bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract T P40: Pre-Treatment Hyperdense Middle Cerebral Artery Sign Predicts the Outcome of Intra-Arterial Thrombectomy for Acute Stroke
Authors: Man Shumei , Hussain M. Shazam , Wisco Dolora , Cheng-ching Esteban , Uchino Ken
Published: March 2022

Background:
Intra-arterial (IA) mechanical thrombectomy has an excellent recanalization rate but does not always correlate with good clinical outcomes. We aimed to investigate whether the location and length of hyperdense middle cerebral artery sign (HMCAS) on pre-intervention Non-Enhanced CT (NECT) can predict IA therapy outcome for acute stroke.

Methods:
Data were abstracted from our Hyperacute Ischemic Stroke database. Patients with occlusion in ICA, MCA or MCA M2 branches who underwent IA therapy were included. HMCAS was retrospectively analyzed. The length and location of HMCAS on NECT was retrospectively analyzed. Based on the location, HMCAS was categorized into four groups: Proximal HMCAS: hyperdensity within the proximal half of M1 MCA; Distal HMCAS: hyperdensity at the distal half of M1; Full length HMCAS; and Hyperdense M2. The first three groups were referred as M1 HMCAS.

Results:
Among 126 patients who underwent IA treatment, 64 (51%) had M1 HMCAS, 11 (9%) had hyperdense M2, and 51 (40%) had no HMCAS (No HMCAS group). There was no difference between these two groups in pre-treatment stroke severity, infarct volume, and recanalization rate defined on post intervention cerebral angiogram (p>0.05). There were no differences between M1 HMCAS and No HMCAS groups in favorable outcome defined as modified Rankin scale score 0-2 at 30 days (21% versus 30%, p=0.29, see figure). For those with HMCAS, functional outcome was associated with the location of HMCAS. Favorable 30 day outcome was most frequent in Distal HMCAS (39%), followed by hyperdense M2 (27%), HMCAS proximal (11%), and HMCAS full length (0%, p=0.0053).

Conclusion:
For acute ischemic stroke due to large vessel occlusion, the lack of HMCAS on NECT does not predict favorable outcome after IA therapy. Among those with hyperdense vessel sign, proximal and longer HMCAS predicts unfavorable outcome.

1
Abstract T P43: Detection of Advanced Leukoaraiosis Does Not Augment Imaging-Enhanced Prediction of Early Stroke Risk in Transient Ischemic Attack
Authors: Siket Matthew S , Baird Janette , Ay Hakan
Published: March 2022

Background:
The risk of stroke following transient ischemic attack (TIA) is high in patients with evidence of transient symptoms with infarction (TSI) on CT or diffusion-weighted imaging (DWI). The extent to which leukoaraiosis augments imaging-based risk prediction is unresolved. We sought to determine whether the presence of advanced leukoaraiosis improves the predictive performance of early CT and MR-based neuroimaging modalities in patients diagnosed with clinical TIA.

Methods:
We retrospectively identified 37 cases of 30-day recurrent stroke that had MRI performed within 1 day of presentation, and compared to 43 patients without recurrence from a larger cohort of 1250 patients admitted to the hospital from a single emergency department with suspected TIA between 1/1/2000 and 7/16/2011. In all subjects (n=80), CT and MR (DWI and T2Flair)images were reviewed by a physician reader blinded to outcome and graded for the presence of abnormalities such as acute infarction, prior infarction, and advanced leukoaraiosis as defined by a Van Sweiten scale of 2 in either the anterior or posterior regions. We assessed the predictive performance of DWI alone, CT for infarction, CT for any abnormality and MRI for any abnormality by computing the area under the receiver-operating characteristics curve.

Results:
The sensitivity of CT increased from 14% to 71% and MR from 68% to 93% in predicting 30-day stroke recurrence upon inclusion of acute or old infarction or advanced leukoaraiosis. Specificity decreased from 100% to 44% and 67% to 30% respectively. The area under the receiver-operating characteristic curve was 0.57 for CT for infarction alone and 0.58 for CT including leukoaraiosis; 0.68 for DWI alone and 0.61 for DWI or T2Flair evidence of old infarction or advanced leukoaraiosis.

Conclusions:
The addition of advanced leukoaraiosis does not appear to add to the predictive ability of CT or MRI-based neuroimaging in the early risk stratification of patients with TIA.
Abstract T P45: Task Fmri Based Functional Connectivity in Acute Stroke Patients With and Without Motor Impairments
Authors: Nair Veena A , La Christian , Young Brittany M , Andreoli Mathew , Reiter Peter , Jensen Matthew B , Chacon Marcus , Sattin Justin , Prabhakaran Vivek
Published: March 2022

Introduction:
Several studies employing functional/effective connectivity methods have reported performance-related changes in the motor network after stroke. We investigated changes in the motor network in a group of acute stroke patients (less than 7 days from stroke onset) with and without motor impairments compared to age-matched healthy controls.

Methods:
Seed regions for task-based functional connectivity were based on peak coordinates of significant clusters of activation associated with right-hand finger tapping task in the scanner, derived from 13 left hemisphere stroke patients (mean age 63 yrs, 11 right handed) and 13 age-matched healthy controls. These regions were then used to examine seed-based functional connectivity in 23 patients (12 with motor impairment [7 LH strokes, avg. age of 59, 10 rt handed], and 11 without [7 LH strokes, avg. age of 63, 9 rt handed]. Motor impairment was based on self-reported scores on the hand strength and hand function domain of the Stroke Impact Scale(Duncan et al., 2003). The Network Based Statistics Toolbox (Zalesky, Fornito, & Bullmore, 2010), which uses a non-parametric approach based on permutation tests, was used to test differences in functional connectivity.

