bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 46: Outcomes of Thrombolysis for In-hospital Stroke: A Population-Based Study of US Hospitals
Authors: Moradiya Yogesh , Levine Steven R
Published: July 2021

Background:
In-hospital stroke (IHS) may differ from out-of-hospital stroke (OHS) in terms of mechanism, risk factors and outcomes.

Objective/Hypothesis:
We compared IHS and OHS treated with systemic or intra-arterial thrombolysis from a large national cohort in a cross-sectional study to further clarify these differences. Our hypothesis was that there would be poorer patient outcomes associated with IHS than OHS.

Methods:
Nationwide inpatient sample (NIS) for years 2005-2009 was searched for stroke cases treated with thrombolysis by using International Classification of Diseases-9 codes. Patients treated on the day of admission were classified as OHS. Primary outcome measures were inpatient mortality and functional independence at discharge as indicated by discharge to home (self-care). Secondary outcomes included intracranial hemorrhage (ICH), GI bleeding, tracheostomy and gastrostomy tube placement. IHS as an independent predictor of outcomes was studied using multivariate logistic regression.

Results:
IHS comprised of 1,054 (11.3%) cases of all (N=9,353) thrombolysed ischemic strokes. IHS was associated with higher co-morbidity profile and higher rates of acute medical conditions. In unadjusted analyses, IHS had higher inpatient mortality (18.8% vs. 10.9%, p<0.001) and lower rate of functional independence at discharge (21.7 vs. 28.6%, p<0.001). While IHS had higher rates of GI bleeding, tracheostomy and gastrostomy, the rate of ICH in IHS was similar to that of OHS (4.6% vs. 4.8%, p=0.807). After controlling for demographics, hospital characteristics and co-morbidities, inpatient mortality (adj. OR:1.82; 95% CI:1.53-2.16, p<0.001) and favorable discharge outcome (adj. OR:0.80; 95% CI:0.68-0.94, p=0.007)) remained significantly worse in IHS while the rate of ICH (adj. OR:0.91; 95% CI:0.67-1.23) remained similar to that of OHS.

Conclusions:
Thrombolysis in IHS is associated with worse outcomes and higher rates of inpatient medical complications compared to OHS, likely due to their higher co-morbidities and additional medical reasons for hospital admission. In spite of presumed higher bleeding risk in IHS, thrombolytic use is not associated with higher rate of ICH among IHS.
Abstract 5: Management Of Intravenous tPA In Non-ICU Environments: Safety, Clinical Outcome, And Cost Savings
Authors: Coleman Kisha C , Palazzo Paola , Shahripour Reza B , Brooks Amy L , Cronin Mary A , Sands Kara A , Lyerly Michael J , Sisson April , Houston Thomas , Rawal Pawan , Alvi Muhammad , Kapoor Niren , Albright Karen C , Boehme Amelia K , Alexandrov Andrei V , Alexandrov Anne W
Published: July 2021

Background:
Administration of IV tPA has traditionally necessitated admission to an ICU solely for monitoring, with relatively no need for extensive critical care services. Stroke Units that are capable of monitoring IV tPA patients have been proposed to reduce ICU use, but limited data exist that demonstrate safety. We report the largest series of non-ICU managed tPA cases in relation to safety and discharge outcomes.

Methods:
Consecutive cases admitted to our intermediate-level Stroke Unit spanning 2009-2011 were assembled. Unit capabilities include IV tPA management with nicardipine infusion for blood pressure control as needed, non-invasive or direct central/arterial line and cardiac monitoring, and BiPAP ventilation. Stroke Unit nurses underwent extensive orientation and participate in NET SMART Junior for continuing education. Overall sICH, and drip/ship sICH (parenchymal hemorrhage in combination with > 4 point increase on the NIHSS), systemic hemorrhage, and tPA related death rates were calculated, along with discharge mRS and total ICU cost savings per day.

Results:
A total of 302 Stroke Unit admissions for intravenous tPA occurred over the 3 year period, while another 31 (10%) were excluded due to critical care admission for systemic hemodynamic or pulmonary instability. Nicardipine infusions were used in 9 (10.5%) Stroke Unit tPA cases in 2009, 10 (9%) in 2010, and 14 (13%) in 2011. Overall sICH rate was 3.3% (n=10) and systemic hemorrhage rate was 2.9% (n=9) with 5 of these (56%) requiring transfusion. Estimated cost savings in total for this 3 year period was $362,400 for “avoided” ICU days.

Conclusions:
Intravenous tPA patients may be safely managed on non-ICU Stroke Units when nurses undergo extensive education to ensure clinical competence. Use of the ICU solely for management of tPA monitoring needs may constitute significant overuse of system resources at an expense that is not associated with additional safety benefit.
Abstract 58: Rates Of Postoperative Stroke, Cardiac Complication And Mortality In Patients Undergoing Intracranial Stent Placement As Part Of A Clinical Trial Versus Those Treated Outside A Clinical Trial
Authors: Siddiq Farhan , Adil Malik M , Qureshi Adnan I
Published: July 2021

Background:
The pre-maturely discontinued Stenting versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial demonstrated lack of benefit of intracranial stent placement due to high rates of immediate post procedure complications. The rates of complications were higher than those reported previously raising the question whether such results were representative of intracranial stent placement in actual routine practice.

Objective:
To ascertain and compare the rate of outcomes between patients who underwent intracranial stent placement within and outside clinical trials.

