bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP204: Large-Artery Infarction in Primary Angiitis of the Central Nervous System
Authors: Topcuoglu M. Akif , Rocha Eva A , Singhal Aneesh B
Published: October 2018

Introduction:
Primary angiitis of central nervous system (PACNS) typically manifests with accumulating small-sized ischemic strokes and white-matter changes. Large-artery infarcts (LA-PACNS) have been observed, however it is unclear whether LA-PACNS is a unique subtype.

Methods:
We compared the clinical/imaging phenotype, predictors, treatment response and prognosis of LA-PACNS and small-vessel PACNS (SV-PACNS) from a cohort of 51 cases meeting published criteria for PACNS (Ann Neurol. 2016;79:882-94) who were managed at our hospital from 1993-2015.

Results:
Overall mean age 51±15 years; 72% men. Six patients (12%, 95% CI: 3%-21%; mean age 55±13 years; 67% men) had LA-PACNS; 4 (67%) presented with discrete stroke syndromes versus 49% in SV-PACNS. The frequency of headache, encephalopathy, seizure and focal deficits were not significantly different however LA-PACNS had more hypertension. CSF, performed in all patients, showed inflammatory changes in 63% SV-PACNS versus 33% LA-PACNS (p=0.4). Brain biopsy was performed in 5 LA-PACNS and 32 SV-PACNS. In LA-PACNS, one had granulomatous angiitis (GACNS), one had amyloid-beta related angiitis (ABRA), and 3 had negative results. In SV-PACNS, 18 (56%) showed abnormal results including lymphocytic/chronic (12), GACNS (5), ABRA (1). There were no significant differences in the frequency of angiographic abnormalities (67% vs 53%), arteriopathy severity score (10±10 vs 8±13), or arterial segment involved. There were no significant differences in the degree of white matter change, microbleeds, or contrast enhancement on MRI however LA-PACNS had more FLAIR dot sign indicating slow flow and collateralization in leptomeningeal arteries (40% vs 5%, p=0.05). Except for two patients with SV-PACNS, all were treated with steroids; 23 SV-PACNS and all LA-PACNS also received cyclophosphamide. The interval from onset to diagnosis was shorter in LA-PACNS (42 vs 110 days) and follow-up duration was similar (5.4±7.5 years vs. 5.9±6.3 years). Mortality (33% LA-PACNS vs 16% SV-PACNS) and full remission (50% vs 62%) were not significantly different.

Conclusions:
In our relatively large cohort of PACNS, LA-PACNS and SV-PACNS showed similar clinical, imaging, angiographic features and outcome.
Abstract TP208: Incidence and Outcome of Iatrogenic Stroke in Post-Menopausal Women
Authors: Saeed Omar , Malik Ahmed A , Qureshi Adnan I
Published: October 2018

Object:
The incidence of iatrogenic stroke has not been determined in cohort studies. We determine the incidence of iatrogenic stroke in a large cohort of post-menopausal women.

Methods:
We analyzed the data for 93,676 women aged 50-79 years who were enrolled in the observational arm of the Women’s Health Initiative Study. We calculated crude and standardized incidence rates over a mean period (±SD) of 12±1 years. We calculated the incidences of iatrogenic and non-iatrogenic stroke adjusted for age and sex based on the 2010 US census. We compared the incidence of using standardized incidence ratio (SIR) with 95% confidence interval (CI). We estimated the 30-day case-fatality rates.

Results:
We identified 150 iatrogenic (141 ischemic and 9 hemorrhagic) and 2425 non-iatrogenic (1993 ischemic and 431 hemorrhagic) strokes. Age-standardized incidence rate per 100 000 was 48.9 (95% CI, 37.1- 6.25) for iatrogenic stroke and 741.9 (95% CI, 690.5 - 795.3) for non-iatrogenic strokes (SIR of 0.07). For ischemic stroke, the age adjusted incidence was 50.2 (95% CI, 38.8-64.8) for iatrogenic and 709.0 (95% CI, 658.2-762.6) for non iatrogenic stroke (SIR of 0.07). Thirty-day case-fatality rate was 9.3% (95% CI, 5.2-15) for iatrogenic stroke and 17.3% (95% CI, 15.7-19.0) for non iatrogenic stroke.

Conclusions:
The incidence of iatrogenic stroke was higher than previously anticipated and 1 of every 15 stokes in post menopausal women was iatrogenic in etiology
Abstract TP211: Gray and White Matter Hemodynamics and Metabolism Measured Using Magnetic Resonance Imaging
Authors: An Hongyu , Sen Souvik , Robertson Kevin , Powers William
Published: October 2018

Background:
Reliable methods used to measure cerebral hemodynamics, metabolism and autoregulation are time-consuming and invasive.

Objectives:
We sought to measure cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO
2
), in the whole brain, gray and white matter and detect physiological changes in humans under normal and ≈10% reductions in mean arterial pressure (MAP).

Methods:
CBF was measured using pseudo continuous arterial spin labeling (pCASL). OEF was measured using a MRI asymmetric spin echo-planar imaging (EPI). The arterial content of oxygen (CaO
2
) was computed. CMRO
2
was calculated using the equation CMRO
2
=CaO
2
xCBFxOEF. Cerebral autoregulation was determined by measuring changes in CBF, OEF and CMRO
2
in response to ≈10% reductions in MAP in stroke-free controls induced by IV Nicardipine infusion. Autoregulation was measured in the whole brain, gray matter and white matter. Autoregulatory Index (AI) was computed using the equation AI = %CBF change/% MAP change supplemented by CBF associated OEF changes.

