bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP343: Low Density Sign in Intracerebral Hemorrhage: A Novel Predictor for Hematoma Expansion
Authors: Chu Heling , Tang Yuping , Huang Chuyi , Dong Qiang
Published: October 2018

Background:
Hematoma expansion in intracerebral haemorrhage (ICH) patients is a major determinant of early deterioration and associated with poor outcomes. Early identification of hematoma expansion with noncontrast computed tomography (NCCT) is very beneficial. We newly identified a NCCT sign called low density sign. Our study was to investigate whether low density sign was applicable for hematoma expansion prediction.

Methods:
Patients with spontaneous ICH enrolled in Huashan Hospital, Fudan University who underwent baseline NCCT scan within 6 h after ICH onset and the follow-up NCCT scan within 24 h after initial CT scan were included. Hematoma expansion was defined as absolute growth greater than 6 mL or a relative growth of more than 33%. The low density sign was defined as: (1) The hypoattenuation area that easily recognized by the naked eye has an identifiable border and most of the area within the hematoma. (2) The hypoattenuation area may vary in shape and connect or not with the adjacent brain tissue. (3) The minimal density the hypoattenuation area should be ≤27 Hounsfeld units (HU). For investigating the relationship between the presence of low density sign and hematoma expansion, univariate and multivariable logistic regression analyses were performed.

Results:
A total of 236 patients were included in the current study, 26.7% of which were observed hematoma expansion. Low density sign was found in 49 (20.8%) of the study population which was more common in patients with hematoma expansion (58.7%) than those without hematoma expansion (6.9%, P<0.001). Univariate and multivariable logistic regression analyses revealed Low density sign was an independent predictor for hematoma expansion (P=0.01, 95% CI: 3.25-114.05). The sensitivity, specificity and accuracy of low density sign for predicting hematoma expansion were 58.7%, 93.1% and 83.9% respectively, which were higher than previously reported NCCT signs: blend sign and black hole sign except the specificity of black hole sign (P<0.05).

Conclusion:
Our findings indicate low density sign as an easily identified NCCT sign may be an appropriate candidate for predicting hematoma expansion in patients with ICH.
Abstract TP355: Rapid Cycle Implementation of a Standard Stroke Neurological Check Before Comprehensive Stroke Re-certification Survey
Authors: Cox Kailey , Clark Diane
Published: October 2018

Background:
Components of ongoing stroke neurological assessment are remarkably controversial. Gap analysis preceding a Joint Commission (TJC) Comprehensive Stroke Re-Certification (CSC) survey identified organizational deficiency in defining a neurological check that trends neurological status of stroke patients. A standard stroke neuro check was implemented 30 days prior to the CSC survey. During the CSC survey, closed chart review performed on a patient hospitalized prior to the implementation revealed lack of trending patient’s original symptoms. Real time patient tracers also revealed lack of consistency of assessment between healthcare providers, missing documentation of notification to providers for a status change, missing groin checks and pulse checks. These issues resulted in a Requirement for Improvement (RFI) from TJC.

Purpose:
Determine if the rapid cycle implementation of standard neuro check one month prior to CSC survey was successful, and if other documentation requirements as defined by TJC were completed for the 30 day period prior to CSC Survey.

Methods:
Charts from 30 days prior to the survey between May 6 and June 6, 2016, were audited for compliance with standard neuro checks, groin checks, pulse checks, NIHSS agreement between healthcare providers, and status change provider notification. All ischemic stroke patients treated with IV alteplase and/or mechanical thrombectomy, Subarachnoid Hemorrhage, Craniotomy, Coiling, Clipping, Carotid Endarterectomy were included (n=30). Frequency of needed assessments varied based on stroke type and treatment.

Results:
A total of 30 cases revealed 89.7% overall compliance with all required documentation elements. Of 11 ischemic stroke treatment patients there were 1077 opportunities for neuro checks with 907 (84%) of those opportunities completed. Compliance with all remaining components were: NIHSS agreement between providers 92%; status change resulting in notification 96%; and vital signs 96%.

Conclusions:
Rapid cycle implementation of a standard neuro check was feasible in a large CSC, well received by staff and satisfied the requirements for TJC CSC 10 day clarification process in 2016. Implementation of a standard stroke neuro check needs further research.
Abstract TP371: Use of a Rapid Activation Algorithm for Endovascular Intervention Treatment of Stroke
Authors: Glidden Michele , Sercer Helen
Published: October 2018

Background and Purpose:
A growing body of evidence has demonstrated that timely intervention for patients experiencing stroke can prevent loss of functioning brain tissue. When the stroke is caused by a large vessel occlusion (LVO), the goal is prompt endovascular intra arterial treatment in the angio suite. The challenge at our organization was to develop a method to coordinate the necessary resources consistently and quickly to achieve this. The purpose of this presentation is to share our experience of developing an algorithm for rapid activation of the neurointerventional lab for patients who are candidates for recanalization of an acute LVO.

Methods:
Using current endovascular treatment guidelines, a multidisciplinary team developed a rapid activation process to mobilize the necessary individuals and resources to support prompt endovascular treatment in the neurointerventional lab. After identifying key stakeholders, the team defined the process, developed performance metrics, and drafted education and communication plans to operationalize the initiative. The team met biweekly for six months in 2016 and completed three months post go live in January 2017. The activation process went live on September 29, 2016. Embedded data points were used to measure performance.

