bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP73: Intra-arterial Transfer Time Metrics Study—Southern California Kaiser Permanente and University of Texas Houston Telestroke Network Experience
Authors: Wu Tzu-Ching , Sangha Navdeep , Elorr Feryal N , Olivas Edgar , Ankrom Christy M , Borzorgui Shima , Bambhroliya Arvind B , Jagolino Amanda L , Cossey Tiffany D , Savitz Sean I
Published: June 2021

Background:
The transfer process for patients with large vessel occlusions from a community hospital to an intra-arterial therapy (IAT)-capable center often involves multiple teams of physicians and administrative personnel, leading to delays in care.

Objective
We compared time metrics for spoke drip-and-ship telemedicine (TM) patients transferred for IAT to comprehensive stroke centers (CSC) in two different health systems: Kaiser Permanente (KP) with an integrated health care system of spokes and a 50 mile range using ambulances for transfer vs UTHealth (UTH), where patients are transferred by helicopter from varying health systems ranging up to 200 miles from the hub.

Methods:
We retrospectively identified patients in the KP and UTH networks transferred from TM spokes to the CSC (KP—6 spokes and UTH -17 spokes). From 9/15 to 4/16, a total of 79 TM patients (KP-28 patients, UTH-51 patients) were transferred to the respective hubs for evaluation of IAT. Baseline clinical data, transfer, and IAT metrics were abstracted.

Results:
On average, it takes ~90 minutes for a TM patient to arrive at the CSC hub once accepted by the transfer center. Patients in the KP Network arrive at the hub faster than UTH patients, but IAT metrics/outcomes are comparable. Over 50% of the patients did not undergo IAT on hub arrival mostly due to lack of clot on CTA (20/45) or symptom improvement (9/45).

Conclusion:
In two large, yet different TM networks, the transfer time from spoke to hub needs to be shortened. Areas for improvement include spoke arrival to transfer acceptance and transfer acceptance to hub arrival. A prospective study is underway to develop best practice time parameters for this complex process of identifying and transferring patients eligible for IAT.
Abstract TMP78: Time From Consult Page to Tissue Plasminogen Activator Treatment Over Telestroke Decreases With Experience
Authors: Jagolino Amanda L , Bozorgui Shima , Bambhroliya Arvind B , Ankrom Christy M , Cossey TC D , Trevino Alyssa D , Savitz Sean I , Wu Tzu Ching , Vahidy Farhaan
Published: June 2021

Introduction:
Formal telestroke (TS) training for neurovascular fellows (NVFs) is necessary due to growing gaps in acute ischemic stroke (AIS) coverage, yet educational approaches are not well-characterized. Time between when a TS consultant is paged and tPA administration (page-to-needle time, PTNT) can provide an objective measure of proficiency in TS management of AIS.

Hypothesis:
We hypothesized that NVFs have longer PTNT than neurovascular attendings (NVAs), and PTNT improves with increasing number of TS consults.

Methods:
We identified suspected AIS patients in our TS registry (7/2013-6/2016) who received tPA while being evaluated remotely by video consultation at one of 17 spokes. Using multivariable quantile regression, we estimated the difference, and 95% confidence interval (CI) of the difference, for median PTNT between NVFs and NVAs. We also report the coefficient of change in PTNT over increasing number of TS consults.

Results:
Table 1 depicts baseline characteristics. NVFs evaluated 53.7% of 618 tPA cases over TS. NVAs took less time to administer tPA, difference in median PTNT (95% CI): -9 min (-12.3 to -5.7). This difference persisted when adjusted for relative tPA contraindications. For each additional TS consult, PTNT was decreased by 0.07 min for NVFs or NVAs (p=0.02 and <0.01, respectively) (Figure 1).

Conclusion:
TPA metrics improve with increasing number of TS consults for NVFs and NVAs. PTNT improves by 1 min for approximately every 14 TS consults. Our findings support the importance of integrating TS training into a supervised neurovascular fellowship to increase NVF proficiency in TS prior to independent practice.
Abstract TMP79: Does Race or Socioeconomic Class Matter in Socialized Medicine? A Retrospective Analysis of Stroke cost and outcomes in US Military Health Care System
Authors: Price James , Blattner Matthew , Holtkamp John , Holtkamp Matthew
Published: June 2021

Introduction:
The racial disparity of stroke outcomes is well documented in the US Civilian Healthcare system. In contrast, the Military Healthcare system is a single payer system (Every member has the same health benefits). Does this affect outcomes?

Hypothesis:
We hypothesize there will be no difference in Healthcare outcomes within the Military Healthcare system when the effects of race and rank (socioeconomic surrogate) are considered.

Methods:
Data was collected from the Defense Health Agency Military Mart (M2) database from fiscal year 2010 to 2016 (All admissions to military care facilities). The M2 database stores data including rank and race. Adult patients with a primary diagnosis of stroke at discharge (International Classification of Diseases, 9th Revision codes 434.91, 434.11 or 10
th
Revision code I63.9) were reviewed. Race and Rank were compared for Duration of hospitalization, total Cost of the hospitalization and Outcome (disposition status) using Multivariate Analysis.

Results:
A total of 3,910 patients discharged from Military hospitals were identified. The racial composition of this sample was: White 50.1%, Black 17.3%, Asian 7.2%, Other 2.9%, and Unknown/Not Reported 22.5%. There was no correlation between race and Duration of hospitalization, total Cost of the hospitalization or Outcome. Military Rank was identified with 2,134 (54.6%) of the 3,910 patients in the study. The Rank identified study population was: Senior Enlisted 71.4%, Senior Officers 18.2%, Junior Enlisted 4.9%, Junior Officers 2.9% and Warrant Officers 2.5%. There was no correlation between Rank and Duration of hospitalization or total Cost of the hospitalization. There was a statistically significant trend to better Outcome for higher rank then lower (p<0.05).

