bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP228: Circadian Rhythm and the Severity of Ischemic Stroke
Authors: Deng Wenjun , Liu Kai , Black-Schaffer Randie , Fisher Lindsay , Chou Richard , Wang Andrew , McMullin David , Buonanno Ferdinando , Lo Eng H , Ning MingMing
Published: January 2019

Background:
The circadian variation of stroke onset has been recognized for decades, and the temporal pattern of stroke onset time, stroke subtypes, first-ever and recurrent stroke has been extensively investigated all over the world. However, little information is available regarding the circadian rhythm of stroke severity. In the present study, we investigated the relationship between stroke onset time and severity on admission in patients with acute ischemic stroke.

Method:
305 patients admitted with acute ischemic stroke were consecutively recruited in accordance with IRB approval. Stroke onset time was determined by a neurologist, by questioning patients and/or relatives who observed the onset and who were aware of the last time seen well. Stroke severity was determined by NIH stroke scale (NIHSS) on admission.

Result:
100 patients (32.79%) developed ischemic stroke at night (8pm~8am), and 205 (67.21%) had strokes during the day (8am~8pm), which is consistent with previous reports that more patients suffer ischemic strokes while awake than while asleep. Daytime strokes were also more severe than those that occurred at night (Figure 1A and 1B). Patients who developed strokes in the afternoon demonstrated the worst functional status (Figure 1C).

Conclusion:
Our results explore the circadian variation of the severity of ischemic stroke, which has important therapeutic implications in light of new advances in IA therapy. Further study is ongoing to adjust for confounders such as treatment variation, co-morbidities, social factors, and stroke subtypes.
Abstract TP235: Risk Factors for Infarct Expansion Are Different Between Lacunar and Giant Lacunar Infarction
Authors: Sato Takeo , Sakai Kenichiro , Komatsu Teppei , Sakuta Kenichi , Terasawa Yuka , Omoto Shusaku , Mitsumura Hidetaka , Iguchi Yasuyuki
Published: January 2019

Background and Purpose:
The purpose of this study was to determine risk factors for lacunar and giant lacunar infarction and to clarify differences in pathophysiological mechanisms for these two groups.

Methods:
Patients were selected from a comprehensive stroke center with ≤24 h from onset to initial magnetic resonance imaging (MRI) with lacunar and giant lacunar infarction. All patients underwent second MRI during hospitalization. Infarct expansion was defined as present when the area of the diffusion-weighted imaging (DWI)-positive region on second MRI exceeded that on the initial MRI. To calculate the area of the DWI-positive region, we manually traced each region of interest and calculated the DWI-positive region area in each slice. Infarct size was calculated and compared by the positive region on DWI. Factors related to infarct expansion were evaluated separately in the two groups.

Results:
We screened 950 consecutive ischemic stroke patients, including 106 patients with small vessel disease (lacunar infarction, 54 patients; giant lacunar infarction, 52 patients). High cardio-ankle vascular index (odds ratio, 6.255; 95% confidence interval, 1.791-21.846;
p
= 0.004) was independently associated with infarct expansion in lacunar infarction patients (Figure 1A). Concerning giant lacunar infarction, high concentration of low-density lipoprotein-cholesterol (odds ratio, 1.923; 95% confidence interval, 1.158-3.194;
p
= 0.012) and low/normal body mass index (odds ratio, 0.714; 95% confidence interval, 0.515-0.989;
p
= 0.042) were factors independently associated with infarct expansion (Figure 1B).

Conclusions:
Risk factors for infarct expansion differed between lacunar and giant lacunar infarction. The underlying pathophysiological mechanisms for infarct expansion in these two groups should be recognized individually.
Abstract TP236: Cardio-ankle Vascular Index Is Related To The Predicted 10-year Stroke Risk In Middle-aged Japanese Individuals
Authors: Nishiyama Yasuhiro , Muraga Kanako , Otsuka Toshiaki , Kato Katsuhito , Nagayama Hiroshi , Kimura Kazumi
Published: January 2019

Background:
The cardio-ankle vascular index (CAVI), which is a novel parameter of arterial stiffness has recently been known as a surrogate marker for cardiovascular diseases. However, whether CAVI levels are related to the risk of stroke in the Japanese general individuals remains unclear.

Methods:
We examined 280 Japanese subjects (92 female, mean age, 52.6 ± 5 years) with no history of cardio-cerebrovascular disease. Each subject’s CAVI level and various risk factors were assessed; the predicted 10-year stroke risk was calculated using the point-based prediction model from the Japan Public Health Center study, which consists of six risk factors (age, sex, smoking status, BMI , BP and DM are used to calculate the predicted risk of stroke.

Results:
The subjects were divided into four groups based on predicted stroke risk: low, <1%; low-medium, 1- <5%; medium, 5-<10%; medium-high, ≥10%; and high. In a multiple linear regression analysis, sex, age, BMI and systolic BP were significant independent determinants of CAVI levels. When the subjects were divided into four groups based on predicted stroke risk, according to the JPHC study risk prediction algorithm, CAVI levels were significantly higher in the high-predicted risk group than in the medium-low and low-predicted risk groups. A significant odds ratio (OR) for very high predicted stroke risk (10-year risk ≥10%) was noted in the highest quartile of CAVI levels (OR, 13.76; 95% CI, 3.06-61.99), compared with the lowest quartile, after adjusting for potential confounding factors. A significant OR for high-predicted stroke risk was also found for each quartile increase (adjusted OR, 2.85; 95% CI, 1.80-4.53) and 1-point increase (adjusted OR, 2.23; 95% CI, 1.54-3.23) in CAVI level.