Results:
Using a rapid activation process demonstrated timelier door to lab times for acute stroke patients who were candidates for endovascular intervention. Average “door to lab time” before go live was 218 minutes. Average “door to lab time” after go live was 138 minutes. Average “door to recanalization time” was 456 minutes before go live and “door to recanalization time” after go live was 238 minutes. (N=5 before go live; N=9 after go live).

Conclusion:
The implementation of a rapid activation process demonstrated shorter door to lab table and subsequent recanalization times for patients experiencing a LVO stroke who went to the lab for revascularization. These results are encouraging. However continued improvement is needed in order to further decrease recanalization times that may result in better clinical outcomes.
Abstract TP374: EMS Simulation: Engaging Medics through Stroke Simulation
Authors: Barnard Amy L , Somberg Christine
Published: October 2018

Background:
Advanced Practice Nurses from a community hospital provided education using a realistic stroke simulation scenario to local Emergency Medical Service (EMS) providers. EMS pre-hospital notification is one of the Target: Stroke best practice strategies. Rapid and accurate recognition of stroke in the pre-hospital setting is a key component of ensuring a stroke patient receives efficient and timely care.

Purpose:
To increase pre-hospital paramedic’s confidence in accurately identifying possible stroke patients using a simulation scenario.

Methods:
This was a program evaluation project. A stroke simulation scenario developed from an actual case was used to engage the paramedics in a realistic stroke scenario they could encounter in the pre-hospital setting. A standardized patient was used in the simulation scenario. A care confidence scale was used pre-simulation and post-simulation to evaluate each participant’s confidence in identifying stroke signs and symptoms, identifying the patient’s last known normal time, and performing the Cincinnati Prehospital Stroke Scale. An overall simulation evaluation was also completed by participants. Fifteen paramedics participated in the simulations.

Results:
There was increase in confidence in two out of the three measures. There was an overall 4.54% increase in the confidence of appropriately identifying stroke signs and symptoms. There was an overall 4.76% increase in the confidence in identifying the patient’s last known normal from pre-simulation to post-simulation. There was no difference in the confidence of assessing a patient using the Cincinnati Prehospital Stroke Scale. 15 simulation evaluations were completed. Each participant strongly agreed simulation was a valuable way to practice EMS skills and teamwork. Participants also strongly agreed they would like to see more simulation offerings in the future.

Conclusions:
Simulation is an effective intervention to increase paramedic’s confidence in identifying stroke signs and symptoms, and the patient’s last known normal time.
Abstract TP376: Disparities in Outcomes among Inpatient Stroke in Women Associated with Rural-Urban Insurance Status in China
Authors: Rao Zhenzhen , Gu Hongqiu , Li Zixiao , Wang Yilong , Wang Yongjun
Published: October 2018

Background:
The annual incidence of stroke in China has increased more drastically in women; moreover, women who experience stroke are less likely to recover. Despite a few studies that have demonstrated gender differences in stroke care and outcomes, there has been limited research exploring insurance-related disparities in outcomes, particularly among female stroke patients. We examined the relationship between rural/urban insurance status on the 1-year clinical outcomes of stroke in women.

Method:
Cox proportional hazard model was employed to analysis the clinical outcome endpoints in our model. The logistic regression model was used to select significant risk factors. The generalized estimating equation model was applied to control the cluster effect of hospitals in order to obtain a more precise estimation.

Results:
Compared with women covered by the Urban Resident/Employee Basic Medical Insurance (URBMI/UEBMI), those covered by the New Rural Cooperative Medical Scheme (NRCMS) were younger, less likely to have vascular risk factors and stroke awareness or undergone treatment for hypertension and dyslipidemia, and more likely to have received early antithrombotics, antithrombotics at discharge, and lipid-lowering drugs (Table 1). One-year stroke recurrence and mortality was significantly higher in women covered by the NRCMS (Table 2). Significant differences in age, stroke risk factors, awareness and treatment, care process, and 1-year stroke recurrence and mortality were observed.

Conclusion:
Healthcare policymakers need to focus their attention on these disparities and take suitable steps to improve primary healthcare service in rural areas.
Abstract TP379: Stroke Survivors Achieve Good Blood Pressure Control with Nurse Practitioner Led Self-Blood Pressure Monitoring Program Following AHA Guidelines
Authors: Andrusin Jeanne , Breen Joan , Garth Hannah
Published: October 2018

Background:
Hypertension is a leading risk factor for stroke affecting 33% of adults in the US with only 54% adequately controlled. National guidelines recommend blood pressure (BP) self-management at home; however the partnership with clinicians is necessary for education and coaching. BP self-monitoring in stroke survivors has not been widely reported. The purpose of this quality improvement project was to increase the provision of BP education and support stroke patients receiving outpatient rehabilitation services with BP self-management.

Methods:
Stroke patients treated in a community based multidisciplinary outpatient stroke rehabilitation program addressing medical, rehabilitation, psychosocial and vocational needs between 6/2016 - 3/2017 were included. Patients met with a Nurse Practitioner (NP) to receive a standardized educational program based on the American Heart Association’s Life’s Simple 7 addressing cardiovascular education, independence with medications and health maintenance. Additional training was provided during the first 3 NP visits related to the BP guidelines and self-measurement with a single wrist monitor. Manual and machine BPs measured by the NP were correlated with self BPs measured by each patient. Patients recorded their self BPs at a designated station prior to individual physical therapy sessions. The first 20 patients received pre- and post-assessment of BP knowledge and confidence to self-monitor.