Results:
Compared to patients without motor impairments, patients with impairments showed reduced connectivity (p < .05, corrected) in a network comprising of connections between the right inferior parietal and right cerebellum, right precentral central (PCG) and left thalamus, left post central gyrus and right cerebellum, left SMA and right cerebellum. Compared to controls, patients with impairments showed reduced connectivity (p < .05, corr) in a network comprising of connections between the right PCG and left thalamus, right PCG and bilateral cerebellum. There were no differences in functional connectivity patterns in stroke patients without motor impairments compared to healthy controls.

Conclusions:
Compared to patients without motor impairments, patients with motor impairments showed reduced intra- and inter-hemispheric functional connectivity. When compared to healthy controls, patients with motor impairments showed reduced intra-hemispheric connectivity in the ipsilateral hemisphere.
Abstract T P49: Improving Outcome of Placebo- but not Albumin-Treated Subjects Over the Course of the ALIAS Part 2 Multicenter Trial: Differential Influence of Thrombolytic Therapy
Authors: Ginsberg Myron D , Hill Michael D , Moy Claudia S , Barsan William G , Tamariz Diego , Ryckborst Karla J
Published: March 2022

In the ALIAS2 Trial, 841 subjects were randomized 1:1 to treatment with either 25% albumin (ALB, 2 g/kg) or normal saline within 5 hours of stroke onset, and the primary outcome (NIHSS 0-1 and/or modified Rankin scale 0-1) was assessed at 90 days. While overall outcomes did not differ by treatment (44% for both groups), we observed a steadily improving favorable rate in the saline-placebo arm but not in the ALB arm over the trial’s 3.5 year course. This was further analyzed here.

Methods and Findings:
Logistic regression confirmed a significant randomization-order x treatment interaction (p<0.001). Thus, at the first pre-specified interim analysis of N=275 subjects, favorable outcome was seen in 44.8% with ALB but only 30.3% with saline (relative benefit 1.48, p=0.0028), while at the second interim analysis of N=550 subjects, the saline rate had risen to 37.5% while the ALB rate remained steady at 44.6% (relative benefit 1.21, p=0.0176). This trend-over-time in saline subjects was highly significant (Jonckheere-Terpstra (J-T) test, p=0.001; Pearson coefficient r=0.792), but there was no such trend in ALB subjects (J-T p=1.000). Simulation analysis confirmed that the saline trend could not have arisen by chance (p=0.0007). Importantly, intravenous tPA use also increased significantly during the trial in both ALB and saline subjects (initial rate 74%, final rate 95%, p<0.0001). Separate logistic regression analyses revealed a highly significant effect of IV tPA use on outcome in saline subjects (odds ratio 2.8, 95% CI 1.5-5.3, p=0.001) but only a marginal effect in ALB subjects (odds ratio 1.7, p=0.06).

Conclusion:
ALB treatment appears to have conferred a stable (and desirable) therapeutic “ceiling effect” throughout the trial (in the absence of significant toxicity), while saline subjects (who were unable to benefit from ALB) were susceptible to improved outcome from increasing tPA use as the trial progressed.
Abstract T P55: The Safety and Efficacy of Alteplase for Acute Ischaemic Stroke in Chinese Patients
Authors: Chao A-Ching , Hu Han-Hwa
Published: March 2022

Background:
The relationship between the dose of alteplase and its safety/efficacy for ischaemic stroke has not been well evaluated in the Asian population. In the present study, we assessed the safety/efficacy of different doses of alteplase for acute ischaemic stroke in Taiwan.

Methods:
A prospective observational study was conducted in Taiwan. Eligible patients (1,004) were classified according to the dose of alteplase (or rt-PA) received for managing acute ischaemic stroke: 0.90± 0.5 mg/kg (422 patients, mean 0.91 ± 0.05 mg/kg, median 0.9 mg/kg, range 0.86-1.26mg/kg) as the standard dose group and < 0.85 mg/kg as the lower dose group, which was further divided into three subgroups: 0.80 ± 0.5 mg/kg (202 patients, mean 0.81 ± 0.03 mg/kg, median 0.81 mg/kg, range 0.76-0.85 mg/kg), 0.70 ± 0.5 mg/kg (199 patients, mean 0.71 ± 0.02 mg/kg, median 0.71 mg/kg, range 0.68-0.75 mg/kg) and 0.60 ± 0.5 mg/kg (181 patients, mean 0.62 ± 0.04 mg/kg, median 0.61 mg/kg, range 0.55-0.65 mg/kg). The primary outcome was: symptomatic intracerebral haemorrhage (SICH) and death within three months. The secondary outcome was good clinical outcome (modified Rankin scale (mRS) ≤ 1) at three months after thrombolytic therapy.

Results:
The overall SICH rates per the NINDS (6.8%) were comparable with the results of other observational studies, and the good functional outcomes (32.4%) were also similar after excluding patients aged ≥ 80 years and those with mRS score ≥ 2 before the index stroke. There was a significant trend for SICH with age (
P
= 0.0025). From the lowest to the highest dose of alteplase in patients aged 71-80 years, we observed a significant trend of increasing SICH (
p
=0.0130) and poorer functional outcome (P=0.0179). However, these trends did not exist in younger stroke patients.

Conclusions:
Consistent with our previous study, the standard dose of alteplase, 0.9 mg/kg, is not optimal for all acute ischaemic patients in an Asian population. In elderly patients (71-80 years), a lower dose of alteplase, 0.6 mg/kg, is associated with better safety/efficacy of thrombolytic therapy for ischaemic stroke in Chinese. However, randomized trials of lower versus higher dose are still needed.
Abstract T P60: Anticoagulation for Patients With Isolated Occlusion of the Internal Carotid Artery Presenting With Stroke
Authors: Damania Dushyant , Kung Nancy T , Jain Minal , Jain Anunaya , Koch George E , Jahromi Babak S
Published: March 2022

Introduction/Background:
Current guidelines do not recommend acute anticoagulation in treatment of Acute Ischemic Stroke (AIS) patients, based upon concern for hemorrhagic transformation (HT) and lack of evidence for efficacy in acute stroke. However, anticoagulation may be reasonable in patients with carotid dissection/occlusion and/or intraluminal/intracardiac thrombus. In particular, patients with isolated acute carotid occlusion (not reaching the ICA terminus, with patent Circle of Willis) may benefit from anticoagulation to prevent worsening ischemia from further involvement at the level of the circle of Willis.