Conclusions:
Racial disparities evident in the Civilian Healthcare system do not appear to transfer to the Military Healthcare system. Rank (as a socioeconomic surrogate) did have a trend toward better Outcomes with higher rank.
Abstract TMP84: Percutaneous Gastrostomy Tube, but not Tracheostomy, Predicts 30-Day Readmissions in Spontaneous Intracerebral Hemorrhage: An Analysis of the 2013 Nationwide Readmissions Database
Authors: Hays Shapshak Angela , Donnelly John P , Vahidy Farhaan , Albright Karen C
Published: June 2021

Background:
Spontaneous intracerebral hemorrhage (sICH) is associated with substantial disability, accounting for considerable resource utilization among stroke survivors. Debate exists about the timing and utilization of tracheostomy (Trach) and percutaneous gastrostomy (PEG) tube placement in sICH patients. We hypothesized that sICH survivors with PEG and/or Trach would have higher odds of 30-day readmission.

Methods:
We analyzed the 2013 Nationwide Readmissions Database, a nationally representative sample of hospital discharges. Patients with a primary discharge diagnosis of sICH (ICD-9 code 431) were included in the analysis. Repeat, pediatric, same-day events, head trauma, AVM/fistula, and discharges occurring in December were excluded. Patients who received PEG and/or Trach were identified using published algorithms. We defined readmission as any admission within 30-days of index hospitalization discharge. Odds ratios for 30-day readmission comparing exposed versus unexposed were estimated with adjustment for demographics, risk factors, and concurrent illness. All analyses were performed using survey design variables.

Results:
Among the 32,715 sICH index hospitalizations, 3,480 (10.6%) received a PEG and 1806 (5.5%) received a Trach. Overall 4,320 (13.2%) were readmitted within 30 days (PEG 20.5%, trach 18.9%). In the fully adjusted models, sICH patients with PEG had higher odds of readmission (OR 1.43, 95% CI 1.14-1.80), while patients with trach did not (OR 0.77, 95% CI 0.54-1.11). Predictors of readmission among individuals with and without PEG and Trach will be presented.

Conclusions:
sICH patients who underwent PEG placement had higher odds of 30-day readmission while patients receiving Trach did not. This finding suggests that heightened post-discharge surveillance of individuals receiving PEG may be warranted.
Abstract TMP85: Frequency and Utility of Repeat Cerebrovascular Imaging Among Hospitalized Stroke Patients
Authors: Raza Syed Ali , Javalkar Vijay , Dehkharghani Seena , Kudrimoti Archana , Saindane Amit , Mullins Mark , Nahab Fadi
Published: June 2021

Background:
There are limited data on the frequency of repeat non-invasive imaging performed in the evaluation of stroke patients and its utility in patient care.

Hypothesis:
Stroke patients frequently undergo repeat intracranial arterial imaging with limited change in clinical management.

Methods:
All stroke patients admitted to a comprehensive stroke center from January 1, 2012 through December 31, 2014 were identified as part of a prospective radiology database if they underwent contrast-enhanced MR angiography (CE-MRA) of the head and subsequent CT angiography (CTA) of the head within 7 days. Two vascular neurologists reviewed medical records to confirm the diagnosis of stroke and subtype, determine the indications of the two studies, evaluate if any neurologic change occurred prompting the subsequent CTA, new findings seen on CTA and identification of any change in clinical management based on the CTA results.

Results:
Of 1355 stroke patients who underwent CE-MRA of the head during the study period, 195 (14%) patients underwent subsequent CTA within 7 days, including 33 patients who had non-diagnostic CE-MRA due to patient motion. Of the 162 (12%) patients with diagnostic CE-MRA who underwent subsequent CTA head (mean age 59 ± 15 years, 52% female, 61% ischemic stroke, 11% ICH, 28% SAH), 69 (43%) patients were considered to have an unnecessary CTA of the head. In multivariable analysis, factors associated with an unnecessary CTA head included no new neurological exam changes [OR 7.29; 95% CI 1.92 to 27.63] and same documented indication for CE-MRA and CTA [OR 6.47; 95% CI 3.04 to 13.78]. Changes in clinical management after CTA of the head were seen in 42% of patients who had a clinically indicated CTA versus 7% of patients with a CTA considered unnecessary (p<0.0001).

Conclusions:
Approximately 1 in 8 stroke patients who underwent a diagnostic CE-MRA underwent a subsequent CTA of the head within 7 days and nearly half of these CTA studies were considered unnecessary. The utility of repeat cerebrovascular head imaging with CTA of the head after a diagnostic CE-MRA is low when there is no evidence of a change in neurological exam or when the same indication is documented for both studies.
Abstract TMP86: Early Microvascular Cerebral Blood Flow Response to Head-of-bed Elevation is Related to Outcome in Acute Ischemic Stroke: A Diffuse Correlation Spectroscopy Study
Authors: Gregori-Pla Clara , Delgado-Mederos Raquel , Camps-Renom Pol , Zirak Peyman , Blanco Igor , Cotta Gianluca , Prats-Sánchez Luís , Martínez-Domeño Alejandro , Serra Isabel , Martí-Fàbregas Joan , Durduran Turgut
Published: June 2021

Introduction:
The microvascular cerebral blood flow response (rCBF) to orthostatic stress has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS). However, its relevance to the outcome is unknown.

Hypothesis:
CBF response to head-of-the-bed (HOB) elevation within the first hours after AIS is related to outcome.

Methods:
Patients with a large anterior circulation stroke of less than 48h from the stroke onset were monitored with DCS to follow rCBF in the frontal lobes during a HOB elevation from supine to 30°. All patients were placed flat during the first 24 hours and later, mobilization was initiated depending on the clinical condition. We categorized measurements as early (<12h) or late (>12h) from stroke onset. NIHSS was recorded at baseline, during HOB, at 24h and 48h. The modified Rankin scale (mRS) score was utilized as the outcome measure (favorable when 0-2).

