bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P332: Cerebral Small Vessel Disease Score in CADASIL: Relationships to Cognitive Dysfunctions
Authors: Schoemaker Dorothee , Zuluaga Yesica , Velilla Lina , Ospina Carolina , Lopera Francisco , Arboleda-Velasquez Joseph , Quiroz Yakeel
Published: March 2021

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary cerebral small vessel disease (cSVD) linked to NOTCH3 mutations and leading to the early onset of stroke and vascular cognitive impairment. Neuroimaging features of CADASIL include extensive white matter hyperintensity, lacunes, cerebral microbleeds and enlarged perivascular spaces. Researchers from the Rotterdam study recently proposed a MRI-based cSVD Score reflecting the overall burden of cerebrovascular injury (Yilmaz et al., 2018). Here, we explored the relevance of this cSVD Score in distinguishing CADASIL subjects from non-carriers and its relationships to cognition.

We evaluated 26 NOTCH3 mutation carriers and 25 non-carriers from large Colombian families. Of the CADASIL subjects, 4 had previous strokes (symptomatic) and 22 had no history of strokes (asymptomatic). All subjects underwent a 3T MRI and a neuropsychological evaluation. Structural MRI markers of cSVD, as well as the cSVD Score, were quantified in each subject following established protocols.

Demographic, cognitive and neuroimaging features across groups are presented in Table 1. The cSVD Score significantly differed between groups, after adjusting for age (Figure 1-A). In CADASIL subjects, the cSVD Score was negatively related to performance in Memory, Processing Speed, Executive Function, after accounting for age and education (Figure 1-B).

These results suggest that the cSVD Score could be a useful marker of disease severity in CADASIL. Longitudinal studies are now needed to determine if this score allows predicting clinical outcomes in CADASIL, such as stroke or dementia.
Abstract P335: Post-Treatment Blood-Brain Barrier Disruption is Associated With Cerebral Edema and Extends Into Penumbral Tissue in Anterior Circulation Large Vessel Occlusion
Authors: Ng Felix , Sharma Gagan , Churilov Leonid , Yassi Nawaf , Kleinig Timothy , Davis Stephen , Mitchell Peter , Leigh Richard , Campbell Bruce
Published: March 2021

Background:
Blood Brain Barrier (BBB) disruption is central to vasogenic edema development after ischemia in preclinical studies. We investigated the relationship between BBB disruption and cerebral edema in patients receiving reperfusion therapies for anterior circulation large vessel occlusion.

Methods:
In a post-hoc pooled analysis of the Tenecteplase versus Alteplase before Endovascular Therapy for Ischemic Stroke (EXTEND-IA TNK) part 1 and 2 multicenter RCTs, the DWI lesion on 24h post-treatment MRI and peri-infarct salvaged penumbra derived from pre-treatment CT-Perfusion (CTP) were segmented and registered to 24h MR Perfusion. A validated permeability measure (percentage of measured cerebral blood volume lost due to T1 effect from gadolinium leakage across the BBB) was calculated for each ROI. The association between post-treatment BBB disruption in the infarct and cerebral edema assessed on a trichotomized ordinal scale of negligible (<1mm midline shift), mild (≥1 to <5mm) or severe (≥5mm) was analyzed using ordinal logistic regression.

Results:
Of 220 patients analyzed, median (IQR) BBB disruption was 2.36(1.4-4.1)% in the infarct, 1.61(1.0-2.6)% in salvaged penumbra and 0.98(0.7-1.5)% in normal brain (p<0.001). There were 119 (54.1%) patients with negligible, 90 (40.8%) mild and 11 (5.0%) severe cerebral edema at 24h. In multivariable analysis, infarct BBB disruption was associated with increased cerebral edema (cOR=1.11 per%, 95%CI 1.02-1.21;p=0.012, adjusted for age, admission NIHSS and reperfusion (mTICI2b/3 or >50% reperfusion on early CTP 2h post-lysis). Infarct BBB disruption correlated with follow-up infarct volume (rho=0.37;p<0.001), and was associated with parenchymal hematoma (aOR=1.18, 95%CI 1.00-1.40;p=0.048) and worse outcome assessed on 90-day modified Rankin Scale (cOR=1.16 per%, 95%CI 1.08-1.26;p<0.001, adjusted for age, admission NIHSS and reperfusion).

Conclusions:
BBB disruption after reperfusion treatment extends beyond the infarct lesion, and is associated with cerebral edema development, hemorrhagic transformation and poor outcome. Further studies to evaluate BBB integrity as an imaging biomarker and potential therapeutic target in malignant cerebral edema after ischemic stroke are needed.
Abstract P349: Neuroprotective Effects of L-Carnitine on Vascular Dementia in Hemodialysis Patients
Authors: Ueno Yuji , Urabe Takao , Hattori Nobutaka
Published: March 2021

Background and purpose:
L-carnitine alleviated oxidative stress and white matter lesions in an experimental study. Cognitive decline is not uncommon in hemodialysis patients, the pathogenesis of which has not been elucidated.

Methods:
Using novel diffusion magnetic resonance imaging techniques, white matter microstructural changes and cognitive decline in hemodialysis patients, and the effects of l-carnitine on such disorders were investigated. Fourteen hemodialysis patients underwent diffusion tensor imaging, diffusion kurtosis imaging, neurite orientation dispersion and density imaging, and laboratory and neuropsychological tests, which were compared between two groups based on the duration of l-carnitine treatment: (1) no or short-term l-carnitine treatment; and (2) long-term l-carnitine treatment. Ten age and sex-matched controls were enrolled.

