Absence Of Large Vessel Occlusion Research Articles

DEEP MOVEMENT: Deep learning of movie files for management of endovascular thrombectomy

ObjectivesTreatment and outcomes of acute stroke have been revolutionised by mechanical thrombectomy. Deep learning has shown great promise in diagnostics but applications in video and interventional radiology lag behind. We aimed to develop a model that takes as input digital subtraction angiography (DSA) videos and classifies the video according to (1) the presence of large vessel occlusion (LVO), (2) the location of the occlusion, and (3) the efficacy of reperfusion.MethodsAll patients who underwent DSA for anterior circulation acute ischaemic stroke between 2012 and 2019 were included. Consecutive normal studies were included to balance classes. An external validation (EV) dataset was collected from another institution. The trained model was also used on DSA videos post mechanical thrombectomy to assess thrombectomy efficacy.ResultsIn total, 1024 videos comprising 287 patients were included (44 for EV). Occlusion identification was achieved with 100% sensitivity and 91.67% specificity (EV 91.30% and 81.82%). Accuracy of location classification was 71% for ICA, 84% for M1, and 78% for M2 occlusions (EV 73, 25, and 50%). For post-thrombectomy DSA (n = 194), the model identified successful reperfusion with 100%, 88%, and 35% for ICA, M1, and M2 occlusion (EV 89, 88, and 60%). The model could also perform classification of post-intervention videos as mTICI < 3 with an AUC of 0.71.ConclusionsOur model can successfully identify normal DSA studies from those with LVO and classify thrombectomy outcome and solve a clinical radiology problem with two temporal elements (dynamic video and pre and post intervention).Key Points• DEEP MOVEMENT represents a novel application of a model applied to acute stroke imaging to handle two types of temporal complexity, dynamic video and pre and post intervention.• The model takes as an input digital subtraction angiograms of the anterior cerebral circulation and classifies according to (1) the presence or absence of large vessel occlusion, (2) the location of the occlusion, and (3) the efficacy of thrombectomy.• Potential clinical utility lies in providing decision support via rapid interpretation (pre thrombectomy) and automated objective gradation of thrombectomy outcomes (post thrombectomy).

The FAST VAN for Field Identification of Large Vessel Occlusion in Acute Stroke.

There is definitive evidence for effectiveness of thrombectomy for acute stroke with large vessel occlusion (LVO). A clinical tool to identify patients with LVO is therefore required for effective triage and prehospital decision making. We developed the FAST VAN tool, which follows from the Heart and Stroke Foundation FAST stroke screen, with the addition of cortical features of vision, aphasia, and neglect, to differentiate from lacunar syndromes. Consecutive acute stroke alerts initiated by emergency medical services (EMS) were prospectively analyzed from April 2017 to Jan 2021. FAST VAN signs were recorded by first responders who had received online education about the tool. These findings were compared to the presence or absence of LVO on CT angiography. Analysis was also performed by appropriateness for comprehensive stroke centers (CSC) transfer if no LVO was present. EMS providers were surveyed regarding ease of use in terms of learning the tool and using in real-world practice. Data from 1080 consecutive acute strokes included 440 patients considered to have VAN signs by EMS. Fifty-four percent of VAN-positive patients showed LVO on CTA. Sensitivity, specificity, and accuracy were 86%, 75%, and 77%, respectively. In 204 false-positive cases, 143 (70%) were considered appropriate for evaluation at the CSC. EMS providers reported high satisfaction with learning and using the tool. The FAST VAN tool for identification of LVO meets desired characteristics of an effective screening tool in ease of use, efficiency, and accuracy. Aphasia remains the most challenging cortical feature to identify accurately.