Results:
A total of 30 subjects were consented (Mean age 31, 93% male, 40% white, 43% black and 17% others). At baseline, CBF was measured in the whole brain (52.5±9.5 ml/100g/min), gray matter (72.0±13.0 ml/100g/min) and white matter (30.2±8.4 ml/100g/min). OEF was measured in the whole brain (0.32±0.02), gray matter (0.33±0.02) and white matter (0.30±0.01). CMRO
2
was measured in the whole brain (3.2±0.8 ml/100g/min), gray matter (4.6±1.1 ml/100g/min) and white matter (1.8±0.5 ml/100g/min). A target of 10% MAP lowering was successfully achieved in 18 subjects, resulting in a change of mean CBF in the whole brain (52 vs. 50, p=0.1), gray matter (72 vs. 69, p=0.2) and white matter (30 vs. 28, p=0.08). This translated to a AI of 0.3 ± 0.9 in the whole brain, 0.2±1.0 in the gray matter and 0.5±1.7 in the white matter. These CBF changes corroborated with no significant changes in OEF and CMRO
2
.

Conclusions:
MR measurement of CBF, OEF and CMRO
2
, in the whole brain, gray and white matter was comparable to measures obtained by invasive methods. Differences in these measures, as well as AI in the gray and white matter, may help understand cerebrovascular diseases that affect white matter such as lacunar strokes.
Abstract TP215: Increased Economic Burden and Low Clinical Impact With Thrombophilia Testing in Adult Acute Ischemic Stroke Patients
Authors: Adams Amber , Roels Christina
Published: October 2018

Background and Purpose:
Thrombophilic states are an uncommon primary mechanism of ischemic stroke in adults. The role of screening for inherited thrombophilia is unclear, but may be considered in cryptogenic stroke. The aim of this study was to assess the clinical utility and costs of thrombophilia testing. A secondary aim was to characterize the demographics and risk factors of tested individuals.

Methods:
Two year, two center, retrospective, observational study of ischemic stroke patients with thrombophilia testing obtained during inpatient admission. Economic burden was calculated as the product of current laboratory costs and test incidence. Effect of panel outcome on treatment was recorded.

Results:
Thrombophilia testing was conducted in 7.8% (226/2900) of all ischemic stroke patients during the study period. 2,808 thrombophilia tests were conducted on 226 patients in a two year period with total cost of $454,138. Clinical management was changed solely based on panel results in four cases (1.8%) and hematology was consulted in 19 cases (8.4%). Most panels (71.2%) were ordered within the first 48 hours of admission while diagnostic testing was ongoing. There was a high prevalence of stroke risk factors in the tested population (Table). 30% of testing was deemed unnecessary due to determination of a non-thrombophilic mechanism for stroke. There was a trend towards venous thrombophilia tests ordered more frequently in subjects with a patent foramen ovale (PFO), but overall venous thrombophilic testing was ordered at a high frequency (87.5% venous panel/ +PFO vs 75.3% venous panel/- PFO, p 0.07).

Conclusions:
Thrombophilia testing yielded low clinical impact while incurring high economic burden in an adult ischemic stroke population. Institutional optimization, particularly with timing of lab ordering, breadth of diagnostic panel, and testing indicators, may enhance use of these tests for clinical decision making while limiting unnecessary health care costs.
Abstract TP221: Untangling Prehospital Delay in Acute Ischemic Stroke: Hints on Increasing the Thrombolysis Rate - a Prospective Cohort Study
Authors: De Marchis Gian Marco , Fladt Joachim , Seiffge David J , Traenka Christopher , Polymeris Alexandros , Sutter Raoul , Bonati Leo , Engelter Stefan , Lyrer Philippe
Published: October 2018

Background:
Delays in the prehospital phase jeopardize the chances for stroke patients to be treated with thrombolysis. However, the causes of prehospital delay remain obscure. We assessed the causes of prehospital delay among patients with acute ischemic stroke.

Methods:
In this prospective cohort study, we included patients admitted to the Stroke Center of the University Hospital Basel, Switzerland, with an acute ischemic stroke. A corresponding positive Diffusion Weighted Imaging MR was required to be included in the study, i.e. patients with no or negative DWI-MR were excluded. Trained study nurses interviewed all patients or their proxies in person at the bedside. The study period spanned from September, 2015 to July, 2017.

Results:
Overall, 321 patients were included. The median NIHSS score was 3 (interquartile range [IQR]: 1-5). Median delay between symptom onset and call for help was 55 minutes (IQR: 10-420). The mode of transportation to the Stroke Center was with paramedics (ambulance or helicopter) for 60 % of patients, without in 40% (private car: n=72; taxi: n=31; public transportation, walk-in or other: n=25). NIHSS was higher in patients transported with paramedics (4 [IQR 2-6] vs. 1.5 [0-3],
P
<0.001). A family physician was consulted immediately prior to hospitalization by 11% of patients (n=35), 89% were admitted directly to the hospital, and the difference in NIHSS was not statistically significant.

The thrombolysis ratio was 25%. After adjusting for NIHSS, the odds of thrombolysis were higher among patients transported with paramedics (adjusted odds ratio [aOR]: 2.4, 95%-CI: 1.2-4.7, P=0.01), and lower among patients with prior family physician consultation (aOR: 0.10, 95%-CI: 0.01-0.77,
P
=0.03).

Conclusions:
One out four patients wait 7 hours or more before calling for help, a considerable delay. Transport with paramedics was associated with increased chances of thrombolysis. One in ten patients consulted a family physician immediately prior to hospitalization, reducing by 90 percent points the chances of thrombolysis. Identifying and informing family physicians who see patients with symptoms of an acute stroke may be a so far underestimated, cost-effective measure to increase the rate of thrombolysis.
Abstract TP223: Then and Now: Temporal Evolution of a Mobile Stroke Unit
Authors: Sheikhi Lila E , Mullaguri Naresh , Buletko A. Blake , Mathew Jason , Thacker Tapan , Taqui Ather , Nocero John , Reimer Andrew P , Rasmussen Peter A , Russman Andrew N , Hussain Muhammad S , Uchino Ken ,   On behalf of the Cleveland Pre-Hosp Acute Stroke Treatment (PHAST) Study Group
Published: October 2018

Introduction:
Mobile stroke units (MSU) deliver pre-hospital intravenous thrombolysis (IVT) to patients with acute ischemic stroke. We hypothesize that time efficiencies with the MSU have improved over time with a dedicated team and experience.