Results:
We studied 34 patients (age 78±13y, male 47%, median NIHSS 19 (14-21)) at 16±11 hours from stroke. Ipsilateral extracranial and/or intracranial occlusion was present in 61%. Frontal CBF decreased in both hemispheres after HOB (-5±14%). A paradoxical response (increase/no change) was observed in 18%. rCBF was not correlated to NIHSS and age. Unfavorable outcome was found in 85%. Only at early hours (<12h, n=16), rCBF to HOB elevation in the ipsilateral (not in contralateral) hemisphere (p=0.04, Figure 1) and NIHSS
HOB
(p=0.008) were associated with poor outcome.

Conclusions:
This result suggests that paradoxical CBF response to a mild HOB elevation in the early hours of stroke onset is associated with a poor outcome in patients with AIS. Optical continuous monitoring in the bedside may help to individualize management strategies in the early hours of AIS.

Figure 1: rCBF due to HOB elevation versus mRS for the ipsi-lateral side in patients measured <12h after stroke.
Abstract TMP95: Small Vessel Disease Burden and Clinical Symptoms in Cerebral Amyloid Angiopathy Patients Presenting Without Symptomatic Hemorrhage
Authors: Boulouis Gregoire , Charidimou Andreas , Jessel Michael J , Xiong Li , Roongpiboonsopit Duangnapa , Fotiadis Panagiotis , Pasi Marco , Ayres Alison , Merrill M. Emily , Schwab Kristin M , Rosand Jonathan , Gurol M. Edip , Greenberg Steven M , Viswanathan Anand
Published: June 2021

Introduction:
Cerebral amyloid angiopathy (CAA) is a common age-related small vessel disease (SVD). Patients without ICH typically present with transient focal neurological episodes (TFNEs) or cognitive symptoms. We sought to determine if SVD lesion burden differed between CAA patients first presenting with TFNEs versus cognitive symptoms.

Methods:
A total of 647 patients presenting either to a stroke department (n=205) or an outpatient memory clinic (n=442), were screened for eligibility. Patients meeting modified Boston criteria for probable CAA were included and markers of SVD were quantified including cerebral microbleeds (CMBs), perivascular spaces, cortical superficial siderosis (cSS), and white matter hyperintensities (WMH). Patients were classified according to presentation symptoms (TFNEs vs cognitive). Total CAA-SVD burden was assessed using a validated summary score. Individual neuroimaging markers and total SVD burden were compared between groups using univariable and multivariable models.

Results:
There were 261 probable CAA patients included. After adjustment for confounders, patients first seen for TFNEs (n=97) demonstrated a higher prevalence of cSS (p<.0001), higher WMH volumes (p=0.03) and a trend towards higher CMBs counts (p=.09). The total SVD summary score was higher in patients seen for TFNEs (adjusted OR per additional score point=1.46, 95%CI [1.16 - 1.84], p=0.013).

Conclusion:
We present a large cohort of probable CAA patients without ICH and show that those first evaluated for TFNEs bear a higher burden of structural MRI SVD related damage compared to those first seen for cognitive symptoms. This study sheds light on CAA disease phenotypes, adds to the understanding of CAA clinical expression, and sets the basis for future works investigating CAA prognosis amongst phenotypes.
Abstract TMP97: Demyelination, Cognition and Imaging in a Translational Model of Rat Vascular Cognitive Impairment
Authors: Nath Manan , Wagshul Mark E , Ferbinteanu Janina , Rosenbaum Daniel M , Selvan Pradeep , Anyanwu Chidinma , Li Jie , Barone Frank C
Published: June 2021

Small vessel disease and/or atherosclerosis produce microvascular and parenchymal inflammation in white matter and results in vascular cognitive impairment (VCI). We have performed bilateral carotid artery stenosis in hypertensive rats (SHR) to better understand disease pathology, targets for intervention and markers.

Hypothesis:
Complex cognitive deficits and diffuse fiber tract changes relevant to human VCI can be quantified and validated for future use.

Methodology:
We performed a series of behavioral assays to test declarative memory and executive functioning in stenosis compared to sham surgery SHR. Behavioral assays included T-maze decision making and alternation, novel object recognition (NOR) and active place avoidance (APA). MRI (DTI, DWI, Arterial Spin Labeling; ASL) and FDG-PET imaging was done in Corpus Callosum (CC). Histology-immunohistochemistry included measurements of microglia (Iba-1), astrocytes (GFAP) and Luxol fast blue (for myelin) in CC.

Results:
Stenosis resulted in consistent executive function decision making (T-maze) deficits (p<0.05) and impaired complex cognitive performance (APA). No significant differences occurred between sham and stenosis animals in NOR and T-maze alternation. DTI analysis indicated significant (p<0.05) changes in the CC of stenosis compared to sham SHR including: (1) decreased fractional anisotropy, (2) increased radial diffusivity, and (3) unchanged axial diffusivity. MRI ASL revealed significant (p<0.05) decreases in white matter perfusion. No significant changes were seen in FDG-PET. In summary, stenosis animals exhibited increased white matter glial cell inflammation related to demyelination and lost cognition. The inflammatory microglia phenotype was verified using TNFα plus Iba-1 double staining. CC changes were significantly (p<0.05) greater in the anterior, periventricular forebrain.

