bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP38: Early Progressive Ischemia Predicts Worse Clinical Outcome In Acute Ischemic Stroke and Is Decreased With tPA Treatment
Authors: Ford Andria L , An Hongyu , Vo Katie D , Powers William J , Lin Weili , Lee Jin-Moo
Published: July 2021

Background:
While some ischemic stroke patients improve rapidly after onset, many show no improvement or even worsening in the first days after stroke. We hypothesized that development of brain regions with “progressive ischemia” within hours of stroke onset may predict poor clinical outcome.

Methods:
Acute ischemic stroke patients underwent two MR scans: within 4.5 hrs (tp1) and at 6 hrs (tp2) after onset. Mean transit time (MTT) maps measured tp1 and tp2 perfusion deficits. “Perfusion deficit” was defined as MTT > 6 s longer than the contralateral median. Volume of progressive ischemia (V
PR
) was defined by regions of normal perfusion (MTT<6) at tp1 which became abnormal (MTT>6) at tp2. Bivariate analyses between V
PR
and ΔNIHSS from admission to 1 month, V
PR
and 1 month mRS, and V
PR
and 1 month mortality were performed. Multivariable regression identified if V
PR
predicted ΔNIHSS, mRS, and mortality after adjusting for admission NIHSS, volume of reperfusion (V
rep
), and volume of tp1 perfusion deficit (V
tp1
). Regression analysis determined if tPA treatment predicted V
PR
after adjusting for admission NIHSS and V
tp1
.

Results:
Fifty patients were scanned at 2.9 (tp1) and 6.4 hrs (tp2) after onset. Mean NIHSS=14; 74% received IV tPA. Progressive ischemia was found in 34 (68%) patients (Fig. shows patient example). Mean V
tp1
, V
rep
, and V
PR
were 50, 14.4, and 6.4ml, respectively. V
PR
correlated with ΔNIHSS (r=-.25, p=0.096), mRS (r=.44, p=0.002), and mortality (r=.31, p=0.034). In multivariable analysis, V
PR
predicted less improvement in ΔNIHSS (β=-.19, p=0.019) and greater disability on mRS (β=0.06, p=0.016). In multivariable analysis, tPA treatment negatively predicted V
PR
(β=-3.6, p=0.050).

Conclusion:
Progressive ischemia, identified in 2/3 of our cohort, predicted worse outcomes. As tPA treatment predicted less progressive ischemia, therapies aimed at preventing progressive ischemia in acute ischemic stroke may be considered in addition to promoting reperfusion.
Abstract WP383: An Economic Model of Improved Acute Stroke Care in the Management of Acute Ischemic Stroke From A State Medicaid Perspective
Authors: Zhou Zheng-Yi , Fan Liangyi , Chen Er , Xie Jipan , Wu Eric Q
Published: July 2021

Background:
Stroke is a leading cause of long-term disability in the United States. Approximately one in four stroke survivors is admitted to a nursing home, accounting for a significant portion of Medicaid spending on stroke.

Objective:
To assess the impact of increasing access to primary stroke centers (PSCs) and implementing an emergency medical services (EMS) system on disability and Medicaid spending on nursing homes for ten geographically representative states.

Methods:
An economic model was developed to estimate potential reductions in stroke-related disability and corresponding reductions in Medicaid spending on nursing homes among Medicaid enrollees with acute ischemic stroke (AIS), due to improved stroke care infrastructure. The model assessed the increased use of intravenous (IV) thrombolysis as a result of a higher proportion of AIS treated in PSCs, or as a result of integrating an EMS system with PSCs. Based on published literature, more patients received IV thrombolysis in PSCs vs. non-PSCs (6.5 vs. 0.9%) and PSCs with an EMS routing protocol vs local services (10.5 vs. 2.5%). State-specific model inputs included the incidence of first-ever AIS in Medicaid enrollees, nursing home costs, and Medicaid spending on stroke-related care.

Results:
A 20% absolute increase in the proportion of AIS patients treated at PSCs will lead to 111 to 2004 more patients receiving IV thrombolysis; 9 to 160 fewer patients with disability; and a reduction in Medicaid nursing home spending of $299,442 to $5.6 million per year across the ten states analyzed (Table). The integration of an EMS system with PSCs will lead to 791 to 14,314 more patients receiving IV thrombolysis; 63 to 1145 fewer patients with disability; and a reduction in Medicaid nursing home spending of $2.1 to $40.0 million per year across the ten states (Table).

Conclusions:
States may achieve substantial savings through legislative policies that improve PSC access and integration of an EMS system with PSCs.
Abstract WP386: Improving Statewide Stroke Systems of Care in Times of Fiscal Challenge - the Results of Effective Partnership
Authors: Solenski Nina J , Agola John C , Hillman Diane G
Published: July 2021

Backgrd:
Stroke has afflicted ~7 M Americans. Total cost is ~ $43B per year. Treatment is poorly accessed due to geopolitical and resource challenges especially at Critical Access Hospitals. The Affordable Care Act of 2010, will ensure more Americans have access. Are stroke state systems of care adequately prepared to provide high quality care, and if so at what cost?

Object/Meth:
To develop an equitable statewide stroke system of care based on ASA-BAC guidelines, by executing an inclusive, legislative-supported Stroke System Task Force. The VSSTF was sanctioned in 2007 by the Va Joint Comm. of Healthcare; 30+ voluntary members were selected to represent each part of the continuum of care. Key stakeholders included experts from health insurance, pharma, hospital administration, with regional representation; meetings were held quarterly. Key partners included VDH, ASA, all major academic institutions, Va Hospital & Healthcare Assoc. All inpatient stroke data from pre and post VSSTF activities (2007-11) were analyzed by a Public Health consultant (DH) using a CMS required database (Va Health Information).

