bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP11: Semi-automated Quantitative Assessment of Reperfusion in Acute Ischemic Stroke Patients
Authors: Prasetya Haryadi , Ramos Lucas A , Epema Thabiso , Treurniet Kilian M , Emmer Bart J , van den Wijngaard Ido R , Zhang Guang , Berkhemer Olvert A , Yoo Albert J , Roos Yvo B , van Oostenbrugge Robert J , Dippel Diederik W , van Zwam Wim H , van der Lugt Aad , Majoie Charles B , van Bavel Ed T , Marquering Henk A ,   MR CLEAN Registry Investigators
Published: January 2019

Introduction:
Accurate assessment of brain reperfusion during endovascular treatment helps determining whether adjuvant intervention is necessary. The gold standard for reperfusion scales are the modified and extended Treatment in Cerebral Ischemia (mTICI and eTICI) scale. However, these scales are coarse and highly dependent on the observer, which may result in imprecise rating of reperfusion status. In this study, we developed a semi-automated quantitative reperfusion measure (qTICI) that was based on eTICI methodology using deep learning.

Methods:
Digital subtraction angiography (DSA) images of 67 acute ischemic stroke patients with proximal occlusions were collected from the MRCLEAN registry, including only patients who were eTICI graded by an independent core lab and had follow-up 90 days-modified Rankin Scale (mRS) scores. Both DSA projections, anteroposterior and lateral, were used. We trained a patch-based multi-path convolutional neural network to segment the perfusion area. The ground truths of perfusion segmentation were constructed using heuristic, intensity thresholding after vessel removal, which were inspected for their accuracy by a neuroradiologist. The target downstream territory was manually segmented based on the treated occlusion location by two neurointerventionalists. qTICI was formulated as a ratio between the area of perfusion and target downstream territory. We compared performance between qTICI and eTICI in relation with functional outcome, dichotomized as favorable (mRS 0-2) and unfavorable outcome (mRS 3-6).

Results:
Our study showed that the multi-path convolutional neural network was able to reproduce the ground truth perfusion segmentation with an average Dice score of 0.91. qTICI correlated significantly with eTICI (p<0.001) and the ordinal 90-days mRS (p<0.05). qTICI had comparable discriminative power to distinguish between favorable and unfavorable functional outcome (AUC = 0.80) with eTICI (AUC = 0.81).

Conclusions:
qTICI provided a quantitative and semi-automated perfusion assessment with strong association with functional outcome.
Abstract WP119: Stent-Assisted Coiling of Intracranial Aneurysms With the Neuroform ATLAS Stent: Immediate and Midterm Angiographic and Clinical Follow-Up
Authors: Ciccio' Gabriele , Robert Thomas , Smajda Stanislas , Fahed Robert , Blanc Raphael , Piotin Michel
Published: January 2019

Object:
Self-expandable stents have broadened the spectrum of endovascular treatment of intracranial aneurysms. The Neuroform ATLAS, the evolution of Neuroform EZ, is a nitinol self-expanding hybrid/open-cell stent, which can be delivered through a low-profile 0.017 inch catheter. We present our experience in the treatment of intracranial aneurysms with this stent.

Methods:
We prospectively maintained a database from consecutive patients who underwent stent-assisted coiling with Neuroform ATLAS from July 2015 to July 2018. Clinical and angiographic results were analyzed.

Results:
Ninety-one patients harboring 95 aneurysms were treated in 95 procedures. A single stent was used in 42 (44.2%) cases, while 52 (54.7%) aneurysms were treated with 2 stents (50 “Y” configuration, 2 “X” configuration). One case of Y stent-assisted coiling was prematurely interrupted because of aneurysm perforation. Post-treatment control angiography showed complete occlusion in 55 cases (58.5%), neck remnant in 15 cases (15.9%), incomplete occlusion in 24 cases (25.5%). The overall symptomatic peri-procedural complication rate was 13.7%. The overall morbidity rate was 4.2% (4 cases with a modified Rankin Scale >2 and <6). The overall mortality rate was 2.1% (2 cases). Fifty-six aneurysms underwent follow-up (mean follow-up: 10.5 months): 47 aneurysms (83.9%) were completely occluded, 7 aneurysms (12.5%) had a neck remnant, and 2 aneurysms (3.6%) was incompletely occluded.

Conclusion:
The Neuroform ATLAS is an effective device for treatment of complex intracranial aneurysms, allowing good conformability and high level of navigability, but with a non-negligible rate of complications.
Abstract WP12: Long-term Effect Beyond 90 Days After Endovascular Therapy
Authors: Todo Kenichi , Sakai Nobuyuki , Imamura Hirotoshi , Yamagami Hiroshi , Adachi Hidemitsu , Kono Tomoyuki , Kobayashi Junya , Yamamoto Shiro , Morimoto Takeshi , Sakaguchi Manabu , Nakamura Hajime , Kishima Haruhiko , Mochizuki Hideki , Kohara Nobuo
Published: January 2019

Background and Purpose:
Recent studies have demonstrated that endovascular reperfusion therapy improves clinical outcomes at 90 days after ischemic stroke. However, effects on long-term outcomes are not well known. The objective of the current study was to assess whether successful reperfusion was associated with a temporal change in modified Rankin Scale (mRS) score from 90 days to 1 year after endovascular therapy.

Methods:
We retrospectively analyzed a database of consecutive patients with acute ischemic stroke who received endovascular therapy between April 2006 and March 2016 at 4 centers. We compared the incidences of improvement and deterioration in patients with successful reperfusion (i.e., modified thrombolysis in cerebral infarction score of 2b or 3) with those in patients with unsuccessful reperfusion. We defined improvement and deterioration as a decrease and an increase of 1 or more points on the mRS score from 90 day to 1 year after endovascular therapy, respectively.