Abstract TP45: Promoting High Value Care For Stroke Patients Within A Stroke System Of Care: Reducing Unnecessary Hospital Transfers For Patients Not Taken For Thrombectomy

Introduction: High value care aims to provide the best patient outcomes while avoiding defects and waste. Our previous work determined that 39% of patients transferred for possible thrombectomy based on clinical criteria and CT only did not have a large vessel occlusion (LVO) which led to a health system-wide guideline to improve transfer selection by adding criteria for emergent CT angiography. This study aims to describe the impact of that guideline and reanalyze the reasons why patients transferred for consideration of thrombectomy do not receive the procedure. Methods: All patients transferred from within and outside of the health system as a potential thrombectomy candidate between 1/1/19- 6/30/21 were reviewed for reasons why thrombectomy was not pursued. Results: Over 30 months, 316 patients transferred for possible thrombectomy were not taken to the angio suite primarily due to absence of LVO on vessel imaging (26.3%), lack of suspicion of LVO on assessment (18%) and significant improvement in clinical symptoms (12%). Other reasons included too large of core infarct (13.3%), CT head ASPECT score (8.2%), lack of perfusion imaging mismatch (6.3%), poor baseline functional status (4.7%), lesion too distal (3.8%), ICH (3.2%), time since last known well (1.9%), chronic ICA occlusion preventing access to acute lesion (1.9%), and medically unstable (0.3%). Conclusions: Despite the institution of a system-wide protocol for acute CTA imaging to guide patient selection, the major reason for not proceeding to thrombectomy was still absence of LVO, some of which was related to out-of-system hospital transfers. Drawbacks of unnecessary patient transfer include increased cost of care, moving patients farther away from their home and family, and non-essential use of tertiary hospital bed space, particularly in the setting of a pandemic. Given the prevalence of potentially preventable unnecessary transfers, protocols that support in-the-field triage and transport based on clinical criteria alone, without CT or CTA, are destined to worsen health system efficiency and decrease the value of care for patients with major acuteischemic stroke.

Using a Smartphone Application for the Accurate and Rapid Diagnosis of Acute Anterior Intracranial Arterial Occlusion: Usability Study.

BackgroundTelestroke has developed rapidly as an assessment tool for patients eligible for reperfusion therapy.ObjectiveTo investigate whether vascular neurologists can diagnose intracranial large vessel occlusion (LVO) as quickly and accurately using a smartphone application compared to a hospital-based desktop PC monitor.MethodsWe retrospectively enrolled 108 consecutive patients with acute ischemic stroke in the middle cerebral artery territory who underwent magnetic resonance imaging (MRI) within 24 hours of their stroke onset. Two vascular neurologists, blinded to all clinical information, independently evaluated magnetic resonance angiography and fluid-attenuated inversion recovery images for the presence or absence of LVO in the internal carotid artery and middle cerebral artery (M1, M2, or M3) on both a smartphone application (Smartphone-LVO) and a hospital-based desktop PC monitor (PC-LVO). To evaluate the accuracy of an arterial occlusion diagnosis, interdevice variability between Smartphone-LVO and PC-LVO was analyzed using κ statistics, and image interpretation time was compared between Smartphone-LVO and PC-LVO.ResultsThere was broad agreement between Smartphone-LVO and PC-LVO evaluations regarding the presence or absence of arterial occlusion (Reader 1: κ=0.94; P<.001 vs Reader 2: κ=0.89; P<.001), and interpretation times were similar between Smartphone-LVO and PC-LVO.ConclusionsThe results indicate the evaluation of neuroimages using a smartphone application can provide an accurate and timely diagnosis of anterior intracranial arterial occlusion that can be shared immediately with members of the stroke team to support the management of patients with hyperacute ischemic stroke.