Results:
From 2007-11, the number of PSCs increased ~500% (7 to 34), with 1 PSC for every ~230K people (7/52 state ranking). There was a 50% increase in use of t-PA in admitted patients. Telestroke existed in 1 hospital in 2007, and in 18 hospitals in 2011. ~28% of patients were treated in a PSC in ’07, compared to 70% in ‘11. LOS fell by 1 day; the avg charge/case increased by 23%. Total ischemic stroke charges grew by 73%. Inpatient mortality was flat with a 75% increase in hospice transfers.

Conclusions:
There was a correlation between establishing a well-partnered, regionally diverse Stroke Task Force, and increased number of PSCs, higher % of pts treated at a PSC, more cases of acute TPA tx, and gowth of telestroke. External system changes, including better CMS reimbursement for TPA (2006); state legislation for reimbursement of telemedicine (2010) and EMS preferential triage to PSCs (VSSTF advocated), were also critical. Charges for care also significantly increased. The future challenge will be restraining costs as stroke cases increase, and aggressively advocating for prevention by expanding partnerships with cardiac, diabetes, home care state stakeholders.
Abstract WP400: Greater Stroke Severity Predominates Over All Other Factors For The Worse Outcome Of Cardioembolic Stroke
Authors: Hong Keun-Sik , Lee Juneyoung , Bae Hee-Joon , Lee Ji Sung , Kang Dong-Wha , You Kyung-Ho , Han Moon-Ku , Cho Yong-Jin , Song Pamela , Park Jong-Moo , Oh Mi-Sun , Koo Jaseong , Lee Byung-Chul
Published: July 2021

Background:
Cardioembolic (CE) strokes are more disabling and more fatal than non-CE strokes. Multiple prognostic factors have been recognized, but the magnitude of their relative contribution has not been well explored.

Methods:
Using a stroke outcome registry, we compared the outcomes of CE and non-CE strokes. The relative contribution of prognostic factors was assessed with multivariable models and model fitness improvement using -2 log-likelihood and Nagelkerke’s R
2
.

Results:
A total of 1233 patients were included in this analysis. As compared to non-CE strokes, CE strokes had less mRS 0-2 outcomes (47.2% vs 68.5%, p<0.001), less mRS 0-1 outcomes (33.7% vs 53.5%, p<0.001), more mRS 5-6 outcomes (32.1% vs 10.9%, p<0.001), and higher mortality (19.2% vs 5.2%, p<0.001). When adjusting either baseline demographics or poststroke complications, the outcome differences remained significant. However, adjusting initial NIHSS score alone abolished the differences in mRS 0-2 outcome (Figure) and mRS 0-1 and mRS 5-6 outcomes. For mRS 0-2 outcome, the differences in -2 log-likelihood and Nagelkerke’s R
2
between univariable model and multivariable model were greater with adjusting NIHSS alone (-2 log-likelihood difference, 418; Nagelkerke’s R
2
difference, 38.7%) than with adjusting baseline demographics (184; 17.7%) or poststroke complication (279; 27.3%). Further adjustment of baseline demographics and poststroke complication to the initial NIHSS score adjustment resulted in a small shift of odds ratio. The decrement of -2 log-likelihood and the Nagelkerke’s R
2
of the model adjusting initial NIHSS score alone approached 70.2% and 76.7% of the model adjusting baseline demographics, poststroke complication, and initial NIHSS score.

Conclusion:
Greater stroke severity predominates over all other factors for the worse outcome of CE stroke.
Abstract WP424: Efficacy Of Antiplatelet Therapy For Secondary Stroke Prevention Following Lacunar Stroke: A Meta-analysis And Pooled Analysis Of Randomized Controlled Trials
Authors: Shoamanesh Ashkan , Kwok Chun Shing , Myint Phyo K , Loke Yoon K , Copley Hannah , Benavente Oscar R
Published: July 2021

INTRODUCTION:
The predominant underlying mechanism of lacunar stroke differs from that of other ischemic stroke subtypes. Accordingly, so may the ideal stroke prevention regimen. We aimed to evaluate the efficacy of different antiplatelet agents in lacunar stroke patients.

Method:
We searched MEDLINE, EMBASE and the Cochrane library for RCTs that evaluated antiplatelet therapy in patients with ischemic stroke. Trials which provided stroke recurrence rates in patients presenting with lacunar stroke, or where the data was obtainable from manuscript authors were included. In addition, we included the novel SPS3 trial’s antiplatelet arm data presented at the 2011 ISC. We performed pooled analysis to assess the crude frequency of recurrent stroke and a random effects meta-analysis.

Results:
Lacunar stroke data was available for 12 trials encompassing 35, 218 participants (mean age 65, 65% male). The pooled crude recurrent stroke rate was least for cilostazol monotherapy (6.2%), followed by ASA monotherapy (7.4%), clopidogrel monotherapy (8.6%), ASA/dipyridamole (8.6%) and greatest for ASA/clopidogrel therapy (9.1%). Rate ratios of lacunar stroke patients suggest no significant efficacy advantage for ASA [ASA vs placebo (RR 0.72, 95% CI 0.34-1.50; p=0.38)], ASA/clopidogrel [ASA/clopidogrel vs ASA (RR 0.80, 95% CI 0.62-1.03; p=0.08), ASA/clopidogrel vs clopidogrel (RR 0.95, 95% CI 0.79-1.15; p=0.63)], sarpogrelate [sarpogrelate vs ASA (RR 1.31, 95% CI 0.84-2.04; p=0.23)] and ASA/dipyridamole [ASA/dipyridamole vs ASA (RR 0.90, 95% CI 0.70-1.16; p=0.042)] for recurrent stroke. The results from Japanese trials evaluating the efficacy of cilostazol found that it is significantly better than both placebo (RR 0.51, 95% CI 0.30-0.85; p=0.01) and ASA (RR 0.70, 95% CI 0.51-0.96; p=0.03) in the secondary prevention of stroke.