Results:
Among 29 consecutive stroke patients (59% male; 14% hemorrhagic; 83% hypertensive) 100% performed self BP monitoring and recording. A total of 571 self BPs were recorded with an average of 20 per patient (range=2-77). Four patients with BPs <120/80mmHg self-monitored an average of 2.5 times/week; 22 patients with BPs 120/80-139/89mmHg self-monitored 1.4 times/week; and 3 patients with BPs 140/90-160/90mmHg self-monitored an average of 1.2 times/week (none >160/90 mmHg). Knowledge of AHA BP guidelines improved 90% and confidence to self-monitor improved 65%. 50% began to self-monitor at home.

Conclusions:
Community dwelling stroke survivors can perform BP self-monitoring with good BP control, improved knowledge of AHA guidelines with increased confidence and successful carry over to home.
Abstract TP393: Treatment Strategies in Stroke Recurrence Related to Complex Atheromatous Aortic Plaques Embolism
Authors: Juega Jesus M , Jorge Pagola , David Rodriguez-Luna , Noelia Rodriguez-Villatoro , Ana Aires , Boned Sandra , Requena Manuel , Rubiera Marta , Muchada Marian , SanJuan Stela , Parra Carmen , Ribo Marc , Tomasello Alejandro , Garcia Alujas Teresa , Evangelista Arturo , Alvarez Sabin Jose , Molina Carlos
Published: October 2018

Background:
Complex atheromatous aortic plaques (CAAP) are a source of embolism stroke but is not clear established the best secondary prevention treatment yet.

Objective:
we aimed to analyze recurrence of stroke in ESUS patients based on different prevention treatment strategies regarding characteristics of atheromatosis aortic plaques .

Methods:
From January 2012 to July 2017, CAAP screening in acute phase of stroke in ESUS patients was realized (we excluded main cardioembolic sources and intracranial or extracranial symptomatic stenosis >50%). We performed CTA from proximal to distal aortic arch. CAAP was defined as a plaque > 4 mm thickness or with irregular ulcerations > 2 mm depth. Baseline characteristics and neuroimaging patterns were recorded. In patients that was possible to perform a transesophageal echocardiography (TTE) in subacute phase we assessed the size of endoluminal plaques, presence of ulcerated plaques and mobile components or thrombus .Follow up with analysis of recurrence in this cohort was done.

Results:
157 patients were screened. CAAP detection by CTA was 57% (88/157). CAAP was associated with older age (73± 9 vs. 66±14 years, p=0.005), hypertension (76.6% vs. 59.4%, p=0.027), diabetes (34.1% vs. 18.8%, p=0.037), and a trend towards stroke recurrence (19.5% vs. 9.4%, p=0.086). TEE was performed in 73 patients: recurrence of stroke (n=9) (12%) was associated with bigger endoluminal plaques (6.7±3.5 vs. 4.8±2.6 mm, p<0.001), ulcerated plaques (26.9% vs 4.3%, p=0.005), and with presence of thrombus or mobile components (26.3 % vs. 5.7 %, p=0.014). All patients with presence of mobile thrombus in TEE (n=19) received oral anticoagulation (OAC); in 16 patients ( 85%) , OAC was withdrawn after 3 months with control TEE that confirmed disappear of mobile parts and antiagregation was initiated with recurrence in 5/ 19 patients associated with active smoking (60.0% vs. 7.1%, p =0.013 ).

Conclusions:
Complex atheromatous aortic plaques are relevant stroke sources of embolism. Size, ulcerated plaques and mobile components were associated with stroke recurrence. A subgroup of patients may benefit of chronic oral anticoagulation in order to avoid stroke recurrence.
Abstract TP398: Hemodynamic Predictors of Early Neurological Worsening in Acute Ischemic Stroke
Authors: Miller Joseph , Tsuei Jessica , Calo Sean , Levy Phillip , Lewandowski Christopher
Published: October 2018

Introduction:
Early neurological worsening is common in acute ischemic stroke (AIS) and associated with increased morbidity.

Hypothesis:
We tested the hypothesis that early hemodynamic factors are associated with early neurological worsening in AIS.

Methods:
Prospective, observational study of AIS patients with a NIHSS > 3. Patients were enrolled in the emergency department as soon as AIS was suspected. Exclusion criteria were: time of onset > 12 hours and hemorrhagic stroke. We performed baseline non-invasive, continuous hemodynamic monitoring and measured cerebral blood flow velocity with transcranial Doppler insonation of the middle cerebral arteries. We limited analysis to patients with confirmed stroke. Early neurological worsening was defined by any increase in the NIHSS over the first 24 hours.

Results:
We enrolled 77 patients, 57 of whom had AIS confirmed on imaging. The mean age was 67 ± 13 years, 53% were female and 78% were African American. The median NIHSS was 6 (IQR 4,8) and baseline SBP was 151 ± 35 mmHg. Fifteen (26%) patients had neurological worsening. Blood pressure, age, and presenting NIHSS were not predictive of neurological worsening. Low stroke volume index was associated with neurological worsening (OR 5.2, 95% CI 1.5 - 18.3). There was no significant difference in baseline MCA mean flow velocity (MFV) between patients with or without neurological worsening (42 vs 41 cm/sec, p=0.8). There was a trend towards higher MFV in patients with normal stroke volume vs. those with low stroke volume (43 ± 14 vs 37 ± 9 cm/sec, p=0.07).