Materials/Methods:
Using the Nationwide Inpatient Sample (NIS) from 2008 to 2010, patients with cerebral ischemic events who underwent intracranial stent placement were identified using ICD-9 diagnosis and procedure codes. Patients were divided into those who received intracranial stent placement as part of the clinical trial and those who were treated outside any trial. The postoperative mortality, stroke and cardiac complications were primary endpoints.

Results:
A total of 3447 patient underwent intracranial stent placement, 223 patients (6.5%) were enrolled in a clinical trial. Patients who received intracranial stent placement as part of the clinical trial were significantly younger (65±10 versus 68±13 years, p=0.008). Both groups did not differ in terms of gender, race and ethnicity and medical co-morbidities. Mean length of stay was longer in patients treated outside a clinical trial (9.1±11 versus 5.1±4, p<0.0001). The rate of composite endpoint of postoperative mortality (9.6% versus 4.5%), postoperative stroke (4.6% versus 0%), and cardiac complications (1% versus 0%) was significantly higher in patients treated with intracranial stent placement outside clinical trial compared with those treated within clinical trials (14.2% versus 4.5%, p = 0.04).

Conclusions:
Patients who undergo intracranial stent placement outside a clinical trial have higher rates of postoperative stroke, cardiac complication and mortality. Such results support those of the SAMMPRIS trial and the need for restricting these procedures to selected patients and specialized centers with high experience.
Abstract 60: Synthesis Expansion: Randomized Trial On Primary Endovascular Treatment Vs. Standard Intravenous Recombinant Tissue Plasminogen Activator For Acute Ischemic Stroke
Authors: Ciccone Alfonso , Valvassori Luca , Boccardi Edoardo , Sterzi Roberto ,   Synthesis Investigators
Published: July 2021

Background:
As compared with systemic i.v. thrombolytic therapy, primary endovascular treatment results in a higher rate of patency of the ischemic stroke-related cerebral artery. However, the comparative clinical efficacy of the two approaches has not been carefully studied.

Methods:
We randomly assigned a total of 362 patients with acute ischemic stroke seen within 4.5 h from symptoms onset to endovascular treatment (i.e., intra-arterial thrombolysis with recombinant tissue plasminogen activator - t-PA - if necessary, associated to or substituted by mechanical clot disruption and/or retrieval) or i.v. t-PA administered according to EU labeling. The purpose of the study was to determine the proportion of independent survivors at three months. Safety endpoints included symptomatic intracranial hemorrhage, death and other serious adverse events.

Results:
A total of 181 patients were assigned to undergo endovascular treatment, and 181 to receive i.v. t-PA. Median time from stroke onset to start to treatment was 3 h 45 min for endovascular treatment (range: 1 h 30 min to 5 h 55 min) and 2 h 45 min (range: 55 min to 4 h 30 min) for i.v. t-PA (p=0.002). All the randomized patients were assessed at 3 months and analyzed. We will present analyses comparing the effect of endovascular treatment with i.v. t-PA on a) the primary outcome (proportion of patients alive and independent at 3 months as assessed by the modified Rankin scale) adjusted for key covariates, b) death from any cause within 3 months, c) events within 7 days: fatal and non fatal symptomatic intracranial hemorrhages, fatal and non fatal neurological deterioration attributed to brain swelling from the initial ischemic stroke, fatal and non fatal neurological deterioration not attributed to swelling or intracranial hemorrhage, fatal and non fatal recurrent ischemic stroke, death from any cause.

Conclusions:
Data from the trial will provide new evidence on the balance of risk and benefit of endovascular treatment, as compared to systemic thrombolysis, among patients with acute ischemic stroke.
Abstract 64: Mechanism Of Carotid Plaque Vulnerability: Associations Of Pro-and Anti-inflammatory Molecules
Authors: SHINDO Akihiro , Tanemura Hiroshi , Yata Kenichiro , Asakura Fumio , Toma Naoki , Sakaida Hiroshi , Hamada Kazuhide , Fujisawa Takao , Taki Waro , Tomimoto Hidekazu
Published: July 2021

Background:
Inflammation plays an important role in the development, progression, and rupture of carotid plaques. We examined the relationship between plaque vulnerability and inflammatory molecules using blood samples and histological specimens.

Methods:
We examined 58 patients with symptomatic or asymptomatic carotid stenosis, among which 41 underwent carotid artery stenting (CAS) and 17 underwent carotid endarterectomy (CEA). All of these patients were recruited in Mie University Hospital from Sept. 2009 to Mar. 2012 and underwent carotid plaque imaging with MRI. In the 41 patients with CAS, blood samples were obtained in the femoral artery as controls and in the carotid artery just before and after the operation. Emboli attached to the distal protection devices in CAS, or resected tissues after CEA were embedded in paraffin. The serum concentrations of IL-6, IL-10, E-selectin, adiponectin, hs-CRP and pentraxin 3 (PTX3) levels were measured by ELISA. Paraffin-embedded tissues were subjected to histopathologic and immunohistochemical analysis on IL-6, IL-10, E-selectin, PTX3.

Results:
The patients with CAS were classified to 22 with stable plaque (stable group) and 19 with vulnerable plaque (vulnerable group). The values of IL-6, E-selectin, hs-CRP and PTX3 in the vulnerable group were higher than those in the stable group, whereas adiponectin and IL-10 were decreased in the vulnerable group as compared to the stable group. The values of PTX3 in the control and intracarotid samples before and after CAS were higher from the vulnerable group than those from the stable group. Pathologically, IL-6 was immunostained in the vulnerable plaques with infiltration of inflammatory cells, and PTX3 was expressed in the endothelial and perivascular cells in the unstable plaques.