Conclusions:
There seems to be no significant advantage among the various antiplatelet agents studied in lacunar stroke patients apart for cilostazol. However, this requires confirmation within large randomized trials outside of Japanese populations.
Abstract WP428: Cardiopulmonary Response to Ischemic Stroke Varies by Stroke Location
Authors: Probasco John , Chang Tiffany , Victor David , Nyquist Paul
Published: July 2021

Introduction:
Ischemic stroke is associated with electrocardiographic and cardiac enzyme changes indicative of stunned myocardium. It is unknown if acute pulmonary edema occurs independent of cardiac dysfunction in ischemic stroke or in association with particular vascular distributions.

Hypothesis:
Ischemic strokes in the posterior fossa are associated with acute pulmonary edema independent of stroke related cardiac dysfunction.

Methods:
This is a retrospective study of ischemic stroke patients treated over two years at a tertiary medical center, including patients with basilar artery stroke (N=18), RMCA (N=31) and LMCA (N=27) distribution strokes involving the insula, and TIA controls (N=67). Of the 143 patients, 53% were female, 45% were black, 40% had a history of stroke or TIA, and 73% had hypertension. Discharge diagnosis, brain imaging, and review of chest x-rays (by two blinded reviewers) were used to determine the proportion of patients within each group with evidence of pulmonary edema. Cardiac variables including ejection fraction, serum troponin levels (>0.06 ng/mL), non-specific ST segment changes and QTc prolongation (>460ms) were compared between groups.

Results:
Patients with basilar artery occlusions and associated ischemic stroke developed pulmonary edema during their hospitalization more frequently than control patients (0.67 vs. 0.01, P<0.0001). There were no signs of stunned myocardium or CHF as indicated by elevated troponin, altered echocardiography, or QTc prolongation for the basilar group. None of the patients in the basilar group with pulmonary edema had altered echocardiography. Patients with RMCA and LMCA distribution strokes were noted to have a higher frequency of pulmonary edema compared to the controls (0.23, P=0.0012; 0.41, P=0.002), at a proportion less than the basilar group (for RMCA, P=0.005; LMCA, P=0.13,). The proportions of patients with elevated serum troponin and QTc prolongation were significantly greater for RMCA (0.41 vs. 0.05, P=0.0008; 0.40 vs.0.16, P=0.017) and LMCA (0.33 vs. 0.05, P=0.008; 0.36 vs. 0.16, P=0.046) patients relative to controls.

Conclusion:
Pulmonary edema occurs independently of cardiac stunning or dysfunction in patients with basilar artery occlusions.
Abstract WP431: Distinguishing RCVS-associated Subarachnoid Hemorrhage From Cryptogenic and Aneurysmal Subarachnoid Hemorrhage
Authors: Singhal Aneesh B , Kursun Oguzhan , Topcuoglu Mehmet A , Fok Joshua , Barton Bruce , Muehlschlegel Susanne
Published: July 2021

Background:
Reversible cerebral vasoconstriction syndrome (RCVS) is a self-limited entity with usually benign outcome. Over 30% RCVS patients develop subarachnoid hemorrhage (SAH). We aimed to identify features that differentiate RCVS-SAH from more ominous causes of SAH, i.e. aneurysmal SAH (aSAH) and cryptogenic ‘angio-negative’ SAH (cSAH).

Methods:
We compared the clinical-imaging features of 38 consecutive RCVS-SAH patients, to 515 aSAH and 93 cSAH patients consecutively admitted to Massachusetts General Hospital.

Results:
As compared to aSAH and cSAH, the RCVS-SAH group was significantly younger, more women, and higher frequency of migraine, depression, chronic obstructive pulmonary disease (COPD), alcohol and drug exposure, and prior antidepressant use. The distribution of Hunt-Hess (HH) grade and Fisher group were different between groups, with median values highest in the aSAH group. The RCVS-SAH group had more hypodense lesions on 1st head CT and earlier, more severe and widespread vasoconstriction on cerebral angiography. Discharge mRS scores were lowest in the RCVS-SAH group. To avoid overfitting, multivariate logistic regression (Firth’s method) was performed using separate models for clinical and radiological variables given small "N".
Predictors of RCVS-SAH vs. aSAH
[model 1]:
age (O.R. 0.9, 95% C.I. 0.9-0.96), prior headache disorder (O.R. 9.3, 95% C.I. 3.9-22.4), depression (O.R. 5.6, 95% C.I. 1.8-17.6), and COPD (O.R. 7.6, 95% C.I. 2.9-20.1), and
[model 2]:
HH grade (O.R. 0.4, 95% C.I. 0.2-0.7), Fisher group (O.R. 0.2, 95% C.I. 0.07-0.4), and the number of constricted arteries (O.R. 1.6, 95% C.I. 1.4-1.9).
Predictors of RCVS-SAH vs. cSAH
[model 1]:
age (O.R. 0.9, 95%C.I. 0.9-0.97), prior headache (O.R. 10.3, 95% C.I. 4.3-24.9), depression (O.R. 6.9, 95% C.I. 2.1-22.4), and alcohol use (O.R. 5.1, 95% C.I. 2.0-12.9), and
[model 2]:
Fisher group (O.R. 0.01, 95% C.I. 0.0-0.6), vasospasm severity (O.R. 9.1, 95% C.I. 1.4-57.2), and the number of constricted arteries (O.R. 2.0, 95% C.I. 1.2-3.1).

Conclusion:
Several clinical-imaging features distinguish RCVS-SAH from aSAH and cSAH. These data should prove useful to improve the diagnostic accuracy, management, and resource utilization in patients with SAH.
Abstract WP47: Flow Phantom for the Validation and Quantitative Analysis of Computed Tomography Perfusion
Authors: Seals Kevin , Wack David , Besch Steven , Fisher Jason , Creighton Terrance , Snyder Kenneth
Published: July 2021

Objective:
We create a flow phantom using a simple brain model with well-defined flow behavior. This allows for the validation of CT perfusion (CTP), as CTP data can be compared with theoretical calculations and gold standard flow meter values. Our approach offers a calibration system for existing CTP scanners, facilitating the selection of optimal data processing algorithms and parameter settings.