Conclusion:
In this sample of low to moderate severity AIS patients, low stroke volume index was predictive of early neurological worsening, suggesting a hemodynamic effect on the ischemic penumbra.
Abstract TP400: Acute Catecholamine Surge Reflects the Prognosis in Patients With Aneurysmal Subarachnoid Hemorrhage
Authors: Uramaru Koichi , Kikkawa Yuichiro , Ogura Takeshi , Kamide Tomoya , Suzuki Kaima , Otsuka Munehiro , Takeda Ririko , Tsuchiya Ryosuke , Shibata Aoto , Kurita Hiroki
Published: October 2018

Objective:
We investigated that the characteristics of serum catecholamine concentration at the hyper-acute phase of aneurysmal subarachnoid hemorrhage (SAH) and its relationship between patient outcome and delayed vasospasm.

Methods:
Patients with aneurysmal SAH (n=170) were prospectively enrolled between 2008 and 2011. Baseline demographic data and physiological parameters, including plasma concentrations of adrenaline (AD), noradrenaline (NA) and dopamine (DP) were evaluated.

Results:
On admission, plasma AD, NA and DP levels were significantly higher in patients with a poor clinical grade on admission (Hunt and Kosnik: IV-V), compared to those with a good clinical grade on admission (Hunt and Kosnik: I-III). AD showed a significantly high concentration immediately after the onset of SAH and then rapidly decreased. The levels of NA peaked within 6 hours after onset, then significantly decreased. The time course of the elevation of DP showed a similar trend to that of NA. The each catecholamine levels significantly correlated with each other. Multivariate analyses demonstrated age, poor clinical grade, plasma AD and NA levels were predictors of poor patient outcome. Poor clinical grade, Fisher scale and plasma AD level were predictors of the development of delayed vasospasm.

Conclusion:
The present study suggests that sympathetic activation in patients in the acute phase of SAH reflects the severity of SAH, and is closely related to the development of delayed vasospasm, leading to the subsequent immune response and inflammatory reactions. Suppressing catecholamine surge in hyper-acute phase may contribute to prevention of vasospasm and improvement of patient outcome.
Abstract TP403: Effect of Hypercapnia on Dynamic Cerebral Autoregulation During Transient Hypotension
Authors: Singh Vinit , Kumar Shivangi , Prakash Kiran , Jaryal Ashok , Deepak K K
Published: October 2018

Background and Purpose:
Hypercapnia leads to increased cerebral blood flow and impaired autoregulation by changing the cerebrovascular resistance (CVR). We studied the effect of hypercapnia on critical closing pressure (CCP) and resistance area product (RAP) which effectively reflects the role of vascular tone and resistance respectively in altering cerebrovascular resistance and maintaining cerebral autoregulation during transient hypotension.

Methods:
–26 healthy subjects had continuous cerebral blood flow velocity and arterial blood pressure recording. Transient hypotension was induced by sudden release of thigh cuff after suprasystolic inflation for 3 minutes. 3 trials of thigh cuff maneuver were performed with normal breathing, 3% CO
2
breathing and 5% CO
2
breathing. CO
2
inhalation was given for last 45 seconds of thigh cuff maneuver and continued for 90 seconds after release. Autoregulatory Index (ARI) was calculated for each trial with Tieck’s model. CCP and RAP were computed for 10 seconds’ window each at 1 minute after inflation (Baseline), immediately before release (Prerelease) and immediately after release (Release) of inflated thigh cuff.

Results:
–ARI values decreased significantly (p < 0.0001) from 5.46 ± 1.47 to 2.0 ± 1.35 and 1.63 ± 1.09 during 3% CO
2
and 5% CO
2
trial respectively. No significant changes were observed in CCP value during thigh cuff release with all three trials. RAP significantly dropped from prerelease value after thigh cuff release in all 3 trials. Drop in RAP attenuated during hypercapnia trial and had significant (p < 0.0001) difference between RAP
Prerelease – Release
(
d
RAP) for Normal breathing (0.20 ± 0.12) and 3% and 5 % CO
2
trials (0.089 ± 0.090, 0.081 ± 0.093).
d
RAP was significantly correlated (Spearmen r = 0.42, p = 0.0004) with the ARI values where higher
d
RAP had better autoregulation.

Conclusion:
– Cerebral autoregulation during transient hypotension acts by changing vascular resistance i.e. RAP without any effect on vascular tone i.e. CCP and had been suggested to reflect myogenic component of autoregulation to blood pressure changes. We concluded that hypercapnia leads to impairment of myogenic component of autoregulation during transient arterial blood pressure changes as suggested by attenuated
d
RAP.
Abstract TP420: Variability in Functional Outcome Measures Used in Contemporary Animal Models of Stroke and Vascular Cognitive Impairment
Authors: Hietamies Tuuli M , Ostrowski Caroline , Zhong Pei , Feng Luyang , Work Lorraine M , Quinn Terence J
Published: October 2018

Functional measures are recommended as primary outcome within clinical stroke trials but there is substantial heterogeneity in the assessments used. There may be a similar lack of consistency to outcome assessment in preclinical studies. Our aim was to collate studies using animal models of stroke and vascular cognitive impairment (VCI) and describe the functional assessment measures used.

A focused literature search was conducted across 14 chosen journals. Inclusion was limited to original articles describing preclinical research in stroke or VCI, published between January 2005 and December 2015 inclusive. Complete articles were reviewed for functional assessments used in each trial. Primary analyses were numbers of functional tests used; frequency of use of each test and temporal trends.

