Early Ischemic Changes Research Articles

Abstract TP52: Comparison of Two Methods of the Alberta Stroke Program Early CT Score

Introduction: Alberta Stroke Program Early CT Score (ASPECTS) is a validated clinical tool to predict early ischemic changes in acute ischemic stroke (AIS). In addition to scoring of non-contrast brain CT images (CT), head CT angiogram source images (CTA) have also been demonstrated as useful for scoring. We hypothesized that CTA ASPECTS would show superior inter-rater reliability as compared to CT ASPECTS, and that both would perform better in the setting of the favorable target mismatch (TM) profile on CT perfusion imaging (CTP). Methods: We reviewed AIS patients from 2010-2014 with an acute M1 middle cerebral artery occlusion that underwent CT, CTA, and CTP imaging at hospital admission. CT and CTA were independently scored by two experienced physician raters using the standard ASPECTS methodology. Inter-rater agreement was calculated with a weighted kappa. The cohort was then further stratified into either favorable or non-favorable TM profiles using volumetric measurements from the Olea Sphere software and the DEFUSE-3 definition of TM. Results: We included 68 patients. The mean±SD age was 62±18 years. 60% were men. The mean NIH stroke scale was 14.5±7.9. The median (IQR) follow-up modified Rankin Scale (mRS) was 3 (1,6). 37 of 68 (54%) patients had the TM profile and were significantly more likely to have lower follow-up mRS scores (z=3.5, p<0.001). Inter-rater agreement of CTA ASPECTS (kappa=0.82) was superior to CT ASPECTS (kappa=0.76). Patients with the TM profile demonstrated more reliable agreement on both CTA and CT ASPECTS scoring systems (kappa=0.79, 0.78), compared to those without the TM profile (kappa=0.71, 0.75). Discussion: We found that inter-rater agreement was higher for CTA ASPECTS as compared to CT ASPECTS and that both performed better in patents with the TM profile. Clinically this is important because it reaffirms the utility of CTA ASPECTS in this population of patients in which high reliability is paramount, as ASPECTS is often used in medical decision making when determining eligibility for medical and/or endovascular thrombolytic therapies.

Abstract TP45: Predictors for Good Collaterals in 857 Patients With Acute Ischemic Stroke and Proximal Middle Cerebral Artery Occlusion

Background: Good collaterals in acute ischemic stroke (AIS) correlate with smaller infarct size, improved outcome, and better recanalization rates after revascularisation treatments. Given that the variables determining collateral circulation are poorly understood, we aimed to identify predictors of good collaterals in a large series of AIS with middle cerebral artery (MCA) occlusion. Methods: In the Acute STroke Registry and Analysis of Lausanne (ASTRAL) from 2003 to 2016, we identified all AIS with MCA occlusion (M1 or proximal M2) on CT angiography (CTA) performed within 24 hours. Collaterals were graded from 0 (absent) to 3 (100% or more) and classified as good (grades 2 and 3) or poor. We correlated collateral status with various clinical, metabolic and radiological variables in a univariate, then multivariate regression analyses (MVA). Results: Of the 2’027 patients with AIS involving the MCA and good quality CTA during the study period, 857 met the inclusion criteria. Median age was 72.3±20.5 years, 48.4% were females, and median admission NIHSS was 16±9. Younger age (OR=0.99, confidence interval (CI) 0.98-0.99) and lower NIHSS on admission (OR=0.92, CI=0.90-0.94) were significantly associated with good collaterals. Hyperglycemia (OR=0.94, CI=0.88-0.99) and higher creatininemia (OR=0.99, CI=0.99-1) correlated with poor collaterals. The distribution of vascular risk factors was similar. Radiologically, good collateral status was predicted by higher ASPECTS score (OR=1.31, CI=1.24-1.40), absence of a hyperdense MCA sign (OR=0.60, CI=0.46-0.79), lower clot burden (OR=1.18, CI=1.12-1.24) and absence of proximal intracranial arterial pathology (OR=0.44, CI=0.33-0.58). MVA results will be presented. Conclusion: Good collaterals are associated with lower age and lower NIHSS, whereas high blood glucose and creatinine values predicted poor collaterals. On neuroimaging, minor early ischemic changes, lower clot burden and distal site of vascular occlusion correlated with good collaterals. These data may predict stroke outcome in certain patients, explain futile recanalisation, and help select patients for late or aggressive recanalisation treatments independently of time windows.

