups.

Conclusions:
The history of Afib in a patient with AIS does not have a significant negative impact on the LOS or discharge disposition.
Abstract TP114: Stroke Mimics: Uncovering The Truth In The History
Authors: Emmerson Danison , Miller Ethan , Elmashad Ahmed , Tunguturi Ajay , Nouh Amre M
Published: February 2023

Background:
Inpatient acute stroke identification may be challenging given the complexity related to both concomitant and comorbid illness. Rapid and accurate diagnosis requires a skilled clinician to discern acute stroke patients from other mimics such as hypoglycemia, hemiplegic migraine, post-ictal paresis, relapse of a demyelinating disease, or recrudescence of prior stroke.

Hypothesis:
Negative predictors of acute stroke can be identified in inpatients with inpatient stroke alerts.

Methods:
IRB approved, retrospective analysis of prospectively obtained data was performed for all inpatient stroke alerts between March 2017 and May 2020. Patients with MRI confirmed diagnosis of acute stroke were compared to all others. Univariant analysis was performed with Wilcoxon Ranked Sum test used for non-parametric data to identify risk factors to include in the logistic regression (p<0.05).

Results:
674 inpatient stroke alerts resulted in 223 (33%) acute strokes and 451 (67%) non-stroke diagnoses. For stroke vs. non-stroke patients, median age 70.5 vs. 68.6 years, last seen well 77.5 vs. 65.0 minutes (p= 0.030), NIHSS score 10 vs. 4 (p<0.001). In the non-stroke group, 156 (23%) had a witnessed seizure documented during the alert compared to 0% in the stroke group. Negative predictors of stroke included previous diagnosis of epilepsy (0.302 odds, P<0.007), anti-seizure drug (ASDs) prescribed prior to (1.662 odds, p<0.001) or at time of the alert (2.479 odds), and previous EEG(P<0.001).

Conclusions:
It is imperative to consider post-ictal paresis as a differential diagnosis when assessing patients who present as stroke alerts. The administration of thrombolytics in stroke mimics is not without harm and incorrect diagnosis will delay appropriate treatment. Witnessed seizure at time of alert, history of epilepsy diagnosis, use of ASD prior to or at the time of the alert, and prior EEG findings may serve as a tool to help differentiate between acute stroke and seizure diagnosis. Further study will be aimed at identifying alternative pathways for rapid assessment of patients with acute changes in neurologic exam.
Abstract TP118: Brain Iron Quantification By MRI In Normal Human Subjects And Contra-lesional Hemisphere Of Intraparenchymal Hemorrhage (IPH) Patients
Authors: Lin Leanne Y , Chaudhary Neeraj , pandey aditya
Published: February 2023

Introduction:
Human cadaveric studies have correlated higher transverse relaxation rate (R2*) to higher tissue Fe concentrations. These methods enable non-invasive brain tissue Fe quantification after IPH. This study tested these methods on live human IPH patients vs. normal subjects to assess using the contra-lesional cerebral hemisphere as an internal control for future longitudinal tissue Fe quantification studies.

Methods:
Normal and IPH subjects underwent MRI on a 3T clinical scanner with a 32-channel head coil. Scans included anatomic T1- and T2-weighted images and a 3D gradient 8-echo sequence. Seven regions on the contra-lesional hemisphere were segmented using registered T1 and gradient-echo images. R2* maps were generated and the mean values per region were compared to identical regions in normal subjects using a T-test with Bonferroni correction (corrected p = p * 7).

Results:
14 IPH patients, aged 18-85, and 10 control subjects, aged 35-73, underwent MRI scanning. Mean R2* varied from 17.8-40.8 Hz in IPH subjects and 19.5-38.4 Hz in normal subjects. There was a significant difference in the mean R2* values in the centrum semiovale (p=2.9e-5). The other regions demonstrate no significant differences in mean R2* values, as shown in the figure.

Conclusion:
In the contra-lesional centrum semiovale, the average R2* values of IPH patients correlate to lower Fe concentrations compared to controls. Upon further review of anatomic T1- and T2- weighted images, we found that the IPH patients had more white matter T2-hyperintense foci likely accounted for by underlying small vessel disease. In the other brain regions, the contralateral cerebral hemisphere of IPH subjects had R2* values not significantly different from controls. This suggests the Fe released from a hematoma does not cross into the contra-lesional hemisphere, which may be used as an internal control in future longitudinal IPH studies.
Abstract TP123: Natural Rate Of Hematoma And Edema Resolution In Patients With Intracerebral Hemorrhage Using Serial Magnetic Resonance Imaging
Authors: Solberg Spencer , Boren Seth , Gonzales Nicole R , Savitz Sean I , Aronowski Jaroslaw A , Haque Muhammad E , Green Charles
Published: February 2023

Objective:
Serially measure the rate of hematoma volume (HV) and edema volume (EV) resolution in patients with acute-to-early chronic ICH

Background:
After ICH, the primary cause of brain injury is the mechanical force from the compression of the brain tissue. The secondary damage involves (bio)chemical injury produced by the toxicity of components of extravasated blood, which directly compromises surrounding tissue by oxidative stress, cell death, neuroinflammation, and brain edema. There is very little known about the rate of HV and EV resolution within one month of ictus.