Results:
A total of 268 patients were included in the current study. The rate of patients with improvement tended to be higher in patients with successful reperfusion than in patients with unsuccessful reperfusion (20% [34/167 patients]
vs.
12% [12/101],
P
= 0.07). The rate of patients with deterioration was lower in patients with successful reperfusion than in patients with unsuccessful reperfusion (25% [42/167]
vs.
42% [42/101],
P
< 0.01). After adjustment for confounders, successful reperfusion was associated with improvement (adjusted odds ratio, 2.65; 95% confidence interval, 1.23-5.73;
P
< 0.05) and deterioration (adjusted odds ratio, 0.33; 95% confidence interval, 0.18-0.62;
P
< 0.01), independent of the 90-day mRS score.

Conclusions:
Successful reperfusion has further beneficial effects on long-term outcomes beyond 90 days from stroke.
Abstract WP126: A Predictive Model for Intracranial Aneurysm Growth Trajectory
Authors: Chien Aichi , Callender Rashida , Salamon Noriko , Vinuela Fernando , Ye Yuanqing , Hildebrandt Michelle
Published: January 2019

Introduction:
The rate of growth of a particular intracranial aneurysm (IA) is relevant for assessing the risk posed by the IA, and determining an appropriate management strategy. However, the rate of growth cannot currently be estimated when an IA is detected. By determining the association of various factors with IA growth rate based on longitudinally followed aneurysm data, we have developed a predictive model for the patient-specific IA growth trajectory.

Hypothesis:
If a particular IA will grow, its course of growth is largely determined by the characteristics of the patient and the IA itself.

Methods:
This study utilized a retrospective dataset of 382 patients with 520 IA diagnosed between 2005-2015. Medical images and electronic medical records were used to build the predictive model. IA were monitored for 32.7 ± 25.4 months, with a mean of three CTA image studies monitoring IA growth or lack thereof, comprising 1,636 data points. Multivariate adaptive splines for analysis of longitudinal data (MASAL) was utilized to guide the development of multivariate linear mixed models for two-level data.

Results:
MASAL showed that initial size was significantly associated with stroke, hypertension, coronary artery disease, atrial fibrillation, and diabetes mellitus. Therefore, these patient-specific factors were eliminated to avoid overfitting. Smoking history (previous or current) and diagnosis of thyroid disease were found to be independent variables for growth rate prediction and were used to build the model. Our preliminary model found different growth patterns for IA with different initial sizes. We also found that the growth rate of large IA (>7 mm) was more strongly influenced by smoking and thyroid disease. Growth of IA in patients with thyroid disease was found to slow down significantly after 24 months of follow-up, suggesting IA do not grow linearly.

Conclusions:
We present the first attempt to model IA growth based on medical data and 3D image data for aneurysm cases collected longitudinally over the past 10 years. Our results show it may be possible to predict rate of growth on an individual and aneurysm-specific basis.
Abstract WP133: Prevention of the Post-stroke Induction of Endogenous tPA Mitigates Brain Damage and Facilitates Neurological Recovery
Authors: Veeravalli Krishna Kumar , Nalamolu Koteswara Rao , Mohandass Adithya , Venkatesh Ishwarya , Klopfenstein Jeffrey D , Pinson David M , Wang David Z
Published: January 2019

Introduction:
Multiple pieces of evidence suggest that the elevated endogenous tPA (endo-tPA) levels in the brain after ischemic stroke are neurotoxic and contribute to the ongoing brain damage. The neurotoxicity of endo-tPA could be due to activation of apoptotic cell signaling processes, extracellular matrix degradation, or increase in permeability of the neurovascular unit. The purpose of this study is to investigate the effect of specific endo-tPA suppression on post-stroke brain injury and neurological recovery.

Methods:
Male Sprague-Dawley rats were subjected to a suture model middle cerebral artery occlusion (MCAO) procedure followed by reperfusion. To achieve the specific knockdown of endo-tPA, plasmids expressing shRNAs specific to rat tPA (tPAsh) formulated as nanoparticles were administered immediately after reperfusion to rats intravenously via tail vein at a dose of 1 mg/kg body weight. Untreated, and vehicle/tPAsh-treated stroke-induced rats along with sham-operated rats were sacrificed at various post-reperfusion time points. We performed various techniques such as TTC staining, real-time PCR, and immunoblot analysis to determine both the efficiency of tPAsh plasmids and efficacy of tPAsh treatment on post-stroke brain injury. To assess the effect of tPAsh treatment on post-stroke neurological recovery, we performed modified neurological severity scores, modified adhesive removal, and beam walking tests at regular intervals until 14 days reperfusion.

Results:
Endo-tPA protein expression in the ischemic brain of rats was increased until 5 days reperfusion. Treatment with tPAsh formulation reduced the protein expression of tPA in the ischemic brain of rats and thereby demonstrated the
in vivo
efficiency of plasmids expressing tPA shRNAs. The MCAO procedure-induced mortality is comparable across the cohorts. Specific knockdown of endo-tPA reduced the infarct volume and facilitated the post-stroke neurological recovery.