Conclusion:
Elevated CAVI levels were significantly associated with an increased predicted stroke risk, suggesting that measuring CAVI may be useful for identifying Japanese individuals with a high risk of stroke.
Abstract TP238: Detecting Intraplaque Hemorrhage in Carotid Ultrasound Using Machine Learning
Authors: Yeo Leonard L , tu Tian Ming , Selvaraj Vinitha , Monajemi Sadaf , Mohammadzadeh Milad , Tan Benjamin , Sharma Vijay
Published: January 2019

Aim:
Intraplaque hemorrhage increases the risk of stroke in patients with carotid artery atherosclerosis. Magnetic resonance imaging (MRI) is more accurate in detecting intraplaque hemorrhage, but ultrasound is cheaper and widely available. Nonetheless, detecting intraplaque hemorrhage in ultrasound is difficult even for expert clinicians. We evaluate the ability of an automated software that uses machine learning (See-Mode Technologies, Singapore) to improve intraplaque hemorrhage detection in b-mode ultrasound.

Methods:
100 longitudinal b-mode ultrasound images of carotid artery were retrospectively analyzed using an automated vascular analysis software according to a blinded protocol. Two neurosonologists assessed the corresponding MRI images of the patients and confirmed the presence of intraplaque hemorrhage in 50 of these ultrasound images based on MRI. Using this dataset, a 2-class support vector machine classifier was trained to detect intraplaque hemorrhage in ultrasound images. Intensity and texture features were used for classification of ultrasound images and the performance of the classifier was assessed against intraplaque hemorrhage identified in MRI. 5-fold cross validation was then used to assess the accuracy of the classifier.

Results:
The software detected intraplaque hemorrhage in b-mode ultrasound images with high accuracy. The classification accuracy on the 100 ultrasound images was 80% for the software, while it was on average 62% for two neurosonologists (61% and 63%) assessing the ultrasound images blinded to the MRI labels. The classifier has a sensitivity of 82% and specificity of 78% in detecting intraplaque hemorrhage in b-mode ultrasound when compared against MRI.

Conclusion:
Interpretation of ultrasound images for intraplaque hemorrhage can be difficult for both experts and machine learning methods. Our proposed method benefits from learning from MRI in the training phase and applies it on ultrasound during the test phase. The machine learning method is implemented in an automated software and accurately detect intraplaque hemorrhage in ultrasound images, which can be used to increase confidence in management of patients with carotid artery atherosclerosis.
Abstract TP24: Impact of Pretreatment With Intravenous Thrombolysis on Reperfusion Status in Emergent Large Vessel Occlusion (ELVO) Patients Treated With Mechanical Thrombectomy (MT)
Authors: Goyal Nitin , Tsivgoulis Georgios , Pandhi Abhi , Krishnan Rashi , Malhotra Konark , Ishfaq Muhammad , Krishnaiah Balaji , Nickele Christopher , Inoa Violiza , Hoit Daniel , Elijovich Lucas , Alexandrov Anne , Alexandrov Andrei , Arthur Adam
Published: January 2019

Introduction:
It currently remains unclear whether pre-treatment with intravenous thrombolysis (IVT) provides any additional benefits to emergent large vessel occlusion (ELVO) patients undergoing mechanical thrombectomy (MT). We sought to evaluate the impact of pretreatment with IVT on the rate and the speed of complete reperfusion (CR) in LVO patients treated with MT in a high-volume tertiary care stroke center.

Methods:
Consecutive ELVO patients treated with MT during a five-year period were evaluated. Baseline stroke severity was assessed by NIHSS-score. Standard safety [symptomatic Intracranial Hemorrhage (sICH) by SITS-MOST definition] and efficacy outcomes [CR (modified Thrombolysis in Cerebral Infarction IIb/III), 3-month functional independence (FI; modified Rankin Scale scores of 0-2)] were compared between patients who underwent combined IVT and MT (IVT+MT) vs. direct MT (dMT). The elapsed time between groin puncture to beginning of reperfusion (GPTBRT) and the numbers of device passes (DP) required to achieve CR were also documented.

Results:
A total of 287 and 132 patients were treated with IVT+MT and dMT respectively. The IVT+MT group had higher CR (74% vs. 63%; p=0.023) and FI (52% vs.38%; p=0.008) rates and shorter median GPTBRT (48 vs. 70 min; p<0.001). The two groups did not differ in sICH rates (7% vs. 9%; p=0.368). Among patients who achieved CR, the median number of required DP was lower in the IVT+MT subgroup (1 vs. 2; p<0.001) and the rate of patients requiring ≤2 DP was higher (98% vs. 77%; p<0.001). IVT+MT was independently related to higher odds of CR (OR:1.64; 95%:1.03-2.61; p=0.036) and shorter GPTBRT (unstandardized linear regression coefficient: -20; 95%CI: -12, -27; p<0.001) on multivariable analyses adjusting for potential confounders including demographics, vascular risk factors, collateral status, stroke severity, location of occlusion and onset to groin puncture time. Among patients with CR, IVT+MT was independently associated with higher likelihood of ≤2 DP (OR:14.75; 95%:4.72-46.04; p<0.001).

Conclusions:
IVT pretreatment increases the rates of CR and shortens the duration of endovascular procedure by requiring fewer DP in ELVO patients treated with MT.
Abstract TP240: Non-Stenotic Cervical Carotid Plaque is More Common in Patients With ESUS
Authors: Siegler James E , Woo John , Messé Steven R , Cucchiara Brett
Published: January 2019

Background:
One in 5 strokes have an embolic appearance but with no clear source (ESUS). Recent data have suggested anticoagulation is no better than antiplatelet therapy in preventing stroke recurrence in these patients, arguing against a cardioembolic mechanism. It is possible that non-stenotic cervical arterial plaque may be a mechanism of stroke in some patients with ESUS.