Conclusion:
We have successfully modeled the behavioral, imaging and histologic profile of human VCI in the rat. Currently pre/mature oligodendrocyte changes are being evaluated. This approach provides future opportunities to localize forebrain white matter changes using MR imaging parameters as markers for monitoring VCI demyelination/pathology and intervention.
Abstract TP100: Pharmacological Inhibition of ACC1 Restrains Peripheral T Cell Activation and Protects Against Cerebral Ischemic Stroke
Authors: Li Peiying , Wang Long , Zhou Yuxi , Wang Xing , Yu Weifeng
Published: June 2021

Background and purpose:
T cell activation, which is detrimental to the ischemic brain, requires metabolic reprogramming to meet the increased fuel demanding. ACC1 is an enzyme catalyzing the carboxylation of acetyl-CoA to malonyl CoA, a key substrate in the glycolytic-lipogenic pathway, which is extremely critical for T cell differentiation and phenotype polarization. We tested the hypothesis that pharmacologically inhibiting the enzyme ACC1 early after stroke may restrain T cell activation and protect against cerebral ischemic injury.

Methods:
Cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 60 minutes in C57/B6 mice. Soraphen A, the specific pharmacological inhibitor of ACC1 was administered at 1 hour after reperfusion at the dose of 1mg/kg, 5mg/kg, 10mg/kg and 50mg/kg intraperitoneally. Infarct volume was assess at 3 days after surgery by staining with 2,3,5-triphenyltetrazolium chloride. Behavior assessments, such as body proprioception, climbing, forelimb walking, lateral turning, foot fault and adhesive removal were examined at 3, 5, 7, 14, 21 and 28 days after stroke. T cell infiltration into the ischemic brain was examined by immunofluorescent staining.

Results:
Mice treated with 5mg/kg or 10mg/kg soraphen A exhibited significantly smaller infarct volume at 3 days after stroke. 5mg/kg was chosen as the dose for further experiments. Soraphen A treatment improved the overall neurological assessment and enhanced the performance of mice in adhesive removal test and grid walking test. Soraphen A treatment significantly attenuated the CD3+ T cell and Gr-1+ neutrophil infiltration in the ischemic mice brain at 3 days after surgery.

Conclusion:
Pharmacological inhibition of T cell activation by soraphen A is protective against cerebral ischemic injury and may represent a novel strategy for stroke therapy.
Abstract TP101: Intra-arterial IL-1α is Well Tolerated and Neuroprotective After Experimental Ischemic Stroke
Authors: Salmeron Kathleen E , Maniskas Michael E , Trout Amanda , Pinteaux Emmanuel , Fraser Justin F , Bix Gregory J
Published: June 2021

Endovascular thrombectomy and t-PA are the only current standard of care treatments for emergent large vessel occlusion (ELVO) stroke. Despite rising recanalization rates, stroke remains the leading cause of long-term disability worldwide suggesting that additional therapies are needed. Severe stroke morbidity may be due, in part, to the acute and sustained inflammatory stroke response. Preclinical research has supported anti-inflammatory agents in limiting brain injury and improving functional outcome; however, the post-stroke inflammatory cascade appears to have both beneficial and deleterious effects, necessitating careful therapeutic translation. We have recently demonstrated that delayed (3 day) post-stroke intravenous (IV) administration of the interleukin (IL)-1α (one of the two major isoforms of the pro-inflammatory family of cytokine IL-1), promoted, rather than suppressed, post-stroke angiogenesis in the transient middle cerebral artery occlusion (MCAo) mouse model. In this study, we aimed to show a therapeutic efficacy of IL-1α in neuroprotection. We investigated the potential for IL-1α, administered acutely IV or intra-arterial (IA) (n=5) after mouse MCAo, to also be neuroprotective. We noted that IV IL-1α (1 ng) is neuroprotective (as measured by cresyl violet stained infarct volumes) with mild, transient side effects (blunted hypertension and bradycardia) that were well tolerated, and with better functional recovery in free motion behavioral tests. IA IL-1α (0.1 ng) administration was even more neuroprotective without the systemic changes seen with IV treatment. Additionally, we noted that IL-1α is directly neuroprotective of primary mouse cortical neurons exposed to oxygen and glucose deprivation conditions
in vitro
. Taken together, these results suggest that IL-1α could be therapeutic after stroke when administered IV or IA, and the latter may eliminate potentially harmful hemodynamic side effects.
Abstract TP103: Liraglutide Reduces Amyloid-β Deposits and Secondary Damage in the Thalamus After Focal Cortical Infarction in Rats
Authors: Xu Anding , Zhu Huili , Zhang Yusheng
Published: June 2021

Introduction:
Focal cerebral cortical infarction causes β-amyloid (Aβ) deposition and secondary neuronal degeneration in the ipsilateral thalamus. The present study aimed to investigate the protective effects of liraglutide, a long-acting glucagon-like peptide-1 (GLP-1) analogue, on Aβ deposits and secondary neuron damage in thalamus after cerebral infarction.

Methods:
Sixteen male Sprague-Dawley rats were subjected to distal middle cerebral artery occlusion (MCAO) and then randomly divided into liraglutide and vehicle groups and 8 sham-operated rats as control. At 1 hour after MCAO, rats were subcutaneously injected with liraglutide (100 μg/kg/d) and isopyknic vehicle, respectively, then continuously injected once a day for 7 days. Sensory function and secondary thalamic damage were assessed with adhesive-removal test, Nissl staining and immunostaining. Terminal-deoxynucleotidyl transferase-mediated nick end labelling (TUNEL) staining and Western blot were employed to detect the neuronal apoptosis at 7 days after MCAO.

Results:
At 7 days after MCAO, liraglutide decreased the mean time of adhesive-removal at left forepaw compared with the vehicle group (P < 0.05). Treatment with liraglutide reduced Aβ deposition compared with that in the vehicle group (P < 0.05). The number of intact neurons in the ipsilateral thalamus was decreased compared with the control group at 7 days post-MCAO, liraglutide significantly improved the number of intact neurons compared with the vehicle group (P < 0.05). Liraglutide decreased the glial fibrillary acidic protein (GFAP)-positive area and the number of ionized calcium bindingadaptor molecule-1 (Iba-1)-positive cells in the ipsilateral thalamus compared with the vehicle group (P < 0.05). Liraglutide significantly decreased the number of TUNEL-positive neurons in the ipsilateral thalamus compared with the vehicle group (P < 0.05). Consistent with the TUNEL staining results, liraglutide increased the ratio of Bcl-2/Bax (P < 0.05) and decreased the expression level of cleaved Caspase-3 relative to the vehicle group (P < 0.05).