Methods:
The phantom was built using 37 parallel glass capillary tubes of internal diameter 1.0 mm fixed with epoxy. Saline was pumped into the inlet portion of a Y-shaped tubing system with one inlet and two outlets. One Y outlet led to the phantom, which was in series with a flow meter. The other outlet flowed to a waste container. A contrast bolus was introduced at the Y inlet and perfusion imaging was performed with a Toshiba 320 slice Aquilion One scanner. Phantom flow rates of 3, 5, 7.5 and 20 mL/min were used. Time activity curves (TACs) were calculated by averaging along various phantom segments.

Results:
CBV could be accurately recovered for all flow levels but 3 mL/min. MTT values were slightly higher than expected. Compared to TACs at the base of the Y, TACS just prior to the phantom showed significant dispersion. MTT measured across the phantom for length of 4.1 cm (i.e. internal volume 1 mL) with a flow meter rate of 20 mL/min was 0.066 min, whereas 0.05 min was expected. However, the same measurement for a flow of 3 mL/min had an MTT of 0.32 min, close to the expected value of 0.33 min.

Conclusions:
We have developed a robust system for the analysis of CTP. CBV was accurate provided sufficient scan duration. MTT values were mildly exaggerated due to dispersion of the contrast bolus. This is analogous to measuring an early arterial TAC, such as the carotid TAC, when tissue segments are fed by smaller branches. This dispersion causes a lower bound for MTT, an effect that is greater at higher flows. Our system has the potential for the calibration and optimization of existing commercial CTP devices.
Abstract WP57: Utility of Flat Panel CT Perfusion for Physiologic Assessment of Acute Ischemic Stroke in the Angiography Suite
Authors: Ryan Robert W , Eboli Paula , Alexander Michael J , Song Shlee S , Maya Marcel M , Moser Franklin G
Published: July 2021

Introduction
The decision to perform endovascular intervention in patients with acute ischemic stroke (AIS) may be guided by physiologic imaging such as CT perfusion (CTP) demonstrating a salvageable penumbra, but such studies can delay transfer to the angiography suite. Flat Panel Detector CT (FPD-CT) allows pre, intra and post-procedural physiologic assessment using rotational images acquired on the angiography table; however these measurements have not been correlated with conventional perfusion techniques. We began a prospective, observational comparison of standard, multi-slice CTP with FPD-CT perfusion for AIS interventions, and report our initial results.

Methods
Patients with AIS that are candidates for endovascular intervention and have standard CTP images available were enrolled in the study after obtaining informed consent and following the IRB approved protocol. FPD-CTP images were obtained with aortic contrast injection and commercially available workstation image assessment (Siemens, Erlangen, Germany) before and after intervention, and compared with standard CT perfusion and follow up images.

Results
A total of 3 cases have been enrolled. All demonstrated anatomic correlations between perfusion defects in the standard CTP and the FPD-CTP. Case example: A 58 year old man developed left sided hemiplegia and standard CTP demonstrated a right MCA defect with a small core infarction (Fig 1 A). Pre-intervention FPD-CTP showed the same defect pattern (Fig 1 B), and successful mechanical thrombectomy was performed (Fig 1 C,D). Post-intervention FPD-CT showed reversal of perfusion defect outside the core infarct (Fig 1 E). The patient had good clinical recovery and only small infarct on follow up CT (Fig 1 F).

Conclusions
Early experience with FPD-CTP imaging shows correlation with standard CTP images and reversal of perfusion defect following successful recanalization, suggesting it may be a valuable aid for decision making in AIS intervention.
Abstract WP59: IV rt-PA Treatment Response of The STROKE100 Club:
Sy
stematic
Te
chnique for
Ri
sk and
Ou
tcome Measurements Using
Key El
ements Totaling 100.
Authors: Guzik Amy K , Raman Rema , Ernstrom Karin , Meyer Dawn M , Hemmen Thomas , Pancioli Arthur , Meyer Brett C
Published: July 2021

Background:
Advanced age and high NIHSS are independent predictors of poor AIS outcome. While not excluded from IV rtPA, response is debated in these groups. Patients in the “STROKE 100 Club” (AIS with any combination of age + NIHSS ≥100) have worse outcome without increased sICH. Treatment response has not been evaluated. We evaluated 90 day outcome in the “STROKE 100 Club” with or without rt-PA.

Methods:
The UCSD SPOTRIAS prospectively collected database was analyzed for “STROKE 100 Club” patients, and all AIS patients either ≥ 80 years old or with NIHSS ≥ 20. Multivariable regression models were used with treatment group as independent variable. Models were adjusted for pre-specified covariates: pre-stroke mRS, diabetes, and atrial fibrillation.

Results:
We identified 82 STROKE 100 Club patients; 24 were untreated, 58 received IV rtPA. IV tPA treated patients were less likely to have prior history of stroke (22.8% vs 54.2%, p=0.0089). No treatment difference was seen in discharge destination, death, or poor outcome (mRS 3-6) at 90 days. In patients either ≥ 80 years old or with NIHSS ≥ 20, no difference was seen in 90 day outcomes between IV tPA and untreated patients, controlling for baseline variables. In patients ≥ 80 years old, poor outcome was associated with higher NIHSS (OR 1.16, 95% CI 1.09-1.24, p<0.0001) and mRS 3-6 (OR 5.28, 95% CI 1.64-16.96, p=0.0052). Higher NIHSS was also associated with death (OR 1.11, 95% CI 1.06-1.16, p<0.0001) and discharge to facility (OR 1.17 95% CI 1.10-1.24, p<0.0001).