Methods:
A retrospective cohort of consecutive adults admitted with stroke to 3 hospitals was queried (08/2015 - 05/2017). Patients with acute, unilateral, anterior circulation infarcts who underwent CT angiography of the neck within 10 days of admission and were diagnosed with ESUS or a cardiac source of embolism (CE) were included, as determined by the modified TOAST criteria. The pre-specified primary outcome was moderate plaque (≥3mm), as defined in a recently published cohort of ESUS patients, and was compared between ipsi- and contra-lateral ICAs. Plaque features and degree of stenosis were secondary outcomes.

Results:
Of 786 screened patients, 97 patients with ESUS (12%) and 115 patients with CE (14%) were included. The median age was 71y (IQR 60-81) and 117 were female (54%). Moderate plaque was more frequently ipsilateral than contralateral to the infarct in patients with ESUS (42% vs. 30%, p
McNemar
=0.03) but not in CE (37% vs. 33%, p=0.53). There was no meaningful ICA stenosis for either side in the cohort (median stenosis 0% [IQR 0-10%]), nor was there a difference when sides were compared among patients with ESUS (median 0 vs. 0%, p=0.85) or patients with CE (0 vs. 0%, p=0.343).

Conclusion:
In this cohort, there was more moderate cervical ICA plaque ipsilateral to infarcts in patients with ESUS, but not in patients with CE, suggesting an underlying atherothromboembolic mechanism for some. As such, among ESUS patients, those with ipsilateral, non-stenotic ICA plaque may not benefit from anticoagulation compared to antiplatelet therapy to prevent recurrent stroke.
Abstract TP243: Relationship of Neutrophil-to-Lymphocyte Ratio to Stroke Subtype and Functional Outcome in Intracranial Artery Dissection
Authors: Yi Kenichiro , Miwa Kaori , Mizoguchi Tadataka , Irie Kenichi , Makita Naoki , Chikuie Hidekazu , Satow Tetsu , Takahashi Jun C , Yamagami Hiroshi , Ihara Masafumi , Toyoda Kazunori , Koga Masatoshi
Published: January 2019

Background and Purpose:
Spontaneous intracranial artery dissection (IAD) might be an underdiagnosed cause of stroke that is defined by the occurrence of a hematoma in the wall of an intracranial artery and develop either ischemic or hemorrhagic stroke, but it is not known about parameters to distinguish ischemic stroke from hemorrhagic stroke. Several studies demonstrated that the neutrophil-to-lymphocyte ratio (NLR) is associated with adverse outcomes in patients with stroke at the time of occurrence. We investigated (i) the association between NLR and stroke subtype, and (ii) the clinical impact of NLR on functional outcome at 3 months after IAD.

Methods:
We retrieved data on consecutive patients with IAD within one month from onset from prospective cohort databases from February 2011 to November 2016. All patients who were clinically diagnosed with IAD accompanying ischemic or hemorrhagic stroke, or headache alone were principally admitted. We measured WBCs subtype at admission, and examined the relationship between NLR, stroke subtype, and 3-months functional outcome (mRS 0-2 vs 3-6) using logistic regression analysis.

Results:
Of the total 105 patients with IAD (mean age, 52±2; 30% men), 6 with recurrent IAD and 6 with both hemorrhagic and ischemic stroke were excluded. One patient was also excluded because of missing blood data. Of the remaining 92 patients with IAD analyzed, 33 patients (36%) had ischemic stroke, 34 patients (37%) had hemorrhagic stroke, and 25 patients (27%) had headache alone. In univariate analyses, higher median admission NLR values were documented in patients with hemorrhagic stroke (4.76; IQR, 2.11-13.34) versus patients with headache alone (3.00; IQR, 1.67-4.95); P=0.015), and versus patients with ischemic stroke (3.02; IQR, 1.67-4.95; P=0.02). In multivariate analysis adjusting for age, sex and current smoking, NLR was associated with hemorrhagic stroke [odds ratio (OR) 2.29, 95% CI 1.32-4.00]. After adjustment for age and sex, NLR was independently associated with unfavorable functional outcome (mRS 3-6).

Conclusions:
NLR appears to be a potential predictor of stroke subtype, especially subsequent hemorrhagic stroke, in patients with IAD.
Abstract TP244: Angiographic Findings Associated With Ischemic and Hemorrhagic Stroke in Intracranial Artery Dissection
Authors: Mizoguchi Tadataka , Miwa Kaori , Yi Kenichiro , Irie Kenichi , Makita Naoki , Chikuie Hidekazu , Satow Tetsu , Takahashi Jun C , Yamagami Hiroshi , Ihara Masafumi , Toyoda Kazunori , Koga Masatoshi
Published: January 2019

Background and Purpose:
Intracranial artery dissection (IAD) can cause subsequent ischemic stroke, hemorrhagic stroke or both. Although radiological findings of IAD widely include aneurysmal dilatation, segmental stenosis, or occlusion, it is unclear to what extent of each finding related to incident stroke. We tested whether findings by digital subtraction angiography (DSA) assessments were associated with increased risks of ischemic and hemorrhagic stroke in patients with IAD

Methods:
We retrieved data on consecutive patients with IAD within one month from onset who underwent DSA from single-center prospective cohort databases from February 2011 to November 2016. DSA was used to determine fusiform or irregular aneurysmal dilation, intimal flap or double lumen, and pearl-and-string sign according to proposed imaging diagnostic criteria. We assessed clinical and radiographic variables associated with IAD and subsequent stroke subtypes using logistic regression analyses.

