bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP23: Fetal Intraparenchymal Hemorrhage In Col4a1/2-related Disorders
Authors: Vassar Rachel , George Elizabeth , Gano Dawn , Glenn Orit
Published: February 2023

Introduction:
COL4A1/A2 mutations affecting the alpha 1 and 2 chains of type IV collagen are increasingly recognized as a potential cause of intracranial hemorrhage across the lifespan. We aim to describe fetal MRI findings and clinical outcomes in seven cases of fetal intraparenchymal hemorrhage (IPH) associated with COL4A1/A2 mutations.

Methods:
Subjects with COL4A1/A2 mutations were identified from a retrospective single-center cohort study of fetal IPH identified on fetal brain MRI between 1998-2021. Imaging findings were reviewed by two pediatric neuroradiologists, and clinical data were collected from electronic medical records.

Results:
Among the seven subjects with fetal IPH and COL4A1/A2 mutations, fetal MRI was performed at median gestational age (GA) 29 weeks (range 22-36 weeks) and demonstrated supratentorial IPH in 7/7 with variable size of hemorrhage, including 4/7 with multifocal hemorrhage
(Figure 1).
Four fetuses were liveborn at median GA 39 weeks (range 33-42 weeks); three pregnancies were terminated. Postnatal imaging revealed recurrent IPH in 1/4 cases, but no cases had recurrent IPH after the neonatal period. None of the seven cases had known family history of COL4A1/A2 or IPH; genetic testing revealed 5/7 with COL4A1 mutation, 1/7 with COL4A2 mutation, and 1/7 with 13q34 deletion with associated loss of COL4A1 and COL4A2 genes. Clinical follow-up data was available for the four liveborn cases through ≥12 months; three had mild hemiplegic cerebral palsy and one had severe spastic quadriplegia. None required CSF diversion, none had epilepsy, and one had visual impairment.

Conclusions:
Our series suggests that COL4A1/A2 mutations can present as fetal IPH with a wide range of phenotypes ranging from unifocal to multifocal IPH without additional systemic involvement, and that prenatal imaging severity may be associated with early clinical outcomes. COL4A1/A2 testing should be considered in all cases of prenatal IPH, regardless of severity.
Abstract TMP27: Association Of The Serum Inflammatory Markers With The Periventricular And Deep White Matter Hyperintensity
Authors: Hannawi Yousef , Vaidya Dhananjay , Yanek Lisa R , Kral Brian G , Becker Lewis C , Nyquist Paul A
Published: February 2023

Introduction:
Markers of systemic and vascular inflammation have been associated with cerebral small vessel disease (cSVD). However, their association with cSVD lesions within individual white matter regions remains unclear. We hypothesized that there are different associations of serum cytokines with the periventricular white matter hyperintensity (PVWMH) and deep WMH (DWMH).

Methods:
Apparently healthy participants aged ≥50 years with brain MRI in the Genetic Study of Atherosclerosis Risk were studied. Circulating inflammatory markers measured included: hs-CRP, IL-6, MCP1, ICAM, TNF-α, VCAM and IL-4. The relative association of these markers with PVWMH and DWMH within individuals were determined using multilevel linear models adjusted for age and cardiovascular risk factors.

Results:
A total of 435 subjects (age 58.9±6.1 years, 58.4% female, 39.5% black) with moderate WMH burden were studied (Total WMH: 1703[607-4626] mm
3
, PVWMH :871[152-2593] mm
3
, DWMH: 388[157-1023] mm
3
). Significant negative associations of total WMH volumes and hs-CRP (β=-0.2, P=0.04) as well as IL-6 (β=-0.15, p=0.04) were observed. The associations of total WMH with MCP-1, ICAM, VCAM, IL-4 and TNF-α were not significant. In the multilevel models, designed to compare difference between DWMH and PVWMH within individuals, there were significant differences in the relative association of PVWMH vs DWMH with hs-CRP and IL-6 (p=0.001 & p=0.04, respectively). DWMH was more strongly associated with hs-CRP and IL-6 (β=0.08, β=0.14, respectively) than PVWMH, which had negative association with these markers (β=-0.35, β=-0.05, respectively). There were no differences in the association of PVWMH vs DWMH and the other markers.

Conclusions:
DWMH is positively associated with increasing IL-6 and CRP when compared to PVWMH which is negatively associated with them. This suggests that systemic inflammation is more preferentially associated with DWMH lesions.
Abstract TMP37: Gene Expression May Predict Symptom Onset Time In Acute Ischemic Stroke
Authors: Larkins Christine , Hilker Nicholas C , Hairston Marla , Bozeman Andrea , Kracht Michael , Renati Swetha , Rose David Z , Beba Abadal Kanita , Sallam Maha , Burgin W S
Published: February 2023

Introduction:
Imprecise timing of symptom onset (SO) in patients with acute ischemic stroke (AIS) may impact eligibility for reperfusion therapy. Unreliable “last-known-well” (LKW) estimates may reduce the use of thrombolytic or endovascular treatments. A blood biomarker that serves as a “stroke clock” could minimize uncertainty and augment treatment rates.

Methods:
The single-center VuEssence Stroke Trial (VEST) evaluated gene expression biomarkers in adult ED patients with suspected AIS, a LKW time < 24hrs, and timing of SO accurate within a 0-3 hour time frame. At ED presentation and before reperfusion treatment, whole blood was collected in PAXgene RNA tubes for RNA-sequencing and gene expression analysis. Researchers blinded to molecular results adjudicated final diagnosis (AIS vs stroke mimic) and estimated time of SO based on times of witnessed onset (WO), LKW, and symptom discovery (SD). The confirmed AIS subgroup with WO timing, or ≤60 minutes between LKW and SD, was analyzed.