Conclusions:
Prognosis remains a concern in patients with various permutations of stroke severity and advanced age. Patients ≥80 with higher NIHSS had worse outcome, confirming our prior findings in the STROKE 100 club. Interestingly, IV tPA in the STROKE 100 Club did not lead to worse outcome. IV rtPA remains a safe treatment option for patients in the STROKE 100 club. Ongoing analyses may identify subgroups at greater or lesser benefit of thrombolysis. Planned analyses include assessment in a larger NIH-SPOTRIAS cohort.
Abstract WP6: Cerebral Mechanical Thrombectomy Device Related Adverse Events: Analysis of the Manufacturer and User Facility Device Experience Database
Authors: Tekle Wondwossen G , Adil Malik M , Uluduz Derya , Rahim Basit , Awan Tauhid , Rahman Haseeb A , Hassan Ameer E , Qureshi Adnan I
Published: July 2021

Background:
There is paucity of knowledge regarding the spectrum of neurothrombectomy(NT) device-related complications.

Objective:
To report the characteristics and proportions of reported adverse-events(AE) related to NT devices used in endovascular treatment of acute ischemic stroke (AIS).

Methods:
We identified NT device-related AE reported by voluntary sources, user facility reports, and distributor and manufacturer reports to the Manufacturer and User Facility Device Experience Database(MAUDE) from the year 2004 through 2012 to identify patients. Frequency of specific reported AE and associated factors were extracted from the “event description” on the three NT devices currently in use for AIS treatment -Merci Retriever, Penumbra System, and Solitaire-FR stentriever.

Results:
A total of 706 reported NT device-related AEs were identified with a continual increase in reporting rate since 2004. Of the 706, device malfunction (kink, twist, difficult advancing, fracture, or retention) was the most common reported complication(56%), followed by hemorrhages(23%), dissection(6.8%), vasospasm(6.2%), and distal embolism(2.7%). Intra-arterial(IA) thrombolytic was used in 70%(111/159), intravenous(IV) thrombolytic in 16%, and both IA and IV in 13% of the reported cases. Middle cerebral artery(MCA) was involved in 56%(220/392), internal carotid artery(ICA) in 16 %, and both MCA and ICA in about 21% of cases where the occluded vessel was reported. Multiple devices were used in majority(71%) of reported cases(n=564). The first “pass”(recanalization-attempt) was associated with 34% of reported adverse event per-device(n= 119), 2-passes(29%), and 3-passes(28%). Recanalization was complete in 52 %(266/513) reported cases, and partial in 14%(71/513). Patients’ condition was unchanged in 63%(220/349), worsened in 29%(101/349), and improved in 8%(28/349) of reported cases. Twenty three percent(77/342) mortality was reported among those patients whose final outcome was known and reported.

Conclusions:
Reports of NT device-related AE have significantly increased over the last 8 years. Proportionally higher-rates of reported device malfunction do not necessarily represent adverse patient outcomes.
Abstract WP69: The Effect Of Time To Treatment On Outcome In Very Elderly Thrombolysed Stroke Patients
Authors: Frank Benedikt , Fulton Rachael L , Lees Kennedy R ,   on behalf of the VISTA Collaboration
Published: July 2021

Background:
Therapeutic benefit/risk from thrombolysis in acute ischaemic stroke declines sharply with delayed initiation of treatment (OTT), the window closing around 4.5hours from stroke onset. Recent overview data have indicated that risk/benefit from alteplase initiation within approximately 3 hours from stroke onset does not deteriorate with advancing age. However, some clinicians speculate that the gradient of the OTT-benefit relation may be steeper in the elderly.

Methods:
We assessed the relation between OTT and the effect of thrombolysis among 3063 registry patients with reliable surrogate information on OTT. After replicating the pooled thrombolysis-trial analysis findings among younger patients, we analysed the subgroup of patients aged >80 years. We matched non-thrombolysed patients (control; n=245) having a recorded OTT of the investigational drug to thrombolysed patients (treatment; n=352) having a recorded OTT of alteplase ≥1h and ≤3.5h, using data from neuroprotectant trials held within the Virtual International Stroke Trials Archive (VISTA).

Results:
Adjusted for baseline NIHSS and age, the OR for improved 90 day outcome with thrombolysis measured by the modified Rankin Score was 1.46 (95% CI 1.08-1.97, p=0.001). There was no significant interaction with OTT (p=0.465), but CIs were wide. The decay in benefit with increasing OTT appears little different to that established for younger patients.

Conclusion:
Evidence from multiple sources is consistent. We conclude that thrombolysis is effective and safe in very elderly stroke patients until at least 3.5h after stroke onset.
Abstract WP7: Leukoaraiosis And Outcomes After Intra-arterial Therapy In Acute Ischemic Stroke
Authors: Giurgiutiu Dan-Victor V , Yoo Albert J , Fitzpatrick Kaitlin , Chaudhry Zeshan , Schwamm Lee H , Rost Natalia S
Published: July 2021

Background:
Selecting patients most likely to benefit (MLTB) from intra-arterial therapy (IAT) is essential to assure favorable outcomes after intervention for acute ischemic stroke (AIS). Leukoaraiosis (LA) has been linked to infarct growth, risk of hemorrhage after IV rt-PA, and poor post-stroke outcomes. We investigated whether LA severity is associated with AIS outcomes after IAT.

Methods:
We analyzed consecutive AIS subjects from our institutional GWTG-Stroke database enrolled between 01/01/2007-06/30/2009, who met our pre-specified criteria for MLTB: CTA and MRI within 6 hours from last known well, NIHSS score ≥8, baseline DWI volume (DWIv) ≤ 100 cc, and proximal artery occlusion and were treated with IAT. LA volume (LAv) was assessed on FLAIR using validated, semi-automated protocols. We analyzed CTA to assess collateral grade; post-IAT angiogram for recanalization status (TICI score ≥2B); and the 24-hour CT for symptomatic ICH (sICH). Logistic regression was used to determine independent predictors of good functional outcome (mRS≤ 2) and mortality at 90 days post-stroke.