Abstract TP51: When Can Aspects be Read Reliably?

Introduction: Alberta Stroke Program Early CT Score (ASPECTS) is a systematic approach to assess early ischemic change on non-contrast CT (NCCT). Concerns have however been expressed about its reliability when making clinical decisions in patients with acute ischemic stroke. We chose to systematically assess technical, environmental and patient specific variables that potentially affect ASPECTS interpretation. Methods: We randomly selected 150 patients with acute ischemic stroke from the PRoveIT database. All patients had baseline NCCT and CT angiography head and neck. Three raters (expert, fellow and trainee) read ASPECTS on the same NCCT three times (Sessions 1-3) at minimum interval of 10-14 days. Raters were kept blinded to follow-up data throughout the study. No baseline clinical information was provided in Session 1. Raters were provided clinical information (age, baseline NIHSS and side of stroke) in session 2 and additional multiphase CTA in session 3. Reading environment [room light and time pressure (<60 s for interpretation) vs. core lab] was altered during readings. Data on motion artifact, leukoaraiosis, old infarcts on NCCT were collected. Time taken for ASPECTS interpretation was collected across all the readings. Reliability was assessed using Intra-cluster correlation coefficient (ICC). Results: The highest inter-rater reliability was found in session 3 (ICC 0.47; p<0.001). The rest of the analyses was restricted to session 3. Reliability in session 3 was not affected by time pressure or ambient light settings (all p<0.01). In session 3, patient motion (ICC 0.35 present vs. 0.49 absent) and old infarcts (ICC 0.42 present vs. 0.48 absent) worsened reliability; however presence of leukoaraiosis did not affect reliability (ICC 0.48 present vs. 0.46 absent). Mean time for ASPECT interpretation by trainee, fellow and expert were 38.9 s (+/-12.8s), 49.8 s (+/-15.4s) and 38.9 s (+/-14s) respectively. Conclusion: ASPECTS interpretation on NCCT is most reliable when clinical and CTA information is available. Interpretation with this information is reliable even in a well-lit room and under time pressure, the environment that mimics real life acute stroke.

重症くも膜下出血患者に対する血管内冷却カテーテルによる体温管理の可能性と安全性について ─低体温療法から復温後の常温管理に関する初期経験─

Fever in subarachnoid hemorrhage (SAH) is associated with vasospasm and poor outcome. To mitigate early brain damage in SAH, we have been treating World Federation of Neurological Surgeons (WFNS) Grade 5 patients with rapid induction of therapeutic hypothermia (TH) initiated immediately following onset of SAH and continued for approximately 7 days. Management after rewarming has been problematic. Rebound fever, especially during the period of post-SAH vasospasm, may increase the risk of cerebral infarction. We prospectively studied the feasibility and safety of endovascular cooling for maintaining prophylactic normothermia following initial TH in patients with severe SAH.TH (core body temperature 34.0°C) using surface cooling was initiated immediately after a diagnosis of WFNS Grade 5 SAH was made. All ruptured aneurysms were surgically clipped as soon as possible within 6 hours after arrival. At approximately postoperative day 7, after rewarming to 36°C, an endo- vascular catheter with 2 cooling balloons (Cool Line® Catheter, Asahi Kasei ZOLL Medical Corp., Tokyo, Japan) was inserted into the left internal jugular vein and connected to the Thermogard XP® Temperature Management System (Asahi Kasei ZOLL Medical Corp.) for the following 7 days. Temperature recordings in 11 SAH patients immediately before the period of endovascular cooling served as the control.Eleven patients (6 women; mean age of 63.8 ± 6.4 years [range, 50-73 years]) were enrolled in the study. Endovascular cooling was initiated at 7.9 ± 1.4 days (range, 6-11 days) after admission and continued for 6.7 ± 0.9 days (range 4-7 days). Unfavorable outcomes were associated with minimal shivering and good temperature control, whereas favorable outcomes were associated with vigorous shivering and increased temperature. Nine patients manifested shivering with increased temperature and were treated with acetaminophen, dexmedetomidine, and/or propofol. During the study period, two patients developed fevers above 38°C, and 8 of 11 patients without endovascular cooling developed fevers (p=0.03, two-tailed Fisher's exact test). There was no evidence of cerebral infarction related to vasospasm during endovascular cooling, and no catheter-related sepsis or thromboembolic events. In one patient, fasudil hydrochloride was administered intra-arterially for angiographic vasospasm, resulting in no cerebral infarction. In another patient, intensive treatment was withdrawn because of massive brain swelling; however, slight but extensive early ischemic change was retrospectively confirmed on computed tomography prior to endovascular cooling. Vasospasm-related cerebral infarction occurred in one patient 2 days after removal of the cooling catheter. In one patient, fatal bacterial meningitis related to spinal drainage occurred on Day 29. Three-month outcomes showed good recovery in 2, moderate disability in 4, severe disability in 2, vegetative state in 1, and death in 2. Amelioration of fever burden during the first 14 days after onset of SAH was safe and feasible with combined surface and endovascular cooling in patients with WFNS Grade 5 SAH.