Methods:
Twelves patients, a placebo sub-cohort of a previous clinical trial, were serially imaged on day-1, 14, and 28 of initial ictus. Anatomical (FLAIR, T1W, and T2W) images were obtained on a 3T MRI system. HV and EV were segmented using semiautomated seed growing algorithm. The prediction of HV and EV resolution rate was calculated using the Bayesian model and compared across the different time points.

Results:
There were 7M/5F with the average age of 57 ± 9y. The baseline average HV/NIHSS 22,998 mm
3
/11. All patients with deep ICH and 6 extended to IVH. The multilevel Bayesian analysis showed the rate of HV resolution -327.90 mm
3
(95% CrI = -475.37- -181.86; Posterior Probability b < 0 ≥ 0.99) with 14 days acceleration of -17.67 mm
3
(95% CrI = -35.89- 1.21; Posterior Probability b < 0 = 0.97). The rate of EV resolution -341.44 mm
3
(95% CrI = -736.32- 60.98; Posterior Probability b < 0 = 0.96) with 14 days acceleration -34.63 mm
3
(95% CrI = -85.47- 16.61; Posterior Probability b < 0 = 0.91). Overall the decrease in HV over time was an offsetting deceleration which increases over time. The overall trend of HV resolution is shown in Fig-1

Conclusion:
There was a high variance in the rate of HV and EV resolution, but overall all the patients exhibited a similar trend. The rates of HV and EV resolution can help us provide optimal patient care.
Abstract TP124: Irraflow® Device (ventricular Irrigation And Drainage System) Achieves Optimal Clearance Of Intraventricular Hemorrhage (IVH)
Authors: Wilson Jennifer , Bhinder Kanwar , Male Shailesh , Dalyai Richard , Griswold Jennifer , Karim Nurose , Bhinder Vikram
Published: February 2023

Introduction:
IVH clearance of more than 80% with intraventricular fibrinolysis administered via a conventional external ventricular drain (EVD) is associated with improvements in outcomes; however, 80% IVH clearance is difficult to achieve. The IRRAflow® device offers fluid irrigation and drainage in a unique system that is designed to provide efficient drainage and clearance of hemorrhage, which may provide advantages over a conventional EVD. The purpose of this study is to evaluate the radiographic findings and outcomes of patients with IVH associated with intracranial hemorrhage (ICH) or subarachnoid hemorrhage (SAH) who received treatment with the IRRAFlow® device from April 1, 2021, to May 1, 2022.

Methods:
This was a single center, retrospective review. The primary outcome was change in IVH volume which assessed by modified Graeb Scale (mGS). All endpoints were analyzed using descriptive statistics.

Results:
Twelve patients were identified during the study period. Four patients were not included in the analysis due to withdrawal of care (n=2) or severe stroke causing death before completion of treatment (n=2). Of the eight patients included in the study, two had IVH associated with SAH, and six had IVH associated with ICH. Four patients received intrathecal boluses of alteplase, and three patients also had a traditional EVD placed in additional to the ventricular flow device. Seven patients had a pre-treatment mGS greater than or equal to 5, and two patients had a pre-treatment mGS of 4. The mean (+/- SD) pre-treatment mGS was 14 (+/- 8), and post-treatment mGS was 2 (+/- 3). The mean (+/- SD) volume clearance, which was calculated using the mGS, was 92% (+/- 12%). All patients had a modified Rankin scale (mRS) of 4 prior to treatment. Mean (+/- SD) mRS was 3 (+/- 1) at post-discharge follow up. All patients achieved IVH clearance, with third and fourth ventricle clearance, except for one patient who removed the device prior to completion of therapy. None of the patients required ventriculoperitoneal shunt placement or died. One patient developed ventriculitis as a complication.

Conclusion:
In conclusion, the IRRAFlow® device was successful in achieving goal IVH clearance (mGS less than 5) in all patients, which has been associated with improved outcomes.
Abstract TP125: Relationships Of Female Sex With Viscoelastic Hemostatic Assay Coagulation Characteristics After Intracerebral Hemorrhage
Authors: Mitchell Amanda , Heinonen Gregory , Carvalho Poyraz Fernanda , Cottarelli Azzurra , Mao Eric , Ghoshal Shivani , Agarwal Sachin , Park Soojin , Claassen Jan , Connolly Edward , Roh David
Published: February 2023

Introduction:
There are described differences in coagulation between females and males. Specifically, female sex is associated with greater platelet activation and stronger clotting characteristics. It is unclear whether there are relevant coagulation differences identifiable between female and male patients suffering from intracerebral hemorrhage (ICH).