Conclusions:
Preventing the induction of post-stroke endo-tPA levels in rat brain attenuates ischemic brain damage and improves post-stroke neurological recovery.
Abstract WP145: Modulating Astrogliosis to Promote Neuroprotection and Plasticity After Stroke
Authors: Chen Meifan , Ingle Laura , Kong Xiangmei , Plautz Erik , Goldberg Mark P
Published: January 2019

Astrocytes react to central nervous system (CNS) injury, including stroke, with a range of molecular and functional changes known as astrogliosis. Although astrogliosis critically impacts neuroprotection and injury-dependent reorganization of the neural network associated with recovery, current lack of molecular tools to effectively manipulate astrogliosis
in vivo
greatly limits our understanding of how astrogliosis should be targeted to promote neural repair and recovery. We recently identified leucine zipper kinase (LZK) as a potent activator of astrogliosis (Chen et al,
Cell Reports
, 2018). Manipulating LZK expression in astrocytes, through the use of astrocyte-specific and inducible LZK-knockout or LZK-overexpression mice, enables specificity and versatility in reducing or enhancing astrogliosis respectively. We applied these novel genetic tools to the photothrombotic model of ischemic stroke targeted to the motor cortex in order to determine how best to modulate astrogliosis to promote neuroprotection and axonal plasticity after stroke. Our data show that CNS-systemic stimulation of astrogliosis enhanced neuroprotection, as demonstrated by a 50% reduction in infarct volume and degeneration of corticospinal axons. Furthermore, stimulating astrogliosis promoted stroke-induced axonal plasticity, as demonstrated by more than twofold increase in midline-crossing corticospinal axons originating from the uninjured hemisphere. Our findings suggest a beneficial role of LZK-regulated astrogliosis in post-stroke neuroprotection and plasticity, whose underlying molecular mechanism and therapeutic application are currently being investigated.
Abstract WP15: Safety of Dual Antiplatelet Treatment in Emergent Large Vessel Occlusion (ELVO) Patients Treated With Mechanical Thrombectomy (MT) and Extracranial Internal Carotid Artery Stenting
Authors: Ishfaq Muhammad F , Tsivgoulis Georgios , Goyal Nitin , Pandhi Abhi , Krishnan Rashi , Malhotra Konark , Krishnaiah Balaji , Nickele Christopher , Inoa Violiza , Hoit Daniel , Elijovich Lucas , Alexandrov Anne W , Alexandrov Andrei V , Arthur Adam S
Published: January 2019

Introduction:
Extracranial Internal carotid artery (ExICA) stenting may be required during mechanical thrombectomy (MT) for anterior circulation large vessel occlusions (ACLVO) with coexisting ExICA steno-occlusive disease. We sought to evaluate the safety of acute dual antiplatelet therapy (DAP) in this high-risk MT subgroup.

Methods:
Consecutive ACLVO patients treated with MT were evaluated during a five-year period. All patients receiving ExICA stenting during MT were also acutely treated with DAP coupled with heparin or eptifibatide drips. Baseline stroke severity and early hypodensity on baseline CT were assessed using NIHSS-score and ASPECTS. Complete reperfusion (CR) was defined as modified Thrombolysis in Cerebral Infarction grades IIb/III) at the end of MT. Final infarct volume (FIV) on brain MRI was assessed at 24-48 hours using standardized methodology. Safety outcomes included symptomatic Intracranial Hemorrhage (sICH) documented by SITS-MOST criteria, infarct in new unaffected territory (INT) determined according to ESCAPE trial methodology and three-month mortality. We also assessed 3-month functional outcomes using modified Rankin Scale (mRS) scores.

Results:
Among 309 ACLVO patients treated with MT, 24 received additional ExICA stenting. Eptifibatide and heparin drips were administered in 15 (65% of stenting subgroup: 9 patients: aspirin + clopidogrel, 6 patients: aspirin + ticagrelor) and 8 (35% of stenting subgroup: 6 patients: aspirin + clopidogrel, 2 patients: aspirin + ticagrelor) cases respectively. Patients with and without ExICA stenting had similar (p>0.1) median baseline NIHSS-scores (15 vs. 16 points) and ASPECTS (10 vs. 10 points). The two groups did not differ (p>0.1) in terms of median FIV (20 vs. 15 cm
3
) and median 3-month mRS-scores (2 vs. 2). Patients with ExICA stenting had similar (p>0.1) rates of sICH (5% vs. 8%), INT (0% vs. 9%), CR (74% vs. 70%) and 3-month mRS-scores of 0-2 (55% vs. 51%) compared to the rest.

Conclusions:
DAP coupled with eptifibatide or heparin drips does not appear to increase peri-procedural complications or to worsen clinical outcome of ELVO patients treated with MT and ExICA stenting.
Abstract WP152: Iron Chelation Improves Stroke Outcomes in Diabetes: Impact on Neurovascular Remodeling, Microglial Activation and Ferroptotic Endothelial Cell Death
Authors: Abdul Yasir , Jamil Sarah , Ward Rebecca , Dong Guangkuo , Li Weiguo , Fagan Susan , Ergul Adviye
Published: January 2019

Introduction:
We have shown that 1) poor recovery in diabetes is associated with greater hemorrhagic transformation (HT) and significant loss the cerebrovasculature, and 2) iron chelation therapy with deferoxamine (DFX) improves functional outcomes while preventing vasoregression in diabetic animals after embolic stroke. However, underlying mechanisms remained unknown. Current study was designed to test the hypotheses that DFX attenuates 1) microglial activation and pathological neurovascular remodeling, and 2) ferroptosis, iron-dependent cell death, of brain microvascular endothelial cells (BMVECs).

Methods:
Control and type 2 diabetic animals were subjected to embolic middle cerebral artery occlusion (MCAO). DFX (100 mg/kg) or vehicle was given 1hour after MCAO and repeated every 12 h for 7 days after stroke. At Day 14, microglial activation and neurovascular integrity were evaluated by immunohistochemical analyses of Iba1 and Aquaporin-4 (AQP4) polarity, respectively. BMVECs isolated from control Wistar and diabetic Goto-Kakizaki rats were treated with iron(III)sulfate (0.1mM) in presence/absence of DFX (100μM) for 6 hours. Cell viability and ferroptotic cell death markers like IREB2, ACSL4, MDA formation and total glutathione content were measured.