Conclusions:
Liraglutide reduces Aβ deposits in the ipsilateral thalamus, improves

the secondary thalamic damage and neurological deficit after cerebral infarction.
Abstract TP115: Cerebral Hemodynamic Changes in Military Personnel With Long-term Effects of Concussions
Authors: Razumovsky Alexander , Rampino Melissa , Kouperberg Efim , Neuges Donna M , DeGraba Thomas J , DeGraba Thomas J
Published: June 2021

Service members (SMs) suffer from repeated exposure to concussions or mild TBI, which can disrupt cerebral blood flow. This effect is seen in the acute phase of TBI, but the development of vascular wall abnormalities, which can lead to luminal narrowing and abnormally elevated cerebral blood flow velocities (CBFV), has not been studied in the post concussive phase. The purpose of this study was to evaluate the transcranial Doppler (TCD) determined incidence of abnormal cerebral hemodynamics in patients with long-term effects of mTBI.

Material and Methods:
TCD recordings of mean CBFV in cm/sec and Pulsatility Indices (PI) were recorded from 431 SMs (9 females; ages 24-54, mean age 39.2 ± 6.4 years) who were admitted to the National Intrepid Center of Excellence 4-week Interdisciplinary Outpatient Program. TCD data were analyzed to determine whether SMs exhibited abnormal CBFV s in the middle cerebral artery, internal carotid artery (ICA), and basilar artery. All subjects consented to protocol #362504 prior to any data collection or analysis. Two standard deviation from the mean CBFV in any direction labeled as an abnormal and PI was assumed normal with values between 0.7 and 0.9 Patients with one or more vessels with abnormal CBFV’s and PI’s were labeled as abnormal.

Results:
Average time since last TBI was 5.1 ± 3.4 years. We observed abnormal CBFV values in 33% of SMs. 149 (35%) and 48 (11%) demonstrated abnormally high CBFV and PIs in one or more vessels, respectively. Abnormal CBFV was observed most frequently in the ICA (48%). Majority of studied patients had patchy pattern of abnormal data presented in one or few vessels. The presence of abnormal cerebral hemodynamics was inversely related to the time since the last mTBI exposure: the likelihood of abnormal CBFV values deceased with increasing time since last head injury was sustained but was still present.

Conclusions:
Our data reveal that a large proportion of SMs have elevated CBFVs following mTBI exposure in many years after last mTBI. We believe that head injuries due to combat and training blast and blunt force trauma exposure cause early atherosclerotic or fibrotic changes in the large vessel walls of the Circle of Willis, which results in vascular lumen narrowing and increased CBFV’s.
Abstract TP13: Procedural Time (Groin Puncture to Recanalization) Significantly Predicts Outcomes in Endovascular Treatment: A Pooled Analysis of SWIFT, STAR and SWIFT PRIME Trials
Authors: Hassan Ameer E , Saver Jeffrey L , Goyal Mayank , Liebeskind David S , Jahan Reza , Qureshi Adnan I
Published: June 2021

Background:
Recent single center studies have suggested that “procedural time” independent of “time to procedure” can affect outcomes of acute ischemic stroke patients undergoing endovascular treatment (ET). We performed a pooled analysis from three ET trials to determine the effect of procedural time on angiographic and clinical outcomes.

Objective:
To determine the relationship between procedural time and clinical outcomes among acute ischemic stroke patients undergoing successful recanalization with ET.

Methods:
We analyzed data from SWIFT, STAR and SWIFT PRIME trials. Baseline demographic and clinical characteristics, NIHSS score on admission, intracranial hemorrhage rates and mRS at 3 months post procedure were analyzed. TICI scale was used to grade post procedure angiographic recanalization. Procedural time was defined by the time interval between groin puncture and recanalization. We estimated the procedural time after which favorable clinical outcome was unlikely even after recanalization (futile) after age and NIHSS score adjustment.

Results:
We analyzed 301 patients who underwent ET and had near complete or complete recanalization (TICI 2b or 3). The procedural time (±SD) was significantly shorter in patients who achieved a favorable outcome (mRS 0-2) compared with those who did not achieve favorable outcome (44±25 vs 51±33 minutes, p=0.04). Table 1. In the multivariate analysis (including all baseline characteristics with a p value <0.05 as independent variables), shorter procedural time was a significant predictor of lower odds of unfavorable outcome (OR 0.49, 95% CI 0.28, 0.85, p=0.012). The rates of favorable outcomes were significantly higher when the procedural time was <60 minutes compared with ≥60 minutes (62% vs 45%, p=0.020).

Conclusion:
Procedural time in patients undergoing mechanical thrombectomy for acute ischemic stroke is an important determinant of favorable outcomes in those with near complete or complete recanalization.
Abstract TP134: Carotid Endarterectomy for Symptomatic Low-grade Stenosis Refractory to Medical Treatment
Authors: Yoshida Kazumichi
Published: June 2021

Background and purpose:
Several large multicenter trials have demonstrated that carotid endarterectomy (CEA) benefits patients with symptomatic moderate-to-high-grade carotid stenosis (CS), but not those with low-grade CS. Accumulating evidence from vascular biology studies indicates that plaque stability in addition to stenosis rate considerably impacts risk for ischemic events. The present study aimed to determine the characteristics of symptomatic low-grade CS that was refractory to medical treatment and confirm the safety and efficacy of CEA.