Methods:
We reviewed 100 consecutive patients evaluated on the MSU from July-October 2014 (Group 1), compared to the most recent 100 patients April-July 2017 (Group 2). Collected data including initial NIHSS, patient age, door to CT performance time, door to CT read time, door to needle (DTN) time, alarm to IVT time, MSU scene arrival to departure time, and MSU alarm to back-in-service time were analyzed with rank sum test. Reported times are in medians with interquartile ranges (IQR).

Results:
Initial median NIHSS (6, IQR 3-12, p=0.78) and ages (65 years old, IQR 55-80, p=0.06) were comparable between the groups. Thrombolysis rate was 16% (n=16) in each cohort. Group 1’s DTN time declined from 31 to 23 minutes (p=0.01). Door to CT completion and read times were faster, at 17 versus 25 minutes (p<0.01), and 10 versus 13 minutes (p<0.01) for Group 2 and Group 1 respectively. MSU arrival to departure time also reduced from 43 to 30 minutes (p<0.01), with total MSU utilization time significantly improved from 88 minutes to 74 minutes (p<0.01) in Group 1 compared to Group 2. While alarm to door times extended from 20 minutes to 22 minutes in Group 2 (p=0.03), the alarm to IVT time was reduced from 55 minutes to 41 minutes (p<0.01).

Conclusion:
While the MSU geographical range has extended, the alarm to IVT time has shortened, reflecting a learned experience by a specialized team.
Abstract TP224: Stroke Code Simulation Training Benefits Advanced Practice Providers Similar to Neurology Residents
Authors: Khan Muhib , Baird Grayson , Price Theresa , Tubergen Tricia , Kaskar Omran , De Jesus Michelle , Oostema Adam , Scurek Raymond , Zachariah Joseph , Coleman Robert , Sherman Wendy , Abdelhak Tamer , Smith Brien
Published: October 2018

Introduction:
Neurology led Stroke Teams are becoming imperative in recent care models of acute stroke management. Advanced Practice Providers (APP) are important members of these stroke teams. Code Stroke simulations allow (APP) to gain valuable experience in the evaluation and treatment of a potential stroke patient without compromising patient care. We hypothesized that simulation training would increase advanced practice provider confidence, comfort level and preparedness in leading a Code Stroke similar to neurology residents.

Methods:
Nine advanced practice providers and nine neurology residents each took turns leading a Code Stroke simulation to determine need for intravenous thrombolysis, thrombectomy and blood pressure management on three cases with standardized patients. Emergency medicine physicians and neurologists were preceptors and gave feedback. APPs and residents completed a survey before and after the simulation. Generalized mixed modeling assuming a binomial distribution was used to evaluate change.

Results:
On a 5-point Likert scale (1 - Strongly disagree and 5 - Strongly agree), confidence in leading a Code Stroke significantly increased from (2.8 to 4.5, p<0.01) comfort level in rapidly assessing a stroke patient for thrombolytics increased (3.0 vs. 4.3 p<0.001), making the decision to give thrombolytics increased (2.7 vs. 4.3, p<0.01) and assessing a patient for embolectomy increased (2.6 vs. 4.3, p<0.01); these results held for both APP and residents.

Conclusion:
Simulation training is a beneficial part of medical education for advanced practice providers and should be considered in addition to traditional didactics and clinical training.
Abstract TP227: Emergency Medical Systems Education May Improve Compliance With Pre-Hospital Stroke Triage Protocols
Authors: Dibiasio Eleanor L , Oliver Lori A , Paolucci Gino A , Clark Michael L , Watkins Christina C , Wilks Ann , DeLisi Karen , Yaghi Shadi , Hemendinger Morgan , Baird Grayson , Jayaraman Mahesh V , McTaggart Ryan A
Published: October 2018

Background:
Following the results of randomized clinical trials supporting the use of mechanical thrombectomy (MT) with tPA for large vessel occlusion (LVO) stroke, our state Stroke Task Force convened to 1) update legislation to recognize differences between Primary Stroke Centers (PSCs) and Comprehensive Stroke Centers (CSCs) and (2) update EMS protocols to triage direct transport of suspected LVO patients to CSCs.

Objectives:
Develop an assessment and single-session training curriculum to assess EMS knowledge before and knowledge gained after training on Los Angeles Motor Scale (LAMS) score, its use to correctly triage patients as CSC-appropriate, and our state-wide EMS protocol for stroke. We also aim to share our specific approach and its efficacy with others so our work can be disseminated and implemented elsewhere.

Methods:
We assembled a focus group to develop assessment questions that would mimic real-life conditions EMS personnel operate under. Ten identical pre-post training questions were formulated to assess content provided during the trainings. Content validity was established by ensuring that questions exclusively tested the content of the slides in the training.

Results:
Trainings were provided for 354 EMS professionals throughout the state. Average pre-test score was 52.4% (95% CI 49%-56%). Average post-test score was 85.6% (83%-88%), representing a significant increase. Each of the 10 questions were individually assessed and all showed significant gains in EMS knowledge after training (Figure 1, p<0.0001).

Conclusions:
Structured EMS education can improve knowledge of stroke triage protocols. As EMS protocols are changed to improve triage of suspected LVO patients to CSCs, such educational efforts will be critical to improve compliance.
Abstract TP232: Telestroke and Direct-to-Hub tPA Treatment Rates are Similar at Academic Comprehensive Stroke Program
Authors: Cohen Abigail S , Salerian Justin A , Bernstein Hannah M , Aysenne Aimee M
Published: October 2018

Introduction:
Telestroke is a practical tool to increasing stroke care delivery. Our aim was to investigate whether patients treated with intravenous tissue plasminogen activator (IV tPA) at the spoke sites were treated similarly to the hub.