Hypothesis:
Female sex will be associated with stronger clotting characteristics on whole blood viscoelastic hemostatic assay testing.

Methods:
Spontaneous ICH patients admitted and enrolled into a prospective observational ICH cohort study between 2009-2020 and who received baseline viscoelastic hemostatic assay testing (Rotational Thromboelastometry: ROTEM) were assessed. Patients with prior anticoagulant use, patients receiving hemorrhage control therapies prior to ROTEM, and secondary etiologies of ICH were excluded from the analysis. Female sex was assessed as the primary exposure variable. The following ROTEM clotting parameters were assessed as the outcome: Coagulation Time (CT) and Maximum Clot Firmness (MCF). We assessed relationships of female sex with these separate ROTEM parameters using multivariable linear regression analyses after adjusting for relevant covariates.

Results:
Of 57 ICH patients included for analyses, mean age was 65 (SD 14.1), 47% were female, and the median ICH volume was 20.6 mL (IQR 10.1-43.3). There were no baseline intergroup sex differences in demographics, age, or ICH characteristics. Female sex was associated with increased EXTEM MCF (ß 0.323, p<0.05), signifying greater clotting strength, after adjusting for age, race, baseline hematoma volume, and ICH location. Female sex was not associated with other ROTEM parameters.

Conclusions:
We identified that female sex was associated with stronger clotting characteristics on ROTEM viscoelastic testing. Further work is required to clarify the clinical significance of these findings and their potential specific impacts on radiographic, complication, and clinical outcomes after ICH.
Abstract TP136: Thrombectomy Outcomes In Patients With Elevated Modified Rankin Scores
Authors: Johnson Melissa Martinez , Do Rachel , Williams Dena , Wang Michael , Huang David Y , Johnson Matthew , Wilson Susan E , Beckwith Anne , Ho James
Published: February 2023

Introduction:
The modified Rankin Scale (mRS) is a disability outcome measure often utilized in mechanical thrombectomy (MT) trials. An mRS of 0-2 at 90 days post intervention has been deemed a good functional outcome. Some trials required a pre-stroke mRS 0-1, while others included patients in the 0-2 range. None of the major trials enrolled patients with baseline mRS greater than 2, and there have been limited data/review of outcomes in these patients with inconclusive results. We conducted an institutional retrospective review to evaluate the proportion of patients who underwent successful MT (TICI 2b or higher) and remained at their baseline mRS. This will enable us to more appropriately evaluate if patients with higher baseline mRS should be considered for intervention.

Methods:
We conducted a retrospective review of all patients who underwent successful MT at our institution through 2021. Utilizing descriptive statistics in SAS, we specifically evaluated the number of patients who remained at their baseline mRS post intervention at each level.

Results:
412 patients were included (259 patients with mRS 0, 66 with mRS 1, 36 with mRS 2, 29 with mRS 3, 16 with mRS 4, and 6 with mRS 5). Of the 412, 60 patients remained at their pre-stroke mRS at 90-days post intervention (14.29 % at mRS 0, 15.15% at 1, 16.67% at 2, 17.24% at 5, 0% at 4, and 33.33% at 5).

Conclusion:
Our data suggests that patients with higher baseline mRS, specifically mRS 3, may benefit from intervention with MT to maintain their functional ability. The proportion of patients who remained at their pre-stroke mRS was higher in the subgroup with mRS 3 comparative to mRS of 0 or 1; however, there were fewer patients overall. Our institutional data also highlights that patients with baseline mRS 3 did similarly well in maintaining their premorbid functional ability as those with mRS 2 (36 vs 29 patients, 17% in each group). This ultimately suggests that patients with baseline mRS 3 should be considered for MT. There are too few patients with baseline mRS 4 and 5 in our study, and given there is already significant disability in these subgroups, it would be difficult to conclude currently that these patients should undergo intervention.
Abstract TP141: The Modified Dwi-aspects As A New Method Closer To The True Infarct Volume In Acute Stroke
Authors: Suzuki Kentaro , Kimura Ryutaro , Nishi Yuji , Sakamoto Yuki , Katano Takehiro , Saito Tomonari , Aoki Junya , Nishiyama Yasuhiro , Kimura Kazumi
Published: February 2023

Objective:
The DWI-Alberta Stroke Program Early CT Score (DWI-ASPECTS) assessed using diffusion-weighted imaging can estimate the infarct volume in acute stroke. However, for 10 parts of DWI-ASPECTS, a small lesion as well as a large lesion are treated equally as a one score. Thus, if the lesions are small, conventional DWI-ASPECTS might overestimate the true infarct volume. We created the modified DWI-ASPECTS score as a new method closer to the true infarct volume, and studied which better conventional and modified DWI-ASPECTS to predict the true infarct core volume.

Methods:
Stroke patients treated with mechanical thrombectomy in our hospital from January 1, 2013 to December 31, 2019 were enrolled. The modified DWI-ASPECTS was defined to one point if more than half of one-part area of M1-6 have high intensity, and no point if less than half of one-part area of M1-6 have high intensity. The ischemic core volume was measured using 3-dimen-sional Slicer 4.10.2, an open source software platform.