Methods:
We studied 61 (male, n = 54; mean age, 71.0 ± 6.5 years) consecutive patients with symptomatic CS who underwent CEA. The patients’ characteristics, preoperative carotid MRI plaque imaging findings, and short- and long-term outcomes after CEA were compared between those with low-grade CS (< 50%, n = 17) and those with moderate-to-high grade CS (≥ 50%, n = 44). Plaque excised from patients with low-grade CS was also histologically assessed. We considered CEA to treat low-grade CS when recurrence was refractory to aggressive medical approaches.

Results:
The characteristics did not significantly differ between patients with low-grade and moderate-to-high-grade CS. The degree to which MRI detected intraplaque hemorrhage was significantly higher (P = 0.04) and the extent of expansive arterial remodeling tended to be higher (P = 0.18) in patients with low-grade CS. Intraplaque hemorrhage was confirmed in all 17 excised plaques from patients with low-grade CS and in 15 ruptured fibrous caps and two erosions. Short-term outcomes, including the rate of internal shunt deployment under selective use based on intraoperative monitoring and new ischemic lesions after CEA on postoperative diffusion weighted images, as well as long term outcomes did not significantly differ between the groups.

Conclusions:
CEA was safe and effective for symptomatic low-grade CS that was refractory to aggressive medical treatment. Plaque characterization by MRI has the potential to provide more accurate stroke risk stratification for the management of low-grade CS.
Abstract TP140: Very Early Mobilization In Critically Ill Stroke Patients With Primary Intracerebral Hemorrhage
Authors: Bahouth Mona N , Power Melinda , Zink Elizabeth , Kumble Sowmya , Deluzio Sandra , Urrutia Victor , Stevens Robert
Published: June 2021

Background:
Spontaneous intracerebral hemorrhage (ICH) is associated with a disproportionately high mortality and disability when compared to ischemic stroke. Critically ill patients with ICH represent a specific challenge due to issues of intracranial pressure and hemodynamic instability in the early period post stroke. The aim of this study was to evaluate the effect of a progressive mobility algorithm, a structured tool used to guide mobilization of all patients in the neuroscience critical care unit (NCCU), on the time elapsed to earliest mobility activities in patients with primary ICH.

Methods:
We used a quasi-experimental design to examine current mobility practices for patients with ICH after rollout of the mobility algorithm in our NCCU. The Johns Hopkins Mobility algorithm was developed by an interdisciplinary mobility team and stratifies NCCU patients to progressive passive or active mobilization programs. Baseline data were collected retrospectively from electronic medical records for two 6 month periods, one before and one after program implementation. Time of first mobilization and frequency of mobilization were reported for baseline and post intervention comparison and adjusted based on patient characteristics.

Results:
Two groups of ICH patients (pre- rollout, n=28; post-rollout, n=29) were similar on baseline characteristics, with the exception of mean ICH severity scores which were greater in the post-rollout group (p=0.07). Patients in the post-intervention group were significantly more likely to be mobilized within the first 7 days after admission (55% versus 29% in the pre and post intervention groups respectively, p=0.04), No episodes of hypotension, falls or line dislodgements were reported in association with the early mobility intervention.

Conclusions:
Use of a progressive mobility algorithm in stroke patients with spontaneous ICH increases the percentage of patients who are mobilized in the early critical period without issues of safety. Additional work in larger prospective cohorts is needed to evaluate the reasons for delay of mobilization on day one of hospitalization and to enhance data support for best practice timing recommendations.
Abstract TP16: Short-Term Thrombectomy Outcomes Beyond the Traditional 6-Hour Time Window: Analysis of a Multi-Hub Telestroke Network
Authors: Bhatt Archit , Lucas Lindsay , Baraban Elizabeth
Published: June 2021

Background/Purpose:
Acute ischemic stroke patients with large vessel occlusions are traditionally treated with thrombectomy within a 6-hour time window. Often patients get groin punctures for thrombectomy beyond 6 hours. The purpose of our study is to report real world data comparing short-term outcome differences in patients who receive groin punctures within 6 hours versus beyond 6 hours in a multi-hub telestroke network.

Method:
Data obtained from the Providence Health and Services Get With the Guidelines stroke registry were used to identify AIS patients who received intra-arterial (IA) intervention and were discharged from the hospital between November 2014 and May 2016. Patients were categorized as having Last Known Well-to-Groin-Puncture times (LKW-to-GP) over six hours or LKW-to-GP below or equal to six hours. Outcomes were modified rankin score (mRS) at discharge (slight or no disability versus moderate disability to dead), discharge disposition (home versus not home), change in NIHSS from admittance to discharge, and length of stay (LOS). Multivariate analyses were used to determine impact of the LKW-to-GP group on outcomes adjusting for post thrombolysis in cerebral infarction (TICI) grade, pre-symptom onset mRS, and admission NIHSS score. Intracranial hemorrhage rates were compared between the two groups using Fisher’s exact test.

Results:
We identified 136 ischemic stroke patients, 46.3% female with a mean age of 70.7 years (±14.6), who received IA intervention and were discharged between November 2014 and May 2016. Of those, 21% (n=29) had LKW-to-GP below or equal to six hours and 79% (n=107) had LKW-to-GP above six hours. After adjusting for covariates, there were no statistically significant differences in discharge mRS (p=.284), discharge disposition (p=.736), length of stay (p=.473) and change in NIHSS (p=.135). Unadjusted intracranial hemorrhage rates (p=.101) between the two LKW-to-GP groups were also not significant.