Methods:
From 7/2015 to 5/2017, 662 consecutive patients were evaluated via telestroke by academic neurologists or vascular neurosurgeons from a comprehensive stroke program for consideration of acute therapeutic interventions. Of 162 patients for whom IV tPA was recommended, 156 were included in our analysis, excluding those who were in-house stroke activations and one pediatric patient. Data was collected from the telestroke database; further information on patients transferred to the hub site was collected from our local Get With The Guidelines-Stroke registry. Two-tailed t-tests were performed to compare the telestroke and direct-to-hub cohorts. Good outcome was defined as discharge to home, an inpatient rehabilitation facility, or AMA.

Results:
Among 655 telestroke activations, 162 received IV tPA, and among 860 direct-to-hub stroke activations, 216 received IV tPA, (24.7% vs 25.1%; p=0.17). Final diagnosis of acute ischemic stroke among treated patients is similar in the transferred telestroke and direct-to-hub cohorts (70.9% vs 63.0%, p=0.27). Of those who received tPA via telestroke, 55 were transferred to the hub site. Forty transfer patients (72.7%) came from a spoke site without access to neurology care. Transfer patients from spoke sites without neurology care had a median NIHSS of 8 vs 15.5 at spoke hospitals with access to neurology care. Direct-to-hub patients showed increased rates of good outcomes as compared to telestroke transfer patients (90.2% vs 74.5%, p=0.002).

Conclusion:
IV tPA treatment rates are similar among the telestroke and direct-to-hub cohorts. Telestroke patients transferred to the hub site and direct-to-hub patients have comparable rates of acute ischemic stroke diagnoses on discharge; however, direct-to-hub patients have greater rates of good outcomes at discharge. While both groups had high rates of good discharge dispositions, further analyses of differences between the groups are needed to evaluate differences in discharge disposition.
Abstract TP238: Accuracy of “Real-Life” Community Wide Prehospital Stroke Detection in San Diego County
Authors: Kenner Brininger Amelia , Olson-Mack Lindsay , Royer Diane , Koenig Kristi L , Hemmen Thomas M
Published: October 2018

Background:
Recent studies have focused on improving prehospital stroke assessment tools, but specificity and sensitivity have been insufficient to reliably detect stroke in the prehospital setting. To assess the ability of emergency medical services (EMS) personnel to identify acute stroke in the field, we compared EMS stroke recognition with receiving medical center discharge diagnosis from a large community-based stroke dataset, the San Diego County Stroke Registry. The registry was founded in 2010 after San Diego County established 16 diverse stroke receiving centers. EMS uses the Cincinnati Prehospital Stroke Scale for screening.

Methods:
We captured all EMS transports in San Diego County from 2013 to 2015. Accuracy of stroke detection by the EMS providers was analyzed by:
a)
coding of stroke related provider impression (PI) by EMS;
b)
“stroke” recorded as the reason the transport destination was selected. All patients with diagnosis stroke on hospital discharge were considered confirmed stroke, and separated by: Acute Ischemic Stroke (AIS), Subarachnoid Hemorrhage (SAH), Transient Ischemic Attack (TIA) or Intracranial Hemorrhage (ICH).

Results:
Between 2013 and 2015, we identified 577,643 EMS transports, 7,425 (1.3%) were diagnosed as stroke by the treating facility (68.2% AIS, 14.4% TIA, 13.6% ICH, and 3.9% SAH).
a)
Of these 7,418 (99.9%) had a coded PI. Stroke related PI was positive in 53.8% (AIS: 55.9%; SAH: 18.1%; TIA: 60.5%; ICH 46.4%).
b)
A recorded reason for destination was found in 6,813 (91.8%) of all stroke patients. Stroke was the coded reason in 16.4% (AIS 16.4%; SAH 8.0%, TIA 18.0%, ICH 17.3%).

Conclusion:
In a large community EMS system, using routine stroke screening, 53.8% of all stroke patients were identified by EMS. Stroke was the coded reason for the selected destination in only 16.4% of EMS transported stroke cases. This emphasizes the need for better prehospital stroke detection to improve triage and direct patient care.
Abstract TP245: Smartphone App Can Precisely Share Neuroimaging for Stroke Team
Authors: Sakai Kenichiro , Komatsu Teppei , Maku Takahiro , Asahara Yuki , Takao Hiroyuki , Iguchi Yasuyuki , Murayama Yuichi
Published: October 2018

Background and Objectives:
Bland new smartphone application (JOIN) can provide sharing text, neuroimagings, photos, and videos among stroke team with high security. Our aim is to investigate the diagnostic accuracy and agreement of DWI-ASPECTS between JOIN and conventional PC monitor.

Methods:
This study used the MRI images of consecutive acute stroke patients having main artery blockage (ICA and/or MCA). After concealing patient backgrounds, two vascular neurologist independently graded ischemic change on DWI-ASPECT by using JOIN and conventional PC monitor, respectively. All patients were estimated DWI-ASPECT≥6 or <6 (DWI cut-line) according to AHA/ASA GUIDELINE for endovascular treatment. Then, we analyzed inter-device (JOIN and PC monitor) and inter-rater (vascular neurologist 1 and 2) agreements of DWI cut-line. Additionally, detection rates of JOIN were compared for each DWI-ASPECTS region between vascular neurologist 1and 2.