Abstract P107: Intraluminal Carotid Thrombosis and Acute Ischemic Stroke Associated With COVID-19

Background: Intraluminal carotid thrombi (ILT) are uncommon and present in only 0.4 to 1.5 % of patients with stroke. The endothelial inflammation and hypercoagulable state associated with COVID-19 (caused by SARS-CoV-2) poses a risk of arterial and venous thromboembolism. Herein, we present a series of stroke patients with ILT in the setting of a recent SARS-CoV-2 infection. Methods and Results: From July 9 th , 2020 to August 17 th , 2020, four patients were identified with acute ischemic stroke with varying thrombus burden but similar morphological patterns of ILT. All patients had evidence of recent SARS-CoV-2 infection as confirmed by PCR (n=3) or IgG antibody (n=1) in addition to clinical and radiological manifestations consistent with COVID-19. General characteristics and imaging of the patients are shown in table 1. Mean age was 55.3 ±7.7 years. Most patients (3) had at least two vascular risk factors and none had a central embolic source other than ILT. D-Dimer was profoundly elevated in 3 patients. ILT involved the cervical (3) and intracranial (1) internal carotid artery. COVID-19 symptoms ranged from mild transient respiratory symptoms to severe pneumonia requiring critical care support. None of the patients received acute reperfusion therapy either due to presentation beyond the therapeutic window or due to the absence of large vessel occlusion and/or unfavorable imaging profile. Conclusion: In this small case series of relatively young patients with acute ischemic stroke we found an association between COVID-19 infection and ILT. This suggests a distinctive pathophysiological pattern of stroke in COVID-19 patients. Further studies are necessary to elucidate the underlying pathophysiology and target specific treatment modalities.

Interfacility transfer for mechanical thrombectomy – Direct to neuroangiography or CT angiography first?

Background and purposeFaster time to mechanical thrombectomy (MT) improves outcome in stroke. In patients from other hospitals where a CT has ruled-out hemorrhage, transfer direct-to-angiography (DTA) may reduce door-to-groin time compared to transfer to CT angiography (CTA)+/−repeat CT first. However, this may result in unnecessary catheter angiography. We sought to determine how often CTA+/−CT changed the decision to proceed to MT. MethodsData on patients transferred to our comprehensive stroke center (CSC) from outside facilities for possible MT from 7/2016–5/2017 was extracted from a prospective database and supplemented with chart review. ResultsOf 170 patients transferred for MT undergoing CT+/−CTA on CSC arrival, MT was aborted in 108 (64%). Of these, 87 (81%) were aborted directly based on imaging findings, with absence of large vessel occlusion or occlusion too distal to be amenable to MT the most common reasons (n = 76), followed by extensive early CT changes (n = 9) and ICH post-tPA (n = 2). Even with NIHSS ≥10 on CSC arrival, MT was aborted based on imaging findings in 35% patients. Time from symptom onset dichotomized as early/late based on median onset-to-CSC arrival (253 min) was an important modifier of proceeding to MT in this group, with 71% of early presenters going to MT compared to 33% of late presenters (p = .003). ConclusionsTransfer DTA may result in many patients who would have been excluded based on CT+/−CTA findings undergoing unnecessary catheter angiography. However, a target population for a DTA approach might be identifiable based on severity of deficit and time from onset.

Abstract WP83: Stroke Severity and Collaterals are Associated With Infarct Progression During Inter-Facility Transfer for Endovascular Thrombectomy