Results:
There were 48 AIS subjects in this analysis (mean age 69.2, SD±13.8; 55% male; median LAv 4cc, IQR 2.2-8.8cc; median NIHSS 15, IQR 13-19; median DWIv 15.4cc, IQR 9.2-20.3cc). Of these, 34 (72%) received IV rt-PA; 3 (6%) had sICH; 21 (44.7%) recanalized; and 23 (50%) had collateral grade ≥3. At 90 days, 15/48 (36.6%) were deceased and 15/48 had mRS≤ 2. In univariate analysis, recanalization (OR 6.2, 95%CI 1.5-25.5), NIHSS (OR 0.8 per point, 95%CI 0.64-0.95), age (OR 0.95 per yr, 95%CI 0.89-0.99) were associated with good outcome, whereas age (OR 1.1, 95%CI 1.01-1.14) and HTN (OR 5.6, 95%CI 1.04-29.8) were associated with mortality. In multivariable analysis including age, NIHSS, recanalization, collateral grade, and LAv, only recanalization independently predicted good functional outcome (OR 21.3, 95%CI 2.3-199.9) and reduced mortality (OR 0.15, 95%CI 0.02-1.12) after IAT.

Conclusions:
LA severity is not associated with poor outcome in patients selected MLTB for IAT. Among AIS patients considered likely to benefit from IAT, only recanalization independently predicted good functional outcome and decreased mortality.
Abstract WP74: Long-term Outcome Of Cognition Related To Treatment And Observation In Unruptured Intracranial Aneurysms
Authors: Holcombe Andrea , Meissner Irene , Torner Jim , Piepgras David , Huston John , Zhang Jie , Brown Robert ,   ISUIA Investigators
Published: July 2021

INTRODUCTION:
Cognitive changes can occur following procedural interventions and subarachnoid hemorrhage in unruptured intracranial aneurysms (UIA). The International Study of Unruptured Intracranial Aneurysms conducted cognitive assessment using the Mini-Mental State Exam at baseline and the Telephone Interview Cognitive Status Exam (TICS) at follow-up.

Hypothesis:
The purpose of this analysis was to compare the 1 year and 5 year outcome in the treatment cohorts (surgery and endovascular) with those of the untreated subgroup.

Methods:
Patients were subdivided into the initial treatment and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort and 2388 in the treated cohort. The cohorts were followed annually with measures of neurological status, Rankin Scale and cognition (TICS). Outcomes were determined prospectively. Comparison of outcomes was done using continuous data and by categories. Covariate adjustment was done using general linear models. Stratified analysis was done by Rankin Score at the time of follow-up.

Results:
The mean TICS score at 1 year in the cohort was 33.4 with a median of 34 (maximum is 40). In the treated patients the mean was 33.5 and in the untreated patients it was 33.3 (P=0.644). However, Rankin Score at 1 year was significant with a higher percentage of 3-5 scores in the treated group (P=0.003) Categorical analysis of the TICS Score when stratified by Rankin Score at 1 year showed small but significant differences, P=0.03 for Rankin 0-2, and P=0.07 for Rankin 3-5. However after adjustment for baseline variables treatment TICS Score was no longer significant.. The 5 year results showed that the untreated patients did worse than the treated group in TICS. However after adjustment no differences were apparent.

Conclusions:
Cognitive changes associated with treatment may be minor source of disability post-treatment compared to observation and patient outcomes may be worse in the observation group over time. Differences in outcome also were better explained through the Rankin Score at follow-up than by cognitive deficits.
Abstract WP79: Choice Of Treatment And Effect On Hemorrhage Rates Of Unruptured Intracranial Aneurysms
Authors: Torner James , Zhang Jie , Piepgras David , Huston John , Meissner Irene , Brown Robert ,   ISUIA Investigators
Published: July 2021

INTRODUCTION:
The decision regarding whether to perform an interventional procedure as a strategy to prevent hemorrhage of an unruptured intracranial aneurysm (UIA) requires careful consideration of procedural risk and the UIA natural history. No randomized trial data are available. The International Study of Unruptured Intracranial Aneurysms (ISUIA) included a prospective cohort, examining hemorrhage risk and treatment risk.

Hypothesis:
The purpose of this analysis was to compare the factors related to treatment selection and determination of the number of hemorrhages prevented.

Methods:
Patients were allocated into the initial treatment and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort, 471 were in the endovascular cohort and 1917 patients were in the surgical cohort. The cohorts were followed for a median follow-up of 9.2 years. Outcomes were determined prospectively and with central review. The data were grouped together and analyzed to determine treatment decisions. A Cox proportional hazards model predicting hemorrhage developed in the observation cohort and was applied to the surgery and endovascular cohorts across the follow-up period.

Results:
Significant baseline variable differences between treated and observed patients were aneurysm size, symptoms, age, prior SAH group, geographical region, treatment percentage, aneurysm daughter sacs or multiple lobes, and history of hypertension, smoking and myocardial infarction. Aneurysm site and family history were not significant. Site, size, and aspirin use were significant predictors of hemorrhage.

Long-term the predicted hemorrhage rates were 6.7% at 5 years and 8.0% at 10 years in the surgery group and 8.1% and 9.6% for the endovascular group, respectively. For comparison the rates in the observed cohort were 4.1% and 4.8%, respectively.

Conclusions:
Decisions for treatment are influenced by patient characteristics such as age and medical history, aneurysm characteristics such as size and morphology and center and regional practices. Patients in the treated cohorts were at moderately increased risk for hemorrhage compared to those in the observed cohort.
Abstract WP82: Effect Of Ultra-early Endovascular Intracranial Aneurysm Treatment On Rebleeding And Outcomes In Patients With Subarachnoid Hemorrhage
Authors: Tariq Nauman , Sit Nathan , Adil Malik M , Rizvi Ashter , Gilani Waqas I , Qureshi Adnan I
Published: July 2021

Background:
The American Heart Association (AHA) recommends early aneurysm treatment without specifying any specific time intervals in patients with subarachnoid hemorrhage [SAH] [Bederson JB, et al.Stroke. 2009;40:994-1025].The AHA further requires documentation of proportion of SAH patients treated within 36 hours after admission as a Quality of Care metrics in Comprehensive Stroke Centers. [Leifer D, et al. Stroke. 2011; 42: 849-877]However, the definition of early treatment remains controversial.