Methods:
We retrospectively analyzed 128 consecutive patients presenting with AIS and ICA occlusion from 07/2008 to 05/2013. Patients with newly (<7 days) diagnosed ICA occlusion (without involvement of the Circle of Willis) were divided into two groups based on the initial treatment within 24 hours of presentation: therapeutic anticoagulation (n=12), and medical management (n=19). Patients receiving iv-tPA or endovascular intervention were excluded. Recurrent stroke or death within 7 days and 3 months were recorded.

Results:
At three months, of the 12 patients who were anti-coagulated, 1 experienced a recurrent stroke (6
th
day) and 1 died. Of the 19 patients who were not anti-coagulated 6 developed recurrent strokes (median 3 days after initial stroke) and 2 died. Hemorrhagic transformation was not seen in either group. In the anticoagulation group, there was a trend towards decreased incidence of early stroke recurrence (< 7 days; 8.3% versus 31.6%, p=0.20), and fewer strokes or deaths within three months (16.7% vs. 42.1%, p=0.24). ICA recanalization was seen in 5 (41.7%) patients who were anticoagulated and 2 (10.5%) patients who were not anti-coagulated (p = 0.07).

Conclusion:
In a selected population of AIS patients presenting with isolated carotid occlusion (not reaching the ICA terminus and Circle of Willis), anticoagulation appears safe, and may be correlated with fewer early recurrent strokes and increased carotid recanalization on follow up. Larger scale prospective studies for this specific patient population may be justified.
Abstract T P61: Patients With Acute Stroke Involving More Than One-Third Middle Cerebral Artery Territory Should Not be Excluded From Intravenous Thrombolysis
Authors: yeo leonard , Paliwal Prakash , Chan Bernard P , Teoh Hock Luen , Ong Venetit H , Sharma Vijay
Published: March 2022

Background and aim:
Involvement of more than one-third of middle cerebral artery (MCA) territory on initial brain CT is a relative contraindication for IV-tPA and often associated with increased bleeding risk. Involvement of more than 1/3 MCA territory on initial CT is associated with poor functional outcome at 3 months. We present the results of IV-thrombolysis among these patients at our tertiary care centre.

Methods:
Data from consecutive acute ischemic stroke (AIS) patients treated with IV-tPA within 4.5 hours between January 2009 to August 2012 were included. The collected data included demographic characteristics, vascular risk factors, National Institute of Health Stroke Scale (NIHSS) scores, and blood pressure levels before IV-tPA bolus. The presence of early stroke signs involving more than 1/3 of the MCA on the initial CT scan was measured by Alberta Stroke Program Early CT score (ASPECTS ≤7). Outcomes were assessed by modified Rankin Scale (mRS) score at 3 months.

Results:
A total of 97 AIS patients with more than one-third MCA involvement received IV-tPA during the study period. Median age was 70 yrs (range 38-89), 55% male, median NIHSS score 20 points (range 3-33) and median onset-to-treatment time 152 minutes (range 55-274). Forty-two (44%) patients achieved good functional outcomes at 3 months (mRS score 0-1). Factors associated with good outcome at 3 months on univariate analysis were younger age, hypertension, non-cardioembolic etiology and lower NIHSS score at presentation. After multivariate analysis, lower age (OR 0.965; 95%CI 0.941-0.989, p=0.005) and lower NIHSS scores at presentation were noted as independent predictor of good outcome at 3 months (OR 0.990; 95%CI 0.869-0,950 p= <0.001 ). The presence of more than1/3 MCA involvement on the ore-thrombolysis CT scan (ASPECTS <8) was not associated with a poor functional outcome at 3 months (OR 1.495 95% CI 0.881-2.540; p=0.136).

Conclusions:
Patients with acute stroke involving more than one-third of the MCA on initial brain CT scan, especially if associated with lower NIHSS score, should not be excluded from systemic thrombolysis.
Abstract T P62: The Presence of Cerebral Microhemorrhage is Not Associated With Hemorrhagic Conversion Following Post Thrombolysis for Acute Ischemic Stroke
Authors: Iwuchukwu Ifeanyi , Chan Tommy , Afshinnik Arash , Mcgrade Harold , Sabharwal Vivek
Published: March 2022

Introduction:
Hemorrhagic conversion remains an unpredictable complication of thrombolysis for acute ischemic stroke. Cerebral microhemorrhages (CMH) have been associated with intracerebral hemorrhage (ICH) and may serve as a biomarker for hemorrhagic conversion of acute ischemic stroke treated with tissue plasminogen activator. We sort to determine the relationship of the presence of CMH and hemorrhagic conversion of acute ischemic stroke treated with intravenous thrombolysis.

Method:
Using our institutional stroke registry, we identified patients with acute ischemic stroke treated with intravenous tissue plasminogen activator between the period January 1, 2012 and December 31, 2012; whose workup included an MRI with gradient recovery echo (GRE) sequence performed within 12-24 hours of receiving thrombolysis. The presence and location of CMH were recorded and compared with the presence of post thrombolytic (ICH). Variables on patient demographics, clinical history (hypertension, diabetes mellitus, hyperlipidemia, atrial fibrillation, coronary artery disease, congestive heart failure, chronic renal insufficiency), NIHSS, LDL, HDL, HbA1c, total cholesterol and ejection fraction on transthoracic echocardiogram were collected and analyzed. Statistical analysis was done using fisher exact test for categorical variables and t-test for continuous variables.