Introduction: Endovascular therapy (EVT) improves clinical outcomes in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Transfer from a referring hospital (RH) to a comprehensive stroke center (CSC) renders some patients ineligible for EVT due to infarct expansion. We evaluated the association of clinical and imaging factors, and the effect of time on infarct expansion using CT ASPECTS decay, subsequent impact on thrombectomy decision and consequent clinical outcomes. Methods: We retrospectively analyzed data on patients with AIS from LVO transferred for potential EVT from a RH to our comprehensive stroke center (hub) between September 2015 and December 2017. Patients were stratified into two groups, CT decay vs. CT non-decay, where CT ASPECTS decay was defined as deterioration of score from ≥6 at RH to &lt;6 at hub (since AHA guidelines for EVT are ASPECTS &gt; 6). Baseline characteristics, clinical and imaging variables were assessed for association with decay. Good outcomes (90 day mRS 0-2) were compared between the two groups. Multivariable logistic regression was applied to identify the independent predictors for decay and the adjusted odds ratio (aOR) was calculated. Results: Of a total 154 patients, 32 (21%) had ASPECTS decay. Baseline characteristics were similar in both groups except patients with decay had higher NIHSS [Median (IQR), 21(16, 25) vs. 16 (11, 21); P &lt;. 001] and poor collateral scores (mTICI 0-1) [n (%) 17 (68) vs. 22 (29); P 0.003]. Of the 101 patients that did not undergo EVT on arrival to hub, 26 were due to decay in ASPECTS, 20 due to absence of LVO and 19 due to clinical improvement. Transfer time was similar in patients with decay vs. non-decay [Median (IQR), minutes, 164 (124.5, 198.5) vs. 155.5 (117, 191); P 0.64]. Higher initial NIHSS [aOR 1.12 (95% CI: 1.03, 1.23); P 0.009] and poor collateral score [aOR 4.65 (95% CI: 1.65, 13.07); P 0.004] were associated with decay. None of the patients with decay had a good outcome [n (%), 0 (0) vs.41 (41); P &lt;0.0001]. Conclusion: In patients transferred for potential EVT, severity of stroke at initial presentation and poor collateral circulation had significant impact on ASPECTS deterioration. This information can be employed to develop stroke systems of care to triage patients with LVO to a CSC

Usefulness of multiparametric computerised tomography findings in the differential diagnosis of stroke mimics of epileptic origin: A preliminary study

ObjectiveThirty percent of the patients for whom code stroke is activated have stroke mimics, the most common being epilepsy. Our purpose was to evaluate the usefulness of multiparametric CT for differentiating between seizure-related symptoms and vascular events. Material and methodsWe conducted a retrospective observational study; data were gathered prospectively during one year. We studied multiparametric CT images of patients admitted following code stroke activation and finally diagnosed with epilepsy. ResultsThe study included a total of 11 patients; 36% were men and mean age was 74.5 years. Three patients had right hemisphere syndrome, 4 displayed left hemisphere syndrome, and the remaining 4 had isolated aphasia. Maximum time from symptom onset to multiparametric CT study was 8.16hours. Perfusion CT results were normal in 2 patients. Nine patients showed longer or shorter times to peak (Tmax); cerebral blood volume (CBV) and cerebral blood flow (CBF) maps varied. EEG was performed a maximum of 47.6hours after symptom onset. Four patients showed findings compatible with status epilepticus, 2 displayed focal epileptiform activity, and 5 showed post-ictal slowing ipsilateral to perfusion CT abnormalities. ConclusionThe most sensitive parameter for differentiating between stroke and epilepsy in our series was increased time to peak in multilobar cortical locations in the absence of large-vessel occlusion and basal ganglia involvement. Multiparametric CT is a fast, readily available, and useful tool for the differential diagnosis of acute-onset neurological signs of epileptic origin in patients initially attended after code stroke activation.

Patterns of Stroke Transfers and Identification of Predictors for Thrombectomy

Interhospital transfers for endovascular thrombectomy (EVT) evaluation have increased since the publication of landmark neuroendovascular stroke trials in 2015. The lack of guidelines to select potential EVT candidates prior to transfer can lead to instances where, despite considerable costs and transport risks, transferred patients do not ultimately undergo EVT. Our aim was to characterize the patterns and identify predictors for EVT on transfer. In this observational cohort study, we retrospectively analyzed patients with acute ischemic stroke (AIS) transferred to our institution for EVT evaluation from January 2015 to March 2016. Clinical and radiographic predictors for EVT on transfer were determined with multivariable logistic regression analysis. A total of 103 transfer patients with AIS were included in the study, and 52% were women. A higher collateral score (P < 0.01), a higher National Institutes of Health Stroke Scale (NIHSS) score (P < 0.01), computed tomography angiography (CTA) at referring hospital (P < 0.01), and large vessel occlusion on arrival CTA (P < 0.01) were significant in patients who underwent EVT on univariable analysis. More than half (61.1%) of transfers were futile and primarily related to absence of large vessel occlusion on arrival. A higher collateral score (P= 0.02), a higher NIHSS score (P= 0.006), and having undergone a CTA at the referring center (P= 0.002) remained the independent predictors of EVT. The C statistic for the model was 0.94. A higher collateral score, the acquisition of CTA imaging at the referring centers, and a higher NIHSS score independently predicted EVT on transfer.