Results:
Of AIS patients, 56 met criteria (52% men, mean age 71.6). The average time from SO was 148 minutes (range 48-490). After RNA-sequencing, linear regression showed 684 genes with a significant linear time-related expression change in reference to time from SO (<0.2 Benjamini-Hochberg p-adjusted). A subgroup of 210 genes with <0.004 p-values and linear coefficients >0.25 were used to generate multiple classifiers of up to 12 genes that identified AIS <2.5 hrs from SO. Each gene is used in at least one classifier with other genes selected to maximize a measure of accuracy. The top panels showed both high sensitivity and specificity (
table
).

Conclusion:
Using a biological “stroke clock” biomarker instead of SO timing may streamline evaluations of suspected AIS, augment reperfusion therapy rates, and improve outcomes. VEST identified time-related gene expression changes that may accurately classify AIS <2.5 hrs from SO. These gene panels will require further validation.
Abstract TMP44: Artificial Intelligence-driven Automated Intracerebral Hemorrhage Volume Calculation Is More Accurate Than ABC/2
Authors: Odland Ian C , Schuldt Braxton R , Liu Kayla , Wu Dylan S , Downes Margaret H , Vasan Vikram , Rossitto Christina P , Hardigan Trevor , Kellner Christopher P
Published: February 2023

Introduction:
Treatment of spontaneous intracerebral hemorrhage (ICH) requires rapid, accurate estimation of hemorrhage volume to determine appropriate patient care and guide prognosis. ICH volume estimation on Computed Tomography (CT) imaging using the ABC/2 formula is the clinical gold standard, however this method can be inaccurate, suffers from observer scoring variability, and takes time to make the measurement on a workstation. Semi-Autonomous Segmentation (SAS) is the gold standard for hemorrhage volume estimation, however it is not used clinically due to the increased time for analysis. Recently, artificial intelligence (AI) driven segmentation has been developed (Viz.ai, San Francisco, California) to automatically detect ICH and calculate hematoma volume.

Objective:
Our goal is to validate the accuracy of the Viz.ai ICH segmentation algorithm as a tool for determining hemorrhage volume by comparing its performance to both ABC/2 and SAS.

Methods:
Seventy head CTs positive for ICH were analyzed with SAS in 3D Slicer to determine ICH volume as the standard reference volume. The same CT scans were then analyzed using the ABC/2 method. Finally, scans were uploaded to Viz.ai for ICH volume analysis.

Results:
Compared against standard SAS, Viz.ai ICH volumes were more accurate than ABC/2 in 77% of cases. Average difference between Viz.ai ICH volume and SAS ICH volume was 4.9±4.2 mL (R2=0.98). Average difference between ABC/2 ICH volume and SAS ICH volume was 10.6±11.4 mL (R2=0.77).

Conclusion:
This study indicates that Viz.ai more accurately estimates ICH volume than ABC/2 over a broad range of hematoma volumes when compared to standard SAS, which when coupled with significantly faster analysis compared to SAS justifies the use of AI in ICH triage workflow.
Abstract TMP46: Large Vessel Occlusion Stroke Knowledge And Clinical Training In Emergency Medical Service Personnel In The United States
Authors: Asif Kaiz S , Novakovic Robin , Ortega-Gutierrez Santiago , Nguyen Thanh , Jagolino-Cole Amanda L , Jumaa Mouhammad A , Al-Bayati Alhamza R , Liebeskind David S , Nour May , Castonguay Alicia , Desai Shashvat , Yavagal Dileep , Mokin Maxim , Sheth Sunil , Teleb Mohamed S , Kumar Prateek , Hartman Joshua , Miller Nicholas , Jhadav Ashutosh , Hassan Ameer E , Mehta Brijesh
Published: February 2023

Background:
Stroke education of emergency medical service (EMS) personnel improves stroke recognition, prenotification, and thrombolytic delivery. Prehospital identification of large vessel occlusion (LVO) stroke may facilitate the creation of a regional bypass protocol and improvement of intrahospital and interhospital workflows. However, the current status of EMS personnel’s knowledge of LVO, their stroke severity assessment training, and preferences in educational methods have not been studied. We conducted an EMS survey across the United States.

Methods:
The Society of Vascular and Interventional Neurology (SVIN) in collaboration with EMS-World created an online questionnaire distributed to all subscribers of EMS-World involved in pre-hospital work. It included 12 multiple-choice questions to test participants on LVO knowledge, stroke center certification levels, prior LVO education, and preferences on educational content delivery.

Results:
The survey email was opened by 1830 subscribers out of whom 1107 (60%) completed the survey across 50 states in the United States. Respondents identified themselves as paramedics/EMTs (91.4%), ground critical care (5.7%) and flight crew (2.9%). The number of stroke patients that survey participants transported in the past year was <10 for 618 (55.8%), 10 to 25 for 332 (30%), and >25 (14.2%). Two hundred eighty-five (25.8%) participants answered both LVO knowledge questions correctly and 379 (34.2%) answered one correctly. Only 128 (11.6%) correctly identified all types of centers with thrombectomy capability. Although 877 (79.2%) were familiar with at least one stroke severity scale, 376 (34%) denied receiving training to perform them. Five sixty-seven (51.2%) respondents preferred in-person training for LVO training and 429 (38.8%) an online training program. About half of all respondents (535,48%) picked 'lack of standardized LVO training' as the greatest hurdle to pre-hospital LVO management.

Conclusion:
EMS providers in the United States reported inadequate LVO training and demonstrated gaps in knowledge of LVO, stroke severity scales, and stroke center levels. Systematic efforts to enhance and standardize the educational content and delivery of LVO education are urgently needed.
Abstract TMP60: Misdiagnosis Of Posterior Reversible Encephalopathy Syndrome And Reversible Cerebral Vasoconstriction Syndrome In The Emergency Department
Authors: Liberman Ava L , Zhang Cenai , Parikh Neal S , Salehi Omran Setrah , Navi Babak , Merkler Alexander E , Kamel Hooman
Published: February 2023

Introduction:
Syndromes of cerebrovascular dysregulation such as posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) can be challenging to diagnose given their rarity and the need for advanced neuroimaging to diagnose them. We sought to measure the rate of potential PRES/RCVS misdiagnosis in the ED and identify features associated with misdiagnosis.