Result:
Of the total 105 patients with IAD (mean age, 52±2 years; 30% men), 92 patients had DSA assessments. Among them, 36 patients had acute ischemic stroke (AIS) or transient ischemic attack (TIA) and 40 patients had subarachnoid hemorrhage (SAH). In multivariate analysis, current smoking (odds ratio [OR], 2.78; 95% confidence interval (CI), 1.00-8.00) and string sign (stenosis) (OR 3.24, 95% CI, 1.04-10.81) were associated with AIS/TIA, whereas intimal flap (OR, 15.44; 95% CI, 5.05-55.73) and irregular aneurysm dilatation (OR, 24.94; 95% CI, 7.34-119.04) were associated with SAH.

Conclusion:
Patients who developed AIS/TIA were related to current smoking and string sign, and patients who developed SAH were related to intimal flap and fusiform or irregular aneurysmal dilatation.
Abstract TP246: Thin Slice Ct Angiography is Useful for Detecting Aortic Arch Disease in Ischemic Stroke Patients
Authors: Ogura Shiori
Published: January 2019

Purpose:
Aortic arch disease is an important embolic source of ischemic stoke. To evaluate aortic arch disease, CT angiography (CTA) and transesophageal echocardiography (TEE) have been regularly examined. Recently, thin slice CTA is used for evaluating coronary artery disease. Thus, we considered that thin slice CTA was also useful for detecting aortic arch disease. The aim of this study was to assess the usefulness of thin slice CTA in the evaluation of the aortic arch disease and to compare with that of TEE.

Methods:
We retrospectively enrolled acute ischemic stroke patients admitted to our hospital within 7 days of onset, from October 2016 to June 2018. The findings detected by thin slice (0.5-1.0mm) CTA were evaluated by two stroke specialized neurologists. The presence and localization of plaques and ulcers were evaluated. These findings were compared to those of TEE in case of which both examinations were underwent.

Results:
We enrolled 60 acute ischemic stroke patients (37 men, mean age 70 years) who underwent CTA. Large artery atherosclerosis was detected in 17 patients (28%), and atrial fibrillation was found in 6 patients (10%). CTA was mostly examined for searching embolic sources. Plaques of 4mm or more and ulcers were found in 29 (48%) and 22 patients (37%). Accordingly, 14 patients (23%) were diagnosed as aortagenic stroke. Among 29 patients with both examinations, plaques were detected in 22 patients (76%) by CTA and in 16 patients (55%) by TEE. The sensitivity and negative predictive value of TEE in detecting plaques compared with CTA was 73% and 100%. Plaques missed by TEE were mostly located on the side close to esophagus. Ulcers were highly investigated by CTA than by TEE (45% v.s. 17%, p<0.05). The sensitivity and negative predictive value of TEE in detecting ulcers compared with CTA was 31% and 94%.

Conclusion:
In this study, thin slice CTA was superior to TEE for detecting plaques located on the side close to esophagus and ulcers. Thin slice CTA may be useful for detecting embolic sources in ischemic stroke patients. 
Abstract TP247: High Prevalence of Moyamoya Syndrome in Appalachia: Increased Frequency of Autoimmune Disorders
Authors: Nisiewicz Michael J , Dobbs Michael R , Kitzman Patrick , Wolfe Marc , Elkins Kelley , Fraser Justin F
Published: January 2019

Introduction:
Moyamoya is a chronic cerebrovascular condition of unclear etiology characterized by progressive occlusion of one or both internal carotid arteries with neovascular collateral formation. With both a congenital juvenile form and a likely secondary adult form (moyamoya syndrome), it can cause ischemic and hemorrhagic stroke. Recent findings in the region have challenged traditional estimates of its incidence in US populations. Using the Kentucky Appalachian Stroke Registry (KApSR), our aim was to further characterize its incidence as a cause of stroke, and to understand the particular patient population in our region.

Methods:
A retrospective review was performed of patients identified with moyamoya within the KApSR database. Data collected included demographics, risk factors, comorbidities and healthcare encounters from January 1, 2012 to December 31, 2017. Statistical analyses were completed in SPSS 24 (IBM Corp., Armonk, NY, USA).

Results:
Sixty-seven patients were identified; 36 (53.7%) resided in Appalachian counties. The cohort accounted for 125 of 6305 stroke admissions, representing a prevalence of 1983 per 100000 stroke admissions. Most patients presented with ischemic strokes rather than hemorrhagic (OR 5.50, 95% CI:2.74-11.04, p<0.0001). Eleven patients (16.4%) exhibited autoimmune disorders. Compared to the general population autoimmune disorder prevalence of 4.5%, the presence of autoimmunity within the cohort was significantly higher (p<0.0001). Comparing Appalachian to non-Appalachian, Appalachian patients tended to present with lower frequencies of tobacco use (p=0.073), diabetes mellitus (p=0.086), hypertension (p=0.141) and autoimmunity (p=0.322).

Conclusion:
The prevalence of moyamoya accounts for a significant portion of stroke admissions in Appalachia and these patients were more likely to develop an ischemic stroke than hemorrhagic. Autoimmune disorders were more prevalent in moyamoya patients compared to the general population. Finally, the reduced frequency of risk factors within the Appalachian group suggests an etiology distinct to the population.
Abstract TP248: Distribution and Number of Cerebral Microhemorrhages Differ According to Ischemic Stroke Subtype
Authors: Mac Grory Brian , Paddock John , Burton Tina , Cutting Shawna , Sacchetti Daniel , Dakay Katarina , Reznik Michael , Wendell Linda , Thompson Brad , Jayaraman Mahesh , McTaggart Ryan , Mahta Ali , Furie Karen , Schrag Matthew , Yaghi Shadi
Published: January 2019

Introduction:
Cerebral microhemorrhages/microbleeds (CMBs) are foci of hemosiderin deposition that appear as well-circumscribed hypointensities on T2*-weighted gradient echo magnetic resonance imaging(1). They are a bio marker of small vessel disease but may also be seen as a consequence of thromboembolism to the brain and are commonly seen in the wake of acute ischemic stroke(2). We sought to understand the relationship between CMB burden and distribution and ischemic stroke subtype.