The Sustained DeyeCOM Sign as a Predictor of Large Vessel Occlusions and Stroke Mimics

Rapid imaging in acute stroke is critical and often occurs before full examination. Early, reliable examination findings clarify diagnosis and improve treatment times. The DeyeCOM sign has been described as a predictor of ischemic stroke. In this study, we evaluate a sustained DeyeCOM sign on serial computed tomography scans in prediction of large vessel occlusion. Between April and June 2017, we retrospectively reviewed 46 patients with acute stroke from the University of California, San Diego Stroke Registry, who had both computed tomography and computed tomography angiography as part of their acute work-up. A DeyeCOM(+) sign was defined as a conjugate gaze deviation on imaging of at least 15°. DeyeCOM(++) was defined as sustained gaze deviation on both scans. Three groups of patients were observed: DeyeCOM(++), nonsustained gaze deviation, and no gaze deviation (DeyeCOM(--)). All patients in the DeyeCOM(++) (8 of 8, 100%) had large vessel occlusion. Of those with nonsustained gaze deviation, 2 of 7 (29%) had large vessel occlusion. No patients in the DeyeCOM(--) (0 of 31, 100%) had large vessel occlusion. The specificity and sensitivity of DeyeCOM(++) for large vessel occlusion was 100% (confidence interval [CI] .90-1.0) and 80% (CI .44-.97). The specificity and sensitivity of DeyeCOM(--) for absence of large vessel occlusion was 100% (CI .69-1.0) and 86% (CI .70-.95). DeyeCOM(++) had 100% specificity for large vessel occlusion, whereas DeyeCOM(--) had a 100% specificity for absence of large vessel occlusion. Sustained DeyeCOM, whether positive or negative, is a strong predictor of ultimate diagnosis that could lead to quicker endovascular treatment times.

Abstract WMP1: Eligibility for Endovascular Trial Enrollment in the 6-24 Hour Time Window: Analysis of a Single Comprehensive Stroke Center

Background and Purpose: Recent completion of the DAWN trial supports the benefit of endovascular therapy in patients presenting in the 6-24 hour time window with anterior circulation large vessel occlusions. The scope and impact of these results on clinical practice remain unknown. Methods: A retrospective review of ischemic stroke admissions to a single comprehensive stroke center was performed during the enrollment period (November 2015-February 2017) to identify patients meeting criteria for DAWN eligibility. Patients presenting beyond 6 hours were further investigated to clarify reasons for trial exclusion. Results: Of the 2667 acute ischemic stroke patients admitted within the study period, 30% (n=792) presented within the 6-24 hour time window and 33% (890) had an NIHSS of 10 or higher. Of the 11% (n=298) patients meeting both criteria, trial exclusion occurred due to: absence of large vessel occlusion (LVO) (48%,n=143), presence of sub-occlusive, distal or posterior circulation LVO (18%, n=54), large core infarct or ASPECT &lt; 7 (25%, n=73) or absence of clinical core mismatch (5%, n=16), mRS &gt;1 (13%, n=38). There were 45 patients who met all DAWN criteria. Conclusions: Of all acute ischemic stroke patients presenting to a single CSC, 1.7% of patients qualified for DAWN clinical trial enrollment. Of patients with proximal anterior circulation occlusion presenting in the 6- 24 hour time window with NIHSS of 10 or higher , 29% were eligible for treatment based on DAWN criteria. These data predict an increase in thrombectomy utilization with important implications for Comprehensive Stroke Center resource utilization and stroke systems of care.