Results:
On neuropsychological testing, the majority of hemodialysis patients were categorized as having mild cognitive impairment. Seven patients were classified into the no or short-term l-carnitine treatment and long-term l-carnitine treatment groups. Compared to controls, microstructural disorders of white matter were widely detected in no or short-term l-carnitine treatment on diffusion magnetic resonance imaging. An autopsy study from the no or short-term l-carnitine treatment group showed rarefaction of myelinated fibers in white matter. In long-term l-carnitine treatment, microstructural damage on diffusion magnetic resonance imaging was alleviated along with lower levels of high-sensitivity C-reactive protein (
P
<0.001) and substantial increases of carnitine levels (
P
<0.001). The long-term l-carnitine treatment group showed better achievement in Trail Making Test-A (
P
=0.017), which was correlated with amelioration of disorders in bilateral anterior thalamic radiations, the left cingulum in the cingulate gyrus, the right superior longitudinal fasciculus, and the forceps major (
P
<0.05).

Conclusion:
Novel diffusion magnetic resonance imaging tractography detected abnormalities of white matter tracts in hemodialysis patients. Long-term treatment with l-carnitine alleviated white matter microstructural damage and cognitive impairment.
Abstract P352: Reversible Relative FLAIR Signal Intensity Changes in the Penumbra Correlate With Severity of Hypoperfusion
Authors: Scheldeman Lauranne , Wouters Anke , Dupont Patrick , Christensen Soren , Boutitie Florent , Cheng Bastian , Ebinger Martin , Endres Matthias , Fiebach Jochen B , Gerloff Christian P , Muir Keith W , Nighoghossian Norbert , Pedraza Salvador , Simonsen Claus , Ringelstein Erich Bernd , Chamorro Angel , Grond Martin , Laage Rico , Thomalla Gotz , Thijs Vincent , Lemmens Robin
Published: March 2021

In ischemic stroke, the study of edema, measurable as fluid attenuated inversion recovery (FLAIR) signal increase, has mainly focused on the ischemic core and less on the surrounding penumbra. To the naked eye, no FLAIR changes are present in the penumbra. However, changes in perfusion status could induce physiological changes resulting in subtle penumbral FLAIR signal alterations. To investigate penumbral FLAIR changes, we included subjects from the Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke (WAKE-UP) and Granulocyte Colony-Stimulating Factor in Patients With Acute Ischemic Stroke (AXIS 2) trial with perfusion- and diffusion-weighted imaging (PWI, DWI) and FLAIR at baseline. We used RAPID software to calculate the core and perfusion lesion on DWI and PWI and selected subjects with a minimal mismatch volume (15 ml) and ratio (1.2). We created voxel-based relative FLAIR signal intensity (rFLAIR SI) maps at baseline and follow up (FU) by calculating the ratio of the FLAIR intensity in one voxel and the median FLAIR intensity in a sphere with 15 mm radius around a contralateral homologues voxel. We studied rFLAIR SI in two regions of interest: the baseline penumbra (baseline perfusion lesion - [core lesion + voxels with apparent diffusion coefficient <620 10
-6
mm
2
/s]) and the non-infarcted penumbra (baseline perfusion lesion - FU FLAIR lesion) at 24 hours (WAKE-UP) or 30 days (AXIS 2). Severity of hypoperfusion was defined as the time to maximum of the residue function. In the baseline penumbra, rFLAIR SI was elevated (ratio=1.04, p=1.7*10
-13
,
n=126) and correlated with severity of hypoperfusion (Pearson’s r 0.03, p<1.0*10
-4
, n=126). At 24 hours in a subgroup from WAKE-UP, rFLAIR SI in the non-infarcted penumbra further increased (ratio=1.05 at 24h vs 1.03 at baseline, p=7.1*10
-3
, n=43). In a different subgroup from AXIS 2, this increase in rFLAIR SI was reversible (ratio=1.02 at 30d vs 1.04 at baseline, p=1.5*10
-3
n=26) since it was no longer different from 1 at 30 days (ratio=1.01 at 30 days, p=0.099, n=26). Increases in rFLAIR SI, likely representing edema, are not restricted to the ischemic core and correlate with severity of hypoperfusion in the penumbra. They appear early after stroke onset, further increase at 24 hours and are reversible by 30 days.
Abstract P353: FLAIR-Positive Acute Ischemic Stroke and Less Favorable 90-Day Outcome After IV Thrombolysis
Authors: Kim Yongwoo , Luby Marie , Burkett Nina-serena F , Norato Gina , Leigh Richard , Wright Clinton B , Kern Kyle C , Hsia Amie W , Lynch John K , Adil Malik M , Latour Lawrence
Published: March 2021

Background and Purpose:
It is well established that earlier treatment times are associated with better outcomes in acute stroke patients receiving thrombolysis. There is also an association between time from stroke onset and lesion visibility on FLAIR MRI. We hypothesized that lesion visibility on FLAIR, independent of time, may be a predictor of outcome in stroke patients with known onset.

Methods:
We analyzed data from acute ischemic stroke patients presenting over the last 10 years who were screened with MRI and treated with IV thrombolysis within 4.5 hours from known onset. Three independent readers assessed whether acute ischemic lesions seen on Diffusion Weighted Imaging were also FLAIR-positive based on visual inspection. Multivariable regression analysis was used to obtain an adjusted odds ratio of favorable clinical and radiological outcomes based on FLAIR-positivity.

Results:
Of 310 stroke patients, 24% had lesion visibility on initial FLAIR MRI. The interrater agreement for the FLAIR-positive assessment was 84% (κ=0.604, 95% CI 0.557-0.652). Patients with FLAIR-positive lesions were younger (67 vs 73 years, p=0.028), had more right hemispheric strokes (57% vs 42%, p=0.018), were imaged later (127 vs 104 minutes, p=0.010), had more frequent blood-brain barrier disruption (44% vs 26%, p=0.004), less frequent early neurologic improvement (30% vs 58%, p<0.001), and less frequent favorable 90-day functional outcome (49% vs 63%, p=0.039). Following multivariable logistic regression, older age, greater NIH Stroke Scale, lesion visibility on FLAIR, but not time-from-onset, were independently associated with less favorable outcome.