Methods:
We undertook a retrospective observational study of patients admitted for management of acute ischemic stroke via clinical data archived as part of an institutional quality improvement project. Patient information was gathered including demographics, past medical history, treatment and ischemic stroke subtype. T2*/GRE imaging was inspected and the presence or absence, number and distribution of definite CMBs (according to Microbleed Anatomic Rating Scale (MARS) criteria(3) was documented for each patient.

Results:
695 patients with acute ischemic stroke confirmed on imaging had T2*/GRE imaging of adequate quality. The mean age in our population was 71.14 (+-15.28). 22.3% of the population had CMBs and the average number of CMBs per person was 0.66. The mean number of CMBs was higher in patients with stroke of small vessel etiology (mean of 1.97) compared with the group as a whole and this difference persisted after adjusting for age and hypertension (p=0.024). Patients with stroke of cardioembolic etiology had a higher proportion of lobar microhemorrhages (11.83%) compared with those with stroke of small vessel etiology (6.90%) though this difference did not persist after adjusting for age.

Discussion:
Distribution and number of CMBs differ based on stroke pathophysiology. CMB pattern may aid in distinguishing strokes of small vessel etiology from other ischemic stroke subtypes.
Abstract TP249: Functional MRI Guided Navigated TMS to Pharyngeal Motor Cortex
Authors: LI Shasha , Tian Qiyuan , Ahveninen Jyrki , Khan Sheraz , Wang Qingmei , Joutsa Juho , Huang Susie , Kong Jian , Rosen Bruce , Nummenmaa Aapo
Published: January 2019

Introduction:
Optimization of the precise pharyngeal TMS target within the largest-scale central swallowing networks has been complicated. We addressed this by using state-of-the art fMRI and DTI combined with navigated transcranial magnetic stimulation(nTMS).

Hypothesis:
We hypothesized that by recording sEMG of lip orbicularis oris (OO) muscles with fMRI-guided nTMS will allow us readily to detect submental complex (SMC) muscles MEP to localize swallowing hotspot in M1.

Methods:
8 healthy volunteer subjects (age = 25.714 ± 4.35, males: 2) conduced a voluntary saliva swallowing task modified from our previous study and a similarly sequenced lips pursing task. MEMPRAGE, HARDI as well as standard rsfMRI were performed to assess structural and functional connectivity. The motor cortices of the SMC and OO muscles in each hemisphere were targeted with a TMS neuronavigation that used a graphic user interface and a 3D optical digitizer to precisely position the coil over the cortical site based on individual swallowing/lips-task fMRI target. SMC and lip OO sEMG responses were detected with bipolar electrodes.

Results:
The fMRI-guided navigated (Figure 1 A and B) lips target was identified by the resting motor threshold compared with a traditionally measured hotspot (Figure 1 C and D). The simultaneous SMC response was detected to further clarify the estimate of the swallowing hotspot (Figure 1 E). The functional patterns of swallowing and connectivity in each hemisphere are demonstrated using resting fMRI combined fiber tractography (Figure 1 F, G, H and I).

Conclusions:
We provide evidence for the more precise and reliable targeting of pharyngeal motor cortex with the combination of fMRI and DTI and the assistance of fMRI-guided TMS on lips. This multimodal neuroimaging approach will enable visualization of a precise neuronal biomarker of central swallowing and thus allow the development of effective direct clinical treatment strategies for neurogenic swallowing disorders.
Abstract TP25: Features of Patients With Stroke Receiving Intracranial Balloon Angioplasty for Secondary Prevention in Comparison to Rescue Recanalization
Authors: Toshi Sai , Keisuke Imai , Masashi Hamanaka , Masahiro Itsukage , Kazuma Tsutou , Atsushi Yamamoto , Tetsuya Ioku , Masanori Cho , Kanako Menjo , Hidekazu Yamazaki
Published: January 2019

Background:
Susceptibility to intracranial atherosclerosis is a unique feature of stroke in Asian patients. Intracranial percutaneous transluminal balloon angioplasty/stenting (IC-PTAS) is an important therapy for secondary prevention and rescue in such patients.

Objective:
The purpose of this study is to clarify features of Japanese patients with stroke receiving IC-PTAS for secondary prevention or for rescue recanalization.

Methods:
Medical records of 116 consecutive stroke patients treated with IC-PTAS at our hospital from April 2006 to May 2018 were retrospectively reviewed. The patients were divided into secondary prevention (P) and rescue (R) groups based on the purpose of IC-PTAS. Backgrounds, procedures, andtechnical and clinical outcomes were compared between the groups.

Results:
In groups P (n=60, male=40) and R (n=56, male=35), the mean ages were 70 and 72 years, the median times from ischemic events to IC-PTAS were 21 and 0.5 days, the mean stenotic ratios were 84.6% and 97.9%, the number of cases with morphology suitable for IC-PTAS (modified Mori class A or B1) were 35 and 8, and the distributions of treated vessels (extradural ICA, intradural ICA, MCA, BA, VA, others) were 31, 6, 11, 5, 5, 2, and 4, 14, 24, 6, 5, 3, respectively. In groups P and R, stents were deployed in 26 (43%) and 23 (41%) cases, technical success was achieved in 60 (100%) and 48 (86%) cases, the mean residual stenotic ratios were 27.6% and 40.3%, and there were major complications in 4 (7%) and 6 (12%) cases, stroke within 30 days in 4 (7%) and 6 (12%) cases, and symptomatic intracranial hemorrhage in 0 and 1 cases, respectively.