Results:
We analyzed the cases of 50 subject patients (67% male, average age 66 ± 11, median NIHSS score 7). Between JOIN and PC monitor, the inter-device agreement of DWI cut-line was significantly excellent (vascular neurologist 1;κ=0.80, p<0.001, vascular neurologist 2; κ=0.77, p<0.001) .The inter-rater agreements between vascular neurologist 1 and 2 were also satisfactory by using JOIN (κ=0.68, p<0.001), and PC monitor (κ=0.60, p<0.001). The average interpretation duration (from recognizing image to finishing interpretation) of JOIN and PC monitor were similar (vascular neurologist 1; 1.7 min of JOIN vs. 1.6 min of PC monitor (p=0.64) and vascular neurologist 2; 2.4 min vs. 2.0 min (p=0.14). Between vascular neurologist 1 and 2, DWI-ASPECTS lesion of JOIN were detected in the M1 (32% vs. 34%, p=0.83), M2 (30% vs.38%, p=0.39), M3 (30% vs.34%, p=0.67), M4 (38% vs.24%, p=0.13), M5 (76% vs.44%, p<0.001), M6 (38% vs.36%, p=0.84), caudate head (14% vs.12%, p=0.77), insular cortex (48% vs.50%, p=0.84), lentiform nucleus (18% vs.34%, p=0.06), and internal capsule (16% vs.10%, p=0.37), respectively.

Conclusion:
By using smartphone App, stroke neurologists are able to estimate DWI-ASPECTS precisely and quickly. Outstanding App “JOIN” should yield a profit of acute stroke care.
Abstract TP248: Identifying Characteristics of Patients With Suspected Stroke by Paramedics but not by Emergency Medical Dispatchers Using Natural Language Processing and Machine Learning
Authors: Richards Christopher T , Garg Ravi P , Mendelson Scott J , Stein-Spencer Leslee , Prabhakaran Shyam
Published: October 2018

Introduction:
Accurate stroke identification during 9-1-1 calls by emergency medical dispatchers (EMDs) results in improved acute stroke care, but EMDs only identify 50% of strokes. Structured analysis of 9-1-1 calls has identified words and phrases used by laypersons associated with stroke; however, the words and phrases used by paramedics to describe suspected stroke patients, when EMDs do not suspect stroke, have not been reported.

Hypothesis:
Key words and phrases in the free text of prehospital records for patients suspected of having acute stroke by paramedics but not by EMDs can be identified by natural language processing (NLP) and machine learning.

Methods:
In an emergency medical services (EMS) system with a single municipal fire-based EMS provider agency and a central dispatch center with standardized protocols, we performed a retrospective study of de-identified prehospital records of patient encounters between January 2013 and December 2016 where paramedics suspected stroke. Using NLP, we identified and extracted 2,500 candidate features from free-text sections of the prehospital patient care report and transformed the dataset into two separate document-feature matrices where: a) EMDs and paramedics concurred on stroke impression and b) EMDs and paramedics were discordant. Latent Dirichlet Allocation, a topic-modeling technique, was used to cluster features into 50 topics, which were then compared to identify key words. We also used machine learning model linear support vector machines to select other key words.

Results:
Among 9,436 EMS suspected stroke encounters, EMDs identified acute stroke in 4,761 (50.5%) of cases. The following words and phrases were used by paramedics in cases where EMDs did not identify stroke: “blunt head trauma,” “blurred double vision,” “blurry vision,” “mastectomy,” “hypothyroidism,” “dysrhythmia,” and “tachypnea.”

Conclusions:
NLP and machine learning can identify words and phrases in free-text sections of prehospital records of patients in which paramedics suspected stroke and EMDs did not. Adapting EMD protocols to include specific words and phrases consistently used by paramedics to describe patients with acute stroke may help improve EMD recognition during the 9-1-1 call.
Abstract TP250: The Stroke 1-2-0 Strategy is Well Accepted by Community Physicians in China
Authors: Zhao Jing , Liu Renyu
Published: October 2018

Background:
While FAST (Face, Arm, Speech, Time) has been used in China for stroke awareness and rapid response education, however, the effectiveness is unclear due to the language barrier, and the stroke related mortality remains very high. We recently engineered Stroke 1-2-0 for China based on FAST.[1] This investigation aimed to investigate its acceptance in community physicians.

Method:
This investigation protocol was approved by the Institutional Review Board of the Minhang Hospital affiliated to Fudan University. Questionnaire is distributed to community physicians or family doctors (total of 247 physicians). An educational session was planned to teach both FAST and Stroke 1-2-0 for the participants before and after educational session to evaluate the awareness of stroke, stroke recognition tool and the acceptance of the stroke recognition tool.

Results:
In educational sessions consisting of 247 family physicians (82 male and 165 female), 98.79% of the survey responders are at the age range of 21-60 years old in two major cities (Shanghai and Hangzhou). Only 10.53% of the participants know that the thrombolytic therapeutic window is 4.5 hours. 28.74% of the participants select time points more than 4.5 hours. Only small portion of physicians in the community know FAST (36.44%) or Stroke 120 (39.27%) as a stroke recognition tool. After the training session, majority of the participants understand that the therapeutic window for ischemic stroke is 4.5 hr as compared to a small portion before the educational session (10.53%). Majority of the participants mastered Stroke 1-2-0 (98.79%) and FAST (98.79%) immediately after the training session. However, 97.17% of the participants believe that Stroke 1-2-0 is the most suitable program in China in stroke education. Only seven participants believe that FAST is a still better tool for Chinese.

Conclusion:
While community physician play critical role in patient education, a significant knowledge deficiency for stroke awareness is identified. Despite both Stroke 120 and FAST can be mastered easily by community physician, they believe Stroke 1-2-0 should be used for stroke awareness education and rapid action for the public domain in China.
Abstract TP262: Evaluation of Novel Structural Features in Neovascularization of the Ischemic Brain
Authors: Jiang Hao , Kurth Florian , Liou Raymond , Albert Ryan , Gonzalez Nestor R
Published: October 2018

Introduction:
Evaluation of angiogenesis and neovascularization in stroke has been limited to measurements of vascular density and identification of newly formed vessels. However, structural aspects of the configuration of those new vessels have not been studied. We investigated structural features of micro neovascularization in an animal model of cerebral ischemia.