Methods:
We conducted a retrospective cohort study of patients with PRES/RCVS using deidentified administrative claims data from all nonfederal EDs and hospitals across 11 states from 2016-2018. To identify patients with PRES/RCVS, we used the previously validated
ICD-10-CM
codes I67.841 and I67.83. We defined patients with a probable misdiagnosis of PRES/RCVS as those with an ED visit resulting in discharge to home that occurred within the 14 days prior to their PRES/RCVS hospitalization. Only preceding ED visits where a non-specific neurological condition (e.g., headache, dizziness, numbness) was diagnosed were considered instances of probable ED misdiagnosis. Standard tests of comparison between patients with versus without probable misdiagnosis were used to identify patient-level and ED facility-level features associated with misdiagnosis.

Results:
We identified 4,633 patients hospitalized for PRES/RCVS; the majority (4,169; 90.0%) had PRES. A total of 210 patients (4.5%, 95% CI: 3.95-5.17) had at least one preceding ED visit with a probable misdiagnosis; these patients were younger (mean age 47.7 vs. 53.8 years; P<0.001) and more often female (80.4% vs. 69.7%: P<0.001). Misdiagnosed patients generally had fewer vascular risk factors including hypertension (46.3% vs. 84.9%; P<0.001) and more often had a history of headache (81.1% vs. 22.6%; P<0.001) and psychiatric disease (48.6% vs. 34.9%; P<0.001) as compared to patients without an ED misdiagnosis. Facility factors inversely associated with probable misdiagnosis included an ACGME-approved residency (63.4% vs. 75.3%; P<0.001) and on-site neurological services (74.9% vs. 84.7%; P<0.001).

Conclusion:
Probable ED misdiagnosis occurred in nearly 1 of 20 cases of PRES/RCVS in a large, multistate cohort.
Abstract TMP68: Core/perfusion Mismatch In Acute Ischemic Stroke With M2 Occlusion: Prevalence And Associated Factors.
Authors: Seners Pierre , Yuen Nicole , Heit Jeremy J , Escribano Paredes Jose Bernardo , Carrera Emmanuel , Snyder Sarah , Mlynash Michael , Christensen Soren , Obadia Michael , Savatovsky Julien , Lansberg Maarten G , Albers Gregory W
Published: February 2023

Background:
The benefit of mechanical thrombectomy (MT) in acute ischemic stroke (AIS) patients with M2 occlusion is uncertain. Observational studies suggest that perfusion imaging may help select optimal M2 candidates for MT. We aimed to study the prevalence and factors associated with core/perfusion mismatch, as assessed by both CT and MRI, in an unselected population of AIS with M2 occlusion.

Methods:
Retrospective observational study including AIS patients with M2 occlusion and baseline perfusion imaging (MRI or CT) performed within 24hrs from last seen well. To avoid selection bias, patients were selected from the prospective registries of 3 centers with systematic use of perfusion imaging, including both MT-treated and untreated patients. Core/perfusion mismatch was defined as mismatch ratio (Tmax>6s/ core volume) >1.8 and mismatch volume (Tmax>6s - core volume) >15mL.

Results:
Overall, 156 and 196 patients were included in the MRI and CT cohorts, respectively. Last-seen-well to imaging time was 5.6hrs (IQR 3.9-9.7) and 3.5hrs (1.5-9.8) in the MRI and CT cohorts, and 103/156 (66%) and 134/196 (68%) had proximal M2 occlusions (the remainder had distal M2 occlusions). Median ASPECT score was 7 (5-8) and 8 (7-9), and core/perfusion mismatch was present in 70/156 (45%) and 167/196 (85%) patients. In both cohorts, mismatch was less frequent in distal M2 occlusions and among patients with lower ASPECTS (Figure). Multivariable analysis showed higher ASPECT scores (OR=3.09, 95%CI=2.11-4.52,
P
<0.001 and OR=2.41, 95%CI 1.63-3.58,
P
<0.001 in the MRI and CT cohorts) and proximal M2 occlusion (with distal M2 as a reference: OR=3.94, 95%CI=1.68-9.26,
P
=0.002 and OR=32.78, 95%CI 8.36-128.47,
P
<0.001 in the MRI and CT cohorts) were independently associated with core/perfusion mismatch.

Conclusion:
Perfusion imaging may be useful in triaging M2 patients, particularly for those with ASPECT score <8 and distal M2 occlusions. This has implication for trials.
Abstract TMP7: Efficacy And Safety Of Intravenous Tirofiban Combined With Endovascular Therapy For The Treatment Of Basilar Artery Occlusion Due To Large-artery Atherosclerotic
Authors: Liu Shuai , Zi Wenjie
Published: February 2023

Background:
This study aimed to evaluate whether intravenous tirofiban can improve the functional outcome without promoting risk of intracerebral hemorrhage (ICH) in patients with basilar artery occlusion (BAO) due to large-artery atherosclerotic (LAA) receiving endovascular therapy (EVT).

Methods:
Consecutive patients with acute BAO duet to LAA within 24 h who underwent EVT and had tirofiban treatment from the BASILAR Registry study were enrolled. All eligible patients were dichotomized into tirofiban and non-tirofiban subgroups according the use of intravenous tirofiban. The primary efficacy outcome was the favorable functional outcome (defined as mRS score of 3 or less), Safety outcomes were mortality within 90 days and intracranial hemorrhage (ICH) within 48 hours.