Conclusions:
We discovered one in five patients were treated beyond the traditional time window in a multi-hub telestroke network. We found no statistically significant difference in short term outcomes in patients receiving thrombectomy beyond 6 hours compared to those receiving thrombectomy within 6 hours.
Abstract TP161: Low Free Triiodothyronine on Admission Should Be Associated With Post-stroke Infection in Acute Stroke Patients
Authors: Suda Satoshi , Shimoyama Takashi , Takayama Yohei , Ouchi Takahiro , Arakawa Masafumi , Suzuki Shizuka , Okubo Seiji , Aoki Junya , Suzuki Kentaro , Mishina Masahiro , Kimura Kazumi
Published: June 2021

Background and purpose:
Post-stroke infection (PSI) is a common and it is associated with a severe prognosis. Recent studies have shown that thyroid hormones play critical roles in the immune system regulation. However, association between PSI and thyroid hormone have not been fully elucidated. We therefore investigated the impact of thyroid hormone on PSI in acute stroke patients.

Methods:
We retrospectively enrolled 520 consecutive patients with acute ischemic stroke (326 male, 71.9 ± 13.2 years) admitted to our department between September 2014 and June 2016. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were evaluated upon admission. PSI was defined as infection occurring during hospitalization. The impact of the thyroid hormone on PSI was evaluated using multiple logistic regression analysis. Separate analyses were conducted according to PSI and quartile serum FT3 concentration.

Results:
PSI was diagnosed in 107 patients (20.6 %). The most common infection was pneumonia with the prevalence of 65 patients (60.7 %), followed by urinary tract infection recorded in 19 patients (17.8 %). Age (
P
< 0.001), body mass index (
P
= 0.0044), pre-admission mRS (
P
= 0.002), NIHSS score on admission (
P
< 0.001), admission FT3 (2.63 ± 0.49 pg/mL vs. 2.24 ± 0.66 pg/mL,
P
< 0.001), and cardio-embolic stroke (
P
< 0.001) were significantly associated with PSI, but no relationship between TSH (2.84 ± 8.12 mIU/L vs. 2.20 ± 1.45 mIU/L,
P
= 0.4610), FT4 (1.22 ± 0.21 ng/dL vs. 1.21 ± 0.28 ng/dL,
P
= 0.1478), and PSI were found. On multivariable logistic regression analysis, low FT3 (< 2.29 pg/mL; odds ratio [OR], 2.96; 95% confidence interval [CI], 1.61- 5.45;
P
= 0.0005) and high admission NIHSS score (≥ 9 points, OR, 7.65; 95% CI, 4.10-14.73;
P
<0.0001) were independently associated with PSI. In comparisons between PSI and FT3 quartiles (Q1 [≤ 2.25 pg/mL], Q2 [2.26-2.55 pg/mL], Q3 [2.56-2.89 pg/mL], Q4 [≥ 2.90 pg/mL]), patients with PSI were significantly more frequent in Q1 than in Q2, Q3, and Q4 after multivariate adjustment.

Conclusions:
Our results showed that a low FT3 at admission should be associated with PSI in acute ischemic stroke patients.
Abstract TP162: Specific Inflammatory Mediators Associated With Incident Ischemic Stroke and Individual Ischemic Stroke Subtypes
Authors: Sen Souvik , Offenbacher Steven , Moss Kevin , Giamberardino Lauren D , Rosamond Wayne
Published: June 2021

Introduction:
Epidemiological studies have shown that serum inflammatory markers are independently associated with ischemic stroke. We assessed the hypothesis that specific inflammatory mediator is associated with specific ischemic stroke subtypes in the Atherosclerosis Risk in Communities (ARIC) study.

Methods:
In the ARIC study, serum inflammatory mediators were assessed in a cohort of subjects without prior stroke. They included high sensitivity C-reactive protein (hs-CRP), interleukin 1ra (IL-1ra), and Intercellular Adhesion Molecule 1(sICAM1) and were followed for all vascular events. All stroke events were adjudicated and classified into stroke subtypes by standard definitions. Multivariable Cox proportional hazards models were used to study the relationship between elevated inflammatory markers (upper quartile compared with lower three quartiles) and ischemic stroke, as well as stroke subtypes (cardioembolic, lacunar or thrombotic).

Results:
At the fourth ARIC study visit, serum inflammatory mediators were assessed in a cohort of 5663 subjects (mean age±SD=62.3±5.6, 55% female, 83% white and 17% African-American). Over a 15-year follow-up, 237 (4.2%) subjects had incident ischemic stroke of which 47% were thrombotic, 26% were cardioembolic, and 20% were of the lacunar stroke subtype. After adjustment for Race/Center, Age, Gender, BMI, Hypertension, Diabetes, LDL Level, Smoking (3-levels), Pack Years, Education (3-levels), hs-CRP (adjusted HR 1.45, 95% CI 1.08-1.96), IL-1ra (adjusted HR 1.90, 95% CI 1.09-3.28) and sICAM1(adjusted HR 1.33, 95% CI 1.0-1.78) were associated with overall ischemic stroke. This was driven by associations between hs-CRP and thrombotic stroke (adjusted HR 1.73, 95% CI 1.14-2.61), IL-1ra and cardioembolic stroke (adjusted HR 3.42, 95% CI 1.23-9.53), and sICAM-1 and lacunar stroke (adjusted HR 1.92, 95% CI 1.05-3.50).

Conclusions:
Results from this prospective show an independent association between serum inflammatory mediators and incident ischemic stroke. These associations appear to be attributed to the association between specific inflammatory mediator and individual stroke subtype. These results shed light to the mechanism by which inflammatory mediators contribute to stroke risk.
Abstract TP164: Blood Pressure and Heart Rate Measures and Risk of Covert Brain Infarction and Worsening White Matter in Older Adults
Authors: Leung Lester Y , Bartz Traci M , Rice Kenneth , Floyd James , Psaty Bruce , Gutierrez Jose , Longstreth Will , Mukamal Kenneth J
Published: June 2021

Introduction:
Covert brain infarction (CBI) and worsening white matter grade (WMG) on serial MRI are associated with increased risk for ischemic stroke and dementia.