Results:
297 cases were enrolled (age; 75 [67-82], 195 [65%] men and initial NIHSS score 15 [9-21]). Ischemic core volume was 11 [3-37] ml. Score of conventional and modified DWI-ASPECTS were 8 [7-9] and 7 [5-9], respectively. The correlation coefficient (r) between ischemic core volume and score of conventional and modified DWI-ASPECTS were 0.773, and 0.832, respectively. Therefore, modified DWI-ASPECTS was superior to conventional DWI-ASPECTS to predict the infarct core volume.

Conclusions:
The modified DWI-ASPECTS should be more effective to predict the true infarct core volume compared to conventional DWI-ASPECTS in acute stroke.
Abstract TP152: Association Of 24-hour Blood Pressure Parameters Post-thrombectomy With Functional Outcomes In Anemic And Non-Anemic Patients
Authors: Nisar Taha , Tofade Toluwalase , Shaulov Shaul , Shapouran Sara , Abu-hadid Osama , Khandelwal Priyank
Published: February 2023

Introduction:
Higher blood pressure (BP) is thought to be detrimental in patients who undergo mechanical thrombectomy (MT), however, the impact of BP post-MT based on comorbidities like anemia has not been well studied. We aim to determine the association of 24-h post-MT BP parameters with clinical outcomes depending on the presenting anemia status.

Methods:
We conducted a retrospective chart review of patients who underwent MT at a comprehensive stroke center from 7/2014 to 12/2020. Patients were dichotomized into anemic and non-anemic groups based on the World Health Organization’s definition of anemia [hemoglobin <12.0 g/dL in women and <13.0 g/dL in men]. We performed a binary logistic regression analysis controlling for baseline parameters, with the 24-h post-MT BP parameters as predictors. The outcome was functional dependence (3-month mRS ≥2).

Results:
220 patients met the inclusion criteria. 158 (71.82%) patients had functional dependence at 3-months. In the multivariable analysis, the parameters of a higher mean SBP (132.9±11.94 vs.126.52±13.3; OR, 1.04; 95% CI, 1.01-1.08; P 0.043), a higher maximum SBP (159.05±13.43 vs153.11±19.07; OR, 1.04; 95% CI, 1.01-1.07; P 0.04) and a higher maximum MAP (115.26±11.73 vs.109.37±12.51; OR, 1.04; 95% CI, 1.01-1.08; P 0.042) were significantly associated with functional dependence in patients without anemia. For patients with anemia, there was no association between 24-hour BP Parameters post-MT and functional dependence.

Conclusion:
In our study, higher BP parameters were associated with worse outcomes in patients without anemia, however, this effect was not found in patients with anemia. Anemia induces a relative hypoxic state in target tissue in the event of an increase in metabolic demand such as stroke. Higher BP post-MT can potentially promote perfusion and thus is not associated with worse outcomes in anemic patients post-MT, whereas in non-anemic patients it potentially leads to reperfusion injury.
Abstract TP159: Association Of Lesion Characteristics And Neurological Outcomes In Neonatal Arterial Ischemic Stroke Patients
Authors: Domi Trish , Li Janet , Walker Kirstin , Robertson Amanda , Dlamini Nomazulu
Published: February 2023

Background:
Neonatal arterial ischemic stroke (NAIS) occurs as a result of an acute focal cerebral arterial infarction between birth and 28 days of life in nearly 1:2500 live births. As there are few studies examining the relationship between NAIS lesion characteristics and clinical outcomes, this study aims to determine if lesion volume and lesion location are associated with abnormal neurological outcomes in NAIS.

Methods:
Semi-automated lesion segmentation of co-registered multi-modal images was conducted using ITK-SNAP. Semi-automated lesion segmentations with manual corrections were performed using ITK-SNAP software. Lesion volumes were corrected for head size by dividing lesion volumes by total intracranial volume, and correlated (using Kendall's Tau-b [τ
b
]) with neurological outcome that was assessed with the Pediatric Stroke Outcome Measure (PSOM).

Results:
Participants included N=20 NAIS patients (mean [M] weeks gestation=39.5, +/-1.64; 55% male, 70% single infarct, 75% left-sided lesions). Outcome was assessed an average of 312, +/-7.6 days post-stroke. Neurological deficits were present in 50% (with seizures in 85%) at time of stroke, and infarct locations most commonly involved supratentorial cortical structures (75%), however none were correlated with outcome. Larger lesion volumes (M=5.35 mm
3
, +/-0.069) were correlated with poor outcome (τ
b
=.444, p=0.02).