Conclusions:
The vulnerability of carotid plaques was modulated by upregulation of pro-inflammatory factors and downregulation of anti-inflammatory ones. In addition, PTX3 may be a novel determinant for plaque vulnerability.
Abstract 65: Malignant Emboli On Trans Cranial Doppler During Carotid Stenting Predict Post Procedural DWI Lesions And Are Most Common During Stent And Distal Protection Device Deployment
Authors: Almekhlafi Mohammed A , Bal Simerpeet , Stephenson Caroline , Stewart Eileen , Mishra Sachin , Nambiar Vivek , Menon Bijoy , Hill Michael D , Demchuk Andrew M , Goyal Mayank
Published: July 2021

BACKGOUND:
We evaluated the safety of the steps during carotid stenting.

METHODS:
This was a prospective single-arm study. Cases were monitored by TCD during the stenting procedure. The time of each of 11 steps was recorded and noted during TCD interpretation. Post stenting MRI was done in all patients. Emboli on TCD were classified based on the relative energy index of microemboli (REIM) method into microemboli (REIM ≤ 1) or malignant (REIM >1). Medians were compared using Mann-Whitney test. A negative binomial model was used to investigate the predictive value of TCD findings on new DWI hits.

RESULTS:
We enrolled 30 subjects. The median age was 70.5 years and 23.3% were asymptomatic. The median count of embolic signals was 212.5 (108 microemboli, 80 malignant). Stent deployment had the highest median count 58 (31 microemboli, 20 malignant) followed by protection device deployment 30 (21 microemboli, 10 malignant, (p value 0.0006)) “Figure”. On post stenting MRI, 80% had new DWI hits. The median DWI count was 4 (range 0-33). The median volume of DWI hits was 0.4 ml (range 0 - 6.1 ml). 63% of patients had a total volume under 1 ml. Only 2 patients (6.7%) had new deficits post stenting. The median DWI volume in those patients was 3.0 ml compared to 0.6 ml in asymptomatic cases (p 0.037). Median emboli count in those with vs. without new deficits was not different (p 0.87) Total TCD emboli count did not predict DWI hits, adjusting for age and symptoms’ status (p 0.25). Malignant emboli predicted new DWI hits (p 0.044). For every malignant embolus, the expected count of DWI hits increases by 1% (CI95 0-2%). There was no relation between total or malignant emboli with the DWI volume.

CONCLUSIONS:
In this prospective study, we observed a high incidence of emboli on TCD during stenting, especially when stent and protection device were deployed. Most patients developed new DWI hits but only 6.7% had new deficits. The combined DWI volume was less than 1.0 ml in most cases. Only malignant emboli predicted new DWI hits.
Abstract 7: The Impact of Post-Stroke Rehabilitation on 2-year Healthcare Costs in Ontario, Canada: Can Rehabilitation Save Us Money?
Authors: Meyer Matthew J , O’Callaghan Christina , Kelloway Linda , Hall Ruth , Li Shudong , Fang Jiming , Bayley Mark , Reeves Mathew , Teasell Robert
Published: July 2021

Introduction:
A substantial evidence base supports the positive benefits of post-stroke rehabilitation. The objective of this study was to evaluate the impact of inpatient rehabilitation on 2-year healthcare costs in Ontario, Canada.

Methods:
Acute patient data was drawn from the 2004 and 2008 Ontario Stroke Audits for 3439 patients with ischemic stroke discharged alive from an acute care hospital. Patients were assigned a propensity score using 15 demographic and clinical variables. Patients admitted to inpatient rehabilitation (Rehab) were then matched one-to-one with a patient not admitted to inpatient rehabilitation (No-Rehab) using propensity score and modified Rankin Scale (mRS) score. The cohort was stratified by mRS into three groups (mRS 0-2,3,4-5) and comparisons were drawn between Rehab and No-Rehab patients for 2-year mortality and government-billed healthcare costs (hospital, home care, and drug benefit costs).

Results:
No difference in mortality was noted between Rehab and No-Rehab patients with discharge mRS scores of 0-2 (p=0.39), but Rehab patients cost an average of $33,056 more over the 2 years (p<0.001) and $63 more per day survived (p<0.0001). Among patients with mRS 3, Rehab patients were significantly more likely to survive to 2 years (p<0.001), and cost an average of $22,394 more up to 2 years (p<0.001) and $5 more per day survived (p<0.0001). Rehab patients with mRS scores of 4-5 were significantly more likely to survive to 2-years (p=0.01), but cost an average of $6,607 less (p=0.24) and $29 less per day survived (p=0.07).

Conclusions:
Findings suggest that disability level plays an important role in the cost-effectiveness of inpatient rehabilitation. Among patients with milder disability, inpatient rehabilitation is significantly more costly with no demonstrated benefit in 2-year mortality. However among patients with moderate to severe disability, inpatient rehabilitation significantly reduces mortality rates and may actually reduce overall healthcare spending up to 2-years post stroke.
Abstract 74: The Epidemiology of Childhood Stroke in Southern England: A Prospective Study using Multiple Sources of Case Ascertainment
Authors: Mallick Andrew A , Ganesan Vijeya , Kirkham Fenella J , Fallon Penny , Hedderly Tammy , McShane Tony , Parker Alisdair P , Wassmer Evangeline , Wraige Elizabeth , O’Callaghan Finbar J
Published: July 2021

Background:
Epidemiological data are vital to quantify the scale of disease and can provide insights into aetiological factors.