Results:
A total of 417 patients were included in this study, of which 275 were in the tirofiban group and 142 were in the non-tirofiban group. After adjusting for multiple factors, patient in the tirofiban group were 1.17 (95% confidence interval [CI], 1.05-1.31) times more likely to achieve favorable outcome at 90 days than those in the non-tirofiban group. The mortality of the tirofiban group was higher than that of the non-tirofiban group (40.7% vs. 58.5%; adjusted risk ratio, 0.61; 95% CI, 0.74-0.89;
P
<0.001). The 1-year follow-up results were also similar to that at 90 days. Any ICH occurred in 19 (7.1%) patients in the tirofiban group, which was lower than that of 22 (15.8%) in the non-tirofiban group (adjusted risk ratio, 0.45; 95% CI, 0.26-0.68; P=0.004) and symptomatic ICH occurred in 15 (5.2%) patients in the tirofiban group, which was lower than that of 17 (12.2%) in the non-tirofiban group (adjusted risk ratio, 0.40; 95% CI, 0.21-0.76; P=0.005).

Conclusions:
Tirofiban may associated with improve 90-day favorable outcomes and reduced mortality risk decreased incidence of ICH in patients with BAO due to LAA receiving EVT. The treatment effect of tirofiban may be maintained for one year.
Abstract TMP70: Relevance Of Persistent Perfusion Deficits On Clinical Outcome After Sucessful Endovascular Treatment
Authors: Valls Adrian , Puig Josep , Palomar Alicia , Laredo Carlos , Werner Mariano , Remollo Friedemann Sebastià , Dorado Laura , Serena Joaquin , Munuera Josep , Perez de la Ossa Natalia , Gomis Meritxell , Bustamante Alejandro , Carbonell Jaime , Larrañaga Clara , Castaño Carlos , Muñoz Lucía , Palomeras Ernest , Domenech Sira , Terceño Mikel , Davalos Antoni , Millan Monica , Hernandez-Perez Maria
Published: February 2023

Introduction:
After achieving successful reperfusion some acute stroke patients still exhibit persistent perfusion deficits. These deficits have been defined in a heterogeneous manner by using CBF, CBV or Tmax maps as a perfusion deficit in the previous ischemic penumbra (impaired microcirculation perfusion-IMP) or inside the infarcted tissue (no reflow-NR). The significance, frequency and pathophysiology of this phenomenon are so far unknown.

Methods:
Prospective cohort of patients with isolated anterior intracranial occlusion undergoing endovascular treatment (EVT) and achieving complete recanalization (final mTICI≥2B). Brain MRI was performed on arrival (pre-EVT) and <2h after EVT (post-EVT). Infarcted tissue was segmented on DWI pre-EVT. Pre and post-EVT perfusion maps were obtained with Olea software. NR was defined in the post-EVT perfusion maps as the region inside the infarcted tissue which showed a CBV<15% compared to the contralateral side, while IMP was the equivalent area inside the previous tissue in penumbra. We evaluated the association between both NR and IMP and NIHSS at 24h, NIHSS at discharge and modified Rankin score (mRS) at three months adjusting by baseline NIHSS and final mTICI.

Results:
Thirty-five patients were included. All of them had IMP areas and 25 (71%) had NR areas. The median volume of NR and IMP was 3.43ml [IQR 1.43-8.81], corresponding to 17.9% of the infarcted tissue [IQR 4.2-50.3] and 33.9ml [IQR 14.0-69.3] (27.7% [IQR 8.2-51.2] of the penumbra) respectively. Patients with NR areas had higher NIHSS at 24 h and at discharge and higher mRS at 3 months. Volume of NR was independently associated with higher NIHSS at 24 h and at discharge. No independent association was found with IMP volume. Neither NR nor IMP were associated with hemorrhagic transformation. Patients receiving rTPA previous to EVT showed higher perfusion values inside the infarct than patients with primary EVT (2.31 mL/100g [1.48-2.43] vs 0.92 [0.7-1.47] p=0.02), although NR areas appeared in the same proportion in both groups.

Conclusions:
No reflow phenomenon can be a marker of poor outcome in the early evaluation of successfully recanalized stroke patients especially when the persistent perfusion deficit is located inside the infarcted tissue.
Abstract TMP72: Multimodal Prediction Of Stroke Severity
Authors: Bonkhoff Anna K , Cohen Alexander , Drew William , Ferguson Michael A , Lin Christopher , Schaper Frederic , Bourached Anthony , Bretzner Martin , Hong Sungmin , Regenhardt Robert W , Schirmer Markus D , Wu Ona , Jern Christina , Lindgren Arne G , Maguire Jane , Fox Michael , Rost Natalia S
Published: February 2023

Introduction:
Predicting individual outcomes post-stroke with the highest possible accuracy is a crucial steppingstone in the realization of precision medicine. We here evaluated various types of lesion information in their capacity to predict stroke severity in a large cohort of patients with acute ischemic stroke.

Methods:
A total of 1,075 patients of the MRI-GENIE study [age: 64.2(14.7), 38% women] contributed to analyses (N=792 as train and N=283 as test sample). We employed ridge regression with hyperparameter optimization and nested five-fold cross-validation to predict acute NIHSS-based stroke severity. Our baseline model considered DWI lesion volume. Further models tested structural lesion location, indirect structural and functional lesion connectivity, individually and combined with lesion volume. Data was preprocessed by principal component analysis (PCA), retaining 95% of the variance of the original data. Model performance was compared in terms of explained variance (R-squared) and 95% confidence intervals in the outer loop of the training set and the test set.

Results:
Structural lesion connectivity enabled the highest prediction performance in the test set (
Figure 1
). Prediction performance did not change notably with inclusion of lesion volume information. This contrasted with the combination of functional lesion connectivity and lesion volume that achieved a substantially higher prediction performance compared to functional lesion connectivity or lesion volume in isolation. Lesion location resulted in a prediction performance that was in the range of lesion volume alone and significantly lower than the ones of structural or functional connectivity with lesion volume.