Result:
68 patients were identified and studied. Fifteen patients (23.5%) demonstrated CMH, while a total number of 45 CMH (37 lobar and 8 Non-lobar) was observed. Hemorrhagic conversion was more frequent in patients with CMH compared to patients without CMH; however, it was not statistically significant (26.7 % vs 9.4% p=0.0999). In addition, there was no difference in the frequency of parenchymal hematoma between the groups (20% vs 5.7% p=0.116). Of the clinical and laboratory variables recorded, only a history of atrial fibrillation was significantly different between the patients with and without CMH (0 vs 26.4% p=0.0289).

Conclusion:
The presence of CMH on GRE is not associated with an increased frequency of hemorrhagic conversion or presence of parenchymal hematoma following thrombolysis for acute ischemic stroke.
Abstract T P63: Stroke Averted by Tissue Plasminogen Activator Can be Predicted by Baseline Factors but is Associated With Undetermined Etiology
Authors: Monlezun Dominique J , George Alexander J , Schwickrath Melissa , El Khoury Ramy , Martin Schild Sheryl
Published: March 2022

Background:
Limited investigation of the distinction between averted and completed stroke has been performed. We sought to determine baseline characteristics predictive of averted stroke and compare the evaluation and TOAST classification in patients with averted strokes to those of patients with completed stroke.

Methods:
Patients admitted to our stroke center (07/08-06/13) and treated with IV tPA were retrospectively assessed. Patients were excluded if they were transferred from an outside hospital or if an MRI was not completed. Averted stroke was defined as complete reversal of neurological deficits within 24hrs of onset and DWI-negative MRI. Patients with DWI-negative MRI and persistent deficits or alternate identified etiology were not given a stroke diagnosis. Completed stroke was defined as DWI positive MRI. Univariate and multivariate analyses were performed for averted versus completed stroke based on baseline characteristics, work-up, and TOAST classification.

Results:
Of the 325 patients who met inclusion criteria, 106 (32.6%) experienced an averted stroke. Compared to patients with completed stroke, averted stroke patients were younger (median 61 vs 66, p<0.0001), were more likely to have prior history of stroke (35% vs 26%, p=0.0496), had lower median presenting systolic blood pressure (150 vs 157, p=0.0050), and lower median baseline NIHSS scores (6 vs 11, p<0.001) (Table). Averted stroke patients were less likely to have TEE performed (23% vs 32%, p=0.0235) even after adjustment for age, race, gender, and baseline NIHSS score (OR 0.49, CI 0.29-0.85, p=0.011). By TOAST classification, patients with averted strokes were more likely to have cryptogenic strokes (58% vs 22%, p<0.0001; adjusted OR 5.09, CI 2.98-8.70, p<0.001).

Conclusion:
Averted stroke patients were more likely to be younger, have milder strokes and have cryptogenic etiology with less extensive work-ups. Further studies are warranted to explain these baseline differences.
Abstract T P7: Endovascular Therapy with Solitaire Flow Restoration Device after Intravenous t-PA versus t-PA Alone for Stroke
Authors: Nguyen Thang H , Pham Binh N , Anh Truong L , Minh Ngo B , Vu Tran T , Nguyen Khang D
Published: March 2022

Background:
Solitaire flow restoration device have showed advantages in comparison with Merci device that is most used in endovascular therapy trials. We compared the effectiveness and safety of the additional Solitaire treatment and intravenous t-PA alone for stroke patients.

Subjects and Methods:
Consecutive patients with proximal intracranial occlusion who received intra-arterial reperfusion procedures by mechanical recanalization retrievable self-expanding stent (Solitaire group) after IV t-PA were studied. They were compared with patients from our prospective IV t-PA database with middle cerebral artery or basilar artery occlusion (IV group). Arterial occlusions were assessed with computed tomography angiography before IV t-PA treatment. Patients in Solitaire group underwent angiography as soon as possible after IV t-PA, and those with a vascular occlusion received endovascular intervention with Solitaire FR revascularization device. Clinical evaluation was assessed by National Institutes of Health Stroke Scale at baseline, 24 hours, and at discharge. Symptomatic intracranial hemorrhage was defined according to the National Institute of Neurological Disorders and Stroke trial. Functional evaluation was determined by modified Rankin Scale, with functional independence defined by modified Rankin Scale score of 2 at 3 months.

Results:
Thirty patients in the Solitaire group were compared with 74 patients in the IV group. The mean age was 59.7±12.5 years. 46 patients (44.2%) were women, and baseline median National Institutes of Health Stroke Scale score was 17 (interquartile range, 6). Mean time from symptoms to IV tPA was 151.4±47.9 minutes. More patients had good 3-month neurological outcome with Solitaire than with IV alone (56.7% vs 35.1%, p=0.04). Symptomatic intracranial hemorrhage was similar (Solitaire 6.7% versus IV 5.4%,
P
=1). Mortality at 3 months was 13.3% in the Solitaire group and 20.3% in the IV group (p=0.57).

Conclusions:
In this non-randomized study, compared with intravenous t-PA alone, additional Solitaire treatment was associated with better clinical outcome in in stroke patients with proximal intracranial occlusion.
Abstract T P70: Resolving the Relative Contribution of Resident Microglia versus Infiltrating Macrophages in the Ischemic Brain After Stroke
Authors: Ritzel Rodney , Patel Anita , McCullough Louise
Published: March 2022

Introduction:
Early after stroke local inflammatory changes are primarily mediated by microglia, the resident macrophages of the brain. As injury evolves and the vascular integrity becomes compromised, there is a robust infiltration of peripheral myeloid cells into the ischemic area. Given the common lineage ancestry and morphological similarity between bone marrow-derived (BM) macrophages and resident microglia, the two cell types become nearly indistinguishable from each other using standard immunohistological methods. To date, the most sensitive means of discerning between microglia and BM macrophages relies on the relative level of CD45 expression. In this study, ex-vivo analyses were performed to distinguish CD45intCD11b+ microglia and CD45hiCD11b+Ly6C+ BM macrophages. Functional studies were also performed.