Conclusion:
Stroke patients receiving IC-PTAS for secondary prevention in Japan have a longer interval between the ischemic event and the procedure and a higher number of safer lesions, such as those with a lower stenotic ratio, suitable morphology, and an intradural site, compared to patients who receive this treatment for rescuerecanalization. This might result in favorable technical and clinical outcomes for patients receiving IC-PTAS in Japan.
Abstract TP254: Frequent Flyers: Retrospective Review of Repeat Stroke Codes
Authors: Tantillo Gabriela , Wheelwright Danielle , Dhamoon Mandip , Leung Kenneth , Tuhrim Stanley , Stein Laura
Published: January 2019

Introduction:
A stroke code is a standardized pathway for rapidly assessing patients with possible stroke. Inpatients with neurological deficits often trigger repeat stroke codes, even if the etiology is not vascular. We analyzed all repeat stroke codes to look for trends in diagnosis, timing and risk factors as part of a departmental quality improvement project aimed at improving policy in light of new acute stroke treatment guidelines.

Methods:
We analyzed all stroke codes in our urban, multi-hospital healthcare system by reviewing all cases where an acute stroke code head CT was ordered from January 2017 to April 2018. Patients for whom >1 stroke code was called during the period of interest were analyzed for final diagnosis, timing between stroke codes, and underlying medical and vascular risk factors. A diagnosis of stroke was confirmed by imaging with either CT or MRI.

Results:
There were 651 stroke codes in total, of which 51 were called on the same patient, representing 8% of all codes. 68.3% of all codes had a confirmed stroke or TIA, and 49% had a history of prior stroke or TIA. These 51 codes were represented by just 25 patients, one of whom triggered 3 stroke codes in one year, and the rest triggering 2. 61% were found to have a stroke the first time as well as the second time the code was called. Among these repeat strokes, 34.1% had atrial fibrillation, 31.4% had critical vascular stenosis and 14.3% had underlying malignancy. Patients without an acute stroke included those with toxic metabolic encephalopathy (21.6%) and seizure/post-ictal state (9.8%). 45.5% of toxic-metabolic patients had ESRD with an equal percentage having uncontrolled blood sugar. The average time between repeat stroke codes was 61.3 days. The average time between repeat stroke codes in patients who had a stroke both times was 17.67 days.

Conclusions:
We found that patients with a history of stroke remain at high risk for a repeat stroke in a short period of time, reflected by a time to repeat stroke code on confirmed patients of less than 3 weeks. Of these, a large proportion (65.5%), were found to have either atrial fibrillation or critical vascular stenosis. These patients may merit closer monitoring during the first month as they remain at high risk of further vascular events.
Abstract TP255: Assessment of Hemodynamic Changes in Persistent Carotid-Vertebrobasilar Anastomoses by Ultrasonography
Authors: Yang Jie , Hua Yang , Li Qiuping
Published: January 2019

Objectives:
Persistent carotid-vertebrobasilar anastomoses (PCVBA) is a rare cerebral arterial variant between anterior and posterior circulation. This study aimed to evaluate the hemodynamic characteristics of PCVBA by the combination of color Doppler flow imaging (CDFI) and transcranial color-coded sonography (TCCS).

Methods:
Patients diagnosed with PCVBA were imaged by combination of CDFI and TCCS, then confirmed by digital subtraction angiography (DSA) or computed tomography angiography (CTA) from July 2015 to July 2017. The parameters, including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI), were acquired in extracranial vertebral artery (VA), intracranial VA, basilar artery and posterior cerebral artery. The vessel diameter of the extracranial VA was measured as well.

Results:
A total of 14 patients were analyzed in this study. Posterior ischemic stroke associated with ipsilateral internal carotid artery (ICA) atherosclerosis were found in 3 patients (3/14, 21.4%), and posterior transient ischemic attack occurred in 8 patients (8/14, 57.1%). Persistent trigeminal artery (PTA) was confirmed in 6 cases, which the PSV decreased but RI increased in bilateral VA, meanwhile normal velocity was acquired in BA. After compressing the ipsilateral CCA, velocities of BA and bilateral PCA decreased significantly. There were 5 persistent hypoglossal artery (PHA) and 3 proatlantal intersegmental artery (PIA). Among these patients, CDFI displayed a tiny-lumen with reduced PSV and increased RI in bilateral VA. TCCS showed normal velocity in ipsilateral intracranial VA and BA, which were significantly reduced after compressing the ipsilateral CCA.

Conclusions:
PCVBA may cause the posterior circulation ischemia, especially in patients associated with ipsilateral ICA atherosclerotic lesions. The abnormal hemodynamic changes in different types of PCVBA could be evaluated by combination of CDFI and TCCS.
Abstract TP256: DWI Positive Cerebral Lesion is the Risk of Ischemic Stroke in Retinal Ischemic Patients
Authors: Iwanaga Takeshi , Okada Hiroshi , Inoue Takeshi , Yamashita Shinnji , Yagita Yoshiki
Published: January 2019

Background:
Retinal ischemia might be mainly caused by carotid stenosis and warning sign for ischemic stroke. Retinal ischemia is rare condition, therefore it is uncertain what lead to ischemic stroke in retinal-ischemic-patient.

Methods:
We retrospectively identified 128 patients who diagnosed retinal ischemia at 3 hospitals using each hospital stroke database collected from April 1st 2004 to Jun 30th 2016. We extracted data as patient sex, age, comorbidities and checked medical record for detecting recurrent of ischemic stroke and retinal ischemia. Logistic regression analysis was performed to analyze the effect of various factors on the recurrent of ischemic stroke.