Conclusions:
Structural connectivity facilitated the most convincing prediction of stroke severity. The capacity of functional lesion connectivity was substantially improved by the inclusion of lesion volume, indicating both represent complementary information.
Abstract TMP77: Iga+ B Cells Are Recruited To The Brain After Intracerebral Hemorrhage
Authors: Ohashi Sarah N , O'Connor Kevin C , Sansing Lauren H
Published: February 2023

Introduction:
There is ample evidence of a B cell response in human stroke patients, and evidence that long-term cognitive decline is linked to ongoing B cell activation in ischemic stroke models in mice. However, the role of B cells in hemorrhagic stroke, particularly at late timepoints, is unknown.

Methods:
Intracerebral hemorrhage (ICH) was induced in 12-week male C57BL/6 mice by collagenase (or saline for sham controls) injection into the striatum. Mice were perfused 2, 4, or 8 weeks post-ICH or sham, ipsilateral and contralateral hemispheres were harvested and B cell counts analyzed by flow cytometry. Motor deficits were measured via grid walk test and short-term memory was tested by Y maze at 1, 2, 4, 8, 12, and 16 weeks post-ICH or sham. B cell repertoire analysis was conducted by PCR amplification and molecular cloning of B cells in 8 week post-ICH or naïve brain tissue, followed by Sanger sequencing and comparison to the IMGT database.

Results:
B cells are robustly recruited to the ipsilateral hemisphere as early as 2 weeks post-ICH (2439 +/- 987 cells; n=5) and persist at 8 weeks (14,162 +/- 12,103 cells, n=4). At 2 and 4 weeks a small fraction of B cells in the ipsilateral hemisphere are IgA+ (2 weeks=14.0% +/- 6.8%, n=5; 4 weeks=13.3% +/- 4.6%, n=3). Interestingly, by 8 weeks post-ICH this proportion significantly increased in ICH (41.3% +/- 22.8, n=6) but not sham controls (12.0% +/- 11.8%, n=5). While our work has demonstrated no significant motor deficit after 2 weeks post-ICH, preliminary data suggests a cognitive short-term memory deficit starting 16 weeks post-ICH. Furthermore, we have found that post-ICH brain-infiltrating IgA+ B cells are somatically hypermutated and show diverse V gene usage.

Conclusion:
Our findings suggest that ICH induces a robust, delayed IgA+ B cell response within the affected brain hemisphere, underscoring the need to better understand how B cells shape post-stroke inflammation and recovery, particularly at late timepoints.
Abstract TMP78: Using Interventional CT Perfusion Imaging To Evaluate Cerebral Blood Volume Surrounding Intracerebral Hemorrhage Site Following Minimally Invasive Evacuation
Authors: Smith Colton J , Rossitto Christina P , Manhart Michael , Fuhrmann Imke , Dinitto Julie , Mocco J D , Kellner Christopher P
Published: February 2023

Introduction:
Computed tomography perfusion (CTP) characterizes hemodynamic changes within brain tissue, particularly after stroke. This study aims to quantify cerebral blood volume (CBV) changes and identify predictors of CBV increase in the pericavity parenchyma after minimally invasive intracerebral hemorrhage evacuation (MIS for ICH).

Methods:
Thirty-two patients underwent MIS for ICH with pre/postoperative native CT imaging and intraoperative perfusion imaging (DynaCT PBV Neuro, Artis Q, Siemens). Scans were segmented using ITK-SNAP software to calculate hematoma volumes pre/post-evacuation and to delineate the pericavity tissue. Helical CT segmentations were registered to cone beam CT data using elastix software. Mean CBVs were computed inside subvolumes by dilating the segmentations with spheres with varying diameters.

Results:
In 27 patients with complete imaging, CTP analysis demonstrated significant increases in CBV from the 6 mm to 20 mm pericavity regions. CBV increased on average 32.7% from 2.27 mL/100mg (IQR 1.87-3.02) to 2.80 mL/100mg (2.41-3.61) in the 10 mm pericavity region (P=0.003). Factors associated with increased CBV in the univariate analysis (P≤0.10) included age (P=0.082) and percentage of hematoma evacuation (P=0.078). Upon multivariate linear regression, age (OR 4.49, [95% CI, 1.01-1.98], P=0.048) and percentage of hematoma evacuation (OR 4.09, [95% CI, 1.70-9.84], P=0.046) remained significantly predictive of increased CBV.

Conclusions:
CTP analysis demonstrated a significant increase in pericavity cerebral blood volume after MIS for ICH. Patient age and hematoma evacuation percentage may be predictive of CBV increase after MIS for ICH.
Figure 1:
Topographic map showing blood flow improvement at different distances from the lesion.
Abstract TMP86: Clinical Outcomes Of Endovascular Thrombectomy Versus Acute Medical Treatment In Acute Ischemic Strokes Secondary To Medium Vessel Occlusion
Authors: Fourcand Farah , Scarpiello Sean , Amireh Abdallah , Snyder Thomas , Vyas Shrinjay , Joshi Rudra , Dubinsky Ilya , Percival Brigitte , Zacharatos Haralabos , Mehta Siddhart , Kirmani Jawad F
Published: February 2023

Introduction:
Acute ischemic stroke (AIS) from arterial occlusions are treated with emergent endovascular thrombectomy (EVT) when clinically appropriate. Clinical outcomes of EVT in medium vessel occlusion (MVO) compared to large vessel occlusion (LVO) have neither been well established nor compared to alternate medical management. Our aim was to evaluate outcomes of patients with AIS secondary to MVO undergoing EVT.

Methods:
We conducted a retrospective chart review of patients presenting to with MVO-associated AIS undergoing EVT or aggressive intra-arterial thrombolytic treatment with concurrent administration of IV eptifibatide. We assessed occlusion site, NIHSS (presentation, 7 day or discharge, 3 months), mRS (baseline, 90-day), and intracranial hemorrhage (ICH) rate. MVO was defined as occlusion of pure M2 middle cerebral artery without M1 segment involvement, anterior cerebral artery A1 segment or more distal, and posterior cerebral artery P1 segment or more distal. Mann-Whitney U test, Fisher exact test statistic, and T-test statistic were used for analysis.