Results:
Ischemia/reperfusion injury amplified microglial activation and neurovascular remodeling in diabetes while DFX treatment reduced these changes to control levels (Table 1). DFX treatment also prevented iron-mediated cell death and decreased the expression of ferroptotic cell death markers (Table 1).

Conclusions:
Mechanisms underlying DFX-mediated improvement of sensorimotor and cognitive functions after stroke in diabetes involve attenuation of neuroinflammation, pathological neurovascular remodeling and endothelial ferroptosis. Iron chelation is a potential therapeutic strategy to improve outcomes in diabetic stroke that is associated with greater HT.
Abstract WP155: Inhibition of Ras-Related C3 Botulinum Toxin Substrate 1 (Rac1) Exacerbates Endothelial Viability and Regenerative Responses After Stroke in vitro
Authors: Bu Fan , Lai Yun-Ju , Qi Li , Arnold Frances M , McCullough Louise D , Li Jun
Published: January 2019

Brain endothelial cells play an essential role in BBB integrity and vascular recovery after injury. Accumulating evidence shows that Rac1, a Rho-related GTPase, are central in promoting endothelial vascular development. However, the contribution of endothelial Rac1 in ischemic stroke has not been directly investigated. We hypothesized that Rac1 signaling protects endothelial cells and promotes angiogenesis after stroke. Immortalized human brain endothelial cells (HBEC-5i) were challenged by oxygen-glucose deprivation (OGD) for 18 hours followed by re-oxygenation. For cell viability test, NSC 23766 (NSC, 3, 15 and 30 μM), a specific Rac1 inhibitor, was added at re-oxygenation (immediately after the18 hours ODG). The viability of endothelial cells was assessed by CCK-8 (% normoxia control) 24 hours after the18 hours OGD. For migration and tube formation assays, NSC at 30 μM was added 24 hours after the 18 hours OGD to avoid potential effects on cell survival. Cell migration using scratch assay (wound area compared to initial time %) was examined 72 hours after the 18 hours OGD. Tube formation, the ability of cells to align into tube-like structures (number of junctions), was measured 28 hours after the 18 hours OGD. Data are presented as mean±SEM. OGD reduced endothelial cell viability (control 100±3.23 vs. OGD 69.97±1.11, n=6-7, p<0.001). Acute Rac1 inhibition with NSC led to a worsening of the endothelial viability in a concentration dependent manner (3 μM: OGD+vehicle 69.97±1.11 vs. OGD+NSC 63.98±1.53, n=6, p>0.05; 15 μM: OGD+vehicle 69.97±1.11 vs. OGD+NSC 60.77, n=6, p<0.05; 30 μM: OGD+vehicle 69.97±1.11 vs. OGD+NSC 43.92±3.23, n=6, p<0.001). Using delayed treatment regimen, Rac1 inhibition reduced the endothelial regenerative responses including the cell migration assessed by the scratch assay (OGD+vehicle 9.95±2.31% vs. OGD+NSC 32.85±2.69%, n=6, p<0.001) and cell re-organization assessed by tube formation assay (OGD+vehicle 66.55±5.52 vs. OGD+NSC 33.63±6.73, n=8-11, p<0.05). In conclusion, acute inhibition of Rac1 signaling worsened endothelial cell survival and delayed inhibition of Rac1 reduced angiogenic responses after OGD. Activation of endothelial Rac1 signaling may protect BBB and promote vascular recovery after stroke.
Abstract WP158: Impact of Serum Trimethlamine N-oxide (tmao) Levels on Long-term Outcomes of Acute Stroke Patients
Authors: Ha Jimin , Kwon Il , Ji Da-Jeong , Kim Naeun , Choi Hyun-Jung , Heo Ji Hoe , Lee Sang-Kuk , Nam Hyo Suk
Published: January 2019

Backgroud:
Trimethylamine N-oxide (TMAO) is produced by gut microbiota. Gut microbiota derived TMAO are known to be associated with coronary heart disease, congestive heart failure, and chronic kidney disease. Therefore, increased TMAO may be associated stroke outcome.

Method:
Fasting blood from consecutive 313 stroke patients were analyzed. Plasma TMAO level was measured by mass spectrometry. The patients were followed up for 3 years and major adverse cardiovascular event (MACE) was captured. The cut off value was calculated by Contal & O'Quigley's method.

Results:
Median TMAO level was 362.4 (IQR 317.5 - 405.6) ng/ml. Cut off value was 563. 25. Older age, men was predominant in patients with higher TMAO level. Moderate to severe renal disease were frequent and creatinine levels were high in patient with higher TMAO group compared to lower TMAO group (1.4±1.8 vs. 0.9 ± 1.1, p = 0.047). Higher level of TMAO was associated with occurrence of MACE in Kaplan-Meier survival analysis (log-rank test, p<0.01). Multivariable Cox regression analysis showed that TMAO level was independent factor along with age, sex, hypertension, diabetes, and initial stroke severity (HR 1.712, 96% CI 1.060 - 2.767).

Conclusion:
We found that the TMAO level in patients with acute ischemic stroke was associated with poor long-term outcome. Gut microbiota and brain axis may be a prognostic marker after acute ischemic stroke.
Abstract WP162: Automatic Detection of Middle Cerebral Artery Plaque on T2-weighted Vessel Wall Imaging
Authors: Yu Yannan , Ravkic Irma , Xu Wei-Hai , Li Ming-Li , Liebeskind David , Scalzo Fabien
Published: January 2019

Background:
Intracranial vessel wall imaging (VWI) has been reported to be an efficient approach for evaluating ICAD, yet the reliability of intracranial plaque identification may vary depending on the experience of institutions or readers. We aim to automatically detect middle cerebral artery plaque on T2-weighted VWI using machine learning algorithms and thus reduce inter-reader variability.