Methods:
We used a mice model of ischemia and synangiosis. In essence, C57/BL6J mice underwent MCA ligation via a temporal craniotomy, the temporalis muscle was apposed to the ischemic brain and animals were sacrificed after 4 weeks. CD31-stained vasculature was evaluated by confocal microscopy. Images were analyzed using Fiji’s Skeleton and Direction tools. Vessel directionality was assessed as the proportion of vessels running along the predominant vector direction. Branching pattern was quantified as the junction points per vessel.

Results:
Vascular density was increased on the experimental side (CD31+: 7.17% vs. 5.13%, p < 0.01), consistent with neovascularization. On the experimental side, increased parallelism of the vessels was observed (14% vs. 8% p = 0.01), and reduced branching (control-experimental= 0.027+/- 0.01 p = 0.001), as expected for more immature vessels.

Conclusion:
Increased parallelism and reduced branching are structural features of neovascularization after ischemia-revascularization in this model. Future studies including different time-points could clarify the evolution of these changes.
Abstract TP267: Uncertainty-Based Individual Health Preferences for Patients With Primary Intracerebral Hemorrhage
Authors: Slaughter Kristen B , Meyer Ellie G , Meeks Jennifer R , Bambhroliya Arvind B , Bowry Ritvij , Ahmed Wamda O , Gealogo Gretchel A , Warach Steven , Tyson Jon E , Miller Charles C , McCullough Louise D , Wu Tzu-Ching , Begley Charles E , Savitz Sean I , Vahidy Farhaan S
Published: October 2018

Introduction:
Value-based care and patient-perceived outcomes are increasingly important. Standard Gamble (SG) derived utilities directly measure patients’ preferences for health states and form the basis of health economic analyses. We describe distribution of and factors associated with SG utilities (SGU) in a cohort of intracerebral hemorrhage (ICH) patients, and explore changes in SGU over 90 days post-discharge.

Methods:
Our study is a multisite cohort aiming to evaluate the comparative effectiveness of ICH patient management at various levels of care across Texas. Consented patients undergo assessments including SG in-hospital, and 30 and 90 days post-discharge. The SG assesses patients’ risk-taking behavior toward achieving a perfect health status, and outputs utility on a scale of 0 - 1 (Figure 1). Median and interquartile range (IQR) are reported for inpatient and day-90 SGU. Quantile regression was used to evaluate factors associated with SGU. Difference in median (DIM) and 95% confidence interval (CI) for the difference are reported.

Results:
158 patients have been enrolled. Inpatient and day-90 SG was obtained from 132 and 54 patients respectively. Median inpatient SGU are significantly lower for older patients, white patients (compared to black patients), and those with higher ICH scores (Table 1). Median day-90 SGU was higher than inpatient SGU (DIM: 0.27; 95% CI: 0.08-0.46). Age >65 and higher ICH score were independently associated with lower SGU (Age: DIM -0.30; 95% CI -0.49, -0.11) (ICH Score: DIM -0.59; 95% CI -0.97, -0.21). Patients with mRS scores 0-3 at day 90 had higher SGU values compared to those with mRS scores 4-5 (DIM: 0.25, 95% CI: 0.09 - 0.41). Enrollment continues; updated analyses to be presented.

Conclusion:
Direct assessment of preferences for a morbid condition like ICH provides unique insight into patient values. Assessment of SGU may be routinely conducted in ICH patient studies to generate evidence for comparative effectiveness.
Abstract TP273: Stroke Pit Stop Decreases Door to Needle Time
Authors: Gomes McGillivray Celia , Le Jacqueline , Stang Claude , Gaffud Gerald , Clark Thomas , Claycomb Robert J
Published: October 2018

Background:
The American Stroke association has set targets for certified stroke centers achieving door to needle times within 60 minutes for 75% of cases, and less than 45 minutes for half of the cases. For each 15 minute reduction in delay, an estimated 4% improvement is realized in clinical outcomes. However, many barriers interfere with the hospital’s ability to attain a reduction both in clinical decision making and treatment times.

Purpose:
This quality improvement project examined the impact of a work flow re-design using a Stroke "Pit Stop" protocol. The project was designed to improve patient care and determine appropriate institutional practices at our hospital by evaluating patient outcomes.

Methods:
A protocol was developed where stroke code patients was rapidly evaluated for tPA candidacy and tasks were simultaneously completed by physicians, nurses, and ancillary staff prior to CT imaging. All code stroke cases from a single hospital were evaluated 6 month pre (2016 July-December), and 6 months post (2017 January - June) intervention. Average door to needle, proportion of cases below 60 minutes and 45 minutes were compared between the two time periods.

Results:
Mean door to needle time statistically significantly decreased from 63 ± 33 minutes to 46 ± 13 minutes (p= 0.044). Furthermore, the percentage of patients receiving tPA under 60 minutes and under 45 minutes increased from 63% to 79% and from 29% to 47% respectively.

Conclusion:
Instituting the Stroke "Pit Stop" statistically significant decreased door to needle times helping the hospital meet national guidelines.
Abstract TP274: HMGB1 is Regulated by Microrna in Patients With Ischemic Stroke
Authors: Jickling Glen , Ander Bradley P , Shroff Natasha , Hamade Farah , Stamova Boryana , Dykstra-Aiello Cheryl , Liu Dazhi , Sharp Frank R
Published: October 2018

Background:
High mobility group box 1 (HMGB1) is a strong inducer of inflammatory pathways in ischemic stroke, and a marker of worse neurological outcome at 1 year. As such HMGB1 may contribute to secondary brain injury and decline in ischemic stroke. We sought to understand the regulation of HMGB1 by microRNA in patients with ischemic stroke and the relationship to stroke severity.