Materials & Methods:
Young male C57Bl/6 mice were subject to sham surgery or middle cerebral artery occlusion for 90min followed by 72hr or 7d of reperfusion. Ipsilateral hemispheres were harvested from PBS perfused mice and fixed for immunohistological preparation or processed by dissociation into single cell suspensions for use in functional flow cytometry assays.

Results:
Significant microglia cell death occurred by 72hr, and inversely correlated with BM macrophage infiltration. Surviving microglia showed a low rate of proliferation in response to ischemic stress compared to BM macrophages (1% vs. 7%; p<0.01). Peripheral macrophages were the primary source of TNF, while IL-1β was predominately expressed by microglia. Mitochondrial activity was significantly altered in microglia after stroke (p<0.05) and was accompanied by two-fold increases in ROS production. Finally, microglia displayed poor phagocytic potential after stroke compared to infiltrating macrophages (12% vs. 30%; p<0.01).

Discussion:
There is a complex, biphasic macrophage response to stroke injury. The post-acute phase is characterized by widespread microglia activation and dysregulation, whereas the subsequent resolution phase consists of debris clearance in the necrotic core by infiltrating macrophages.
Abstract T P73: Peri Infarct N-Acetylaspartic Acid Predicts White Matter Atrophy After Ischemic Stroke
Authors: Yassi Nawaf , Bivard Andrew , Campbell Bruce C , Parsons Mark W , Donnan Geoffrey A , Desmond Patricia M , Davis Stephen M
Published: March 2022

Objective:
Cerebral volume changes post stroke have recently been described and may correlate with clinical outcome. We aimed to determine whether peri infarct measurement of the neuronal marker N-Acetylaspartic acid (NAA) on Magnetic Resonance Spectroscopy (MRS) predicts progressive cerebral volume change after stroke.

Methods:
11 patients (7 male) with supratentorial ischemic stroke underwent serial MRI within 1 week of onset, and at 1 and 3 months. Imaging was performed on a 3T Siemens Trio scanner. Structural imaging utilized a T1-weighted axial MPRAGE acquisition (1mm slices, TR1.9sec, TE2.82msec). NAA estimation was performed at the baseline scan using single voxel MRS (TE30msec, 3x3x3cm voxels). The voxel was placed in the peri infarct region as determined by assessment of the diffusion weighted image. Quantitative MRS analysis was performed using LCmodel using water referencing. Brain tissue volume, normalized for subject head size, was estimated with SIENAX, part of FSL. Due to anticipated effects of edema on initial cerebral volume, changes in grey, white and total brain volume were assessed as percentage change between the 1 and 3 month scans.

Results:
Mean age was 71yr (IQR 62-79yr). Median baseline NIHSS was 11 (IQR 6-14). Mean baseline grey, white and total brain volume were 713ml (IQR 683-749), 731mL (IQR 721-747) and 1444mL (IQR 1384-1503) respectively. There was a significant correlation between age and baseline grey matter volume (r2=0.73, p=0.001) and total brain volume (r2=0.74, p=0.001). Mean peri infarct NAA concentration was 6.2mM (SD 1.3) compared with 7.0mM (SD 1.2) in the contralateral hemisphere (p=0.09, paired t-test). Mean percentage grey, white and total brain volume changes were 1.2% (IQR -1.8-4.1), 0.4% (IQR -2.2-3.7) and 0.8% (IRQ -1.0-2.6) respectively. There was a significant correlation between baseline NAA in the peri infarct region and change in white matter volume between the 1 and 3 month time points (r2=0.26, p=0.008).

Conclusions:
Estimation of the neuronal marker NAA using MRS may signify varying degrees of neuronal damage after stroke which may correlate with the severity of axonal degeneration and subsequent white matter volume changes. Further validation and correlation with clinical outcomes is required.
Abstract T P78: Remote Ischemic Conditioning (RIC), a Combined Regimen of Per- and Post- Conditionings (RIPerC and RIPostC), Provides Long-term Motor and Cognitive Benefits in Murine Embolic Stroke Model (eMCAO)
Authors: Hoda Md Nasrul , Khan Mohammad B , Wakade Chandramohan G , Ergul Adviye , Fagan Susan C , Hess David C
Published: March 2022

The majority of stroke sufferers need rehabilitation and institutional grade long-term care even after IV-tPA therapy. RIC therapy is easier to perform, safe, promising and ideal for post-stroke rehabilitation. Long-term benefits of RIC have never been reported after eMCAO. Our objective here was to determine if RIC provides long-term behavioral benefits with and without IV-tPA.

Methods:
eMCAO was induced in WT C57/Bl male mice (~6-mo old). Animals were randomized for the treatments (RIC, NO vs. YES; and IV-tPA, NO vs. YES, n=20/group) after eMCAO. Either IV-tPA (10 mg/kg b.wt.) or IV-saline was infused at 4 hours post-eMCAO. RIC was performed non-invasively on the left hind limb at 2, 8 and 24 hours post-eMCAO, followed by every alternate day till day 15. Neurological deficit score (NDS), and adhesive tape test were performed on day 2, 7 and 15 post-stroke to assess the motor function. Cognitive function was assessed by novel object recognition (NOR) test on day 8 and 16 post-stroke.