Conclusions:
FLAIR-positive acute ischemic stroke within 4.5 hours of known onset was associated with less favorable 90-day outcome after IV thrombolysis. When compared with time, lesion visibility on FLAIR was more strongly associated with outcome.
Abstract P360: Clot Burden Score and Collateral Score: Emerging Predictors of Outcome
Authors: Gulati Deepak K , Yadav Randheer S , Lakhani Sushil , Hamed Mohammad , Peters Elizabeth , Nimjee Shahid M , Powers Ciaran , Youssef Patrick , Boulter Daniel
Published: March 2021

Introduction:
With the recent advancement, there are still large number of stroke patients who end up with poor outcome despite getting thrombectomy. Clot extent, location, and collateral integrity are found to be important determinants of outcome in acute stroke. The CBS is a scoring system (0-10) to define the extent of thrombus on CTA. The collateral grading system is scored on a scale of 0-3 on CTA. The purpose of this study is to compare the relationship of clot extent and collaterals with clinical and radiological outcome.

Hypothesis:
A novel clot burden score (CBS) and collateral score (CS) are important determinants of outcomes and serve as useful additional stroke outcome predictors.

Methods:
One hundred and twenty eight stroke patients with large vessel occlusion who underwent endovascular thrombectomy in our institution were reviewed retrospectively. CBS and CS were calculated on CTA by a neuroradiologist and a vascular neurologist and reached a consensus who were blinded about clinical information. Patients were dichotomized using collateral scores as good (>/=2) vs bad collaterals (0-1). Univariate and multivariate analysis is performed.

Results:
A total of 128 patients included in the study. Poor collateral is found to be associated with prior history of Afib (47% vs 32%) whereas smoking is found to be associated with good collaterals (38% vs 29%). Low CBS (higher clot burden) is associated more with poor collaterals (70% vs 46%). Poor collateral is associated with higher inhouse mortality (23% vs 9%) and increase number of patients with mRS of 5-6 at 3 months (42% vs 21%). Revascularization rate TICI 2b-3 is not found to be significantly associated with the degree of collaterals (93% with good collaterals whereas 78% in poor collaterals)

Conclusions:
CBS and CS are useful additional markers predicting clinical and radiologic outcomes and could be potentially used clinically as an adjunct to other imaging and clinical features to stratify patient risk better.
Abstract P363: Predictors of Utility of Advanced Cardiac Imaging in Revealing Cryptogenic Stroke Etiology
Authors: Schachter Daniel M , Schachter Micaela , Beehler Blake , Quinn Jeffrey , Kulacz Jeremy E , Vargas Alejandro , Osteraas Nicholas D , Cherian Laurel J , Song Sarah , Conners James , da silva ivan , Dafer Rima M
Published: March 2021

Introduction:
Advanced cardiac imaging (ACI), including transesophageal echocardiogram (TEE), cardiac CT and cardiac MRI, is widely considered a crucial element in the work-up of cryptogenic and ESUS stroke. Current data on diagnostic yields are variable, though, and selection of patients to undergo such imaging is largely anecdotal.

Methodology:
We conducted a retrospective case series review of all cryptogenic ischemic strokes who received ACI, admitted to a large urban academic single-center over a 2.5-year period. Patient characteristics and imaging findings were analyzed to determine diagnostic yields and to identify positive and negative predictors that ACI would uncover etiology.

Results:
Out of 277 total cryptogenic ischemic strokes reviewed, ACI determined etiology in 20 cases (7.2%). Median age was 61 (IQR = 52-73). Patient sex was 49.5% female. Race demographic was 1.8% Asian, 50.9% black, 14.1% latino(a), and 33.2% white. Etiology was found by TEE in 16 of 20 cases, and the most common finding was left atrial thrombus/smoke. Latino(a) race was significantly more likely (15.4%) for ACI to find etiology and white race was significantly less likely (1.1%), p = .03 and .005, respectively. The table included shows other notable findings. Analogous trends were observed in a subgroup analysis of patients greater or equal to 60 years old.

Conclusion:
Our data indicate that in cryptogenic stroke premorbid non-use of antithrombotic, elevated troponin and left atrial dilatation are each individually associated with increased likelihood that ACI will find an etiology. Meanwhile, patients with diabetes mellitus are significantly less likely to have etiology found by ACI; and, smokers with combined hypertension, hyperlipidemia, and diabetes mellitus trend towards ACI less frequently uncovering etiology. Finally, the data suggest potential racial disparities of finding etiology with ACI, the determinants of which remain to be studied.
Abstract P364: Use of the Electronic Alberta Stroke Program Early CT Score Software to Guide Treatment of Patients With Acute Ischemic Stroke
Authors: Weiss Danielle L , Chuang Dennis Y , Fadhil Ali , Duncan Kelsey R , Weiss Alexa , Smith Mickey L , Sundararajan Sophia
Published: March 2021

Introduction:
Rapid recognition of large-vessel middle cerebral artery (lvMCA) stroke in patients with acute stroke symptoms is critical to guide thrombectomy and hemicraniectomy decisions. The Electronic Alberta Stroke Program Early CT Score (e-ASPECTS; Brainomix, LLC) is an automated, artificial intelligence software which quantifies acute ischemic volume (AIV) on CT head scans in the MCA territory. In this study, we investigate if e-ASPECTS-derived AIV could help guide treatment and predict outcomes for patients transferred from community hospitals.

Hypothesis:
E-ASPECTS can help identify patients that may benefit from thrombectomy or hemicraniectomy.

Methods:
We performed a retrospective chart review on patients age 18-90 transferred to our comprehensive stroke center (CSC) between 2013-2017. Non-contrast CT head scans performed at community hospitals prior to transfer were processed by e-ASPECTS to calculate AIV. Logistic regressions were used to test the relationship between AIV and eventual treatment (thrombectomy, hemicraniectomy).