Results:
The mean age of the patients at admission was 69 years old, and 93 patients (73%) was men. Seventy nine patients were diagnosed amaurosis fugax and 49 were retinal embolism. More than one visual defect attack had seen in 25 patients. One hundred twenty three patients were done cerebral MRI and DWI positive ischemic lesion was revealed in 12patients.Carotid stenosis were detected in 38 patients, patent foramen ovale were 40 patients, atrial fibrillation were 8 patients, complicated aortic plaque were 36 patients, and cancer were 25 patients. Mean follow-up period was 645 days and 6 patients had ischemic stroke, 4 had retinal ischemia and 18 underwent surgical intervention (carotid endarterectomy 12, carotid stenting 4, extracranial to intracranial bypass 2). Multivariable analysis found that the prevalence of ischemic stroke was significantly increased in DWI positive (odds ratio 10.9, confidence interval 1.7-69.6), under treatment cancer (10.0, 1.2-85.0), more than one visual attack (2.8, 1.1-7.3).

Conclusion:
DWI positive ischemic lesion on cerebral MRI was risk factor for ischemic stroke in retinal ischemic patients. We should consider to do MRI on retinal ischemic patients.
Abstract TP257: Comparison of Etiology of Central Retinal Artery Occlusions versus Branch Retinal Artery Occlusions
Authors: Miller Elan , Tzeng Diana , Natekar Aniket , Khalife Jane , Pancholy Maitri , Kumar Priyanka
Published: January 2019

Introduction:
Retinal artery occlusions (RAO) are a cerebral stroke equivalent and an ophthalmologic emergency that results in significant vision impairment. Etiology of branch retinal artery occlusions (BRAO) and central retinal artery occlusions (CRAO) varies widely in the literature, much of which comes from outside the United States. Furthermore, there is limited data comparing the etiologies of BRAO to CRAO. The Objective of this study is to compare BRAO to CRAO to determine if there is a difference in the etiology. Having a neuroscience hospital affiliated with a specialty ophthalmologic ER affords us a unique opportunity to conduct this research.

Methods:
Retrospective study looking at one year of data (April 2017 to April 2018), of patients admitted from our ophthalmologic ER to our acute stroke service with a diagnosis of RAO. A total of 86 patients met these criteria, 35 BRAO, and 51 CRAO. Etiology at discharge was recorded for each patient and the two groups were compared using odds ratio and Fisher's exact test.

Results:
Many of the patients were discharged without a clear etiology, 16 (45.7%) in the BRAO group and 26 (51.0%) in the CRAO group. Carotid/thromboembolic source was determined to be the etiology in six (17.1%) BRAO and four (7.8%) CRAO. Small vessel disease was responsible for 10 (28.6%) BRAO and 13 (25.5%) CRAO. "Other” etiology was found in three (8.6%) patients in the BRAO group, and one (2%) patient in the CRAO group. None of these etiologies had a statistically significant difference between the two groups. However, none of the patients with BRAO were found to have a cardioembolic etiology, as opposed to seven (13.7%) of the CRAO patients. This finding was statistically significant (odds ratio 0.084, P-value 0.038).

Conclusions:
In conclusion, the results of this study demonstrate that while there is much overlap in the etiology of BRAO and CRAO, and often the etiology remains cryptogenic, CRAO are statistically more likely to have a cardioembolic etiology than BRAO.
Abstract TP26: Benefit of Endovascular Therapy Across Clinical Trial Design and Technique: A Single Center Pooled Analysis
Authors: Jadhav Ashutosh P , Desai Shashvat , Jha Ruchira , Jovin Tudor
Published: January 2019

Introduction:
Endovascular therapy practice has evolved dramatically over the last decade. Various randomized trials have investigated the benefit of thrombectomy using different selection criteria including patient populations based on time of presentation, imaging criteria, and procedural technique. We sought to understand the benefit of thrombectomy in patients treated within the context of a clinical trial regardless of trial design at a single academic center.

Methods:
Data were analyzed from patients enrolled in randomized controlled trials investigating the benefit of endovascular thrombectomy over medical management (IMSIII, ESCAPE, SWIFT PRIME and DAWN) between 2007 and 2017 at a single academic referral center.

Results:
A total of 130 patients (intervention group, n=80; medical group, n=50) were identified across four clinical trials (IMSIII, n=46; ESCAPE, n=24; SWIFT PRIME, n=14; DAWN, n=46). There were no significant differences between the treatment arm and control arm in terms of age, gender, baseline NIHSS, baseline ASPECTS and occlusion location. There were no differences in rates of sICH, PH-2 or mortality. Rates of good outcome were superior in the intervention group with early neurological recovery (defined as NIHSS of 0-1 or drop in NIHSS of 8 points at 24 hours) at a higher rate of 53% vs 14% (p=<0.001) and higher rates of functional independence (90 day mRS 0-2 of 54% vs 26%, p=0.002). In multivariate logistic regression analysis, lower NIHSS and younger age were predictors of good outcome. There were comparable rates of good outcome irrespective of clinical trial, imaging selection criteria (CTP vs MRI), early versus late time window design (0-6 hours vs 6-24 hours) and procedural technique (Merci vs Solitaire/Trevo).

Conclusions:
At a large academic center, the benefit of endovascular therapy over medical therapy is observed irrespective of clinical trial design, patient selection or procedural technique.
Abstract TP260: Familial Brain Calcification and Truncating
PDGFB
Mutation: A Small Vessel Disease
Authors: Ilinca Andreea
Published: January 2019

Background:
Mutations in platelet-derived growth factor-B (PDGFB) have been associated with primary familial brain calcification, presenting with variable neurological and neuropsychiatric symptoms, and progressive peri-capillary calcifications. PDGFB mutations have also been linked to venous thromboembolism.

Methods:
We have examined a Swedish family with a novel mutation in PDGFB c.418C>T, p.Gln140* (Q140*). Clinical, hematological, radiological brain examinations and 123I-FP-CIT SPECT were performed. Systemic small vessel changes were analyzed by light and electron microscopy from skin biopsies. The effect of levodopa as symptomatic treatment was assessed.