Results:
RIC improved NDS and sensorimotor functions significantly (p<0.05) on day 2 and 7 with and without IV-tPA, but late IV-tPA alone was not effective. On day 15, there was a trend towards improved motor function in RIC treated groups, which was not significant. However, cognitive function was improved significantly (p<0.05) on day 8 and 16 in RIC-treated groups with and without IV-tPA. IV-tPA alone did not provide any significant improvement in cognition. RIC also improved the survival with and without IV-tPA.

Conclusion:
RIC is a promising therapy for improved motor and cognitive functions during post-stroke rehabilitation and provides survival benefits. Further work is needed to determine the potential of RIC in aged animals and in animals with comorbidities.
Abstract T P80: Correlates of Spleen Volume After Stroke
Authors: Chiu Nina L , Kaiser Brian , Nguyen Y. Vien , Aubin Kimia , Flores Rebeca , Welbourne Susan , Lall Chandana , Cramer Steven C
Published: March 2022

Introduction:
Inflammatory events have a major influence on acute injury and on neural repair after stroke, and may also be important mediators of treatment effects for some cellular therapies. Preclinical studies suggest that splenic events may be important to the evolution of post-stroke inflammation, and that reduced splenic volume may be a useful marker of these events. The current study extended these findings to humans by examining spleen volumes and their clinical correlates in patients admitted for stroke in order to test the hypothesis that splenic volume is related to 4 variables of interest (1) time post-stroke, (2) level of blood lymphocytes, (3) level of blood neutrophils, and (4) volume of cerebral infarct.

METHODS:
This retrospective study examined patients admitted for a new stroke between 2006-2011 at a single institution who also had an abdominal CT scan performed. Clinical data were extracted from medical records. Splenic volume was measured from abdominal CT scan by radiologists with expertise in abdominal imaging. Infarct volumes were calculated from brain CT or MRI.

RESULTS:
A total of 90 patients were identified, 4 of whom had abdominal CT prior to stroke, leaving 86 patients. These 86 had age 66 ± 14 yr (mean ± SD), gender 51M/35F, and infarct volume 51 ± 70 cc. Infarcts were ischemic in 58 (67%), 7 of whom (12%) received tPA, and intracerebral hemorrhage in 28 (33%). Spleen volumes were 225±137 cc, and correlated with gender (M>F, p<0.03), but not with age or stroke subtype. In terms of the variables of interest, splenic volume correlated with % lymphocytes (r=-0.27, p<0.02) and % neutrophils (r=0.23, p<0.04), but not with time post-stroke or infarct volume.

CONCLUSIONS:
Among patients admitted for stroke, a smaller spleen was found in relation to high lymphocyte and lower neutrophil levels in the blood, consistent with prior findings in rodents and in humans. Although the retrospective nature of the current study introduces potential for bias, these results further suggest that splenic events may be important to inflammatory events arising after stroke.
Abstract T P85: Restenosis after Carotid Endarterectomy and Preoperative Carotid Plaque Imaging
Authors: Kobayashi Norikata , Sato Kimitoshi , Yamauchi Keita , Maruyama Daisuke , Ishii Daizo , Morita Kenichi , Satow Tetsu , Kataoka Hiroharu , Iihara Koji
Published: March 2022

Introduction:
The incidence of restenosis after carotid endarterectomy (CEA) and carotid artery stenting (CAS) was reported to be approximately 6% at two years after the procedure in the CREST study. Restenosis after CEA, rather than CAS, was more likely to be related to a recurrence of stroke. The correlation between the plaque composition and restenosis after CEA has been investigated in previous reports, but the relationship between restenosis after CEA and preoperative plaque imaging is still unclear.

Objective:
We investigated the relationship between restenosis after CEA based on the preoperative plaque imaging.

Methods:
One-hundred and eighty-four CEAs were performed from November 2005 to March 2009 in our institution. In this study cohort, we included the 41 cases (40 patients, 37 males, mean age ± SD, 70.7±6.3) who underwent 18F-FDG positron emission tomography (PET) and magnetic resonance (MR) imaging using 3D inversion-recovery -based T1-weighted imaging (magnetization-prepared rapid acquisition gradient-echo [MPRAGE]) before CEA. The signal intensity of the carotid artery plaque on MPRAGE sequences was classified as “high” when the intensity was more than 200% the value of the adjacent muscle. The PET findings were evaluated by the maximum standard uptake value (max SUV) and a high max SUV was defined as >1.74. We included patients who had undergone serial imaging studies (CT angiography; n=36, and/or ultrasonography; n=36) postoperatively. Restenosis was defined as >50% stenosis on a CT angiogram or a >200 cm/sec peak systolic velocity (PSV) on ultrasonography at the treated site.

Results:
Overall, restenosis occurred in three cases (7.3%). A MPRAGE high signal was recognized in 31 cases (76%) and a high maxSUV was noted in 23 cases (56%). All three patients with restenosis had both high MPRAGE and high maxSUV values.

The group with MPRAGE high/maxSUV high (n=18) had a significantly higher incidence of restenosis after CEA than did the other groups (P=0.0420).

Conclusions:
The incidence of restenosis after CEA is suspected to be higher when the plaque consists of a rich necrotic core/intraplaque hemorrhage and a high degree of inflammation.
Abstract T P9: Predictive Value of NIHSS for the Hyperdense Artery Sign
Authors: Guzik Amy K , Raman Rema , Ernstrom Karin , Meyer Dawn M , Rapp Karen S , Meyer Brett C , Hemmen Thomas M
Published: March 2022

Background:
Anecdotally, many use a total NIHSS value to determine need for endovascular involvement in acute ischemic stroke patients. However, no NIHSS value has been shown to be predictive of artery occlusion. We aim to identify an NIHSS threshold that predicts vessel occlusion as measured by hyperdense artery sign

Methods:
The UCSD SPOTRIAS prospectively collected database was analyzed for patients diagnosed with acute ischemic stroke (AIS) who received a noncontrast CT on initial evaluation. Groups with and without hyperdense artery sign were compared via Wilcoxon-rank sum and Fisher’s Exact Test. ROC analysis was conducted to determine AUC and threshold NIHSS to predict artery occlusion. Sensitivity and Specificity, and positive and negative predictive value were calculated.