Results:
From August 2020 to December 2021, out of 175 patients who underwent EVT, 50 had MVO (n=33 M2 occlusion, n=12 M3 occlusion, n=1 for P1, P2, A1, A2, A3 each). Twelve subjects with MVO received aggressive medical management with concurrent IV eptifibatide. Subjects between arms were similar at baseline (median NIHSS 11 [95% CI 10.75, 14.32]; mean age 71.5 [95% CI 69.24, 73.77]; male 48.39% [n=30]). The difference between initial NIHSS and discharge NIHSS was statistically significant in the EVT arm (Z-Score=4.03; p-value < .00001) but not in the medical arm (Z-score=1.96; p-value 0.05). Hemorrhagic transformation occurred in 28% (n=14) of EVT arm and 16.67% (n=2) of medical arm. This was not statistically significant (Fisher value: 0.71). Median 90 day mRS was 1 (95% CI [0.89, 2.11]). The difference between 90 day mRS was not significantly different (Z-score=-1.20; p-value 0.23).

Conclusion:
In our patient cohort, endovascular therapy was safe in medium vessel occlusion and may have more favorable clinical outcomes as illustrated by higher delta NIHSS in the endovascular thrombectomy group. Larger, prospective studies are needed to validate our results.
Abstract TMP87: A Novel Approach For Automated First Pass Effect Prediction On Computed Tomographic Angiography In Acute Ischemic Stroke Patients
Authors: Zhang Jianhai , Bala Fouzi , Cimflova Petra , Singh Nishita , Benali Faysal , Hill Michael D , Qiu Wu , Menon Bijoy K
Published: February 2023

Background and Purpose:
First pass effect (FPE), or effective reperfusion with a single pass of endovascular thrombectomy (EVT) for acute ischemic stroke (AIS), is strongly associated with good functional outcome (mRS≤2) and can aid in optimal device selection for EVT. We aim to investigate the arterial tortuosity from great vessel origin to the intracranial occlusion location and predict first pass effect, automatically by a novel neural network, on computed tomographic angiography (CTA).

Materials and Methods:
Patients with thin-slice (≤2.5 mm) neck CTA from the ESCAPE-NA1 trial (Efficacy and safety of nerinetide for the treatment of AIS) were included. Arterial centerlines from the aortic arch to the intracranial occlusion site were manually traced by three experienced readers on CTA. The centerlines were modeled and organized by tortuosity. A model based on graph neural network (GNN) was proposed to predict FPE on the processed data. Model performance was compared to manual annotations and traditional classification algorithms using diagnostic statistics.

Results:
539 patients were included, with a 429/110 training/testing-ratio. FPE was observed in 136(31.7%, training set) and 35 (31.8%, testing set). The suggested model showed an overall good performance with an area under the receiver operating characteristic curve (AUC-ROC) of 0.66 (95% CI=0.65-0.67), precision of 0.46(17/37), sensitivity of 0.71(17/35), specificity of 0.61(55/75) and accuracy of 0.65(72/110), whereas the manually annotated features with traditional classification methods had an AUC-ROC of 0.54 (95%CI=0.53, 0.55), precision of 0.42(8/19), sensitivity of 0.23(8/35), specificity of 0.85(64/75) and accuracy of 0.65(72/110).

Conclusion:
An automated model for FPE prediction on CTA had better performance and higher sensitivity as compared to manual annotations and traditional machine learning algorithms, suggesting that it could be used in routine clinical practice prior to EVT.
Abstract TMP89: Examining The Impact Of Area Deprivation On Patient Outcomes In LVO AIS
Authors: Abdelkhaleq Rania , Dongarwar Deepa , Salazar-Marioni Sergio , Niktabe Arash , Tariq Muhammad B , Sheth Sunil A
Published: February 2023

Intro & Background:
The Area Deprivation Index (ADI) is a validated neighborhood-level measure that utilizes variables such as income, education, and employment to quantify relative socioeconomic disadvantages. Here we explore the impact of disparities on EVT access.

Methods & Materials:
From our prospectively maintained multi-hospital registry, we identified patients with LVO AIS from January 2019- June 2020. Patient addresses and zip-codes were validated using US Postal Service codes and matched to census-tract level ADI scores that were obtained from Neighborhood Atlas. ADI were categorized into high and low using the median ADI as the cutoff. The primary outcome was utilization of EVT and IV tPA and was determined using multivariable logistic regression and expressed as OR [95% CI]. All p-values are two-sided with p<0.05 defined as statistically significant. All analyses were conducted using RStudio (Version 1·2·5001).

Results:
Among 637 patients with LVO AIS, median age was 68, 46% were female, 53% were white, 27% were black, and 78% identified as Hispanic. Median state ADI was 5 IQR [5]. NIHSS was similar between low/high ADI (mean(SD): 13.3(7.75) vs 13.6(8.62), p-value 0.69) regions. ADI was significantly associated with race (6.41 vs 4, black vs. white, p-value 0.03). In the univariable analysis, patients treated with EVT had lower mean ADIs (5.2 vs. 4.6, no EVT vs. EVT, p<0.02). In multivariable analysis adjusted for age, sex, race, ethnicity and NIHSS, higher ADI was significantly associated with greater rates of IV tPA usage (OR 1.7 [1.01-2.98]) but not EVT usage (OR 0.63 [0.04-1.0])

Conclusion:
Patients residing in disadvantaged neighborhoods may have reduced rates of reperfusion therapy, despite comparable acute stroke presentation symptoms. These findings are consistent with prior studies demonstrating poorer health outcomes in these populations.
Abstract TMP93: Middle Meningeal Artery Embolization - A Preliminary Analysis Of Efficacy In Acute Settings And Among Patients With Major Co-morbidities
Authors: Morales Jose M , Qadri Sohaib , Molaie Amir , Beaman Charles , Kimball David , Kaneko Naoki , Tateshima Satoshi , Nour May , Szeder Viktor , Jahan Reza , Liebeskind David S , Duckwiler Gary , Saver Jeffrey L
Published: February 2023

Introduction:
Middle meningeal artery (MMA) embolization is an therapy utilized in the management of subdural hematomas (SDH). Based on promising preliminary data, several clinical trials are underway to evaluate the efficacy of this endovascular approach in patients with chronic subdural hematomas. However, consensus for the efficacy of MMA embolization has not been well established in acute settings or among patients with major co-morbidities.