Results:
228 patient CT scans were analyzed by e-ASPECTS. In all transferred patients, higher AIV predicted patients with later confirmed lvMCA strokes (defined as an ICA or M1 occlusion; OR 1.03, CI 1.02-1.05, P<0.001). Higher AIV also trended toward thrombectomy but was not statistically significant (P=0.15). In the subgroup analysis of patients later confirmed to have lvMCA strokes, lower AIV was predictive for thrombectomy (OR 0.95, CI 0.92-0.97, P<0.001). Additionally, higher AIV predicted outcomes of malignant cerebral edema (MCE; OR 1.03, CI 1.02-1.05, P<0.001) and hemicraniectomy (OR 1.04, CI 1.00-1.07, P=0.03).

Conclusions:
Our study suggests that e-ASPECTS may be useful in identifying patients who would, or would not, benefit from transfer to a CSC from hospitals without thrombectomy or hemicraniectomy resources. Patients with stroke mimics or lvMCA strokes with large penumbras have lower AIVs, while patients with higher AIVs are at risk for MCE and may benefit from hemicraniectomy.
Abstract P365: Effect of Radiological Thrombus Characteristics on Results of First-Line Endovascular Treatment Approach for Acute Ischemic Stroke
Authors: Kappelhof Manon , Bruggeman Agnetha , Brouwer Josje , Arrarte Terreros Nerea , Konduri Praneeta R , Markenstein Jeroen E , van den Berg René , Sprengers Marieke E , van Zwam Wim H , van der Leij Christiaan , van den Wijngaard Ido , Dippel Diederik W , Majoie Charles B , Marquering Henk
Published: March 2021

Introduction:
Pervious thrombi benefit more from intravenous thrombolysis, but the role of perviousness in endovascular treatment (EVT) is not completely clear. Thrombus length is negatively associated with outcome after EVT. Pervious, long thrombi may be more difficult to aspirate, or fragment more easily than non-pervious, short thrombi. We assessed the effect of perviousness and thrombus length on results of first-line aspiration thrombectomy in EVT, in comparison to stent-retrievers.

Methods:
We included MR CLEAN Registry patients (N=1526) with thin-slice imaging available, and aspiration or stent-retriever as first EVT attempt (N=391). Thrombus perviousness was measured by thrombus attenuation increase (Houndsfield Units; HU). Associations with 90-day modified Rankin Scale score (mRS), and final and first-pass reperfusion (eTICI 2B-3) were tested with adjusted logistic regression analyses.

Results:
Sixty-five (21%) patients were treated with first-line aspiration, 252 (79%) with stent-retrievers. Perviousness was not significantly associated with mRS after either first-line approach (Figure 1). Analysis per perviousness quartile did show improved mRS for stent-retrievers in the highest quartile only (>12.3 HU; acOR for mRS shift with stent-retriever treatment 3.08, 95%CI 1.06-8.96). Thrombus length was negatively associated with mRS after first-line stent-retriever thrombectomy (acOR 0.96, 95%CI 0.93-0.99). First-pass reperfusion and thrombus length were significantly, negatively associated in the first-line aspiration group (acOR 0.88, 95%CI 0.80-0.96).

Conclusions:
Patients with longer thrombi may show worse outcomes after both aspiration and stent-retriever thrombectomy. In patients with high perviousness values, stent-retriever thrombectomy may be related to improved outcomes as compared to first-line aspiration.
Abstract P378: Automated Estimation of Ischemic Core Volume on Non-Contrast-Enhanced Computed Tomography via Machine Learning
Authors: CHEN IRIS E , Tsui Brian , Qiao Joe X , Hsu William , Sharma Latisha K , Hosseini Mercedeh B , Nour May , Hinman Jason D , Kim Doojin A , Rao Neal M , Salamon Noriko , Saver Jeffrey L , Liebeskind David S , Nael Kambiz
Published: March 2021

Background and Purpose:
Accurate estimation of ischemic core on baseline imaging has treatment implications in patients with acute ischemic stroke (AIS). Machine learning (ML) algorithms have shown promising results in estimating ischemic core using routine non-contrast CT (NCCT). We used a ML-trained algorithm to quantify ischemic core volume on NCCT and compared the results to concurrent diffusion MRI as the reference standard in patients with AIS.

Methods:
We analyzed consecutive anterior circulation AIS patients who had baseline (pretreatment) NCCT and MRI (DWI). Ischemic lesion volume was calculated on MRI-DWI using an automated software (Olea Medical SAS, La Ciotat, France). An automatic segmentation approach using a combination of traditional 3D graphics and statistical methods, and ML classification techniques (Brainomix, Oxford, United Kingdom) was used to identify ischemic core voxels on NCCT. Total ischemic core volumes on ML-NCCT and DWI-MR were quantitatively compared by Bland-Altman plots and Pearson correlation.

Results:
A total of 50 patients (27 female, 23 male, mean age 72.6 years) were included. Baseline imaging was performed within 173 ± 143 minutes (mean ± SD) from symptom onset. The mean time difference between MRI and NCCT was 72 min. The baseline NIHSS was 14, 8-21 (Median, IQR). Algorithm-segmented ischemic core volume detected on NCCT was median 12.7 mL, IQR 3.5-26.0 mL. Ischemic core volume on DWI MRI was median 8.8 mL, IQR 3.2-34.0 mL. ML-NCCT core volumes significantly correlated with DWI MRI core volumes,
r
=0.61,
p
<0.001. The mean difference between the ML-NCCT and DWI MRI core volumes was 12.4 mL,
p
=0.81. For the reperfusion treatment threshold of an ischemic core volume within 70 mL, while no patients would have been excluded using our algorithm, five patients would have been incorrectly dichotomized as having an ischemic volume of <70 mL compared to MRI.