Objective:
To determine the rates of outcomes associated with ultra-early (<12 hours) and delayed (≥12 hours) intracranial aneurysm treatment after admission in patients with SAH.

Methods:
We analyzed the data from 144 consecutive SAH patients from two academic centers who underwent endovascular treatment of ruptured intracranial aneurysms over a period of 4 years. Pre procedure rebleeding was defined by an acute neurological deterioration associated with new hemorrhage apparent on a computed tomographic (CT) scan or an increase in hemorrhage burden on a repeat CT scan. Favorable outcome was defined as modified Rankin score of ≤2 at discharge. Baseline characteristics and outcomes were compared between ultra-early (<12 hours) and delayed (≥12 hours) treatment using univariate analysis and by multivariate analysis after adjustment for confounders.

Results:
Of the 144 SAH patients (mean age 54±SD: 13). Ninety nine ( 68% ) were women who underwent endovascular intracranial aneurysm treatment, (58%) underwent ultra-early aneurysm treatment. After adjusting for age, Hunt and Hess and Fisher grades, there was no significant difference in rates of favorable outcomes (odd ratio [OR] 0.6, 95% confidence interval [CI](0.2-1.3) or in-hospital mortality (OR 0.8, 95% CI (0.3-2.3) between the two groups. Pre procedure rebleeding was less likely to occur in the ultra-early treatment group (OR 0.1; 95% CI 0.02-0.4, p<0.002).

Conclusions:
Ultra-early aneurysm treatment is possible due to the availability of endovascular treatment and appears to significantly reduce the pre-procedural rebleeding rates in patients with SAH.
Abstract WP87: Endovascular Treatment of Very Small Ruptured Intracranial Aneurysms: Complications, Occlusion Rates and Prediction of Outcome
Authors: Starke Robert M , Chalouhi Nohra , Ali Muhammad S , Penn David L , Tjoumakaris Stavropoula I , Jabbour Pascal M , Gonzalez L. Fernando , Rosenwasser Robert H , Dumont Aaron S
Published: July 2021

Purpose:
In this study we assess predictors of outcome following endovascular treatment of small ruptured intracranial aneurysms (SRA).

Methods:
Between 2004 and 2011, 91 patients with SRA (≤ 3 mm) were treated at our institution. Multivariate analysis was carried out to assess predictors of endovascular related complications, aneurysm obliteration (>95%), recanalization, and favorable outcome (Glasgow Outcome Scale 3-5).

Results:
Endovascular treatment was aborted in 9 of 91 patients (9.9%). Procedure-related complications occurred in 8 of 82 patients (9.8%) of which 5 were transient and 3 were permanent. Three patients (3.7%) undergoing endovascular therapy experienced an intra-procedural aneurysm rupture. Three of 9 patients (33.3%) treated with stent or balloon assisted coiling experienced peri-procedural complications compared to 5 of 73 patients (6.8%) receiving only coils or Onyx (p=0.039). There were no procedural deaths or rehemorrhages. Rates of recanalization and retreatment were 18.2% and 12.7%, respectively. No factors predicted initial occlusion or recanalization. In multivariate analysis pre-treatment factors predictive of favorable outcome included younger age (OR=0.94; 95% CI 0.91-0.99, p=0.017), larger aneurysm size (OR=3.4; 95% CI 1.02-11.11, p=0.045), Hunt and Hess grade (OR=0.38; 95% CI 0.19-0.75, p=0.005), and location (OR=5.12; 95% CI 1.29-20.25, p=0.02). When assessing treatment and post-treatment variables, vasospasm was the only additional covariate predictive of poor outcome (OR=5.90; 95% CI 1.34=25.93, p=0.019).

Conclusions:
The majority of SRA can be treated with endovascular therapy and limited complications. Overall predictors of outcome for patients undergoing endovascular treatment of SRA include age, aneurysm size, Hunt and Hess grade, location, and post-treatment vasospasm.
Abstract 109: Manipulative Dexterity is Associated with Occult White Matter Ischemic Lesions in Healthy Asymptomatic Persons at Increased Risk for Cardiovascular Disease
Authors: Nyquist Paul A , Yanek Lisa R , Bilgel Murat , Cuzzocreo Jennifer L , Becker Lewis C , Chevalier Karinne , Woessner Terry , Prince Jerry , Becker Diane M
Published: July 2021

Introduction:
Persons with a family history of early-onset coronary artery disease (CAD) have an excess risk of stroke and CAD. White matter lesions (WML) on MRI represent small vessel ischemic cerebrovascular disease and are associated with incident stroke and neurocognitive decline with age. We hypothesized manipulative manual dexterity, an integration of fine motor, visual spatial, and cognition function, may be affected by increased WML burden in task-relevant brain regions across age ranges in persons at risk for pre-clinical occult vascular disease. We tested this in a large population with a family history of early CAD.

Methods:
Healthy 29-74 year old subjects (N=714; mean age 51± 11 years; mean education 14 ± 3 years; 42% male, 38% Black) were identified from probands with CAD <60 years. WML location and volumes were measured on 3T FLAIR MRI. Manipulative manual dexterity was measured with standardized timed grooved pegboard test. Left and right pegboard scores were averaged.

Results:
WML were observed in all age groups; mean overall pegboard scores were 108±18, and were within reference norms. In unadjusted analysis, pegboard scores were highly correlated in the expected direction with total WML volumes, r=0.34, p=<.0001; subcortical volumes r=0.30, <.0001 periventricular volumes r=0.31, <.0001; and with most regional WML volumes; frontal 0.34, <.0001; insula r=0.31, p<.0001, parietal r=0.31, p<.0001, and temporal volumes r=0.17, p <.0001. In separate multivariate regression analyses predicting (log) pegboard score adjusted for age, sex, race, education and nonindependence of families (GEE), total WML volume became more statistically significant ( p=5.79E-05) while other regions retained statistical significance, p< 0.01.