Methods:
Patient data were gathered from consecutive cases performed at UCLA between 05/02/2018 and 08/26/2022. Retrospective chart review was performed to determine inpatient/outpatient status, mortality, co-morbidities, and time-to-death. Primary statistical analyses were performed to determine the proportion of patients.

Results:
Among the 111 patients meeting study entry criteria, 44 (39.6%) had acute, inpatient MMA procedures performed and 66 (40.4%) had elective procedures in the setting of advanced or terminal diseases (e.g. malignancy, cirrhosis). After follow-up of median 31.9 months, mean 17.4 months years, 86 (77.5%) of patients were still living and 25 (22.5%) were deceased. The age for both deceased and living patients was the same, 71±13 vs 71±16.1 years old. Mortality during follow-up was more common among patients undergoing MMA as an inpatient (47.8% vs 6.1%). Among the 25 deceased patients, mortality occurred within 1 year in 64% and beyond 1 year in 36%. Co-morbidity frequencies among deceased compared with surviving patients were: 40% vs 22%; solid tumor cancer in 28% vs 14%; cirrhosis in 32% vs 6%; and hematologic malignancy in 4% vs 4%. Among those deceased, 14 of 25 (56%) were diagnosed with a major co-morbidity (hematologic condition, cancer, or liver cirrhosis) at the time of the procedure. Among those living, 19 of 86 (22.1%) were diagnosed with a major co-morbidity (hematologic condition, cancer, or liver cirrhosis) at the time of the procedure.

Conclusion:
Patients with SDH undergoing MMA embolization on an acute inpatient basis have a high, nearly 50%, rate of mortality within the next 0.5-2 years, while patients electively treated despite major co-morbidities have a substantially higher survival rate.
Abstract TMP96: Area Deprivation Index (ADI) And NIHSS Predicts The Infarct Growth Rate (IGR)
Authors: Sari Murat , Dwairi Vanessa , Thoma Floyd W , Magnani Jared W , Rocha Marcelo
Published: February 2023

Introduction:
Socioeconomic status has been shown to affect the clinical outcome of cardiovascular disease and stroke. Early clinical severity and infarct growth rate (IGR) are highly variable across patients with anterior circulation large vessel occlusion (ACLVO) stroke but remain poorly understood. We aimed to measure the social determinants of early NIHSS and IGR in ACLVO stroke using the Area Deprivation Index (ADI), which incorporates housing, education, income, and employment status at the neighborhood level.

Methods:
Single-center retrospective study of all patients with acute intracranial ICA or proximal MCA occlusion and baseline CTP or MRI within 24 hours of stroke onset from 2014-2017. IGR (ischemic core volume / stroke onset to core imaging time, ml / hours) was calculated. Demographics, co-morbidities, admission NIHSS, ADI, and median income data were collected. Multivariable linear regression models tested the independent association between ADI and NIHSS (model 1) or IGR (model 2, including NIHSS).

Results:
A total of 165 patients were included in the analysis, with mean age 71 (SD, 15), 40 % male sex and median NIHSS 17(IQR, 12--21). In model 1, ADI (coefficient 0.07, 95% CI 0.025-0.13, P=0.004) and age (coefficient 0.11, 95% CI 0.4—0.19, P=0.003) were the only independent predictors of NIHSS. In model 2, ADI (coefficient 0.11, 95% CI 0.004-0.21, P=0.04) and NIHSS (coefficient 0.46, 95% CI 0.16-0.76, P=0.003) were the only independent predictors of IGR. Median income, sex, diabetes or hypertension status were not independently associated with NIHSS or IGR in these models.

Conclusions:
ADI is independently associated with worse stroke severity and faster infarct progression of ACLVO stroke. These findings have possibly important implications for public health care planning of stroke systems of care and enrollment in clinical trials of reperfusion therapies.
Abstract TP1: Impact Of Patient Characteristics And Covid-19 On Last Known Well To Arrival
Authors: Singh Tarvinder , Stuchiner Tamela L , Corless Leslie , Lesko Alexandra C , Lamorena Cecille , Bravo Christian Y , Polonchak Jillian , Baraban Elizabeth
Published: February 2023

Introduction:
Stroke is a medical emergency requiring prompt evaluation and treatment. COVID-19 disproportionally burdened certain socioeconomic groups and its impact on patient's hospital arrival and access to emergency services to treat stroke is unknown. This study examines whether there was an impact of patient characteristics and COVID-19 on last known well (LKW) to arrival.

Methods:
Data from our health system stroke registry comprised of 40 hospitals were used for the analysis. Patients with a diagnosis of Ischemic stroke (ISC) or Intracerebral Hemorrhage (ICH) discharged between Jan 1 2018 - Mar 15 2020 (pre-COVID) and Mar 16 2020 - Apr 10 2022 (pandemic period) were included in the analysis. Inpatient strokes were excluded. Multinomial logistic regression was used to determine the likelihood of presenting to the hospital in the hyperacute phase (<4.5 hours) and the acute phase (4.5 to 24 hours) compared to delayed phase (> 24 hours), adjusting for COVID-19 time period, race/ethnicity, mode of arrival, insurance type, stroke type, age, NIHSS at admit, and medical history.