Conclusion:
We found larger lesion volume to be associated with atypical clinical outcomes following NAIS. Further analysis is in progress that include changes over time in lesion characteristics and outcome. These results demonstrate a need for better characterize the relationship between lesion characteristics and outcomes in NAIS.
Abstract TP16: Association Between Sleep Duration And Cognition Among Us Stroke Survivors.
Authors: Lekoubou Alain , Osei-Bonsu Wendy , Markovic Daniela , Ovbiagele Bruce , Towfighi Amytis
Published: February 2023

Rationale:
Sleep duration has been associated with an increased risk of stroke. Cognitive impairments are frequent complications of stroke, particularly among elderly stroke survivors; However, there is a dearth of information on the link between sleep duration and cognitive impairment among stroke survivors. The current analysis aims at filling this gap.

Methods:
We used the National Health and Nutrition Examination Survey (NHANES) 2011-2012 to examine the association between sleep duration and cognitive impairment among elderly (60 years and above) stroke survivors. Sleep duration was divided into short (<7 hours), normal (7-8 hours), and long (>8 hours). We applied linear regression models to compare mean scores of pre-specified cognitive test scores, including the Consortium to Establish a Registry for Alzheimer’s Disease total score (CERAD total); CERAD: Score Trial 1 Recall; CERAD: Score Trial 2 Recall; CERAD: Score Trial 3 Recall; CERAD: Score Delayed Recall; Animal Fluency: Score Total, and Digit Symbol Score across sleep duration, accounting for complex survey design, including weighting, clustering and stratification, and adjusting for age, sex, race/ethnicity, income, BMI, diabetes and hypertension.

Results:
Out of a total of 240 (unweighted) stroke participants, 58% were women. Stroke survivors with short sleep duration were more likely to be non-white compared to those with normal sleep duration (p-value <0.0001). Compared to normal sleep duration, long sleep duration was associated with lower mean CERAD total score (22.3 vs. 18.3, p = 0.014) and Digit Symbol score (35.8 vs. 29.4, p = 0.024). Compared to short sleep duration, long sleep duration was associated with smaller mean CERAD total score (22.761 vs. 18.331, p = 0.009) and Digit Symbol score (36.530 vs. 29.424, p = 0.041). There were no associations between short sleep duration and cognitive scores.

Conclusion:
In this retrospective analysis of elderly stroke survivors, long sleep duration (vs normal and short) were independently associated with poor cognitive scores. There was no association between short sleep duration and cognitive scores
Abstract TP164: Impact Of Baseline Carotid Intima-media Thickness On All Causes And Cardiovascular Disease Mortalities In A General Urban Population: The Suita Study
Authors: Wada Shinichi , Kokubo Yoshihiro , Yoshimura Sohei , Teramoto Masayuki , Kashima Rena , Koga Masatoshi
Published: February 2023

Purpose:
This study aimed to explore the association between carotid intima-media thickness (IMT) and the Suita Risk Score for cardiovascular events and all-cause and cause-specific death.

Methods:
We studied 4,870 Japanese individuals (mean age 55.0±12.2 years, without CVD at the baseline; women 53.9%) who completed a baseline survey and carotid atherosclerosis in the Suita and were then followed for 14.8 years of the median. Carotid IMT was evaluated by high-resolution ultrasonography with atherosclerotic indexes of IMT in the common carotid artery (CCA) and carotid artery bulb (Bulb). We defined Mean CIMT as the mean of the IMT of the proximal and distal walls for both sides of the CCA on a longitudinal scan at a point 10 mm proximal from the beginning of the dilation of each carotid artery bifurcation. The maximum IMT in the CCA (max-CIMT) and the entire area (max-IMT) were defined as the maximum measurable IMT in the scanned CCA and the entire scanned carotid artery areas for both sides. The risks of all-cause mortality across carotid IMT were compared using Cox proportional-hazards models adjusting for the Suita risk score. The 95% CIs of the C-statistic was estimated using 200 bootstrap samples. Similarly, the standard error for the difference in C-statistic between each model was estimated from the bootstrap samples and used to calculate a P value for the difference.

Results:
We observed 923 deaths during 14.8 years as a median. The fourth quartiles of mean CIMT observed increased risks of all causes of mortalities and CVD mortality (hazard ratio (HR)=2.65, 95%CIs,1.93-3.63; HR=4.89, 95%CIs,1.88-12.72), max-CIMT (HR=1.99, 95%CIs,1.47-2.70; HR=2.92, 95%CIs, 1.21-7.06), and max-IMT (HR=2.13, 95%CIs,1.63-2.78; HR=2.69, 95%CIs, 1.30-5.58), respectively, compared to the first quartiles of then. C-statistic significantly improved by adding the fourth quartiles of mean CIMT and max-IMT to the Suita risk score for all-cause death (+0.003, 95%CIs, 0.0002-0.005, P=0.03 and +0.006, 95%CIs, 0.002-0.010, P<0.01; respectively), although not significantly improved for CVD mortalities.