Objective:
To describe the epidemiology of childhood stroke in southern England.

Methods:
Children (>28 days to <16 years) residing in southern England (5.99 million children) who had arterial ischemic stroke (AIS), cerebral sinovenous thrombosis with venous infarction (CSVT) and hemorrhagic stroke (HS) between July 2008 and June 2009 were identified. Multiple sources including pediatric neurologists, pediatricians, neurosurgeons, radiologists, physiotherapists, a national intensive care audit system, and parents notified cases.

Results:
153 cases of stroke were identified (96 cases of AIS, 14 cases of CSVT and 43 cases of HS). The incidence for overall stroke was 2.56 per 100,000 person years (95% CI 2.15 - 2.96). The age distribution is shown in Figure 1. There was no difference between males and females in the risk of ischemic (AIS and CSVT) stroke (RR=1.06, p=0.75), HS (RR=1.46, p=0.22) or overall stroke (RR=1.16, p=0.36). Compared to Whites the relative risk of ischaemic stroke was higher for Asians (RR=2.35, p=0.001) and Blacks (RR=2.52, p=0.003). There was no increased risk of HS for Asians (RR=0.84, p=0.77) or Blacks (RR=1.39, p=0.58).

Conclusions:
The incidence of childhood stroke found by this study is higher than previously found in the UK. This is the first study to show disparities in the risk of childhood stroke between ethnic groups in Europe. Although an increased risk for males is commonly reported a number of recent population based studies have found no gender disparity.
Abstract 90: Diabetes Impairs Post-stroke Cerebrovascular Plasticity And Long-term Functional Recovery.
Authors: Prakash Roshini , Li Weiguo , Qu Zhi , Fagan Susan C , Ergul Adviye
Published: July 2021

Background:
Stroke associated with pre-existing diabetes worsens ischemic injury and impairs recovery. We have previously shown that type-2-diabetic rats subjected to cerebral ischemic reperfusion injury develop hemorrhagic transformation (HT) and greater neurological deficits. These diabetic rats also exhibit enhanced dysfunctional cerebral neovascularization that increases the risk of bleeding post-stroke. However, our knowledge of vascular and functional plasticity during the recovery phase of diabetic stroke is limited. This study tested the hypothesis that post-stroke neovascularization is impaired in diabetes and this is associated with poor sensorimotor and cognitive outcomes.

Methods:
Reparative neovascularization was assessed in the lesional and non-lesional areas in diabetic rats after 14 days of ischemic reperfusion injury. 3-dimensional reconstruction of the FITC stained vasculature were obtained by confocal microscopy and stereological parameters including vascular volume and surface area were measured. Astrogliosis was also determined by GFAP staining. The relative rates of sensorimotor recovery, cognitive decline and spontaneous activity were assessed.

Results:
Diabetes impairs reparative neovascularization in the lesional areas compared to control rats. Astroglial swelling and reactivity was pronounced in diabetic stroke compared to control stroke. Rate of sensorimotor recovery was significantly slower in diabetic stroke compared to the controls. Diabetes also exacerbated anxiety-like symptoms and cognitive decline post-stroke relative to control.

Conclusion:
Diabetes impairs post-stroke reparative neovascularization and impedes functional recovery. The impact of glycemic control on poor recovery in this critical period needs to be tested. N=6-8
*
p≤ 0.05,
**
p≤ 0.005
Abstract NS12: Inpatient Stroke Code, an Accurate Activation
Authors: Clarkson Katherine , Nolan Scot
Published: July 2021

Background:
In 2011, it was noted by the hospital that multiple stroke code activations were occurring on inpatients that did not have signs of focal neurological deficit, or stroke. In a six-month retrospective review, a total of 32 inpatient stroke codes were identified. Of these, only 8.6% of patients had a focal neurologic deficit. The remainder had other symptoms, such as alteration in level of consciousness. In addition to the potential harmful effects of unnecessary testing, cost was also considered. A code stroke protocol testing and staffing accumulates approximately $358.00 in cost during the first hour. This is in comparison to the rapid response team activation, which incurs $79.00 during the first hour.

Purpose:
For inpatient stroke codes, does a floor RN activated RRT, directly followed by an ICU RN activated stroke code, if applicable, reduce the number of inappropriate inpatient stroke code activations?

Methods:
Following literature review, it was decided by the Stroke Code Team to move having an initial RRT activation by the floor RN who suspects her patient may be having an acute stroke. Then, as part of the RRT, an ICU RN would arrive at the bedside and evaluate the patient. Following assessment, and if it was felt appropriate, a stroke code would be initiated.

Results:
A 30-day period was closely examined for potential impact. During this period, 11 Stroke Codes were identified. Of these, 3 stroke codes were activated without the RRT and did not follow the new protocol. Of the remaining 8 RRT activations, 6 lead to stroke codes. Of these, 2 of 6 (33.3%) had an accurate diagnosis of acute onset stroke. This indicates a 25% decrease in the number of inaccurate stroke code.

Conclusion:
Since the RRT activation was an additional step, a primary concern with the change in protocol was the delay in treatment of IV tPA. It did not result in a delay in care, and the time from RRT activation to stroke code team arrival was less than 4 minutes. If the initial RRT activation in place of stroke code was to continue at this pace, an approximate annualized savings of at least $10,800.00 could be achieved. Further data analysis and study is warranted in order to determine long-term cost avoidance and implications to the change in protocol.
Abstract NS2: A Comparison of IV t-PA Administration between Critical Access Hospitals and a Primary Stroke Center
Authors: Brethour Mary K , Kesler Rebecca , Landers Dee , Turner Teresa
Published: July 2021

Background:
Critical access hospitals (CAH) and small community hospitals increase the availability of intravenous tissue plasminogen activator (IV t-PA) in rural areas. However, are their quality control measures and outcomes comparable to a Primary Stroke Center (PSC) functioning as a hub hospital? A comparison of quality control and protocol deviations, as well as outcome measures, of t-PA administered at CAHs to a PSC hospital was undertaken.