Results:
A total of 25,102 patients were included in the analysis, of which 55.7% arrived in hyperacute phase, 37.7% acute phase, and 6.6% delayed phase. ICH patients (AOR 1.10, 95% CI 1.03, 1.18) were more likely than ISC patients to arrive in the hyperacute phase than delayed phase. Asian patients were less likely than white patients to arrive in the hyperacute phase (AOR 0.72, 95% CI 0.58, 0.88) than delayed phase. Patients with a history of dementia (AOR 1.69, 95% CI 1.05, 2.72), depression (AOR 1.19, 95% CI 1.02, 1.39), and afib/flutter (AOR 1.31, 95% CI 1.12, 1.53) were more likely to arrive in the hyperacute phase than delayed phase. Patients with history of diabetes (AOR 0.69, 95% CI 0.61, 0.77), smoking (AOR 0.71, 95% CI 0.60, 0.83) and drug/alcohol abuse (AOR 0.62, 95% CI 0.52, 0.75) were less likely to arrive in the hyperacute phase than delayed phase. COVID-19 time period, history of stroke, and insurance had no impact on time to arrival.

Conclusions:
While several patient characteristics and medical comorbidities were significantly associated with delay in arrival of stroke patients, the first two years into COVID-19 was not associated with delay in presentation.
Abstract TP100: Transfer Learning Based Cerebral Microbleed Detection As An Mri Biomarker For Cerebral Amyloid Angiopathy Spectrum Diseases
Authors: Gaj Sibaji , Man Shumei , Rothenberg Kasia , Jones Stephen , Shah Chintan , Uchino Ken , Nakamura Kunio
Published: February 2023

Objectives:
Quantifying cerebral microbleeds (CMBs) in cerebral amyloid angiopathy (CAA) is important, however manual counting of CMBs on brain MRI is laborious. This work aims to develop a novel automatic deep learning segmentation algorithm for fast and accurate quantification of CMBs on brain MRIs.

Method:
We used (a) internal dataset (susceptibility-weighted imaging [SWI] clinical scans from 83 patients with CAA) with heterogeneous protocols on 1.5T and 3T scanners and manual CMB segmentation by 2 readers, and (b) public dataset (57 SWI scans from 30 patients with Alzheimer’s and CMB locations). The data was split into training, validation, and testing subsets (internal: 50/20/13; Public: 38/9/10). Preprocessing included N3 bias field correction, brain extraction, and up-sampling to a fixed in-plane resolution (0.2mm). Model used multi-channel 2D input (Fig1.b) and mimicked manual CMB segmentation. We trained base-model initially using the public dataset and then applied transfer learning using the internal dataset to segment CMBs in clinical scans. We evaluated model’s performance by sensitivity (S), precision (P), number of false positives per scan (FPC) and F1-score (F1).

Results:
On 10 public test scans, base model performed well (S 0.81, P 0.74, FPC 0.60, F1 0.77) but had high FPC for 13 internal test scans (S 1.00, P 0.15, FPC 4.31, F1 0.26). After transfer learning, the precision, FPC and F1-score were improved for internal scans (S 0.80, P 0.80, FPC 0.15, F1 0.80).

Conclusion:
Refined deep-learning based CMB counting algorithms could quantify CMBs for heterogeneous clinical MRI dataset with good sensitivity, precision, and false positivity. This method may accelerate further CAA clinical diagnosis and research.
Abstract TP101: Reduced Left Atrial Strain In Embolic Stroke Of Undetermined Source Is Associated With Atrial Fibrillation Detected On Mobile Cardiac Monitoring
Authors: Bashir Zubair , Chen Edward W , Wang Shuyuan , Shu Liqi , Goldstein Eric D , Rana Maheen , Kala Narendra , Dai Xing , Mandel Daniel , Yaghi Shadi , Has Phinnara , Xie Mingxing , Wang Tao , Simmons James , Song Christopher , Haines Philip
Published: February 2023

Recent studies have failed to reveal benefit of anticoagulation over antiplatelet therapy in the prevention of recurrent stroke in Embolic Stroke of Undetermined Source (ESUS) patients. This is attributed to significant heterogeneity in underlying mechanisms of ESUS. Atrial fibrillation (AF) is a potential cause of ESUS, and evaluating left atrial (LA) function by measuring LA strain by speckle tracking echocardiography (STE) is an emerging technique to assess LA biomechanics. Our study investigates the relationship between LA strain and AF detection in ESUS patients. We included hospitalized patients with ESUS subtype who underwent STE. LA function by assessing three phases of LA strain (reservoir, conduit and contractile) were retrospectively quantified and evaluated. Several patients were discharged with mobile cardiac telemetry that was retrospectively reviewed for AF detection. Descriptive statistical methods and both unadjusted and adjusted regression models were used. Among 325 ESUS patients, mean age was 66.5±15.0, 49% were male, 49% had outpatient cardiac monitoring, and 25% had AF detected. LA reservoir (25.17±13.4 vs 32.43±18.13), LA contractile (11.95±9.66 vs 16.67±10.94) and LA conduit (13.08±6.47 vs 17.20±12.21) strains were significantly lower in patients with AF detected compared to patients without AF detected. In the unadjusted binary logistic regression analysis, patients with AF detected had significantly lower LA reservoir (OR 0.967, 95% CI 0.941-0.994), LA contractile (OR 0.957, 95% CI 0.918-0.997) and LA conduit (OR 0.961, 95% CI 0.925-0.998) strains. This significance was lost after adjusting for age. Our study demonstrates that reduced LA strain is associated with subsequent detection of AF in ESUS patients. We believe that routine LA strain measurement can aid clinicians in identifying ESUS patients with high AF prevalence and thereby appropriately target patients for anticoagulation therapy to prevent subsequent strokes.