Methods:
Patients were selected from our institutional vessel wall imaging database if they had acute stroke in the MCA territory on diffusion-weighted imaging (DWI) and MCA plaque seen on VWI, or if they had no history of stroke or transient ischemic attack and no plaque seen on VWI. Bilateral MCAs of all patients were analyzed individually. The cross-sectional images of MCA were graded into a scale of 1-3 based on the confidence of the reader regarding the presence of plaque in the cross-sections: Grade 1, the plaque is not present, used as control group; Grade 2, the plaque may or may not present, not included in further analysis; Grade 3, the plaque is present, used as plaque group. Cross-sections with insufficient image quality result from motion artifacts or with non-cross-sectional images of MCA were excluded. The annotated vessel regions on T2-weighted images were used as input to a classification algorithm based on a nonlinear spectral regression algorithm. The model was evaluated under a crossvalidation in order to predict the presence of plaque in the vessel (Grade 1 versus Grade 3).

Results:
A total of 104 patients with stroke and 27 controls were included, leading to 453 slices with plaque and 246 slices for the control group. After a 3-fold crossvalidation, the model reached an accuracy of 87.2% in detecting correctly the presence of plaque in the vessel regions.

Conclusion:
Our experiments demonstrate that a nonlinear machine learning approach can achieve high performance in detecting presence of plaque in the vessel, which is the first step in further analysis of plaque-related parameters and more objective diagnoses.
Abstract WP174: Frequency, Predicators, and Outcomes of Pre-Intervention Thrombus Migration in Patients With Acute Ischemic Stroke Due to Large Vessel Occlusion
Authors: Lee Kee Ook , Liebeskind David , Jahan Reza , Starkman Sidney , Sharma Latisha , Yoo Bryan , Avelar Johanna , Rao Neal , Hinman Jason , Duckwiler Gary , Nour May , Szeder Viktor , Tateshima Satoshi , Colby Geoffrey , Hosseini Mersedeh Bahr , Raychev Radoslav , Kim Doojin , Vespa Paul M. , Blanco Manuel M. Buitrago , Saver Jeffrey L. ,   for the UCLA Reperfusion Therapy Investigators
Published: January 2019

Background:
In patients presenting with acute ischemic stroke (AIS) due to large vessel occlusion (LVO), between initial CTA/MRA and catheter angiography performed for intervention, the occlusive thrombus may persist unchanged, fragment and migrate distally, or resolve completely, with or without bridging intravenous fibrinolytic treatment. The frequency, predictors, and outcomes of pre-intervention thrombus migration not been well delineated.

Methods:
We analyzed a prospectively maintained registry of AIS-LVO patients at an academic medical center over a 2.8 year period (Dec 2014-Oct 2017). Comparing occlusion sites on arrival CTA/MRA with immediately following interventional angiogram, patients were classified as having: 1) thrombus persistence (TP), 2) thrombus migration (TM), or 3) thrombus resolution (TR).

Results:
In the 220 patients, mean age was 70.7, 42.7% were female, NIHSS was 13.8, onset to first imaging was 156 minutes, and initial occlusion sites on MRA/CTA were: ICA-20.5%; MCA-67.3%; VA/BA-12.3%. Frequencies of thrombus evolution patterns were: TP-59.5%; TM-30.5%; TR-10.0%. On multivariate analysis, independent predictors of TM were: higher NIHSS (OR 1.06 per 1 pt), cardioembolic mechanism (OR 2.40), and longer time from last known well to first CTA/MRA imaging (OR 1.08 per 60 min). While rates of substantial reperfusion (TICI 2b-3) were similar (85.2% vs 83.7%), patients with TM rather than TP had lower rates of excellent reperfusion (TICI 2C-3), 24.1% vs 44.2%, p = 0.02. Symptomatic intracranial hemorrhage occurred more often in TM than TP, 17.9% vs 8.4%, p = 0.05. In multivariate analysis, TM was independently associated with reduced rates of good functional outcome (mRS 0-2), both at discharge (OR 0.41, 95% CI 0.19 to 0.90; p=0.03) and at 3 months (OR 0.43, 95% CI 0.19 to 0.94; p=0.03).

Conclusions:
Early TM between initial noninvasive imaging and interventional angiography occurs in nearly one-third of patients, is paradoxically associated with poorer outcomes, including more symptomatic hemorrhage and reduced final functional independence. Better understanding of dynamic clot changes early after arrival and their effects on outcome may aid further development of reperfusion therapeutics.
Abstract WP181: Linking Post-Stroke Injury, Neural Function, and Motor Behavior With EEG
Authors: Cassidy Jessica M , Wodeyar Anirudh , Wu Jennifer , Srinivasan Ramesh , Cramer Steven C
Published: January 2019

Introduction:
Elucidating the relationship between stroke-induced injury and changes in neural function may potentiate rehabilitation and treatment development. This study examined post-stroke associations between functional electroencephalography (EEG) measures, structural injury, and motor behavior.

Hypothesis:
Greater injury extent and motor impairment correspond to increasing delta band (1-3Hz) and decreasing high beta band (20-30Hz) EEG measures in a time-dependent manner.