Abstract 46: Six of One, Half a Dozen of the Other: Single-Center Retrospective Comparison of Prehospital Large Vessel Occlusion Tools

Introduction: Large Vessel Occlusion (LVO) makes up about 30% of acute strokes. There are several published tools designed for detection of LVO for use in the prehospital setting. The ideal prehospital LVO tool should be simple and easy for prehospital staff to use and result in few LVO patients being missed as well as prevent over-testing and unnecessary transferring of patients without an LVO. Methods: From January 2015 to December 2016 1,108 acute ischemic stroke cases were identified; cases which did not present in the acute (&lt;24hrs from onset) period and cases which did not have angiography (CTA, MRA, or catheter angiogram) performed were excluded, leaving 973 cases for analysis. The components of the initial NIHSS evaluation was utilized to calculate various prehospital LVO scales (PASS, VAN, RACE, FAST-ED, and CPSSS). Each chart was reviewed for the presence or absence of LVO defined as M1, M2, ICA or basilar occlusion. The relative performance of each of the prehospital LVO scales were compared using 2x2 analysis. Results: In the study population, 30% were LVO positive, 24% received IV tPA, and 9% received endovascular thrombectomy. Comparison of tools using previously defined cutoff points yielded the sensitivity and specificity characteristics depicted in table 1 which are compared to the NIH Stroke Scale cutoff point of 6 which has been previously defined as optimal for LVO detection. Conclusion: In this analysis, it is evident that there are distinct trade-offs, with no tool being superior when it comes to having both optimal sensitivity and specificity. Although the NIHSS is the most sensitive tool, use of this scale is not practical in the prehospital setting. Therefore, we support the use of simple tools such as PASS and VAN given the relative ease with which these tools can be learned and applied by EMS.

Abstract TP59: The Sustained DeyeCOM Sign as a Predictor of Large Vessel Occlusion

Introduction: Rapid imaging in acute stroke is critical and often occurs before full examination. Early, reliable exam findings clarify diagnosis and improve treatment times. Suspected stroke patients typically undergo both acute non-contrast CT and CT Angiogram (CTA). The DeyeCOM sign (conjugate gaze deviation on CT) has been described as a predictor of ischemic stroke with good specificity. In this study, we further evaluate a sustained DeyeCOM sign on both CT and CTA in early prediction of anterior large vessel occlusion (LVO). Methods: We retrospectively reviewed 46 acute stroke code patients between April and June 2017 from the prospective, IRB approved UCSD Stroke Registry. Patients had both CT and CTA as part of their acute stroke work-up as standard of care. DeyeCOM(+) sign was defined as a conjugate gaze deviation on CT or CTA of at least 15 degrees measured by caliper technique on Agfa IMPAX software (v.6.6.1.3525). DeyeCOM(++) was defined as sustained gaze deviation on both CT and CTA. Results: Three groups of patients were observed: 1) gaze deviation on both CT and CTA (DeyeCOM(++)), 2) non-sustained gaze deviation (+ on CT or CTA but not both), and 3) no gaze deviation (DeyeCOM(--)). All patients with DeyeCOM(++) (8/8, 100%) had anterior LVO. Of those with non-sustained gaze deviation, 2/7 (29%) had LVO. No DeyeCOM(--) patients (0/31, 100%) had LVO. Of the DeyeCOM(--) patients, 16/31 (52%) were stroke mimics and 15/31 (48%) had strokes that were not LVO. The specificity and sensitivity of DeyeCOM(++) for LVO was 100% (CI .90-1.0) and 80% (CI .44-.97). The specificity and sensitivity of DeyeCOM(--) for absence of LVO was 100% (CI .69-.10) and 86% (CI .70-.95). Conclusion: In this study, DeyeCOM(++) had 100% specificity for anterior LVO while DeyeCOM(--) had a 100% specificity for absence of LVO. DeyeCOM(++) false positive rates were low. Sustained DeyeCOM, whether positive or negative, is a strong predictor of ultimate diagnosis. These results should support practitioners’ confidence that DeyeCOM(++) reflects LVO stroke and is unlikely to be a mimic and DeyeCOM(--) patients likely do not have LVO. This data point can potentially lead to quicker endovascular treatment times. Further comparisons in this dataset are ongoing and work in a larger data set is needed.