Hypothesis:
We sought to evaluate the association of various measures of blood pressure and heart rate with these MRI findings.

Methods:
In the Cardiovascular Health Study, a longitudinal cohort study of cardiovascular disease in older adults, we used relative risk regression to assess the risk of incident CBI and worsening WMG associated with mean, variability, and trend in systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) measured at four or more annual clinic visits between two brain MRIs. We included participants who underwent both brain MRIs and had no change in antihypertensive medication status, no CBI on the initial MRI, and no stroke before the follow-up MRI.

Results:
Among 897 eligible participants, incident CBI occurred in 15% and worsening WMG in 27%. Mean SBP mean was strongly associated with increased risk for incident CBI (RR per 10 mmHg 1.29; 95% CI, 1.13-1.47), and DBP mean was strongly associated with increased risk for worsening WMG (RR per 10 mmHg 1.43; 95% CI, 1.23-1.67). DBP variability may be associated with incident CBI (RR per 10 mmHg 1.71; 95% CI, 1.10-2.65), The HR measures were not associated with these MRI findings.

Conclusions:
Elevated mean levels of blood pressure contribute to covert cerebrovascular diseases. Control of mean blood pressure levels, even in older adults, remains a high priority for prevention of vascular brain injury.
Abstract TP17: Patients Treated With Endovascular Treatment Outside Guidelines
Authors: Simonsen Claus Z , Rasmussen Mads , Yoo Albert J , Sørensen Leif H
Published: June 2021

Backgroud:
The number of Endovascular treatments (EVT) in stroke is increasing rapidly after the publication of the positive trials. Generally, EVT is recommended in anterior circulation large vessel stroke in a 6 hour time window in patients who are independent (modified Rankin scale 2 or less) and if the infarct is not too large (ASPECTS > 4 or diffusion weighted imaging lesion volume <70 cc).

Methods:
GOLIATH (General Or Local anesthesia in Intra Arterial THerapy) is a study which is testing whether conscious sedation (CS) or general anesthesia (GA) should be recommended during EVT. The inclusion criteria for GOLIATH include those mentioned above and also, patients must have an MRI scan because the primary outcome measure is infarct growth from baseline to 48-72 hours after EVT as measured on diffusion weighted imaging. Included patients are randomized between GA and CS. We have also captured screen failures (i.e., patients who did not fulfil inclusion criteria but who underwent EVT anyway). We compared the number of patients treated in GOLIATH with the number of screen failures from study initiation in March 2015 to August 2016.

Results:
Eighty-seven patients have been enrolled in GOLIATH. In the same period, 85 patients have been treated with EVT outside of GOLIATH. The reasons for screen failure were: Posterior circulation stroke: 20 patients NIHSS <10: 18 patients Groin puncture > 6 hours: 16 patients CT scan: 16 patients. (Pacemaker, vomiting, metallic foreign bodies or implants) Intubated at arrival: 5 patients Infarct > 70 cc: 3 patients Baseline mRS >2: 2 patients Age <18 years: 2 patients Withdrew consent: 1 patient Deemed unsafe by anesthesiologist: 2 patients

Discussion:
Among the first 69 patients in GOLIATH, 45 (65%) achieved a good outcome and 6 (9%) were dead at 90 days. Among the first 58 screen failures, 21 (36%) achieved a good outcome and 16 (28%) were dead at 90 days (p=0.002 for good outcome and p=0.01 for death, Chi-square test).

Conclusion:
A high number of patients are treated outside the general guidelines. Trials are needed to demonstrate effect is these subgroups. (Posterior circulation stroke, NIHSS <10 and groin puncture >6 hours.)
Abstract TP172: Pulmonary Function and White Matter Hyperintensity in Neurologically Healthy Adults
Authors: Jeong Han-Yeong , Park Jin Ho , Kwon Hyung-Min
Published: June 2021

Introduction:
Cerebral small vessel disease (SVD) is considered as precursor lesion of many clinical outcomes including stroke and dementia. It is well established that obstructive sleep apnea or chronic obstructive pulmonary disease is an independent risk factor of stroke. However, there are few studies about the association between pulmonary function and the presence of cerebral small vessel disease.

Purpose:
This study aims to investigate the association between pulmonary function and cerebral SVD in healthy adults.

Methods:
We conducted a cross-sectional study of 1,528 neurologically healthy people (mean age 56.0±9.0; 847 men), who underwent brain MRI and pulmonary function tests (forced vital capacity (FVC), forced expiratory volume in the first second (FEV
1
)). Risk factors, anthropometric parameters and clinical information were obtained. For evaluating cerebral SVD, the presence of small silent infarction (SSI) and the volume of white matter hyperintensity (WMH) were assessed through axial T2 fluid-attenuated inversion recovery (FLAIR) sequences MRI. Cerebral microbleeds (CMBs) were evaluated through T2-weighted gradient-recalled echo MRI.

Results:
The prevalence of SSI and CMBs were 9.6% (147 subjects) and 4.1% (63 subjects), respectively. The mean volume of WMH was 2.8±6.2mm
3
. In multiple regression analysis that controlled for age, sex, and smoking status, FVC had a significant negative correlation with WMH volume (R
2
=0.005, β=-0.109, p=0.002), and FEV
1
/FVC ratio had a significant correlation with WMH volume (R
2
=0.006, β=0.083, p=<0.001). In multivariable logistic analysis, after adjusting age, gender, hypertension, and glucose, FVC was negatively associated with the presence of SSI (adjusted OR 0.63, 95% CI 0.44-0.91), and FEV
1
/FVC ratio was positively associated with the presence of SSI (adjusted OR 1.05, 95% CI 1.02-1.08). The presence of CMBs was not associated with any factor of pulmonary function tests.

Conclusions:
The results from our study suggest that lower pulmonary function, especially FVC, was found to be an independent risk factor of cerebral SVD in neurologically healthy adults.