Methods:
A retrospective chart review of 35 cases of IV t-PA administered in 2012 was completed, including age and gender, initial NIHSS, door to needle time (DTN), protocol deviations, the presence of hemorrhagic transformation, and discharge destinations.

Results:
A total of 35 patients received IV t-PA_21 at CAHs and 14 at the PSC hospital in the first 7 months of 2012. The mean age of the CAH patients was 59.33 + 13.8 with 59% female; the mean age of the patients at the PSC hospital was 67.21 + 13.1 with 35% female. The initial NIHSS was lower, but not statistically significant (p=0.074) at CAHs_9.94 compared with the PSC hospital NIHSS of 14.31. The mean DTN time was significantly (p=0.026) longer at the CAHs--104.12 minutes, compared to 64.71 minutes at the PSC hospital, with only 23% of patients receiving IV t-PA within the goal of 60 minutes. At the PSC hospital 36% of patients received t-PA within 60 minutes. The hemorrhagic transformation rate at the CAHs was 18% compared with 7% at the PSC hospital. Protocol deviations were similar between the 2 populations. Discharge destinations varied between CAHs and the PSC hospital with 30% of stroke patients from the CAHs discharged home and 24.2% transferred to in-patient rehab; compared with 15.2% from the PSC discharged home and 6.1% to rehab.

Discussion:
CAHs were designed to function as an integral link to provide health care to rural communities. The communities served benefit when CAHs collaborate with Regional referral centers. The significant difference in IV t-PA administration between CAHs and a PSC hospital demonstrate the on-going need for collaboration and education.
Abstract TMP1: Infarct Location And Volumes As Predictors Of Outcome After Endovascular Recanalization Of Basilar Artery Occlusion
Authors: Jadhav Ashutosh P , Nanduri Sunanda , Starr Matthew , Aghaebrahim Amin , Zaidi Syed , Jumaa Mohammad , Linares Guillermo , Reddy Vivek , Hammer Maxim , Jankowitz Brian , Wechsler Lawrence , Jovin Tudor
Published: July 2021

Background and Purpose:
Prognostic information after endovascular recanalization of basilar artery occlusion is important for guiding aggressiveness of subsequent care. While final infarct volumes have been shown to correlate with outcomes in anterior circulation strokes, no such relationship has been described in basilar artery occlusions. We sought to determine the relationship between the volume of final infarction, location of infarction and outcome of clinical course in patients treated with endovascular therapy for basilar artery occlusion at our institution.

Methods:
A retrospective review of our prospectively maintained endovascular stroke database identified 103 patients of which 59 patients underwent post treatment MRI. Automated software was used to measure infarct volume.

Results:
Patients included in the study had the following features: mean age 61, mean NIHSS 20, female 24%. Successful recanalization (TIMI 2/3) occurred in 53/59 patients (90%). Infarcts were divided into topographic regions (see Table). Good outcomes (mRS 0-2 at 3 months) were achieved in 32% of patients. 71% of patients with no brainstem infarct had a good outcome (p=0.03). 46% of patients with no thalamic infarct had a good outcome (p=0.049). In multivariate analysis, independent predictors of good outcomes were brainstem infarct volume (OR 0.25, 95% CI 0.11-0.61, p=0.002) and age (OR 0.84, CI 0.74-.91, p=0.0018). Patients with good outcomes had a mean brainstem infarct volume of 1.45 cc, while patients with poor outcomes had a mean brainstem infarct volume of 6 cc (p=0.002).

Conclusions:
Rate of good outcomes after recanalization of basilar artery occlusion is 32%. Presence and volume of brainstem infarct, presence of thalamic infarct and patient age are the strongest predictors of outcome. Further studies will address whether these parameters can be used prospectively in prognosticating outcomes after basilar artery occlusive disease.
Abstract TMP120: Endovascular Balloon-Assisted Embolization of Intracranial Arteriovenous Malformations Using Dual Lumen Co-Axial Balloon Microcatheters and Onyx: Initial Experience.
Authors: Jagadeesan Bharathi D , Grigoryan Mikayel , Hassan Ameer E , Grande Andrew W , Tummala Ramachandra P
Published: July 2021

Background:
Ethylene Vinyl alcohol co-polymer (Onyx) is widely used for embolization of intracranial arteriovenous malformations. Traditional catheter based techniques for Onyx infiltration may be associated with reflux of Onyx resulting in cathteter retention, vessel rupture or reflux into en-passage arteries. Balloon assisted Onyx embolization may eliminate some of these problems encountered with traditional catheter based techniques. Herein, we report our initial experience in performing balloon assisted AVM embolization for brain AVMs and dural AVFs using the new Scepter-C and Scepter-XC co- axial dual lumen balloon microcatheters.

Methods:
Balloon-assisted trans-arterial embolization was carried out in a series of six patients (5 with brain AVMs, one with a dural AVF ) using Onyx delivered through the lumen of Scepter-C or Scepter XC co-axial balloon microcatheters. Following initial balloon-catheter navigation into a feeding artery as close to the nidus of the malformation as possible, and subsequent balloon inflation, embolization was performed using Onyx 18 or Onyx 34 or both. The balloon was delated and removed once adequate embolization had been achieved.