Results:
Of 1617 acute ischemic stroke patients, hyperdense artery sign was present in 204 (12.6%). The hyperdense artery group had more women (52.9% vs 44%, p=0.02), higher rate of atrial fibrillation (38.2% vs 22.2%, p<0.0001), and lower rate of prior cerebrovascular disease (23.1% vs 31.7%, p=0.016). Mean NIHSS was 17.7 in those with hyperdense artery, compared with 9 in those without (p<0.0001). In ROC analysis, the best NIHSS threshold to predict hyperdense artery was 12.5 with AUC of 77.73% (95% CI 74.57, 80.89), sensitivity of 72.5%, and specificity of 73.7%. Positive Predictive Value was 28.5; Negative Predictive Value was 94.9.

Conclusions:
In our AIS population, a NIHSS cutoff of 12.5 was most predictive of artery occlusion, as measured by hyperdense artery sign. The AUC was only moderate and the PPV low at 28.5%. The NPV, however was high, which indicates that patients with NIHSS less than 12-13 are very unlikely to show hyperdense artery signs. This may guide the decision to consider the need for further vessel imaging and endovascular therapies.
Abstract T P91: Reversion of Cognitive Impairment by Carotid Revascularization in Asymptomatic Carotid Stenosis? A Nonrandomized Controlled Study
Authors: Lin Chun-jen , Chang Feng-Chi , Tu Pei-Chi , Lee I-Hui
Published: March 2022

We previously reported that patients with asymptomatic severe stenosis of extracranial internal carotid artery (ICA) have worse dizziness and poorer cognitive performance than matched controls in association with distributed and long-range brain disconnections. There is currently a lack of evidence whether optimal medical treatment alone or with carotid revascularization could be the best treatment for cognitive impairment in these patients.

We consecutively followed 25 patients with asymptomatic severe stenosis (>70%) of ICA. Sixteen received carotid artery stenting (CAS) and optimal medical treatment and nine received optimal medical treatment alone. All subjects received a battery of neuropsychological tests as well as diffusion tensor imaging and resting-state functional magnetic resonance imaging, and were followed at three months after treatments.

We found that patients receiving CAS (100% success), but not those receiving medical treatment alone, had significant improvements in dizziness scores (P=0.001), immediate recall of verbal memory (P=0.002) and complex visuospatial perception (P=0.007) three month after intervention. The interval changes of whole-brain mean fractional anisotropy of both groups were insignificant, and the analysis of functional connectivity is undergoing.

The results may provide insight into whether the benefits of carotid revascularization, including mitigating thromboembolic events and cognitive impairment, outweigh perioperative risks including functional consequence of microemboli.
Abstract T P94: Association Between Carotid Expansive Remodeling Determined by Long-axis High-resolution MRI and Unstable Clinical Presentation
Authors: Yoshida Kazumichi
Published: March 2022

Background and Purpose:
Accumulating evidence from recent vascular biology studies has demonstrated that not only luminal narrowing but also plaque characteristics have large impact on the risk of ischemic events. The impact of expansive remodeling (ER) in atherosclerotic arterial disease on unstable clinical presentation has been extensively investigated in coronary circulation. The purpose of the present study was to investigate the association between carotid ER determined by MRI and cerebral ischemic events.

Methods:
Among prospectively collected data for patients with carotid artery (CA) stenosis scheduled for carotid endarterectomy (CEA) or carotid stenting, 122 CAs in 119 patients were identified. Excluding 22 CAs (contraindicated for MRI due to pacemaker implantation: 2, near-occlusion: 8, inadequate MRI due to poor image quality: 6, restenosis after CEA or CAS: 6), 100 CAs were finally analyzed in this study. The study included 50 symptomatic (73.6 ± 8.9 years; 6 female; %stenosis, 68.5± 21.3; 34 CEA) and 50 asymptomatic lesions (72.0 ± 5.9 years; 5 female; %stenosis, 79.4 ± 8.85; 15 CEA). ER ratio was calculated by dividing the maximal outside diameter at atherosclerotic plaque near the carotid bulb by the maximal outside diameter of the normal internal CA distal to the plaque with use of long-axis high-resolution MRI.

Results:
In 25 patients with unilateral carotid atherosclerosis, the ER ratio of atherosclerotic CA (1.68±0.40) was significantly greater (p<.01) than that of the normal physiological expansion at a carotid bulb (1.36±0.15). The ER ratio of symptomatic CAs (1.93±0.44) was significantly greater (p<0.0001) than that of asymptomatic CAs (1.63±0.30). When the cutoff value was set as 1.88, sensitivity and specificity were 0.6 and 0.78, respectively. The ER ratio of symptomatic CAs was consistently high regardless of % luminal stenosis.

Conclusions:
ER ratio measured with MRI might help to establish more accurate risk stratification for future cerebral ischemic events.
Abstract W MP101: Differences in tPA Door-to-Needle Time by Patient and Hospital Characteristics
Authors: George Mary G , Tong Xin
Published: March 2022

Background:
Achieving a door-to-needle time (DtN) of less than 60 minutes for providing IV tPA is a quality of care measure endorsed by the National Quality Forum. This study assesses whether differences exist in timely provision of IV tPA in the Paul Coverdell National Acute Stroke Registry (PCNASR).