Contrast‐enhanced sonothrombolysis in acute ischemic stroke patients without intracranial large‐vessel occlusion

Contrast-enhanced sonothrombolysis (CEST) leads to a more rapid recanalization in acute ischemic stroke caused by intracranial large-vessel occlusion (LVO). Animal studies have shown that CEST also may be safe and efficient in treating the ischemic microcirculation in the absence of LVO. The exact mechanism behind this treatment effect is not known. We aimed to assess safety and efficacy of CEST in acute ischemic stroke patients included in the Norwegian Sonothrombolysis in Acute Stroke Study (NOR-SASS) without LVO on admission CT angiography (CTA). NOR-SASS was a randomized controlled trial of CEST in ischemic stroke patients treated with intravenous thrombolysis within 4.5hours after stroke onset. Patients were randomized to either CEST or sham CEST. In this study, patients were excluded if they had partial or total occlusion on admission CTA, ultrasound-resistant bone window, had received CEST with incorrect insonation as compared to stroke location on Magnetic resonance imaging (MRI), or were stroke mimics. Of the 183 patients included in NOR-SASS, a total of 83 (45.4%) patients matched the inclusion criteria, of which 40 received CEST and 43 sham CEST. There were no patients with symptomatic intracranial hemorrhage (sICH) in the CEST group. Rates of asymptomatic ICH, microbleeds, and mortality were not increased in the CEST group. Neurological improvement at 24hours and functional outcome at 90days were similar in both groups. CEST is safe in ischemic stroke patients without intracranial LVO. There were no differences in clinical outcomes between the treatment groups.

Abstract TP279: Evaluation of Exclusions for Endovascular Intervention to Identify Clinical Practice Patterns

Background: Our five-hospital Comprehensive Stroke Program utilizes a standardized large vessel occlusion (LVO) triage that includes NIHSS &gt;10 and last known well &lt;6 hours. When these criteria are met, the ED Physician and Neuro-interventionalist determine endovascular thrombectomy (ET) eligibility. If ET is not performed, standardized exclusion criteria is documented Purpose: To evaluate patterns in exclusions for ET and identify opportunities to expand treatments. Methods: A retrospective chart review of patients who arrived within 6 hours of symptom onset over a 4- month period was conducted. Patients were divided into two groups: those who received ET and those who did not. Documented exclusions were evaluated to identify clinical practice patterns. Results: Of the 52 patients who arrived within 6 hours of symptom onset, 81% (n=42) did not receive ET. Fifty-seven percent (n=24) were excluded due to deficits too mild (NIHSS &lt; 10) and 43% (n=18) had NIHSS &gt; 10 with documented exclusions. Exclusions included 1) Lack of LVO 56% (n=10); 2) Rapid improvement or mild symptoms 6% (n=1); 3) Refusal by the patient/family 11% (n=2); 4) Other reasons documented by the physician 27% (n=4). Other reasons included CTP findings of complete infarct (1), poor collaterals with large clot extension (1), unable to access common carotid occlusion (2). None of the patients were excluded due to elevated creatinine or advanced age. Exclusions were documented by 1) Neuro-interventionalist 72% (n=13;) 2) ED Physician 6% (n=1;) 3) Primary Care 6% (n=1); 4) Radiology CTA report 16% (n=3). Conclusions: The most common reasons for ET exclusion in our cohort are non-modifiable: absence of LVO and unfavorable imaging characteristics. We identified patient/family refusal as a less common exclusion reason but one that may warrant education. Continued data collection is needed to further understand exclusion patterns and improve identification of patients that could benefit from ET.