Results:
A total of ten embolization sessions were performed via fifteen arterial feeders in these five patients. In one out of fifteen vessels (7%), there was a quickly controlled arterial perforation from balloon inflation, in all others embolization goals for each session were successfully achieved with no adverse events.

Conclusion:
We found that the balloon microcatheters showed excellent navigability and there were no problems with retrieval or repeated inflation and deflation of the balloons. Using this technique, we were able to avoid the need for formation of a proximal Onyx plug and its associated risks. Additionally, fluoroscopy and procedural times seemed lower with this technique compared to conventional embolization methods.
Abstract TMP13: Baseline DWMRI Characteristics In Patients With Cryptogenic Stroke And Patent Foramen Ovale: Results From The Closure I Trial
Authors: Jung Richard , Kim Benny , Massaro Joseph , Furlan Anthony J
Published: July 2021

Background:
Cryptogenic stroke may have several etiologies including paradoxical embolism through a patent foramen ovale (PFO). A cardiac source of embolism may be suggested by multiple infarcts, sometimes hemorrhagic, in different vascular distributions or a cortical wedge shaped infarct. We report the baseline diffusion weighted MRI (DWMRI) characteristics in patients with cryptogenic stroke and a patent foramen ovale (PFO) from the CLOSURE I trial.

Methods:
CLOSURE I compared device closure versus medical therapy for secondary prevention in patients with cryptogenic TIA or stroke and a PFO. Of 909 patients randomized, 562 patients demonstrated acute infarcts on baseline DWMRI and are included in this analysis. Multivariate proportional hazard Cox regression compared imaging subgroups with remaining randomized patients

Results:
Single infarcts were found in 62% of patients. Of these, 61% were anterior circulation, 30% posterior, and 8.5% were of uncertain territory. Of the anterior circulation infarcts, 40% were cortical, 36% subcortical, and 24% affected both the cortical and subcortical regions. Of the posterior circulation infarcts, 45% were thalamic or cerebellar. Of 562 patients, 18.5% had a single subcortical lesion <1.5cm in diameter and met the radiological definition of an acute lacunar infarct. Multiple infarcts were found in 38%. Infarcts in a single vascular territory were found in 23%, often in the anterior circulation (66%). Infarcts in multiple vascular territories were found in 15%. Hemorrhagic infarction was present in 9%. Adjusting for patient characteristics, no significant difference in 2 year rate of TIA, stroke or death was found compared to remaining randomized patients.

Discussion:
The specificity of infarct patterns for embolism in patients with cryptogenic stroke and a PFO is uncertain. We found no significant relationship between lacunar or subcortical infarction and the risk of recurrent TIA or stroke. Baseline infarct patterns on DWMRI in patients with cryptogenic stroke and PFO may not be useful in predicting recurrent stroke risk or determining best prevention therapy.
Abstract TMP14: Masked Smoothing for Computed Tomography Perfusion Imaging
Authors: Wack David , Snyder Kenneth , Seals Kevin , Natarajan Sabareesh , Fisher Jason , Creighton Terrance , Eller Jorge , Siddiqui Adnan
Published: July 2021

Objective:
CT perfusion imaging is characterized by a high contrast ratio between different structure types. This facilitates the segmentation of an image into different classes, such as tissue and vasculature. However, grey and white matter tissue regions have relatively low values and can suffer from poor signal to noise ratios. While smoothing can improve the image quality of brain parenchyma, the inclusion of high contrast vascular voxels skews the dataset. It is thus desirable to smooth the tissue voxels independently from other voxel types, as has been implemented previously using mean filters with small kernel sizes. Bilateral filters have also been proposed, allowing a varying influence of neighboring voxels based on the similarity of the voxel’s intensity. These filters are orders of magnitude slower, however, as the smoothing kernel is not directly separable. A separable kernel can be applied to an image volume as 3 implementations of a 1D filter. A kernel of size 50x50x50, for example, is applied to a volume with 3x50 (150) multiplications per voxel if it is separable and 50^3 (125,000) if it is not. Our approach, which applies smoothing to tissue voxels without including neighboring vessel voxels in the kernel, can be calculated by dividing the results of just two applications of a separable kernel.

Methods:
We compare our Masked Smoothing method to alternative Gaussian smoothing approaches using an unaltered image and an image where vascular voxels have been set to zero. The base image size is 512x512x320x19.

Results:
Using simulations we demonstrate that Masked Smoothing does not bias the underlying tissue value, whereas the other smoothing methods cause significant bias. Furthermore, using actual CT perfusion data, we demonstrate a significant difference in the calculated cerebral blood flow and cerebral blood volume based on the smoothing method used.

Conclusions:
Given the enormous datasets inherent to CT perfusion and the need for rapid clinical evaluation, it is crucial to develop a smoothing method that prevents the bias of tissue values from neighboring vessels and executes rapidly. Our novel smoothing method achieves both goals.
Abstract TMP27: Aneurysm Morphology And Prediction Of Rupture In Unruptured Intracranial Aneurysms
Authors: Brown Robert D , Torner James C , Capuano Ana W , Raghavan Madhavan L , Mocco J , Piepgras David G , Meissner Irene , Huston John ,   International Study of Unruptured Intracranial Aneurysms Investigators
Published: July 2021

Introduction:
There is ongoing debate regarding the rupture risk of an unruptured intracranial aneurysm (UIA), and the predictors of rupture.