Conclusion:
Additional assessment of carotid IMT to the Suita risk score may be helpful to improve the predictive ability for all causes of mortalities, not for CVD mortalities.
Abstract TP165: Missed Diagnosis In Cervical Artery Dissection: A Single Center Cohort Study
Authors: Penckofer Mary , Siegler James , Vigilante Nicholas , Kamen Scott , Zhang Linda , Frost Emma , Koneru Manisha , Oak Solomon , Oliveira Renato
Published: February 2023

Background:
Misdiagnosis in Cervical Artery Dissection (CAD) is thought to be uncommon but presenting symptoms and risk factors for misdiagnosis are not well defined.

Methods:
A nested cohort of patients with acute nontraumatic CAD were identified from a single center (2015-2021). Patients with CAD originally misdiagnosed (visiting a medical provider within 30 days for symptoms related to CAD without diagnosis of CAD) were compared against those diagnosed at presentation using descriptive statistics and unadjusted logistic regression.

Results:
Of the 52 included patients, 25 (48%) had a stroke at diagnosis, and 14 (27%) were misdiagnosed as non-CAD. Patients misdiagnosed had less severe pre-existing disability (median modified Rankin Scale and interquartile range [IQR], 0 [0-1] vs. 1 [0-1]) and were non-significantly younger (median 45 [35-68] vs. 53 [40-65], p=0.35). There was no difference in the distribution of vascular risk factors between groups. The most common presenting symptoms in misdiagnosed patients, such as focal deficits (43% vs. 42%, p=0.96) and headache (36% vs. 21%, p=0.78) were not associated with misdiagnosis. Less frequent symptoms like Horner’s syndrome (21% vs. 5%, p=0.11), neck pain (21% vs. 8%, p=0.33), and dizziness (14% vs. 5%, p=0.29) were non-significantly more common among patients with misdiagnoses.

Conclusions:
One-quarter of patients with nontraumatic CAD were misdiagnosed at first presentation. Misdiagnoses may be more common in younger persons with less pre-existing disability, and those with nonspecific symptoms such as dizziness and neck pain. Larger studies are needed to provide more precision in estimates of association.
Abstract TP168: Stroke Risk Among Those With Prior Healthcare Associated Infections: A Case Control Study
Authors: Vollmer Brandi , Larson Elaine , Elkind Mitchell , Boehme Amelia K
Published: February 2023

Introduction:
Younger age groups demonstrate greater heterogeneity in stroke etiology compared to the older stroke population. Identifying novel risk factors in this population is a high priority.

Methods:
Our study utilized patient data from three urban Manhattan hospitals and one community hospital outside of Manhattan. Cases were adults with a stoke admission. Controls were adults with a trauma or orthopedic admission randomly matched 2:1 to cases on date of admission. Odds of stroke following an infection during the prior year as compared to those with no infection was assessed using unadjusted logistic regression and as a time-varying analysis using unadjusted and adjusted generalized estimating equations controlling for time, age, sex, race, hypertension, diabetes, renal failure

Results:
Our study included 8,983 stroke cases and 17,966 matched controls with a mean age of 68.9 and 61.2 years, respectively. Of cases 50.6% were female. 28.8% were non-Hispanic white, 31.4% had diabetes, 61.7% had hypertension and 21.7% had renal failure. Of controls, 50.1% were female, 30.7% were non-Hispanic white, 15.3% had diabetes, 36.1% had hypertension and 15.1% had renal failure. Within the 1 year prior, 21.5% of cases and 14.5% of controls had an infection. Those with an infection in the year prior had increased odds of stroke when compared to those with no infection (Table 1) with the greatest effect size seen in those ≤45 years old.

Conclusions:
Odds of stroke increases following a hospital-acquired infection, particularly in the young population. Odds by type of infection will be presented.
Abstract TP171: Impacts Of Left Atrial Size On The Short-term And Long-term Outcomes After Acute Ischemic Stroke
Authors: Chen Chih-Hao , Tang Sung-Chun , Jeng Jiann S
Published: February 2023

Objectives:
To investigate whether the left atrial diameter (LAD) was associated with stroke severity, outcome, long-term risk of stroke recurrence and mortality in patients with acute ischemic stroke.

Methods:
This study included acute ischemic stroke patients in the National Taiwan University Hospital Stroke Registry from 2015 to 2021. LAD was measured by transthoracic echocardiography and was divided by body surface area (indexed LAD) for standardization. Patients were further classified into normal (<2.3 cm/m
2
), mildly (2.4-2.6), moderately (2.7-2.9), and severely (≥3.0) abnormal LAD. Short- term outcomes included stroke severity, stroke-in-evolution, and 3-month modified Rankin Scale (mRS), while long-term outcomes include recurrent ischemic stroke and mortality.