Utilidad de la tomografía computarizada cerebral multiparamétrica en el diagnóstico diferencial de patología comicial en el código ictus. Estudio preliminar

ObjectiveThirty percent of the patients for whom code stroke is activated have stroke mimics, the most common being epilepsy. Our purpose was to evaluate the usefulness of multiparametric CT for differentiating between seizure-related symptoms and vascular events. Material and methodsWe conducted a retrospective observational study; data were gathered prospectively during one year. We studied multiparametric CT images of patients admitted following code stroke activation and finally diagnosed with epilepsy. ResultsThe study included a total of 11 patients; 36% were men and mean age was 74.5 years. Three patients had right hemisphere syndrome, 4 displayed left hemisphere syndrome, and the remaining 4 had isolated aphasia. Maximum time from symptom onset to multiparametric CT study was 8.16hours. Perfusion CT results were normal in 2 patients. Nine patients showed longer or shorter times to peak (Tmax); cerebral blood volume (CBV) and cerebral blood flow (CBF) maps varied. EEG was performed a maximum of 47.6hours after symptom onset. Four patients showed findings compatible with status epilepticus, 2 displayed focal epileptiform activity, and 5 showed post-ictal slowing ipsilateral to perfusion CT abnormalities. ConclusionThe most sensitive parameter for differentiating between stroke and epilepsy in our series was increased time to peak in multilobar cortical locations in the absence of large-vessel occlusion and basal ganglia involvement. Multiparametric CT is a fast, readily available, and useful tool for the differential diagnosis of acute-onset neurological signs of epileptic origin in patients initially attended after code stroke activation.

Intravenous thrombolysis of large vessel occlusions is associated with higher hospital costs than small vessel strokes: a rationale for developing stroke severity-based financial models

BackgroundOwing to their severity, large vessel occlusion (LVO) strokes may be associated with higher costs that are not reflected in current coding systems. This study aimed to determine whether intravenous...

Diagnosis of Lacunar Infarcts within 6 Hours of Onset by Clinical and CT Criteria Versus MRI

The diagnosis of small deep infarcts (SDIs) based on clinical and noncontrast CT findings is often employed to triage stroke patients for emergent endovascular interventions. Few studies have evaluated the accuracy of <6 hours presentation with lacunar clinical syndromes in predicting the presence of a SDI and the absence of large vessel occlusion. Consecutive patients were identified with symptoms suggestive of acute stroke, diffusion-weighted magnetic resonance imaging (DW-MRI) and CT performed within 6 hours of onset, and absence of hemorrhage on imaging. Patients were given a diagnosis of SDI if they met the defined clinical and CT criteria. Diagnoses of large vessel occlusion absent (LVOA) and final diagnoses of SDI versus non-SDI incorporated hyperacute multimodal MRI data. Of 64 patients, 15 were diagnosed as SDI at <6 hours based on clinical/CT criteria. Fourteen of 15 patients (93%) had a final diagnosis of LVOA. Ten of 15 (67%) had a final MR-DWI-confirmed diagnosis of SDI. Clinical/CT diagnosis of SDI showed sensitivity of 44%, specificity 97%, positive predictive value (PPV) 93%, and negative predictive value (NPV) of 61% in predicting LVOA and sensitivity 83%, specificity 90%, PPV 67%, and NPV 96% compared to the final diagnosis of SDI. Most patients incorrectly diagnosed with SDIs harbored small cortical branch infarcts. Diagnoses of SDI <6 hours from symptom onset based on a classic lacunar syndrome and CT criteria show only modest predictive value in predicting the presence of a small-vessel territory infarct but perform fairly well in identifying patients without large-vessel occlusions amenable to endovascular therapy.