Methods:
Subjects with stroke completed a 3-minute resting-state EEG recording, an MRI, and motor testing (Fugl-Meyer, FM). EEG power and ipsilesional primary motor cortex (M1) coherence (connectivity) were computed from dense-array EEG (194 leads). Global (lesion volume) and motor-specific (%CST injury) injury were measured on MRI. Associations between EEG measures and injury/behavior were significant if ≥10% of leads demonstrated significance (p≤0.05).

Results:
Sixty individuals (mean age 56.6 years, 11.9 months post-stroke) were stratified into subacute (n=24) and chronic (n=36) groups. For EEG power, larger delta band power correlated strongly with increasing lesion volume early after stroke, and this association expanded (21 to 82 leads) in chronic stroke to bilateral premotor, M1, and temporal-parietal regions. This delta power expansion strongly correlated with greater FM scores. For EEG coherence, larger delta band ipsilesional M1 coherence with leads overlying bilateral fronto-temporal-parietal regions strongly correlated with both greater lesion volume (64 leads) and CST injury (52 leads) early after stroke. These associations were reduced in chronic stroke but still strongly correlated with greater FM scores. Beta band power and coherence measurements showed negative and positive correlations with lesion volume, respectively, but did not relate to motor behavior.

Conclusions:
Low-frequency band EEG power and coherence measures predominantly capture global injury arising from stroke. The expansion of delta power and the reduction of delta coherence from subacute to chronic stroke are adaptive responses indicative of lower motor impairment, and these measures may prove valuable in monitoring stroke rehabilitation.
Abstract WP184: Correlation of Body Composition and Nutritional Status With Functional Recovery in Patients Undergoing Stroke Rehabilitation
Authors: Irisawa Hiroshi , Shibuya Ken-ichiro , Mizushima Takashi
Published: January 2019

Introduction:
Previous studies suggest that the nutritional status after stroke is independently associated with long-term outcome and that sarcopenia delays post-stroke rehabilitation and worsens prognosis. However, many patients who have suffered from stroke have deteriorated nutritional status and decreased muscle mass in the acute phase. Here, we assessed the correlation of body composition and nutritional status with functional recovery in patients undergoing subacute stroke rehabilitation.

Hypothesis:
Decrease in muscle mass and malnutrition will prolong functional recovery in patients undergoing stroke rehabilitation.

Methods:
This retrospective study performed in 2 stroke rehabilitation units from January 2017 to June 2018. We performed bioelectrical impedance analysis and determined the Geriatric Nutritional Risk Index (GNRI) for detecting muscle mass and nutritional status on admission. We analyzed actibities of daily living (ADL) using the Functional Independence Measure (FIM) at the time of admission and 4 weeks later. We described changes in motor FIM items and examined relationships between data.

Results and Conclusions:
The study included 179 patients (mean age 75.5 ± 13.0 years, male/female: 89/90, and mean average of 27.6 ± 8.7 days after stroke). The patients received individual stroke rehabilitation program (159.8 ± 21.6 minutes per day) 7 days a week. Multiple regression analysis revealed that patients with high body muscle percentage (skeletal muscle mass/body weight) (odds ratio = 2.42), bioelectrical impedance analysis-derived phase angle (odds ratio = 3.23), and GNRI (odds ratio = 2.57) were significantly correlated with motor FIM items at 4 weeks. In conclusion, it was clarified that muscle mass maintenance by nutritional management and early rehabilitation in the acute period of stroke is essential for functional recovery in patients who have suffered from stroke.
Abstract WP190: Ipsilesional Mu Changes Track With Behavioral Changes in UE BCI Intervention in Stroke Survivors
Authors: Remsik Alexander B , Dodd Keith , Ginji Klevest , van Kan Peter , Nair Veena , Farrar Edwarads Dorothy , Prabhakaran Vivek
Published: January 2019

Loss of motor function is a common deficit following stroke insult and often manifests as persistent upper extremity (UE) disability which can affect a survivor's ability to participate in activities of daily living. Recent research suggests the use of brain-computer interface (BCI) devices might improve UE function in stroke survivors at various times since stroke. This randomized crossover-controlled trial examines whether intervention with this BCI device design attenuates the effects of hemiparesis, encourages reorganization of functional connectivity, and improves movement, as measured by the Action Research Arm Test (ARAT). 21 stroke survivors, presenting with varied times since stroke and levels of UE impairment, received a maximum of 18 - 30 hours of intervention with a novel electroencephalogram based BCI driven functional electrical stimulator (EEG-BCI-FES) device. Driven by spectral power recordings from contralateral EEG electrodes during cued attempted grasping of the hand, the EEG-BCI-FES device modulates horizontal movement of a virtual cursor as well as facilitating concurrent FES stimulation of only the impaired upper extremity. Primary outcome measure of function, ARAT was assessed at baseline, mid-therapy, and at completion of therapy. The signed r-squared value (at the ipsilesional C4 or C3 sites) for the Mu (8-12Hz) rhythm significantly decreased in the post-therapy stage compared to the pre-therapy stage (one-tailed paired t-test: t(20)= 1.85; p = 0.039; meanPRE = -0.142; meanPOST = -0.161), while the subject attempted movements of the impaired hand. These findings suggests that as the result of the intervention sessions, the “desynchronization” of the Mu rhythm signals significantly increases post-therapy at the ipsilesional motor site and this change is related to changes in behavior as a result of intervention. BCI intervention may be an effective way of addressing the stroke recovery of a stroke impaired upper extremity.
Abstract WP192: The Effects of Sertraline on Recovery From Acute Ischemic Stroke: A Prospective Observational Study
Authors: Siepmann Timo , Stuckart Isabella , Hartmann Christian , Pallesen Lars-Peder , Barlinn Jessica , Puetz Volker , Barlinn Kristian
Published: January 2019

Introduction:
The selective serotonin reuptake inhibitors (SSRIs) fluoxetine, citalopram and escitalopram have been suggested to improve functional recovery after acute ischemic stroke (AIS) due to modulation of autonomic cardiovascular and inflammatory pathways independently of changes in depressivity. Although sertraline has shown highest degree of tolerability and efficacy among SSRIs in the treatment of depression, its effects on functional recovery from AIS remain unknown.