Hypothesis:
There are aneurysm morphology characteristics which predict rupture in patients with an UIA. The purpose of this analysis was to assess for such characteristics utilizing the International Study of Unruptured Intracranial Aneurysms (ISUIA) cohort.

Methods:
Patients were entered prospectively at 61 centers. Patients must have had at least one UIA, which may or may not have been symptomatic. Patients were followed for a median of 9 years and all potential hemorrhages were carefully adjudicated. A case-control design was used. The cases were 57 patients with aneurysmal rupture during followup for whom detailed radiology data were available from arteriography. Controls were 198 size- (+/- 2 mm maximum diameter) and location- (parent artery) matched patients without rupture during followup. Numerous aneurysm morphology characteristics were assessed on arteriogram review. Multivariable condition logistic regression modeling was performed.

Results:
A total of 57 cases and 198 controls were included. Most (76%) of the 255 cases were women, and 20% had a prior history of SAH from some other aneurysm. There were no differences between cases and controls in aneurysm maximum diameter, aneurysm location, patient age, gender, reason for presentation, or prior medical history. Multivariate analysis identified that only perpendicular height of the aneurysm--the measurement of the aneurysm height at a perpendicular to the center of the aneurysm neck to the aneurysm dome-was an independent predictor of aneurysm rupture. Aspect ratio, size ratio, parent vessel diameter, presence of daughter sac, and aneurysm angle were not independent predictors of rupture.

Conclusions:
After controlling for aneurysm size and location, the aneurysm perpendicular height remained a predictor of UIA rupture during long-term followup. The assessment of perpendicular height may be helpful in clinical practice, in addition to the other key predictors of UIA rupture, aneurysm maximum diameter and location. Further investigation into the use of perpendicular height as a predictor of rupture in patients with UIA is indicated.
Abstract TMP31: Peripheral Nerve Stimulation Paired with Constraint-Induced Therapy to Enhance Post-Stroke Upper Extremity Motor Performance
Authors: Carrico Cheryl , Chelette KC , Nichols Laurie , Sawaki Lumy
Published: July 2021

Research has shown that peripheral nerve stimulation (PNS) can enhance motor learning following cortical lesions. Studies have also shown that intensive upper extremity motor training can significantly enhance post-stroke motor performance. Constraint-induced therapy (CIT) is a form of intensive training that restricts use of the non-paretic upper extremity during repetitive, task-oriented motor training of the paretic extremity. Extensive evidence has validated the effectiveness of CIT for enhancing post-stroke upper extremity motor recovery. No studies have evaluated how PNS may modulate the effects of CIT. Therefore, we conducted a pilot study of PNS paired with CIT and hypothesized that in subjects with stroke, pairing CIT with active PNS would lead to significantly more improved motor function in the paretic upper extremity than CIT paired with sham PNS. Outcome measures included the Fugl-Meyer Assessment Scale (FMA; primary outcome measure), the Wolf Motor Function Test (WMFT), and the Action Research Arm Test (ARAT). Nineteen chronic stroke subjects with mild to moderate upper extremity motor deficit received 2 hours of either active (n=10) or sham (n=9) PNS preceding 4 hours of CIT for 10 consecutive weekdays. Changes in FMA, WMFT, and ARAT were analyzed using factorial ANOVA. Results showed significant (p<0.05) change in all measures at completion evaluation compared with baseline (FMA (p=0.005); WMFT (p=0.030); ARAT (p=0.020)) as well as 1-month follow-up compared with baseline (FMA (p=0.048); WMFT (p=0.045); ARAT (p=0.047)). These results highlight the enormous potential for PNS paired with CIT to enhance post-stroke upper extremity motor recovery more effectively than CIT alone.
Abstract TMP38: Diminished Cortical Thickness and Increased Oxygen Extraction Fraction in Moyamoya Disease
Authors: Lee John , Sagar James , Zipfel Gregory , Zazulia Allyson , Derdeyn Colin
Published: July 2021

PURPOSE:
Chronic hemodynamic impairment may lead to reduced cortical thickness, perhaps related to metabolic down-regulation in cortical neurons. The purpose of this study was to determine whether hemodynamic impairment correlated with diminished cortical thickness in patients with idiopathic moyamoya phenomenon.

METHODS:
The study was a retrospective analysis of a prospective, blindly-adjudicated, multicenter patient cohort. Inclusion criteria required moyamoya phenomenon diagnosed by catheter angiography and presumed idiopathic basal arterial occlusive disease. Oxygen extraction fraction (OEF) was measured using positron emission tomography (PET). Hemodynamic impairment was determined by comparing the OEF of middle cerebral artery territories to cerebellar regions and to normal control subjects. MR imaging was obtained concurrently with PET, within several hours, and cortical thickness estimates were made with Freesurfer (http://surfer.nmr.mgh.harvard.edu). OEF measurements were then compared to cortical thickness measurements.

RESULTS:
Adequate MR studies were available for 40 subjects. Mean age was 44 years. Eleven were male. Thirty-one had bilateral disease. Three had increased OEF in both hemispheres and four had unilateral increased OEF. Three patients underwent revascularization surgery during follow-up. Robust linear regression of relative cortical thickness to relative OEF is shown below: the slope was -0.02693 (-0.03002, -0.02384), the intercept was 1.022 (1.019, 1.025) at 95% confidence. Pearson’s R-square was 0.9648.