Results:
In total, 3952 patients (mean age 69.7±14.1, 43% female) were enrolled. The mean indexed LAD was 2.3±0.6 cm/m
2
. Patients in the abnormal LAD groups were older, had more female, higher NIHSS, more cardioembolic stroke, more likely to received reperfusion therapy, had higher proportion of stroke-in-evolution and higher 3-month mRS. In adjusted analyses, increased indexed LAD (per 1 cm/m
2
) was associated with functional independence (mRS 0-2) at 3 months (odds ratio (OR) 1.59, 95% CI 1.28-1.98). During the follow-up of 3.12±2.16 years, 413 patients had recurrent ischemic stroke and 747 patients died. Increased indexed LAD was associated with mortality (hazard ratio (HR) 1.21, 95% CI 1.04-1.40), but not recurrent ischemic stroke (HR 1.07, 95% CI 0.86-1.32). In the cryptogenic stroke subgroup, severely abnormal LAD was associated with recurrent ischemic stroke (HR 2.69, 95% CI 1.23-5.88). In the AF subgroup, patients with pre-stroke oral anticoagulant use had larger indexed LAD (2.9±0.6 vs 2.6±0.6), but they had lower initial NIHSS at (8 vs 10) and were more likely to achieve functional independence (OR 1.55, 95% CI 1.08-2.24).

Conclusion:
In patients with acute ischemic stroke, left atrial enlargement is associated with higher probability of functional independence at 3 months, but higher risk of long-term mortality. Despite having larger left atrial size, pre-stroke oral anticoagulant use might be associated with better outcome in patients with atrial fibrillation.
Abstract TP175: Age And Malignancy Associated With Positive Antiphospholipid Antibody Testing And Diagnosis In Embolic Stroke Of Undetermined Source Patients: A Retrospective Cohort Study
Authors: Liu Michael , Griffin Kim , Harahsheh Ehab , Shahid Adnan , Scharf Eugene L
Published: February 2023

Introduction:
Embolic stroke of undetermined source (ESUS) is a clinical paradigm that helps to classify and lead investigations into cryptogenic stroke. Diagnostic evaluation of ESUS involves investigating several potential etiologies of stroke. One such etiology includes antiphospholipid syndrome (APLS), a syndrome known to cause hypercoagulability. Clinical characteristics of primary APLS in ESUS have not been described.

Methods:
This is an IRB approved, retrospective study including patients from 2015-2020 who were seen at Mayo Clinic, were diagnosed with ESUS, and had APLS testing (anti-cardiolipin, beta-2 glycoprotein, or lupus anticoagulant). Baseline characteristics and radiographic features were collected and compared between patients who were and were not diagnosed with APLS, as well as between patients who were and were not APLS antibody positive.

Results:
Our study included 206 patients. Positive APLS antibody testing was seen in 21 (10%) patients. Of those patients, 8 (4%) received a formal diagnosis of APLS. Compared to controls, patients with positive APLS antibodies as well as those diagnosed with APLS were more likely to have a history of cancer (20 [11%] APLS antibody negative vs 7 [33%] APLS antibody positive p=0.004) (23 [12%] APLS diagnosis negative vs 4 [50%] APLS diagnosis p=0.002). Mean age in primary APLS was greater, 57 years old APLS antibody negative vs 69 years old APLS antibody positive (p<0.001) and 58 years old APLS diagnosis negative vs 75 years old APLS diagnosis (p=0.001) (Table 1). Regressions analyses examining infarct topography and rate of hemorrhagic transformation were non-significant between groups (p>0.1)

Conclusion:
APLS presenting as ESUS is associated with older age and history of malignancy. We speculate this finding may underscore the need to consider hypercoagulable conditions more broadly in stroke evaluations of older populations. Larger cohorts and longer follow up will be required to validate this observation.
Abstract TP189: Identifying Stroke Patients At Risk For Cognitive Impairment And Dementia Using Electronic Health Record Data And Machine Learning
Authors: Hasan S M Shafiul , Su Tongli , Saurman Jessica , Nahab Fadi B , Hu Xiao
Published: February 2023

Background:
Stroke patients are at high risk of developing cognitive impairment and dementia. Failure to identify cognitive impairment in time could hasten the progression of dementia and impact the rehabilitation plan. Therefore, a reliable method is needed to determine a stroke survivor’s susceptibility to post-stroke cognitive impairment and dementia (PSCID).

Method:
We conducted a retrospective cohort study of cryptogenic stroke (CS) patients from January 1, 2017, to February 28, 2022, using EHR data to query for PSCID onset. A machine learning (ML) model was created to forecast the occurrence of PSCID during follow-up. The features used in the model included elements from EHR that were found to be associated with PSCID in other studies, including sociodemographic, medical, and mental morbidities. Logistic Regression, Random Forest (RF) Classifier, and Gradient Boosting are examples of ML algorithms that were used. The final model used RF Classifier due to its superior performance.

Results:
Of 390 CS patients (62±16 years, 56.4% male) included in the analysis, 110 (28.2%) had documented PSCID in EHR following the initial stroke. We evaluated our model in a repeated (n=100) 10-fold cross validation scheme and used Synthetic Minority Oversampling Technique (SMOTE) to compensate for class imbalance. We identified the most informative ten features using an Extra Tree classifier, which are age, transient ischemic attack, sex, smoking, diabetes, hypertension, atherosclerosis, anemia, and atrial fibrillation. Using these features, our RF classifier reached a performance of 71.2±6.5% accuracy, 70±4.9% precision, 75±12% recall, and 0.777±0.082 AUC.