Hypothesis:
We hypothesized that sertraline is associated with improved functional recovery from AIS which is paralleled by alleviation of autonomic symptoms and depressivity.

Methods:
We analyzed data of an ongoing prospective observational study in AIS patients who were admitted to our stroke center from 03/2017 to 08/2018 and had no disability pre-stroke (mRS 0-1). Patients who received sertraline for post stroke depression or improvement of recovery following institutional protocol and those not receiving any SSRI were include. Assessment of cardiovascular risk factors, neurological deficits (NIHSS), symptoms of depression (Beck’s depression inventory) and autonomic disturbances (autonomic symptom questionnaire) were assessed at baseline, discharge and after three months.

Results:
We present data from 61 patients (70 [20] years, median [IQR], NIHSS: 7.0 [6.0], 23 females) receiving sertraline post-stroke and 27 untreated patients (71.0 [21.0] years, NIHSS: 5.0 [3.0], 13 females). Cardiovascular risk profiles showed no differences between groups (p=ns). Patients treated with sertraline compared to untreated patients tended to achieve favorable functional outcome (3-month mRS 0-2) and functional independence (3-month mRS 0-1) more frequently (52% vs. 41.7% and 18% vs. 12.5%, p=ns) and displayed enhanced decrease of NIHSS scores from admission to discharge (24.1% vs. 17.3%, p<0.01). On multivariate regression models, sertraline tended to predict lower severity of autonomic (p=0.08, R
2
=0.63) symptoms after 3 months, independently of depressivity.

Discussion:
Our data support the hypothesis of improved functional recovery from AIS in patients receiving sertraline de novo after AIS which might in parts be mediated by modulation of autonomic pathways.
Abstract WP199: Enhancing Perception of Self-motion After Stroke Using Virtual Reality Affects Gait Adaptation in Those With High Levels of Gait Asymmetry
Authors: Mukherjee Mukul , Sado Takashi , Motz Zachary , Fayad Pierre
Published: January 2019

Introduction:
Perception of self-motion through virtual reality (VR) provides a unique avenue to mimic natural gait while walking in rehabilitation centers or clinics. This is important for enhancing gait rehabilitation in chronic stroke survivors. In this ongoing study, stroke survivors adapted to a split-belt paradigm and perception of self-motion was provided with a VR environment.

Methods:
Chronic stroke survivors (n=31; age=60.62±15.95years) were randomly put into a VR or a Non-VR group. The recruited subjects included a wide range in lower limb Fugl-Meyer scores (11-46) and baseline gait asymmetries. Participants walked at different belt speeds for each leg such that their baseline walking asymmetries were augmented. The VR stimuli consisted of walking in virtual corridor which provided the perception of self-motion that is natural during walking. Separate ANOVAs were done to demonstrate significant effects of adaptation conditions across the VR groups. Spatiotemporal measures (step length and step time asymmetries) as correlates of adaptation were compared with baseline asymmetries using Pearson correlation coefficients.

Results:
Spatial and temporal asymmetry measures showed strong adaptation effects on the split belt paradigm. These included step length asymmetry (p<0.001), limb excursion asymmetry (p<0.001), step time asymmetry (p<0.001), and stance time asymmetry (p<0.001). Significant relationships were demonstrated for step length asymmetry in the VR group (r=0.722, p<0.05) but not the Non-VR group (r=-0.457, p>0.116). A similar effect was also shown for step time asymmetry.

Discussion:
The results of our current study indicated a greater impact of VR in stroke survivors with high levels of spatial and/temporal gait asymmetries possibly due to VR allowing a better perception of the subject’s baseline gait asymmetries. A new AHA-funded project will investigate the impact of VR specifically on those with large baseline spatio-temporal gait asymmetries in addition to investigating how perceptions of visual and gait asymmetry affect such adaptations. Determination of these new relationships will improve our understanding towards gait rehabilitation after stroke to be better stratified and streamlined for greater benefit.
Abstract WP2: Tissue Based Selection for Large Vessel Occlusion Thrombectomy Leads to Similar Functional Outcomes in Conventional (0-6 Hours) and Extended (>6 Hours) Window
Authors: Bhan Chantal , Khan Muhib , Elisevich Lee , Koehler Tracy , Singer Justin , Mazaris Paul , Deveshwar Rajeev , Raad Bassel , Zachariah Joseph , Combs Jordan , Dejesus Michelle , Scureck Raymond , Tubergen Tricia , Packard Laurel , Min Jiangyong , Mulderink Todd , Abdelhak Tamer
Published: January 2019

Background:
Recent trials have shown benefit of thrombectomy in carefully selected patients in the extended (>6 hours) window. However, it is not clear if the outcomes differ from those undergoing thrombectomy in the conventional (0-6 hours) window. We sought to evaluate if time to treatment modifies the effect of endovascular reperfusion in stroke patients with evidence of salvageable tissue on CT perfusion (CTP).

Methods:
We retrospectively analyzed data of consecutive patients who underwent thrombectomy in a single center cohort. Demographics, comorbidities, National Institute of Health Stroke Scale (NIHSS), vessel occlusion location, onset to skin puncture time, core infarct volume on initial CTP, recanalization (mTICI IIb/III) rates, final infarct volume and modified rankin scale (mRS) at 90 days were compared between patients who underwent thrombectomy in conventional (0-6 hours) and extended (>6 hour) window.