Methods:
In 106 ischemic stroke patients and 106 vascular risk factor controls levels of HMGB1 were compared in relationship to levels of microRNA. HMGB1 in plasma was measured by ELISA. microRNA isolated from circulating leukocytes were measured by microarray and confirmed by RT-PCR. HMGB1 regulation by identified microRNA were assessed both in-silico and in-vitro by luciferase assay.

Results:
HMGB1 is increased in ischemic stroke patients compared to controls (p<0.05) in a manner that is related to severity of stroke. An increase in admission NIHSS is associated with an increase in HMGB1. The increase in HMGB1 corresponded with a decreased in microRNA let7i. Direct regulation of HMGB1 was shown for microRNA let7i. When HMGB1 levels were adjusted for let7i, the association with NIHSS was no longer present.

Conclusions:
HMGB1 is increased in patients with stroke and correlates with stroke severity. microRNA regulate HMGB1 in patients with stroke and may be an important mediator of immune activation associated with secondary ischemic brain injury.
Abstract TP275: Modelling the Impact of Mobile Stroke Unit Dispatcher Accuracy on Patient Outcomes
Authors: Holodinsky Jessalyn K , Kamal Noreen , Zerna Charlotte , Zhu Luke , Hill Michael D , Goyal Mayank
Published: October 2018

Introduction:
Ischemic stroke with large vessel occlusion (LVO) cannot be definitively diagnosed without imaging. The Mobile Stroke Unit (MSU) has brought this capability (along with alteplase administration) to the field. In areas with widespread urban sprawl, having MSUs stationed in the community may improve patient outcomes. However, this is also dependent on how accurately dispatch can assess suspected stroke with LVO over the phone. We compare the probability of good outcome for patients taken direct to Comprehensive Stroke Centre (CSC) (mothership) vs utilizing a MSU at varying levels of dispatcher accuracy in identifying ischemic stroke with suspected LVO.

Methods:
Conditional probability models for patients with suspected LVO for mothership and MSU scenarios were generated. The positive predictive value (PPV) of dispatcher screening was varied from 25% to 75%. A sliding dichotomy was used to define good outcome, mRS 0-2 at 90 days was used for LVO patients and mRS 0-1 was used for non-LVO patients. Data from the HERMES collaboration was used for EVT patients, data from the Emberson meta-analysis (extrapolated to the HERMES population for LVO) was used for alteplase treated patients. Probability of good outcome for intracranial hemorrhage and stroke mimics was considered time invariant.

Results:
The results are visualized using temporal-spatial diagrams with one CSC and four MSUs stationed around the CSC with each MSU covering one quarter of the city. If dispatcher accuracy is poor the area where MSU predicts the best outcome is large as more non-LVO strokes, which benefit from fast alteplase, will be picked up. However, as dispatcher accuracy in identifying LVO increases the mothership areas also increase as the MSU would impose delays in these patients receiving EVT.

Conclusions:
The ability to accurately dispatch the MSU to patients with suspected LVO impacts transport decision making. This should be considered when designing a stroke system containing a MSU.
Abstract TP276: Health-Related Quality of Life Indices for Patients with Primary Intracerebral Hemorrhage
Authors: Bambhroliya Arvind B , Meyer Ellie G , Meeks Jennifer R , Slaughter Kristen B , Bowry Ritvij , Ahmed Wamda O , Gealogo Gretchel A , Warach Steven , Tyson Jon E , Miller Charles C , Begley Charles E , Savitz Sean I , Vahidy Farhaan S
Published: October 2018

Introduction:
Assessments of health-related quality of life (QoL) are increasingly important for stroke patients; however, such data are lacking for patients with intracerebral hemorrhage (ICH). Using EuroQol-5 Dimension-5 Level (EQ5D), we describe factors associated with QoL, and explore associations between QoL and functional outcomes in ICH patients.

Methods:
Our study is a multisite prospective cohort aiming to examine comparative effectiveness of treating ICH patients at various levels of care across Texas. Consented patients undergo QoL assessments - including EQ5D - in-hospital and 90 days post-discharge. EQ5D health utility values (HUV) were calculated using published utility weights for US population. HUVs range from -0.11 to 1.00, with 0.00 and 1.00 representing patient-perceived QoL equivalent to death and perfect health, respectively. Median and interquartile range (IQR) are reported. Quantile regression was used to evaluate factors associated with HUVs, and we report difference in median (DIM) and 95% confidence interval (CI) for the difference.

Results:
Thus far 158 patients have been enrolled in the study. EQ5D HUVs were obtained from 133 patients in-hospital and 62 patients at day 90. Median in-hospital and day-90 HUVs were significantly lower for patients with higher NIHSS and ICH scores. Patients with in-hospital complications, neurosurgical procedures, and longer length of stay also had lower HUVs (Table 1). There was a significant improvement in HUVs during 90-days post-discharge (DIM: 0.37; 95% CI: 0.24-0.51), and high day-90 HUVs were associated with good functional outcome (mRS 0-3) (Figure 1, DIM: 0.65, 95% CI: 0.51-0.78, p<0.001). Enrollment continues; updated analyses to be presented.

Conclusion:
Our results indicate a correlation between QoL, and inpatient clinical parameters and functional outcomes. Assessment of QoL may be routinely conducted in ICH studies to generate evidence for comparative effectiveness.
Abstract TP28: Influence of Ballon Guide Catheter Cathterization on Mechanical Thrombectomy in Acute Stroke Patients
Authors: Jeong DaEun , Kim Dong Joon
Published: October 2018

Background and purpose:
Mechanical thrombectomy (MT) with proximal flow control and negative aspiration may improve the outcome of endovascular revascularization therapy (ERT) for acute stroke patients. The purpose of this study is to compare the effects of balloon guide catheter (BGC) catheterization on benchtop tests and in patients treated for anterior circulation acute ischemic stroke using mechanical thrombectomy.