Conclusion:
This ML-approach accurately quantifies ischemic core volume on NCCT compared to the reference standard of diffusion MRI in patients with AIS.
Abstract P389: External Validation of the 2CAN Score for Inpatient Stroke Detection
Authors: otlivanchik oleg , Lu Jenny , Cheng Natalie , Labovitz Daniel L , esenwa charles , Milstein Mark , Antoniello Daniel , Singh puneet , Liberman Ava L
Published: March 2021

Introduction:
Up to 15% of all strokes occur in patients who are already hospitalized for other conditions. A validated clinical tool to help rapidly discriminate between mimics and stroke among inpatients could greatly improve acute stroke care. Recently, the 2CAN score was developed and validated at a single Midwest academic medical center to identify inpatient strokes; a score of ≥2 was highly sensitive and specific for stroke. We sought to externally validate the 2CAN score at our institution.

Methods:
We conducted a retrospective cohort study of consecutive inpatient stroke codes at a single Northeast academic medical center from 7/1/2018 to 11/1/2019. Pre-specified variables, including patient demographics, vascular risk factors, and clinical features (neurological examination, vital signs, laboratory values, and final diagnoses), were abstracted from the electronic medical record. We determined the sensitivity, specificity, positive and negative predictive value of a 2CAN score ≥2 for stroke (ischemic stroke, hemorrhagic stroke, or TIA) in our cohort. The 2CAN score consists of clinical deficit score (0-3 points), recent cardiac procedure (1 point), atrial fibrillation (1 point), and code called within 24 hours of admission (1 point). We used multivariate logistic regression to identify additional determinants of stroke.

Results:
We identified 111 inpatient stroke codes on 110 patients, mean age 67 ± 1 year, 46.8% women, and 73.8% Black or Hispanic. Final diagnosis was stroke for 54 codes (48.6%) and mimic for 57 codes (51.3%), most commonly toxic-metabolic encephalopathy. 2CAN score ≥2 had 96.3% sensitivity, 45.6% specificity, 62.7% positive predictive value, and 92.3% negative predictive value for stroke. In a multivariable logistic regression model, only recent cardiac procedure (OR: 5.5; 95% CI: 1.1-27.5) and high clinical deficit score (OR: 3.9; 95% CI: 1.9-6.1) predicted stroke.

Conclusion:
The 2CAN score is externally valid and helps distinguish stroke from mimic in inpatients; having a score of <2 makes stroke very unlikely.
Abstract P391: An-adcs
2
: A Novel Machine-Learning Model to Predict the Risk of Stroke-Associated Pneumonia
Authors: Ding Lingling , Li Zixiao , Wang Yongjun
Published: March 2021

Objective:
We aimed to develop and validate a machine learning-based prediction model that could assess the risk of stroke-associated pneumonia (SAP) for individual patients with acute ischemic stroke (AIS).

Methods:
A machine-learning model incorporating A
2
DS
2
scores and clinical features (AN-ADCS
2
) was developed to predict the risk of SAP in patients with AIS. Two independent datasets were used for model derivation and external validation. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were estimated. The further analysis evaluated thresholds from the training set that identified patients as low-risk, intermediate-risk and high-risk, and performance at these thresholds was compared in the external validation set.

Results:
The AN-ADCS
2
model achieved favorable performance with a high AUC of 0.892 (95% confidence interval [CI] 0.885-0.898) in the test set and similar performance in the external validation set (AUC 0.813 [95% CI 0.812-0.814]). The AN-ADCS
2
threshold identifying low-risk was 0.03, with a NPV of 97.6% (97.2-97.9%) and sensitivity of 93.5% (92.5-94.5%). The AN-ADCS
2
threshold identifying high-risk was 0.65, with a PPV of 94.7% (93.9-95.6%) and specificity of 99.5% (99.5-99.6%). The AN-ADCS
2
model performed better than the A
2
DS
2
score (AUC 0.739, 95%CI [0.720-0.754]). Having a high risk of SAP classified by the AN-ADCS
2
was associated with unfavorable outcomes of mortality and in-hospital stroke recurrence.

Conclusions:
Using machine learning, the AN-ADCS
2
model provides an individualized risk prediction of SAP, which can be used as an indicator of clinical prognosis for patients with AIS.
Abstract P393: Risk Factors for Opioid Use in Patients With Intracerebral Hemorrhage
Authors: Lin Nelson F , Mahta Ali , Chuck Carlin C , Kalagara Roshini , Doelfel Savannah R , Zhou Helen , Mahmoud Leana N , Stretz Christoph , Wendell Linda C , Thompson Bradford B , Furie Karen L , Reznik Michael E
Published: March 2021

Background:
Opioids are often used as analgesics in patients with subarachnoid hemorrhage, but their use in the setting of intracerebral hemorrhage (ICH) is not well described. We aimed to determine risk factors for opioid use in both the acute and post-discharge settings in patients with ICH.

Methods:
We analyzed data from a single-center cohort of consecutive ICH patients admitted over two years. Demographics and ICH-related characteristics were prospectively collected as part of an institutional ICH registry, while pre-morbid, in-hospital, and post-discharge medications were retrospectively abstracted from medication administration records and physician documentation. After excluding patients who received end-of-life care, we used multivariable regression models adjusted for pre-morbid opioid use to determine demographic and ICH-related risk factors for in-hospital and post-discharge opioid use.