Of 91,956 stroke articles screened, 1,303 studies were analyzed, of these 609 did not report any functional measures and 56 had no access to full article, giving 638 articles for final analysis. For VCI, 56 papers were assessed in full, of these 16 reported no functional measures, giving 37 papers for final analysis.

In stroke trials, 559 (89%) used an ischemic and 94 (14%) a hemorrhagic model. In VCI studies, 11 different models were found, with global hypoperfusion being the most common, applied in 11 (30%) articles. Of studies analyzed, the median number of tests applied per trial was 1 in both cases with only 9% of stroke trials and 16% of VCI trials reporting functional measures as primary end points. There were 74 different assessments described in stroke trials, consisting of functional tasks and neurological deficit scores (NDS). Rotarod was the most frequent assessment (15% of trials), and Bederson’s the most frequently used NDS (39% of trials). In VCI studies, there were 19 different assessments employed, with Morris Water Maze (MWM) being most popular (56% of studies). Marked inconsistencies were found in physical and functional characteristics of all assessments reported.

There is heterogeneity amongst and lack of prioritizing the use of outcome measures in pre-clinical trials. These inconsistencies compromise comparison and meta-analysis. Thus, a consensus of core-set functional outcome assessments could improve consistency in animal stroke and VCI models.
Abstract TP424: Automated Detection of Lacunes in a Cohort of Patients Presenting With Transient Ischemic Attack or Acute Ischemic Stroke
Authors: Hannawi Yousef , Latif Omar , Senaras Caglar , Tariq Areej , Torbey Michel T , Gurcan Metin N
Published: October 2018

Introduction:
Cerebral Small Vessel Disease (CSVD) impacts the functional outcome of acute ischemic stroke (AIS) patients. The majority of the available tools to quantify its burden relies on visual categorical scales, which is labor intensive and subject to inter- and intra-reader variability. Fully automated tools are rare and mostly focus on white matter hyperintensity (WMH) as a surrogate for CSVD. We aimed to develop a novel software that simulates the clinicians’ rational to detect lacunes on clinical MRI scans of patients presenting with acute AIS or transient ischemic attack (TIA).

Methods:
Patients presenting with symptoms of acute AIS or TIA were prospectively recruited. Lacunes were scored on the first brain MRI collected within 24 hours of hospital admission by a board-certified neuro-intensivist/vascular neurologist according to the Neuroimaging Standards for Research into Small Vessel Disease (STRIVE) criteria. Following standard skull stripping and co-registration, automated software was developed in Matlab by calculating maximal intensity difference of co-registered voxels on FLAIR and T2 MRI sequences. Cerebrospinal fluid was removed by seed-based growing approach and lacunes were subsequently detected based on their size (3-15 mm) and morphological features.

Results:
30 subjects were included (age 61.6±16.1, 30% females); 6 of which had TIA and 23 had AIS (10 acute lacunar stroke, 3 cardioembolic, 10 cryptogenic and 1 stroke of other determined etiology). There were 24 lacunes detected in 12 subjects by the human reader. The automated system accurately identified subjects with lacunes in 91.6% of the cases with 75% specificity. Negative predictive value for subjects without lacunes was 93.7%. At the lesion level, the paradigm identified 62.5% of all lacunes in all subjects with positive predictive value of 78.9%; 67.0% of the missed lacunes were in close proximity to the ventricles.

Conclusions:
Automated identification of lacunes is feasible on clinical MRI scans of patients with acute AIS or TIA. Lacunes closer to the ventricles are challenging and may require a separate approach.
Abstract TP46: The Probability of an Endovascular Intervention Target Independent of Time From Last Known Well
Authors: King Ben , Dula Adrienne N , Luby Marie , Latour Lawrence , Warach Steven
Published: October 2018

Introduction:
Selection of patients based on treatment-related targets has been especially important for endovascular therapy. Recently presented trial evidence has demonstrated that cases with an eligible arterial occlusion and a target PWI-DWI mismatch were able to successfully receive treatment beyond the 6 hour window.

Method:
The LESION Study is a prospective cohort study of the baseline MR imaging (<24 hrs from onset and prior to treatment) of 1,092 consecutive ischemic stroke presentations with admission NIHSS ≥4. Multiple therapeutic targets were assessed. Endovascular intervention target was defined as the presence of ischemia on MRA in the ICA or MCA-M1 arterial branches. Presence of PWI-DWI mismatch was qualitatively determined by vascular neurologists. Multivariate logistic regression was used to test for association of time from onset with presence of an endovascular target, while examining the roles of presentation and imaging characteristics.

Results:
Probability of an endovascular target decreases over the first 24 hours (OR=0.96; p=0.004). However, stratification or adjustment for a PWI-DWI mismatch signal and/or admission NIHSS confounds the effect of occlusion target over time. Stratification by mismatch demonstrates a consistently higher proportion of endovascular target presence in those with a concurrent target mismatch. For cases with a target mismatch, presentation within the 6 hour window is associated with just a 17% greater likelihood of endovascular target relative to those beyond 6 hours (OR=1.17; p > 0.05). In multivariate modeling: NIHSS, mismatch, and sex were all identified as independent risk factors for presence of an endovascular target (all p < 0.01), while time was not significantly associated with target presence.