Results:
Three family members in three successive generations carried the mutation and had significant brain calcifications (Fig. A). The index patient developed gait abnormalities in his 40s that improved on 200mg/d levodopa. Subsequently he developed throat-clearing tics and mild cognitive impairment. His mother, in her late 50s, had transitory ischemic attacks and, on MRI, bilateral confluent periventricular white matter hyperintensities of otherwise undetermined cause (Fig. C). She subsequently developed cognitive dysfunction. The index patient’s son has normal white matter on MRI and remains clinically unaffected in his early 40s. Skin biopsies showed generalised small vessel disease with progressive thickening of the arteriolar wall and hypertrophic endothelial cells that seem to almost entirely obliterate the lumen (Fig. B). Extensive characterisation of leucocyte markers showed no pronounced differences between 2 mutation carriers and 2 wild type relatives, but the index patient had had episodes of unexplained pulmonary embolism.

Conclusion:
The PDGFB Q140* mutation causes basal ganglia calcification, not directly correlated with clinical symptoms, and systemic vasculopathy with age-related cerebral white matter disease, associated with the clinical symptoms.
Abstract TP266: Patient and Bystanders Perceived Seriousness of Stroke Symptoms at Onset
Authors: Thomsen Rikke B , Iversen Ane Bull , Blauenfeldt Rolf , Andersen Grethe
Published: January 2019

Background:
Prehospital delay has several causes, most of them being patient-dependent. Knowledge of how patients and bystanders actually experience and react to symptoms at onset are essential.

Purpose:
Our aim is to characterize symptoms described by patients and bystanders at onset, perceived symptom seriousness, and whether this was associated with calling EMS directly.

Methods:
A cross-sectional study of consecutive acute stroke and TIA patients admitted at two stroke centres in the Central Denmark Region, in a three months period in 2018. Structured interviews of pre-stroke independent patients and bystanders were performed separately. Questions were open-ended. Symptoms identified as indicating stroke were classified as being focal or non-focal and perceived seriousness as mild or moderate/severe. Analysis were performed using logistic regression analysis.

Results:
A total of 1210 patients had a stroke/TIA in the period, of these 469 were included. We performed 654 interviews of patients and/or bystanders in median 1 day after stroke admission. Most frequent recognized symptoms by patients were limb palsy (31%), speech difficulties (26%) and dizziness (21 %). For bystanders: speech difficulties (47%), limb palsy (39%) and facial palsy (26%). Of patients and bystanders, 29 % and 23 % could not describe at least one focal symptom at onset. Focal symptoms were perceived as more serious in both patients and bystanders, OR (95% CI) 2.2 (1.29-3.76) and 2.61 (1.32-5.14). Patients who perceived symptoms as serious were more likely to make a direct EMS call, OR 2.10 (1.23-3.61). For bystanders, symptoms perceived as serious, were strongly associated with a direct EMS call: OR 22.7 (3.05-169.61). In patients being alone at stroke onset (98 (21%)) only 16% were able to call EMS directly and median (IQR) stroke severity (Scandinavian Stroke Scale) was lower among those calling EMS directly 57(52-58) vs 51(43-52), p<0.001.

Conclusion:
Approximately 1 in 3 patients did not recognize focal stroke symptoms, but when focal symptoms were recognized and perceived as serious, this was associated with direct EMS call. The role of a bystander is pivotal and bystanders role to
step in
of importance.
Abstract TP267: Performance of Components of the Canadian TIA Score to Predict Acute InfarctionAmong Patients Managed in an Emergency Department Observation Unit
Authors: Kwon Michelle H , Baird Janette , Madsen Tracy E , Godbout Edmond E , Yaghi Shadi , Saad Ali , Cutting Shawna M , Burton Tina M , Furie Karen L , Siket Matthew S
Published: January 2019

Introduction:
TIA risk stratification can help inform of impending stroke, but some scores lack sensitivity while others are impractical in the emergency department (ED) setting. The Canadian TIA Score has shown good discriminative ability at predicting early stroke recurrence and is designed to be applied in the ED, but awaits further validation.

Objective:
We assessed the performance components of the Canadian TIA Score in predicting diffusion weighted MRI (DWI) abnormalities and 30-day adverse events in a cohort of clinically suspected TIAs placed in an ED observation unit (OU).

Methods:
Patients in a large, urban, academic ED with suspected TIA deemed appropriate for the OU from 4/2013-7/2018 were included. Rates of acute infarct on DWI and adverse 30-day events were assessed. Logistic regression was performed to determine the odds of DWI-confirmed stroke from 12 of the 13 items on the weighted Canadian TIA Score (we did not collect platelet count); and for poor versus good health outcomes at 30-days. The AUC with 95% CIs were also calculated for significant models, and the The Youden index (J statistic) was determined to assess maximum effectiveness of diagnostic test across a range of cut-points.

Results:
Of 1208 patients admitted over the time period, 1097 had DWI performed (90.1%). Clinical features are described in
Table 1
. The logistic regression model for the Canadian TIA Score predicting acute stroke on DWI was significant (Wald χ2 (1) = 36.6, p < 0.001), with an odds ratio of 1.27 (95%CI: 1.16, 1.33), and AUC = 0.65 (95%CI: 0.61, 0.69). In predicting acute stroke, the maximum J value = 0.20; Canadian rule score ≥ 4; sensitivity = 0.68, specificity = 0.52. Of 593 patients reached at 30-days, 510 (86%) reported no adverse events. Of the 83 who did not, 1 had a disabling stroke and 1 had died.

Discussion:
In this overall low-risk cohort of ED patients with suspected TIA managed in an OU, the Canadian TIA Score performed reasonably well at predicting acute DWI abnormalities.