Conclusion:
Our model could predict the CS patients at risk for PSCID with reasonable accuracy using only ten features. Future work should involve a larger cohort along with more advanced machine learning algorithms to enhance the prediction performance.
Abstract TP201: The Role Cardiovascular And Non-cardiovascular Risk Factors In The Development Of Strokes Among Young Adults
Authors: Leppert Michelle H , Poisson Sharon N , Scarbro Sharon , Suresh Krithika , Lisabeth Lynda , Schwamm Lee H , Daugherty Stacie L , Bradley Cathy , Burke James , Ho Michael
Published: February 2023

Background:
We examined the effect of CV and non-CV risk factors on the development of strokes in young adults 18-55 years old.

Methods:
This case-control study, using the Colorado All Payer Claims Database (APCD), identified young adults with index stroke admissions and assigned them(1:3) to controls matched on age/sex/insurance type(commercial or public)/enrollment duration. Controls were assigned a proxy stroke date based on their matched case. CV and non-CV risk factors occurring from enrollment until 1 day prior to stroke date were included. Pregnancy, postpartum, and oral contraceptives were separated from other non-CV risk factors in women. To assess whether there was a differential effect of the risk factors by age in each sex, conditional logistic regression models were fit separately for men and women with an interaction between age and risk factor.

Results:
Between 2012-2018, 2735 index stroke admissions were identified (52.3% women) and matched to 8,178 controls. In men with stroke, 53.4% and 27.7% had at least one CV and non-CV risk factor, respectively. In women with stroke, 57.6%, 41.0%, and 12.1% had at least one CV, non-CV and hormonal risk factor, respectively. The most common CV risk factors were hypertension(27.8%), hyperlipidemia(26.8%), tobacco use(20.9%) in men and hypertension(25.5%), tobacco use(22.9%), obesity(22.6%) in women. The most common non-CV risk factors were migraines (14.3%), renal failure(6.9%), thrombophilia(6.1%) in men and migraines(29.1%), malignancy(9.5%), thrombophilia(6.7%) in women. Having one or more CV or non-CV risk factors significantly contributed to the development of strokes(Figure). Controlling for CV risk factors, having at least one non-CV risk factor had the highest risk among men and women <45. Hormonal risk factors significantly contribute to strokes in women ≥35.

Conclusions:
Non-CV risk factors play a significant role in the development of strokes among young adults and warrants further study.
Abstract TP204: Elimination Of Senescent Cells Prevents The Development Of Intracranial Aneurysm Rupture In Mice
Authors: Take Yushiro , Sato Hiroki , Ai Jinglu , Lawton Michael , Hashimoto Tomoki N
Published: February 2023

Introduction:
Aging is one of the risk factors for intracranial aneurysm rupture. Aging causes various changes in cellular homeostasis, including cellular senescence. Cellular senescence is defined as a state of irreversible cellular growth arrest. Senescence cells secrete pro-inflammatory senescence-associated secretory phenotypes (SASPs). SASPs affect surrounding cells and contribute to a vicious cycle of senescence and induce inflammation. Recent studies strongly suggest that inflammation promotes aneurysm rupture. Therefore, the accumulation of senescence cells may induce aneurysm rupture due to pro-inflammatory effects of SASPs. We hypothesized that the elimination of senescence cells reduces the aneurysm rupture. To test our hypothesis we used p16-3MR mice. P16-3MR mouse is a transgenic mouse model, in which senescence cells can be eliminated by treatment of ganciclovir (GCV). In previous reports, the elimination of senescence cells by GCV in p16-3MR mice improved senescence-related diseases. In this study, we tested whether the elimination of senescence cells by GCV in p16-3MR mice reduces the intracranial aneurysm rupture rate.

Methods:
We induced intracranial aneurysms by combining systemic hypertension and a single injection of elastase into the cerebrospinal fluid in mice. We compared the vehicle to GCV group in p16-3MR aged male mice (10-15 months, vehicle vs GCV: 9 vs 6). We started GCV treatment the same day after aneurysm induction. Aneurysm rupture rate was used as the primary endpoint.

Results:
There was no statistical difference in the formation rate of aneurysms between the vehicle and the GCV group. However, the aneurysmal rupture rate was significantly lower in the senescence cell-depleted mice (P < 0.05). Additionally, the symptom-free curve (Kaplan-Meier analysis curve) showed a significant reduction of aneurysm rupture in the GCV-treated group (P < 0.05).

Conclusions:
The elimination of senescence cells reduced the aneurysm rupture rate in a mouse model of the aneurysm. Our results suggest that the accumulation of senescence cells induces aneurysm rupture. Therefore, the pharmacological prevention of the accumulation of senescence cells may be a new therapeutic target in aneurysm rupture.