Discussion:
While the presence of an arterial occlusion in territories relevant to endovascular intervention appear to be related to time from onset, stratified and adjusted analyses show that this relationship is not maintained when limited to cases with and without a target mismatch identified. This finding has clinical and methodological implications for selection of patients for intervention at varying time intervals.
Abstract TP5: Mr Predicts a Reliable and Useful Tool in Identifying Benefit of Mechanical Thrombectomy in Patients With Large Vessel Occlusion
Authors: Majidi Shahram , Leon Guerrero Christopher R , Olan Wayne J , Sigounas Dimitri , Memon Muhammad Z , Burger Kathleen M , Chun Albert , Sarin Shawn
Published: October 2018

Background:
The AHA/ASA guideline recommends endovascular therapy for patients with acute ischemic stroke within 6 hours from symptom onset. Identification of the patients most likely to benefit (and those most likely to be harmed) from reperfusion plays a pivotal role in decision-making. We applied the MR PREDICTS tool (clinical decision making tool derived from MR CLEAN clinical trial) on a real-world sample of patients with acute ischemic stroke to assess its utility in predicting clinical benefit from endovascular therapy.

Methods:
We identified all patients with acute ischemic stroke with occlusion of the distal internal carotid artery, proximal M1, or M2 segment of the middle cerebral artery who underwent endovascular reperfusion procedure (thrombectomy and/or intra-arterial thrombolysis) from July 2016 to June 2017. Patients were divided into two groups; those with a good outcome (90 Day mRS 0-2) and those with a poor outcome (90 Day mRS 3-6). The MR PREDICTS tool was used to determine absolute treatment benefit for each patient. This predicted outcome was compared to actual patient outcome.

Results:
A total of 22 patients were identified. Eight patients had a good outcome and 14 patients had a poor outcome. The calculated absolute treatment benefit from endovascular therapy using the MR PREDICTS tool was consistently higher among patients in the good outcome group, with an average absolute treatment benefit of 12% greater among these patients compared to those in the poor outcome cohort (19% versus 7%). Of note, patients with a poor outcome had a higher rate of prior stroke, higher baseline NIHSS, longer symptom onset to groin puncture time, less favorable collaterals and lower rate of successful recanalization defined as TICI 2b or 3 (100% versus 64%).

Conclusion:
There is a strong correlation between predicted treatment benefit by MR PREDICTS tool and actual patient outcomes which supports broader use of this tool during the decision-making process for endovascular therapy in patients with acute ischemic stroke.
Abstract TP54: Machine-Learned Characterization of Acute Ischemic Stroke Clots Reveals a Correlation Between Clot Composition and Density on CT
Authors: Fitzgerald Seán , Wang Shunli , Dai Daying , Murphree Dennis H , Pandit Abhay , Douglas Andrew , Kadirvel Ramanathan , Brinjikji Waleed , Kallmes David F , Karen Doyle M
Published: October 2018

Introduction:
The composition of acute ischemic stroke (AIS) blood clots can impact their successful removal via endovascular therapy. Identification of the clot composition prior to endovascular treatment may influence the optimal treatment strategy. In this study, we aimed to investigate the relationship between the Hounsfield Unit intensity on CT and machine-learned characterization of clot composition.

Methods:
Prior to endovascular treatment, each patient had a non-contrast CT performed. Histopathological analysis of the clots was performed and clot composition was quantified via standard thresholding techniques using Adobe Photoshop. In addition, following representative cell labeling by an expert pathologist, image segmentation algorithms (Orbital Image Analysis, Actelion Ltd.) were trained on each case to quantify composition by cell type. The clots were categorized into 3 groups: red blood cell (RBC) dominant (>50%), RBC proportion equal to fibrin and fibrin dominant (>50%). Correlations between clot composition and Hounsfield Units (HU) density on CT were assessed. A positive Hyperdense Artery Sign was defined as ≥50 HU.

Results:
Twenty patients were included in the study. There was a significant correlation between clots quantified using Adobe Photoshop Image-Pro and Orbit image analysis (
ρ
= 0.837,
p
< 0.001). A significant relationship was found between clot composition and the presence of a HAS sign, (

X
2

(2) = 6.496,
p
= 0.039). There is a significant positive correlation between percentage of RBC in the clot and the presence of a HAS sign (
ρ
= 0.632,
p
= 0.002**). There is also a significant positive correlation between the presence of fibrin-rich and the absence of a HAS sign (
ρ
= 0.600,
p
= 0.004**).

Conclusion:
Machine learning software can accurately quantify AIS clot composition. The Hounsfield unit density of an AIS clot on a non-contrast CT correlates with the composition of the clot. Measuring the HU of the clot on CT prior to endovascular intervention may inform the clinician of the clot type and help to determine the most appropriate treatment strategy for that clot.
Abstract TP59: The Sustained DeyeCOM Sign as a Predictor of Large Vessel Occlusion
Authors: Attenhofer Kevin S , Selvan Pradeep , Lunagariya Abhishek , Rapp Karen , Hailey Lovella , Mortin Melissa , Agrawal Kunal , Modir Royya , Huisa Branko , Meyer Dawn , Hemmen Thomas , Meyer Brett
Published: October 2018

Introduction:
Rapid imaging in acute stroke is critical and often occurs before full examination. Early, reliable exam findings clarify diagnosis and improve treatment times. Suspected stroke patients typically undergo both acute non-contrast CT and CT Angiogram (CTA). The DeyeCOM sign (conjugate gaze deviation on CT) has been described as a predictor of ischemic stroke with good specificity. In this study, we further evaluate a sustained DeyeCOM sign on both CT and CTA in early prediction of anterior large vessel occlusion (LVO).