Results:
Of 468 patients in our cohort, 15% (n=70) had pre-morbid opioid use, 53% (n=248) had in-hospital opioid use, and 12% (n=53) of survivors had opioids prescribed at discharge. The most commonly used in-hospital opioids were fentanyl (38% of patients), oxycodone (30%), morphine (26%), and hydromorphone (7%). Patients who received in-hospital opioids were significantly younger (mean 62.7 vs. 74.0 years, p<0.001) and had larger ICH volumes (mean 18.7 vs. 8.1 cc, p<0.001), with additional risk factors including infratentorial location (OR 4.0, 95% CI 2.0-8.0), presence of intraventricular hemorrhage (OR 4.3, 95% CI 2.5-7.5), and vascular, neoplastic, or other secondary ICH etiologies (OR 2.6, 95% CI 1.4-4.7) in multivariable models. However, only secondary ICH etiologies (OR 4.1, 95% CI 1.8-9.1) remained significant risk factors for opioid prescriptions at discharge in ICH survivors.

Conclusion:
Inpatient opioid use in ICH patients is common, with risk factors that may be mechanistically connected to headache pathophysiology. However, the lower frequency of post-discharge opioid prescriptions may be reassuring given the prevalence of opioid dependence nationwide.
Abstract P400: Racial Disparities in Subarachnoid Hemorrhage Outcomes-A Single Center Experience
Authors: Deas Jerome , Almallouhi Eyad , Banerjee Chirantan
Published: March 2021

Introduction:
Subarachnoid hemorrhage (SAH) has high morbidity and mortality, and prior studies have reported outcome disparities between African American (AA) and Caucasian patients. We compared demographics, risk factors, and discharge outcomes among different ethnicities treated at our comprehensive stroke center.

Methods:
We used data on all SAH patients admitted between July 2014 and March 2020 to our university hospital in the Southeast United States. Race was categorized into AA, Caucasian, and “other.” Pearson chi-square test and analysis of variance were used to compare these variables between the different groups.

Results:
A total of 578 SAH patients were identified (39% AA patients, 54% Caucasian, and 7% other). Admission Glascow Coma Score (GCS) and Hunt & Hess scores were comparable between the 3 groups. AA patients were significantly younger (51 vs 59 in Caucasian group vs 56 years in Other, p-value <0.001) and had higher BP at admission (systolic BP 152 vs 144 vs 145, p=0.002, diastolic BP 86 vs 80 vs 81, p<0.001). AA patients were more likely to have a history of hypertension (p<0.001) and had higher BMI (30 vs 28.1 vs 26, p=0.003) and Hemoglobin A1c (5.8 vs 5.6 vs 6.1, p=0.013). Modified Rankin scale (mRS) at discharge, in-hospital mortality, and discharge destination were similar between the groups, but AA patients had a longer mean hospital length of stay (19 vs 14 vs 17 days, p=0.035).

Conclusion:
In our cohort, AA SAH patients were significantly younger and had more comorbidities at admission. Although they had a higher length of stay, discharge outcomes were comparable to other races.
Abstract P407: Etiology And Outcomes Of Non-traumatic Intracerebral Hemorrhage - Data From The Swiss Stroke Registry
Authors: Goeldlin Martina , Mueller Achim , Siepen Bernhard , Mueller Madlaine , Strambo Davide , Cereda Carlo W , Berger Christian , Medlin Friedrich , Peters Nils , Renaud Susanne , Niederhaeuser Julien , Carrera Emmanuel , Bonvin Christophe , Sturzenegger Rolf , Kahles Timo , Nedeltchev Krassen , Kaegi Georg , Rodic Biljana , Bolognese Manuel , Schelosky Ludwig , Salmen Stephan , Mono Marie-Luise , Bonati Leo H , Polymeris Alexandros , Engelter Stefan , Lyrer Philippe , Wegener Susanne , Z’Graggen Werner , Bervini David , Volbers Bastian , Dobrocky Tomas , Fandino Javier , Arnold Marcel , Fischer Urs M , Seiffge David
Published: March 2021

Background:
We determined the frequency of different etiologies of non-traumatic intracerebral hemorrhage (ICH) and their association with clinical characteristics and outcomes.

Methods:
We analyzed data from consecutive ICH patients enrolled in the prospective Swiss Stroke Registry (2014-2019). Etiology of ICH was determined according to prespecified, mutually exclusive categories. We assessed prevalence of ICH etiologies, their association with clinical characteristics, functional independence (modified Rankin Scale 0-2), mortality, recurrent ICH and ischemic stroke at 3 months.

Results:
We included 2584 patients (median age 72y, IQR 64-82, 46.6% female, median NIHSS 10; IQR 3-15). 2037 patients (80%) had hypertension and 553 (22.3%) were on anticoagulants. Distribution of etiologies was as follows: Hypertension (n=1216 patients; 47.1% of all / 56.3% of patients with hypertension), unknown etiology (n=542, 21.0%), antithrombotic therapy (n=225, 8.7% of all / 38% of patients on anticoagulants), cerebral amyloid angiopathy (CAA, n=211, 8.2%), macro-vascular (n=121, 4.7%), other determined etiologies (n=269, 10.4%). Patients with hypertensive ICH had significantly higher NIHSS (median 9; IQR 4-16) and blood pressure levels (median systolic 176; IQR 156-195) on admission. Patients with CAA had significantly lower NIHSS at baseline (median 5; IQR 2-12). Three month follow-up was available for 2109/2584 patients (81.6%). 820 (38.9%) were functionally independent, 658 have died (31.2%). Hypertensive ICH was associated with an increased rate of functional independence (aOR =1.42, 95%CI 1.06-1.90, p=0.02). 5.2% of patients had a cerebrovascular event within 3 months. CAA was associated with a high risk of recurrent ICH (HR 6.95, 95%CI 3.05-15.84, p<0.001). The risk of ischemic stroke (2.2%) was higher than that of ICH (1.5%) in patients with hypertensive ICH.