Method:
A benchtop test was performed with a silicone cerebrovascular model. The negative suction pressure was compared according to the catheterization location {proximal; placement of BGC proximal to atlas vertebral body(2nd, 3rd and 4th cervical vertabra) , distal; Placement of BGC is the skull base or upper side of atlas vertebral body lower margin}of the BGC. The influences of the BGC was analyzed in acute stroke patients with large anterior circulation occlusion. The baseline clinical characteristics, procedural variables, recanalization rate and clinical outcomes were compared.

Result:
The benchtop test showed that the distally located balloon showed 11 % increase in suction pressure. The clinical analysis included 104 patients (age: 70.1±12.3 70). The locations of the BGC inflations were distal (n=47) and proximal (n=57) groups. Proximal BGC group was more frequently associated with hypertension (77% versus 57%; P=0.031). The recanalization rate was significantly higher in the distal BGC group (95.7% versus 66.7%;
P
<0.0001). Needle to recanalization time is more shorter in distal balloon group than proximal balloon group (48.57 ± 26.1 VS 68.3 ± 44.8 P = 0.005). The incidence of emboli to new territory (ENT) was less frequent in the distal BGC group.

Conclusions:
Catheterization of the BGC may have influences on the recanalization of occluded anterior circulation arteries in acute stroke patients. The BGC should be navigated as distally as possible in the cervical ICA for maximally effective thrombectomy.
Abstract TP285: Improving Mobile Stroke Unit Intravenous Thrombolysis Times Through Parallel Processing
Authors: Sheikhi Lila E , Mullaguri Naresh , Nocero John , Reimer Andrew P , Schrock Jon , Rasmussen Peter A , Russman Andrew N , Uchino Ken , Hussain Muhammad S ,   On behalf of the Cleveland Pre-Hosp Acute Stroke Treatment (PHAST) Study Group
Published: October 2018

Introduction:
Mobile stroke units (MSU) provide pre-hospital delivery of intravenous thrombolysis (IVT) in the setting of acute ischemic stroke. We hypothesize continued experience with MSU leads to improved DTN times and we aim to identify contributing process factors related to earlier IVT decisions.

Methods:
We reviewed all patients who received IVT on the MSU from 2014-2017. Process metrics included door to doctor (telemedicine log-in time), door to CT performance time, and door to needle (DTN) times. Times are reported as medians with interquartile ranges (IQR). We analyzed the individual factors compared to DTN time with linear regression.

Results:
A total of 124 patients have received IVT since our MSU initiation in 2014. The population’s median age was 63.5 (range, 25-99) years old with initial NIHSS 9 (IQR 6-16). The total group’s DTN median times was 29 minutes (IQR 29-38, fastest time 11 minutes), with a linear relationship showing improvement in DTN times since MSU initiation (p=0.01). Door to CT performance times have improved over time (14 minutes, IQR 9-18, p<0.01). There was a strong linear relationship (figure) between lower DTN times and early door to doctor access times (8 minutes, IQR 6-12, p<0.01).

Conclusion:
Earlier door-to-doctor access in a MSU suggests a role of parallel processing in shorter IVT decisions.
Abstract TP29: Endovascular Therapy for Distal Occlusions in the Early and Late Window: an Extension in Location and Time
Authors: Sarraj Amrou , Veznedaroglu Erol , English Joey , Budzik Ronald , Baxter Blaise , Bartolini Bruno , Liebeskind David S , Krajina Antonin , Nogueira Raul , Farrell Christine M , Shields Ryan , Zhang Yanchang , Malek Ali ,   Trevo Retriever Registry Investigators, Vora Nirav A , Chen Michael , Hassan Ameer , Gupta Rishi
Published: October 2018

Background:
Endovascular therapy (EVT) effectiveness is established in ischemic strokes with large vessel occlusion (LVO) in the terminal ICA and M1, which was extended up to 24 hrs by recent DAWN trial results. However this benefit is not as well established in more distal (M2) occlusions, especially late presenters (beyond 6 hrs). We evaluated thrombectomy outcomes in M2 occlusions as compared to ICA/M1 across early and late time windows.

Methods:
In a prospective, multicenter, single arm, international registry (Trevo Retriever Registry), anterior circulation LVOs were stratified on clot location into M2 vs ICA/M1 and dichotimized into early vs late (0-6 vs 6-24 hrs). 90 day mRS (0-1 excellent, 0-2 good) were the primary outcomes; sICH and dissection were the secondary (safety) outcomes. Multivariate analyses identified pre-procedure variables independently correlating with good outcome in M2s.

Results:
1581 patients were identified (1265 ICA/M1, 316 M2). The M2 and ICA/M1 groups were similar (age in both 68.4), IV-tPA (69.1 vs 69.7%, p=0.8) and same median/IQR ASPECTS 8 (7-9). M2 patients had lower NIHSS (13 vs 16, p<0.001). Higher good and excellent outcomes were observed in M2s (65.8% and 51.3%) compared to ICA/M1 (57.9% and 42.8%) (p=0.01). Similar outcomes were maintained beyond 6 hrs (64.8% good, 45.9% excellent in M2s vs 53.8% and 38.4% in ICA/M1) (p=0.08). Fig 1 shows the probabilities of good outcome in M2 vs ICA/M1 in relation to time, illustrating no association with time (p=0.4). Similar safety profiles were seen: sICH (0% M2 vs 0.7% ICA/M1, p=1.0) and dissections (0.3% M2 vs 0.4% ICA/M1, p=0.22). Age (aOR 0.96, 0.94-0.98 95% CI, p<0.001) and NIHSS (aOR 0.94, 0.9-0.98 95% CI, p<0.001) correlated with good outcome in M2, while IV-tPA did not have adjunctive benefit (aOR 0.72, 0.42-1.24 95% CI, p=0.24).

Conclusion:
Excellent and good outcomes may be achieved in distal LVO isolated to M2 similar to those with proximal occlusions. A benefit that can be reached up to 24 hrs.