Results:
119 patients were studied of which 55% were female. Univariate analysis showed that the groups (Conventional vs. Extended) were balanced for age (p=0.37), NIHSS (p=0.35), vessel occlusion location (p=0.51), initial core infarct volume (p=0.64) and recanalization (mTICI IIb/III) rates (p=0.55). Final infarct volume (p=0.18) and favorable outcome (mRS 0-2) at 90 days (p=0.65) were similar. Shift analysis did not reveal any significant difference in 90 day outcome (p=0.34). (Figure) After adjustment; age (p=0.004) and final infarct volume (p<0.001) were predictive of favorable outcome.

Conclusion:
Tissue based selection with CTP for thrombectomy in large vessel occlusion stroke is independent of onset time for favorable functional outcome.
Abstract WP201: Electroencephalogram Based Brain Computer Interface Therapy for the Restoration of Distal Upper Extremity Motor Function in Chronic Severely Impaired Individuals
Authors: Bjorklund Erik , Remsik Alex , Dodd Keith , Jacobson Tyler , Mohanty Rosaleena , Advani Hemali , Allen Janerra D , Thoma Jaclyn M , Walczak Matt , Williams Leroy , Mazrooyisebdani Mohsen , Tellapragada Neelima , Young Brittany M , Kang Theresa J , Nair Veena A , Edwards Dorothy F , Williams Justin F , Prabhakaran Vivek
Published: January 2019

Introduction:
Many stroke survivors are often left with persistent upper extremity motor impairment that affect their overall quality of life. This study aims to evaluate the efficacy of using non-invasive electroencephalographic (EEG) based brain-computer interface (BCI) therapy to facilitate distal upper extremity motor function. Data was acquired from 18 participants ((mean age = 60 years, F = 9, M = 9, 5 = sub-chronic (over 1 year from stroke onset), 13 = chronic (less than 1 year)). Behavioral outcomes were measured using the Modified Ashworth Scale (MAS), a Motor Activity Log (MAL), and the Stroke Impact Scale (SIS). We investigated whether severely-impaired, chronic stroke survivors could use BCI treatment to recover from stroke at a rate similar to that of severely-impaired, sub-chronic stroke survivors after BCI intervention.

Methods:
EEG data was acquired using BCI2000 software and 16 channel EEG cap with electrodes positioned according to the standard 10-20 system over the sensorimotor cortex at C3 & C4. Participants were cued to move either their left or right hand to control a cursor towards the right or left side of a monitor. Data acquired at baseline (no more than one week prior to BCI therapy) and post-therapy (no more than one week following BCI therapy) were used in this analyses.

Results:
No significant decrease in improvement in the chronic group compared to the sub-chronic group (0.95 confidence interval) was observed. The chronic group showed significant improvement in their affected arm in: MAS elbow flexion (p = 0.03746), MAS finger extension (p = 0.01896), MAL arm use (p = 0.02065), MAL how well they could use their arm (p = 0.02065), SIS perceived strength (p = 0.04105), and SIS arm use for daily life tasks (p = 0.01741).

Conclusion:
For chronic stroke survivors, BCI intervention for restoration of upper extremity motor function may promote recovery at a rate similar to that of sub-chronic survivors.
Abstract WP208: Advanced Liver Fibrosis and Stroke Risk in the REasons for Geographic and Racial Differences in Stroke Study
Authors: Parikh Neal S , Koh Insu , VanWagner Lisa B , Elkind Mitchell S , Zakai Neil A , Cushman Mary
Published: January 2019

Introduction:
Advanced liver fibrosis (ALF), particularly due to nonalcoholic fatty liver disease (NAFLD), is associated with high cardiovascular mortality, but its relationship with stroke is unknown. We hypothesized that ALF is associated with incident stroke risk in a national sample.

Methods:
We used a case-cohort design to assess the association between ALF and stroke in the REasons for Geographic and Racial Differences in Stroke Study. Participants (n=30,239) were recruited between 2003 and 2007 and outcomes prospectively ascertained over a mean of 4.3 years. We excluded participants with baseline stroke and alcohol abuse. Liver enzymes were measured on baseline samples for cases and a cohort random sample (CRS). The Nonalcoholic Fatty Liver Disease Fibrosis Score (NFS) and the Fibrosis-4 (FIB4) score were calculated using baseline data. ALF and its absence were defined using validated cutoffs for each score; the reference group was individuals without ALF. Outcomes were ischemic stroke and hemorrhagic stroke. Weighted Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for effect of ALF on outcomes. Models were adjusted for demographics, stroke risk factors, antithrombotic use, and an age*race interaction term. Interactions of ALF by sex were tested.

Results:
There were 608 incident strokes (536 ischemic, 72 hemorrhagic) and 959 stroke-free participants in the CRS. The prevalence of ALF was 19.5% when defined by the NFS and 5.1% by FIB4. ALF was not associated with ischemic stroke using the NFS (HR 1.76; 95% CI 0.67-4.61) or FIB4 (HR 1.44; 95% CI 0.49-4.28). Effect modification by sex was not observed for ALF defined by the NFS (P=0.71), but ALF defined by FIB4 was associated with an increased risk of ischemic stroke for women (HR 3.51; 95% CI 1.00-12.34) but not men (HR 0.70, 95% CI 0.16-3.16) (P=0.098 for interaction). Hemorrhagic stroke was too rare to model.

Conclusion:
In a national cohort, ALF was not associated with ischemic stroke overall, but there was an increased risk among women when ALF was defined using the FIB4 score. Further study in larger cohorts with more direct and precise measures of liver disease is warranted.