Conclusions:
In Swiss Stroke Units and Centers, one of two patients has ICH from a different cause than hypertension. The rate of functionally independent patients at 3 months seems higher than mortality. Absolute and relative risks of recurrent ICH and ischemic stroke after recent ICH differ among underlying etiologies.
Abstract P409: Cerebellar Atrophy and Its Clinical Implications in Cerebral Amyloid Angiopathy
Authors: Horn Mitchell J , Gokcal Elif , Becker J. A , Das Alvin S , Schwab Kristin , Rosand Jonathan , Polimeni Jonathan , Viswanathan Anand , Greenberg Steven M , Gurol M. E
Published: March 2021

Background:
Recent data show that cerebral amyloid angiopathy (CAA) might cause hemorrhagic lesions in cerebellar cortex as well as cerebral atrophy. However, the potential effect of CAA on cerebellar tissue loss and its clinical implications have not been investigated.

Methods:
We compared cerebellar volumes in 70 nondemented patients with probable CAA to 70 age-matched healthy controls (HC) and 70 age-matched Alzheimer’s disease (AD) patients. Volumetric analyses including cerebellar cortical volume (pCbll-CV), cerebellar subcortical volume (pCbll-ScV), cerebral white matter volume (pWMV), and cerebral white matter hyperintensity volume (pWMH) were calculated as percent of total intracranial volume. Gait velocity (meters/seconds) was used to investigate the potential effect of cerebellar tissue loss on gait function.

Results:
Patients with CAA had significantly lower pCbll-ScV and pCbll-CV compared to HC (1.49%±0.17 vs 1.71%±0.23, p<0.001 and 6.03%±0.50 vs 6.23%±0.56, p<0.027 respectively). When compared to AD, pCbll-ScV but not pCbll-CV was significantly lower in CAA (1.49%±0.17 vs 1.670.24, p<0.001). Diagnosis of CAA was independently associated with lower pCbll-ScV in a general linear model adjusting for age, sex and presence of hypertension when compared to both HCs and patients with AD (p<0.0001 for all associations, after Bonferroni correction for multiple comparisons). Lower pCbll-ScV was associated with lower gait velocity score in univariate and multivariate analysis adjusted for relevant variables (adjusted β=0.826, 95%CI 0.357-1.295, p=0.001).

Conclusion:
Patients with CAA show cerebellar atrophy; predominantly in the subcortical cerebellum when compared to both HC and AD patients. Cerebellar tissue loss independently correlated with worse gait function in CAA patients. Overall, this study supports the view that CAA causes cerebellar injury which might mediate gait disturbance in patients with CAA.
Abstract P410: Association of Serum GFAP With Hematoma Expansion and Poor Outcome After Intracerebral Hemorrhage: The Factor VII for ICH Trial
Authors: Leasure Audrey C , Vanent Kevin N , Bevers Matthew , Kimberly William T , Mayer Stephan A , Steiner Thorsten , Matouk Charles , Sansing Lauren H , Falcone Guido J , Sheth Kevin N
Published: March 2021

Background:
Biomarkers may help identify patients most likely to benefit from therapies. We tested whether serum glial fibrillary acidic protein (GFAP), a biomarker elevated early after intracerebral hemorrhage (ICH) in response to blood-brain barrier disruption, is associated with hematoma expansion (HE) and outcome after ICH and whether GFAP levels modify the effect of factor VII treatment.

Methods:
We performed an exploratory analysis of the recombinant activated factor VII for acute ICH (FAST) trial. FAST collected serum GFAP levels were collected at admission within 4 hours of ICH onset prior to factor VII treatment. We used regression analyses to evaluate the associations between serum GFAP, HE (dichotomized as >e; 33% or > 6 mL increase in ICH volume from baseline to 24h and as the absolute volume of expansion), and 3-month poor outcome (modified Rankin Scale score 4-6). We tested for interaction between GFAP and factor VII treatment by adding product terms to multivariable regression models.

Results:
Of 841 enrolled patients, we included 567 (67%) with available GFAP levels (mean age 64 [SD 13], female sex 203 [37%]). GFAP was associated with HE (adjusted odds ratio [OR] 1.54, 95% CI 1.10-2.17) and poor outcome (adjusted OR 1.86, 95% CI 1.18-3.09). Compared to patients in the lowest GFAP quartile, those in the highest quartile had 2 times the odds of HE (95% CI 1.08-3.89) and 2.7 times the odds of a poor outcome (95% CI 1.33-5.70). GFAP modified the association between factor VII treatment and HE volume (multivariable interaction p=0.04): treatment was not associated with reduced HE volume in the lowest GFAP quartile (β -0.44, 95% CI -3.54 to 2.67), but was associated with reduced HE volume in higher quartiles (β -3.82, 95% CI -7.58 to -0.06).

Conclusions:
In the FAST trial population, early GFAP levels were associated with HE and poor functional outcome. Factor VII treatment was associated with a greater reduction in HE volume in patients with higher GFAP levels. Serum GFAP may be useful for risk-stratifying patients early after ICH onset.
Abstract P426: Platelet Glycoprotein IIb/IIIa Inhibitors as an Adjunct to Stent Placement of Carotid Stenosis in Symptomatic Patients
Authors: Bhagavan Sachin M , Ishfaq Ammad , Ishfaq Muhammad F , Kumar Mukaish , Pulimamidi Shruthi , French Brandi R , Siddiq Farhan , Gomez Camilo r , Qureshi Adnan I
Published: March 2021

Background:
Intra-arterial or intravenous platelet glycoprotein (GP) IIb/IIIa inhibitors have been used as adjunct to stent placement of carotid stenosis in patients with ischemic stroke or transient ischemic attack.

Objective:
To determine the proportion of patients with ischemic stroke or transient ischemic attack who received platelet GP IIb/IIIa inhibitors as adjunct to carotid stent placement and associated outcomes.

Methods:
We analyzed data from Cerner Health Facts® which collected data from participating facilities from January 1, 2000 to July 1, 2018. We identified patients with ischemic stroke or transient ischemic attack who underwent carotid stent placement for carotid stenosis and received Abciximab, Eptifibatide, or Tirofiban. Outcome was defined by discharge destination and classified into none to minimal disability, moderate to severe disability, or death.