Methods:
There were 2952 patients from 178 hospitals with acute ischemic stroke (AIS) who received IV tPA in the PCNASR in 2012 available for analysis. Chi-square tests were used to test for comparison of DtN time by weekday vs. weekend (Sat or Sun), daytime (8 AM-6 PM) vs. non-daytime, NIHSS score (<10 vs. ≥10), race (white vs. other), and by calendar quarter. Hospitals were categorized by rates of achieving DtN ≤60 min (≥70%, 50-69%, 40-49%, 30-39%, 1-29%, and 0%) and number of patients treated to assess treatment by time of day, day of week, race, gender, and NIHSS.

Results:
Of 2952 patients with AIS who received IV tPA, 44.8% received IV tPA ≤60 min in 2012 (39.2%, 42.8%, 45.8%, and 51.0% by calendar quarter, p<0.001 for trend). Overall, IV tPA was more likely to be given within 60 minutes during daytime hours, to men, and when NIHSS ≥10. Highest performing hospitals (rates ≥70% in ≤60 min) had no disparities by weekday, time of day, race, or gender. Hospitals achieving DtN in ≤60 min for most patients did so more often for patients with NIHSS score ≥10 compared to those with NIHSS <10. Hospitals treating at least 20 patients per year are more likely to achieve a DtN above 50% compared to those treating less than 20 per year (p<0.001).

Conclusion:
Rates of achieving DtN ≤60 min continue to increase over time. There were no differences in day of week, or race overall, although significant differences in achieving DtN in ≤ 60 min exist by time of day, gender, and number of patients treated annually per hospital. These findings have implications for quality improvement interventions in all hospitals and also based on treatment population size.
Abstract W MP108: Accuracy of Diagnoses in Contemporary Medicare Data: REGARDS Study Linked With Medicare Claims
Authors: Kumamaru Hiraku , Judd Suzanne E , Curtis Jeffrey R , Ramachandran Rekha , Hardy N. Chantelle , Rhodes J. David , Safford Monika M , Kissela Brett , Howard George , Jalbert Jessica J , Brott Thomas G , Setoguchi Soko
Published: March 2022

Background:
Administrative data such as Medicare data are commonly used for health services research and comparative effectiveness studies. These databases are readily available and a good source of long-term data on healthcare utilization and health outcomes in real-world settings. Outcomes are captured using diagnostic codes, but the evidence on the validity of these codes is scarce in contemporary Medicare data.

Methods:
We linked the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study data using SSN, date of birth and sex to 2003-2009 Medicare claims. In addition to the events captured by REGARDS phone interviews, medical charts were pursued for Medicare-identified strokes not previously identified in REGRADS. Events were adjudicated by stroke specialists using the retrieved medical charts. Using all the adjudicated strokes as gold standard, we calculated the sensitivity, specificity, PPV and NPV of inpatient stroke algorithms with ICD-9-CM codes [430, 431, 433.x1, 434.x1, 436] in the primary discharge diagnosis.

Results:
We successfully linked 15,089 REGARDS participants with mean age of 69.3, 52% female and 37% Black. We adjudicated 457 strokes, of which 48 were identified by claims only and not by interviews. The tested algorithms had high specificity (99.8-100%), PPV (88.6-90.5%) and NPV (98.9-99.9%), but low sensitivity (58.6-67.4%) (Table).

Conclusions:
High specificity and PPV of our algorithms to identify strokes in contemporary Medicare populations support their use in etiological and comparative effectiveness studies. While our inpatient Medicare algorithms identified 12% extra cases of strokes, their usefulness for estimating stroke incidence or related healthcare utilizations is limited by their low sensitivity. Linking cohorts to Medicare data is feasible and should be considered to increase the completeness of follow-up. Further studies are needed to evaluate more sensitive Medicare algorithms.
Abstract W MP11: Post Stroke Emotional Dysfunction and Fatigue Are Related to Tryptophan Hydroxylase 2 Polymorphsis
Authors: Choi-Kwon Smi , Ko Mi Hye , Choi Sunyoung , Kim J.s.
Published: March 2022

Background and Purpose:
Emotional dysfunction is a common complication after stroke. Despite reports on serotonergic involvement in the etiology post stroke emotional dysfunction (PSED) and post stroke fatigue (PSF), the role of the TPH1 and TPH2 gene responsible for 5-HT synthesis in PSED and PSF requires analysis. The aim of this study was to investigate the association between different genetic variants of the Tryptophan Hydroxylase (TPH) 1 and TPH2 gene and PSED and PSF at 3 months post- stroke.

Method:
TPH1 A218C and TPH2 SNPs, rs4641528 and rs10879355 genotyping were performed from genomic DNA which was collected and stored previously from 373 stroke patients. The potential association between TPH1 and TPH2 polymorphisms and post-stroke depression (PSD), post-stroke emotional incontinence (PSEI), and PSF was investigated.

Results:
PSD, PSEI, and PSF were present in 17.2%, 10.7%, and 44.0% at 3 months post-stroke. Among the patients, 10 (2.7%) had all three PSEDs (PSD, PSEI, and PSF), 37 (9.9%) had two of the three, and 119 (31.9%) had only one among PSD, PSEI, and PSF at 3 months post-stroke.There were no significant differences in the TPH1 A218C genotype or allele frequencies between the patients with PSD, PSEI, or PSF and those without them at 3 months post-stroke. TPH2 SNP rs10879355 was associated with post-stroke fatigue (
p
<0.01) at 3 months post-stroke, whereas TPH2 SNP rs4641528 was associated PSD (
p
=0.018) and PSEI (
p
=0.049).

Conclusions:
Our results suggested that TPH2 SNPs may have an important effect on PSED and PSF at 3 months post-stroke, but the TPH1 A218C polymorphism plays no significant role in the pathogenesis and clinical symptomatology of PSED and PSF.