Methods:
We retrospectively reviewed 46 acute stroke code patients between April and June 2017 from the prospective, IRB approved UCSD Stroke Registry. Patients had both CT and CTA as part of their acute stroke work-up as standard of care. DeyeCOM(+) sign was defined as a conjugate gaze deviation on CT or CTA of at least 15 degrees measured by caliper technique on Agfa IMPAX software (v.6.6.1.3525). DeyeCOM(++) was defined as sustained gaze deviation on both CT and CTA.

Results:
Three groups of patients were observed: 1) gaze deviation on both CT and CTA (DeyeCOM(++)), 2) non-sustained gaze deviation (+ on CT or CTA but not both), and 3) no gaze deviation (DeyeCOM(--)). All patients with DeyeCOM(++) (8/8, 100%) had anterior LVO. Of those with non-sustained gaze deviation, 2/7 (29%) had LVO. No DeyeCOM(--) patients (0/31, 100%) had LVO. Of the DeyeCOM(--) patients, 16/31 (52%) were stroke mimics and 15/31 (48%) had strokes that were not LVO. The specificity and sensitivity of DeyeCOM(++) for LVO was 100% (CI .90-1.0) and 80% (CI .44-.97). The specificity and sensitivity of DeyeCOM(--) for absence of LVO was 100% (CI .69-.10) and 86% (CI .70-.95).

Conclusion:
In this study, DeyeCOM(++) had 100% specificity for anterior LVO while DeyeCOM(--) had a 100% specificity for absence of LVO. DeyeCOM(++) false positive rates were low. Sustained DeyeCOM, whether positive or negative, is a strong predictor of ultimate diagnosis. These results should support practitioners’ confidence that DeyeCOM(++) reflects LVO stroke and is unlikely to be a mimic and DeyeCOM(--) patients likely do not have LVO. This data point can potentially lead to quicker endovascular treatment times. Further comparisons in this dataset are ongoing and work in a larger data set is needed.
Abstract TP64: Visual Perception, Cognition, and Non-Contrast CT Aspects
Authors: Wilson Alexis T , Dey Sadanand , Evans James , Tham Carol , Assis Zarina , Teleg Ericka , Pordeli Pooneh , Eswaradass Prasanna , van Gaal Stephen , Najm Mohamed , Neweduk Anneliese , Horn MacKenzie , Kuang Hulin , Hafeez Moiz , Qiu Wu , Demchuk Andrew , Goyal Mayank , Hill Michael D , Menon Bijoy
Published: October 2018

Introduction:
As image interpretation is a visual perception task, it is affected by context and task structure. The non-contrast CT Alberta Stroke Program Early CT Score (ASPECTS) is considered an objective radiologic measure of the extent of ischemic change in cases of acute ischemic stroke. We hypothesize that variability in ASPECTS reading is because readers are susceptible to interplay between higher-order, top-down information (clinical background or other imaging) and bottom-up sensory information, and that experts are more resistant to being swayed by these factors than novices.

Methods:
We tested the effect of three top-down background-information conditions (no information; clinical information with affected side; clinical information plus CT angiography (CTA)) and three environment/task conditions (daylight, core lab, time pressure) on the inter-rater reliability (IRR) of NCCT ASPECTS. Three raters (trainee, fellow, neuro-radiologist) independently scored 150 NCCT scans from acute ischemic stroke patients, with 50 allocated to each environmental task. This was repeated over three sessions, with one for each background-information condition. ASPECTS on CT perfusion Tmax thresholded scans served as ground truth.

Results:
IRR improved when clinical information and CTA were provided (ICC 0.55 - clinical + CTA, 0.41 - clinical, 0.10 - no information). In some situations (NIHSS <5, onset-to-imaging times >180 min), IRR was greater with clinical information but without CTA. Daylight and time pressure had greater IRR than core lab (ICC 0.59 and 0.7 vs. 0.34, respectively). In general, the trainee assigned lower ASPECTS relative to the fellow and expert. The expert showed greatest concordance with CT perfusion ASPECTS (ICC 0.69), and the trainee the least (ICC 0.47).

Conclusion:
The cognitive framework that we propose, which includes top-down and bottom-up constraints on visual perception, can explain variability in ASPECTS interpretation on NCCT.
Abstract TP67: Active Arterial Fibrillation at the Time of Stroke is a Strong Predictor of Post-Stroke Death
Authors: Zhang Bin , Feng Wayne , Zhao Yuwu
Published: October 2018

Background:
Based on literature, it was not clear whether patients with active atrial fibrillation (AF) at the time stroke would have poorer outcomes. In this study, we aimed to compare the outcomes the group of patients with active AF with other group with history of AF at the time of stroke.

Methods:
We retrospectively identified acute ischemic stroke patients presenting to our stroke centre from January 2015 to December 2016 within 3 days onset of stroke symptoms. Presenting characteristics, baseline NIHSS score, symptomatic intracranial haemorrhage (sICH)(ECASS III criterion) rate, and mortality rate in 30 days was compared. Multivariate analyses were performed.