Results:
A total of 8.4 % of 4567 patients with ischemic stroke or transient ischemic attack who underwent carotid stent placement for carotid stenosis received platelet GP IIb/IIIa inhibitors. Patients who received platelet GP IIb/IIIa inhibitors were more likely to experience cerebral ischemia (14.8% versus 7.5%) and undergo intubation/mechanical ventilation (4.4% versus 2%). There was a significant difference between patients who did or did not receive platelet GP IIb/IIIa inhibitors in terms of in hospital mortality rates (2.7% versus 1.2%, p=0.0152), none to mild disability (67.3% vs 75.7%, p=0.0003), and moderate to severe disability (30.1% vs 23.1%,p=0.0024).

Conclusions:
Adjunct use of platelet GP IIb/IIIa inhibitors in patients undergoing carotid stent placement for symptomatic carotid stenosis was associated with increased rates of in hospital mortality and moderate to severe disability.
Abstract P427: Use of Machine Learning to Determine Predictors of Intracerebral Hemorrhage Expansion
Authors: Azher Aidan I , Coronado Ivan , Savitz Sean I , Aronowski Jaroslaw A , Salazar-Marioni Sergio , Abdelkhaleq Rania , Abdulrazzak Mohammad Ammar , Greco Jonathan , Sheth Sunil , Giancardo Luca
Published: March 2021

Background:
Intracerebral hemorrhage (ICH) constitutes upto 40% mortality in first 30 days. Early identification of predictors of hematoma expansion (HE) may improve efforts to prevent its occurrence and improve clinical outcome.

Methods:
We identified patients with ICH and follow-up imaging. HE was defined as a combination of absolute volume increase of 6cc, new IVH, or proportional increase of 33% in our dataset on 72h follow up scan. Presence of IVH was also included in hematoma expansion. We evaluated the predictive ability of 3 machine learning classifiers, Random Forest, Support Vector Machine (with RBF kernel) and Logistic regression (with L1 regularization). The evaluation was done using a K-fold stratified cross validation to avoid overfitting. K was selected to be the number of subjects with HE. The features employed by classifiers were entirely based on the baseline imaging: Hematoma volume, Systolic BP, Diastolic BP, Black hole signs, Island signs, Blend signs, Fluid level, Swirl signs, Spot signs.

Results:
Our dataset comprised of 91 patients (n=21 HE, n=70 no HE). According to the area under the ROC (AUC), the two top performing classifiers were Support Vector Machine (AUC=0.66 CI 0.50-0.79) and Logistic Regression (AUC=0.64 CI 0.49-0.80). The statistical significance of the prediction is confirmed by the Mann-Whitney U test, p=0.01 and p=0.04 respectively. Random Forest did not reach statistical significance. Finally, we evaluated what were the highest and lowest weighted features across the cross-validation with Logistic Regression. The 3 top features were: presence of black hole and island signs and the systolic blood pressure. The 3 least useful features were: presence of spot and swirl signs and hematoma volume.

Conclusion:
Using our cohort, we developed a machine learning algorithm that predicts hematoma expansion using imaging features and blood pressure. MBL provided better sensitivity of these imaging markers compared with previous studies.
Abstract P433: Multipotent Adult Progenitor Cells as a Highly Promising Therapy for Treatment of Intracerebral Hemorrhage
Authors: Zhao Xiurong , Obertas Lidiya , Sun Guanghua , Ting Shun Ming , Goh Andrew , Savitz Sean , Busch Sarah , Bogaerts Annelies , Mays Robert W , Aronowski Jaroslaw A
Published: March 2021

Background:
Multipotent adult progenitor cells (MAPC) are an adherent adult stem cell being evaluated as a treatment for ischemic stroke in humans under the name MultiStem®. However, the efficacy of MAPC cells for the treatment of intracerebral hemorrhage (ICH), the most devastating form of stroke for which there is no effective treatment, is not clear

Method:
The therapeutic efficacy of MAPC administration was evaluated in both autologous blood injection (ABI) and collagenase (COL) rat ICH models. We treated rats intravenously with 1.2x10
6
cells (sub-optimal dose based on MAPC efficacy in ischemic stroke) and 1.2x10
7
cells (optimal dose) at either 2 or 24h after ICH, and used 2 different doses of collagenase to better understand the dose responses. Outcome measurements included 4 sensorimotor tests (up to 28d), ventricular hypertrophy, spleen size, and body weight (N=128 rats tested across 4 separate experiments).

Results:
MAPC offered a robust benefit in both ICH models in a dose-dependent fashion. (1) ABI model: at the sub-optimal dose MAPCs had no significant effect on behavioral performance, but effectively reduced ventricular hypertrophy. At an optimal dose, MAPCs at 2h or 24h after ICH, robustly reduced deficits in all 4 behavioral tests, and reduced ventricular hypertrophy by 59% and 35% in 2h and 24h post-treatment groups, respectively. No difference in body weight and spleen size was observed. (2) COL model: MAPC administered 2h after high collagenase dose, reduced hematoma volume (hemispheric hemoglobin level), as measured at 48h after collagenase injection. In addition, MAPC administration significantly reduced neurological deficit in the COL model.

Conclusions:
MAPC provide a uniquely robust therapeutic effect on clinically relevant neurological and morphological outcomes in two different ICH models. MAPC also reduced bleeding in the COL model, suggesting the potential for MAPC as a safe acute therapeutic treatment after ICH. In addition to having beneficial effects on recovery processes, MAPC could be further evaluated as a candidate to limit the hematoma enlargement during the initial postictal period. We are currently investigating the mechanism of MAPC-induced post-ICH recovery as well as hemostasis using tissue microarray analysis.