Conclusions:
Our findings in a large population-based sample with a family history of early CAD confirm that greater WML volumes in multiple brain locations are associated with higher pegboard scores (worse performance) independent of age, sex, race, and education. This suggests that small vessel cerebrovascular disease is present in an early preclinical state and that WML volumes impact manipulative manual dexterity in healthy middle-aged and younger individuals with excess risk for clinical vascular disease.
Abstract 117: A Six Minute MRI Protocol for Evaluation of Acute Ischemic Stroke: Pushing the Boundaries
Authors: Nael Kambiz , Khan Rihan , Choudhary Gagandeep , Meshksar Arash , Dumont Travis , Tay Jennifer , Drake Kendra , Coull Bruce
Published: July 2021

Purpose:
Multimodal cerebrovascular CT and MR can now provide information about tissue viability, site of occlusion, and collateral status in patients with acute ischemic stroke (AIS). If MRI is to compete with CT for evaluation of AIS, there is need for further improvements in acquisition speed. The purpose of this study was to establish the feasibility of a fast MR protocol with a 6 minute acquisition time for evaluation of AIS.

Methods:
Patients with suspicion of AIS and absence of MRI contraindications were prospectively enrolled. A combination of echo-planar imaging (EPI) and parallel acquisition technique were used on a 3T MR scanner to accelerate the acquisition time. The imaging protocol included: DWI (1 min), EPI-FLAIR (52 sec), EPI-GRE (50 sec), contrast-enhanced MR angiography (CE-MRA) of the entire supra-aortic arteries (20 sec), and DSC perfusion (2 min). Using a modified 2-phase contrast injection scheme, high spatial resolution CE-MRA of the supra-aortic arteries was performed just before DSC perfusion without the need for additional contrast. Image analysis was performed independently by two neuroradiologists and interobserver agreement was calculated using Kappa test.

Results:
A total of 50 patients were included. Diagnostic image quality was achieved in 100% of DWI, 96% EPI-FLAIR, 98% EPI-GRE, 90% neck MRA, 96% of brain MRA, and 94% of DSC perfusion scans. Thirty eight patients (76%) had acute infarction. Using Tmax perfusion maps and applying DEFUSE criteria, 42% of patients had perfusion-diffusion mismatch with interobserver agreement of k=0.90. The mean of the signal-intensity-ratio values of the infarction on EPI-FLAIR was 1.08 for patients presenting < 4.5 hours (n=16) and 1.35 for patients presenting > 4.5 hours (n=22) from the time of imaging. Three patients had evidence of intracranial hemorrhage detected on EPI-GRE and confirmed by non-contrast CT. CE-MRA showed 27 segmental stenoses of the extra-cranial arteries and 24 segmental stenoses of the intracranial arteries with interobserver agreement of k= 0.82 and 0.74 respectively.

Conclusion:
Described multimodal MR protocol is feasible for evaluation of patients with AIS and can result in significant reduction in scan time rivaling that of the multimodal CT protocol.
Abstract 118: Diffusion Lesion Volume Reduction after Recanalization Therapy for Anterior Circulation Stroke with Major Vessel Occlusion: Analysis from the RESCUE-Japan Registry Study
Authors: Hayakawa Mikito , Yamagami Hiroshi , Toyoda Kazunori , Matsumaru Yuji , Enomoto Yukiko , Egashira Yusuke , Okada Yasushi , Kitagawa Kazuo , Kimura Kazumi , Tanahashi Norio , Hyogo Toshio , Sakai Nobuyuki , Yoshimura Shinichi ,   The Recovery by Endovascular Salvage for CerebralUltra-acute Embolism (RESCUE)-Japan Study Group
Published: July 2021

Objective:
Although Diffusion-weighted imaging (DWI) lesions are commonly irreversible, DWI lesion volume reduction (DVR) is occasionally observed. We investigated clinical significance and predictors of DVR in acute stroke patients with major vessel occlusion receiving recanalization therapy (RT).

Methods:
The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism (RESCUE)-Japan registry prospectively registered 1,442 stroke patients with major vessel occlusion who were admitted to 84 Japanese stroke centers within 24 hours after onset from July 2010 to June 2011. We retrospectively analyzed all patients with the internal carotid artery or middle cerebral artery (M1 or M2 segments occlusions receiving RT and undergoing MRI both on admission and at 24 hours after onset from the registry. We defined DVR as a 1 or more-point reduction of the DWI-Alberta Stroke Program Early CT Score (ASPECTS), and CT-DWI mismatch (CTDM) as a 2 or more-point lower DWI-ASPECTS than CT-ASPECTS on admission. Reperfusion was defined as TICI grade 2b-3 on catheter angiography or modified Mori grade 3 on MRA immediately after RT. Dramatic recovery (DR) was defined as a 10 or more-point reduction or a total NIHSS score of 0-1 at 24 hours, and favorable outcome (FO) defined as a mRS score 0-2 at 3 months.

Results:
A total of 390 patients (215 men, 72 years old,) was included. Median baseline NIHSS score was 16 (IQR 10-19) and median baseline DWI-ASPECTS was 8 (6-9). CTDM was seen in 92 patients (28%) on admission. Intravenous thrombolysis and endovascular therapy were performed in 246 patients (63%) and 223 patients (57%), respectively. Reperfusion was obtained in 170 patients (51%). DVR was seen in 51 patients (13%). Eighty-eight patients (23%) obtained DR and 158 patients (41%) achieved FO. On multivariate analyses, DVR was significantly related to DR (OR 3.8, 95%CI 1.5-10) and FO (4.6, 1.8-12). CTDM was an independent predictor of DVR (OR 2.5, 95% CI 1.1-5.8).

Conclusions:
DVR was significantly related to DR and FO. CTDM is a rough predictor of DVR of which area is considered as a “DWI-bright” ischemic penumbra, and might be a useful marker to identify the adequate candidates for RT in spite of relatively large DWI lesions.