Results:
A total of 863 acute ischemic stroke patients were included. Of those, 135(15.64%) patients had AF history; 125 (14.48%) patients with active AF confirmed by Electrocardiogram in the emergency room. Except the hypertension history, other basic character of each group had no significant difference. The sICH rate in 7 days was 3.24% in total, and 8.89% (p<0.001, compared with total) in AF history patients, 9.6% (p<0.001, compared with total) in active AF patients. The mortality rate in 30 days was 10.8% in total, and 16.3% (p<0.001, compared with total) in AF history patients, 25.6% (p<0.001, compared with total) in active AF patients. Further, according to the AF condition, we separate patients with AF into three groups: the patients with AF history accompanied with active AF(AF&active-AF, n=87); the patients with AF history without active AF (AF, n=48); the patients with active AF without AF history (active-AF, n=38). The baseline NIHSS score was higher in the AF&active-AF patients (13.85±8.75, p<0.05 ). The mortality rate in 30 days was higher in the active-AF patients (28.9%, p<0.05), and lowest in the AF patients (2.08%, p<0.05). There is no difference in the rate of sICH among three groups. AF onset confirmed by Electrocardiogram in emergency independently predicted 30-day death rate (p=0.004).

Conclusions:
Active atrial fibrillation at the time of stroke is a strong predictor of post-stroke death in 30 days.
Abstract TP96: MiR-34a Targets Cytochrome c and Shapes Stroke Outcomes
Authors: Ren Xuefang , Hu Heng , Provencher Edward , Rellick Stephanie , Farooqi Imran , Sarkar Saumyendra , Grasmick Kimberly
Published: October 2018

Background:
The blood-brain barrier (BBB) is a crucial interface between the central nervous system (CNS) and the circulatory system that maintains cerebral homeostasis by selectively allowing entry of blood solutes into the CNS. BBB dysfunction has been observed in cerebrovascular diseases and neurodegenerative disorders such as stroke. The BBB is opened during stroke, having negative impacts on stroke outcomes. Mitochondria are key players in this abnormal opening of the BBB, and decreased cytochrome c (CYC) levels have been shown in the mitochondrial fraction in stroke. We have recently demonstrated miR-34a regulates the BBB by targeting CYC
in vitro
.

Objective:
To investigate the role of miR-34a in stroke and verify its target CYC
in vivo
.

Methods and Results:
Using a murine transient middle cerebral artery occlusion (tMCAO) model, we demonstrate elevated miR-34a expression in serum and primary cerebral endothelial cells (CECs) from stroke mice. We report that deficiency of miR-34a significantly reduces BBB permeability and improves stroke outcomes. CYC is decreased in the ischemic hemisphere from wild-type (WT) but not miR-34a
-/-
mice following stroke reperfusion. Uncoupling of electron flow by a pharmacological inhibitor Carbonyl-cyanide-4-(trifluoromethoxy)phenylhydrazone (FCCP) compromises mitochondrial oxidative phosphorylation (MOP) in cultured CECs and worsens infarction in stroke mice.

Conclusions:
Our study provides the first description of miR-34a and electron flow affecting stroke outcomes, which could lead to a revision of current miR-34a targets and may lead to discovery of new mechanisms and treatments for cerebrovascular and neurodegenerative diseases such as stroke and Alzheimer’s disease.

Key words:
Blood-brain barrier; Stroke; MiR-34a; Mitochondria; Cytochrome c.

Non-standard Abbreviations and Acronyms:
CEC: cerebral endothelial cell CYC: cytochrome c FCCP: Carbonyl-cyanide-4-(trifluoromethoxy)phenylhydrazone MOP: mitochondrial oxidative phosphorylation tMCAO: transient middle cerebral artery occlusion
Abstract WMP10: Correlation of Histopathology of Thrombi With Clinical Features in Acute Ischemic Stroke
Authors: Hamanaka Masashi , Imai Keisuke , Yamazaki Hidekazu , Itsukage Masahiro , Tsuto Kazuma , Yamamoto Atsushi , Ioku Tetsuya
Published: October 2018

Background:
Development of devices for mechanical thrombectomy have increased the chance of retrieval of thrombi.

Purpose:
The purpose of this study was to examine correlations of histopathologic characteristics of thrombi retrieved with mechanical thrombectomy and clinical features in acute ischemic stroke.

Methods:
Among consecutive acute stroke patients treated with thrombectomy at our hospital from October 2010 to July 2017, we retrospectively reviewed those with acute major arterial occlusion from which retrieved thrombi were evaluated histopathologically. Thrombi were classified into three groups according to the erythrocyte (RBC) and fibrin/platelet components: RBC-rich (RBC >70%, group R), fibrin/platelet-rich (RBC <30%, group P), and mixed (RBC 30-70%, group M). Stroke etiology, imaging characteristics, procedures, and angiographic outcomes were compared among the three groups.

Results:
Of the 170 thrombi assessed, 79, 39, and 52 were classified into groups R, P, and M, respectively. Stroke etiology of cardioembolism was significantly more frequent in groups R (65/79) and M (37/52) than in group P (18/39) (p<0.001). A hyperdense artery sign on non-contrast CT (p=0.005) and a susceptibility vessel sign on MRI-T2WI (p<0.001) were more frequent in groups R (61/77 and 47/57) and M (37/50 and 35/41). Recanalization with the Penumbra system was significantly more common in group R (45.6%) than in groups P (25.6%) and M (28.9%) (p=0.047). Total recanalization rates were similar in groups R (74/79), P (37/39), and M (48/52).

Conclusions:
RBC-rich thrombi retrieved with mechanical thrombectomy are associated with stroke etiology of cardioembolism, specific imaging characteristics, and recanalization with the Penumbra system.