CONCLUSIONS:
Chronic hemodynamic impairment may be associated with reduced cortical thickness. This may reflect reversible down-regulation or irreversible subclinical ischemic injury. Supported by NINDS RO1 NS051631, 1 UL1 RR024992-01, 1 TL1 RR024995-01 and 1 KL2 RR 024994-01 from the National Center for Research Resources (NCRR).
Abstract TMP48: Stroke Symptoms and Risk of Future Hospitalization: Implications for an Easy and Quick Screening for an Important Patient-Centered Outcome
Authors: Howard Virginia J , Rhodes J. D , Judd Suzanne E , Kleindorfer Dawn O , Alexandrov Anne W , Allen Shauntice , Soliman Elsayed Z , Safford Monika M , Meschia James F , Howard George ,   for the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study
Published: July 2021

Background:
Stroke symptoms in the general population are common (≈18% of adults 45+) and are associated with future stroke. These symptoms may also identify a broad spectrum of clinically-undetected vascular conditions.

Methods:
Stroke symptoms (sudden weakness, numbness, unilateral or general loss of vision, and loss of ability to communicate or understand) and time to self-reported hospitalization for any cardiovascular (CVD) reason (heart, stroke, or TIA) or stroke were assessed in the REGARDS Study (a national, population-based, longitudinal study of 30,239 African-American and white adults > 45 years enrolled 2003-2007). The symptom-hospitalization association was assessed by proportional hazards analysis in persons stroke/TIA-free at baseline, with adjustment for demographics (age, race and sex), further adjustment for SES (income and education), CVD risk factors (smoking, hypertension, diabetes, dyslipidemia, atrial fibrillation and heart disease), and “perceived health status.”

Results:
Over an average follow-up of 5.6 years, presence of any stroke symptom was associated with greater risk of hospitalization for stroke (11% versus 6%; HR = 1.68; 95% CI: 1.52 - 1.85), a risk only modestly attenuated by adjustment for SES (HR = 1.59; 95% CI: 1.44 - 1.76), risk factors (HR = 1.44; 95% CI: 1.29 - 1.60), and perceived health (HR = 1.37; 95% CI: 1.23 - 1.53). However, presence of any stroke symptom was more strongly related to hospitalization for CVD (42% vs. 24%; HR = 1.92; 95 CI: 1.82 - 2.03), only modestly mediated by adjustment for SES (HR = 1.82; 95% CI: 1.73 - 1.93), risk factors (HR = 1.66; 95% CI: 1.57 - 1.76), and perceived health (HR = 1.57; 95% CI: 1.48 - 1.66).

Conclusions:
Stroke symptoms appear to be a marker not only for stroke risk, but also for general CVD. Simple questions can identify 18% of the general population that have over a 40% chance of hospitalization for CVD over a 5-year horizon. Implications for potential intervention to reduce risk are profound.
Abstract TMP49: Yield of Diagnostic Evaluation in Major Stroke Phenoytypes
Authors: Majersik Jennifer J , Arsava Ethem M , Brown Robert D , Grewal Raji , Jern Christina , Jiménez-Conde Jordi , Jood Katarina , Kittner Steven J , Labovitz Daniel L , Lindgren Arne , Meschia James F , Peddareddygari Leema R , Pera Joanna , Rhodes J. D , Rosand Jonathan , Rundek Tatjana , Slowik Agnieszka , Southerland Andrew M , Woo Daniel , Worrall Bradford B , Ay Hakan ,   for the NINDS Stroke Genetics Network (SiGN) investigators
Published: July 2021

Background:
Considerable disagreement exists among experts regarding the appropriate extent of diagnostic testing after ischemic stroke (IS). Evidence-based data guiding stroke evaluation for individual patients according to the underlying phenotype are unknown. We sought to determine the yield of cardiac and arterial evaluations for identifying an alternative major stroke etiology in patients with a given phenotype in the NINDS Stroke Genetics Network (SiGN).

Methods:
SiGN is a consortium of IS studies at 22 US and European sites aiming to identify stroke susceptibility genes. Adjudicators certified in Causative Classification of Stroke (CCS) system determined major etiologic stroke phenotypes based on chart review. All diagnostic data entered into the CCS software were stored in a confidential database. We determined the probability of identifying an alternative major abnormality based on cardiac (history, EKG, echocardiography) and arterial [intracranial (IC), extracranial (EC)] evaluations in 3 stroke phenotypes: lacunar infarct (LI), large artery atherosclerosis (LAA), and cardiac embolism (CE). Proportions of alternative major etiologies were calculated in patients with complete evaluations in each phenotype.

Results:
The analyses included 15720 patients. Among these, 2299 had phenotypic subtype of LI (1660 with cardiac and 1691 with arterial evaluations); 4228 had CE (2451 with arterial evaluation); and 2613 had LAA (2047 with cardiac evaluation). Cardiac evaluation revealed a major cardiac source of embolism in 12.3% of patients with LI and 20.3% with LAA. Echocardiography demonstrated an additional major structural cardiac source not seen by history/examination/EKG in 1.9% and 1.6% in LI and LAA respectively. Arterial evaluation led to the identification of ≥50%ipsilateral stenosis in 13.5% (IC: 8.9%, EC: 5.8%) of patients with LI and 17% (IC: 8.1%, EC: 11.3%) of those with CE. In LI patients with complete cardiac and vascular evaluations, 24.1% had an alternative major stroke etiology.

Conclusions:
A considerable proportion of IS patients with LI, LAA, and CE harbor an alternative major etiology. In the future, these results can be used to generate evidence-based and cost-effective evaluation and management strategies.