E-ASPECTS software is non-inferior to neuroradiologists in applying the ASPECT score to computed tomography scans of acute ischemic stroke patients.

Background The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is an established 10-point quantitative topographic computed tomography scan score to assess early ischemic changes. We performed a non-inferiority trial between the e-ASPECTS software and neuroradiologists in scoring ASPECTS on non-contrast enhanced computed tomography images of acute ischemic stroke patients. Methods In this multicenter study, e-ASPECTS and three independent neuroradiologists retrospectively and blindly assessed baseline non-contrast enhanced computed tomography images of 132 patients with acute anterior circulation ischemic stroke. Follow-up scans served as ground truth to determine the definite area of infarction. Sensitivity, specificity, and accuracy for region- and score-based analysis, receiver-operating characteristic curves, Bland-Altman plots and Matthews correlation coefficients relative to the ground truth were calculated and comparisons were made between neuroradiologists and different pre-specified e-ASPECTS operating points. The non-inferiority margin was set to 10% for both sensitivity and specificity on region-based analysis. Results In total 2640 (132 patients × 20 regions per patient) ASPECTS regions were scored. Mean time from onset to baseline computed tomography was 146 ± 124 min and median NIH Stroke Scale (NIHSS) was 11 (6-17, interquartile range). Median ASPECTS for ground truth on follow-up imaging was 8 (6.5-9, interquartile range). In the region-based analysis, two e-ASPECTS operating points (sensitivity, specificity, and accuracy of 44%, 93%, 87% and 44%, 91%, 85%) were statistically non-inferior to all three neuroradiologists (all p-values <0.003). Both Matthews correlation coefficients for e-ASPECTS were higher (0.36 and 0.34) than those of all neuroradiologists (0.32, 0.31, and 0.3). Conclusions e-ASPECTS was non-inferior to three neuroradiologists in scoring ASPECTS on non-contrast enhanced computed tomography images of acute stroke patients.

Processing Time Reduction: an Application in Living Human High-Resolution Diffusion Magnetic Resonance Imaging Data.

High Angular Resolution Diffusion Imaging (HARDI) is a type of brain imaging that collects a very large amount of data, and if many subjects are considered then it amounts to a big data framework (e.g., the human connectome project has 20 Terabytes of data). HARDI is also becoming increasingly relevant for clinical settings (e.g., detecting early cerebral ischemic changes in acute stroke, and in pre-clinical assessment of white matter-WM anatomy using tractography). Thus, this method is becoming a routine assessment in clinical settings. In such settings, the computation time is critical, and finding forms of reducing the processing time in high computation processes such as Diffusion Spectrum Imaging (DSI), a form of HARDI data, is very relevant to increase data-processing speed. Here we analyze a method for reducing the computation time of the dMRI-based axonal orientation distribution function h by using Monte Carlo sampling-based methods for voxel selection. Results evidenced a robust reduction in required data sampling of about 50% without losing signal's quality. Moreover, we show that the convergence to the correct value in this type of Monte Carlo HARDI/DSI data-processing has a linear improvement in data-processing speed of the ODF determination. Although further improvements are needed, our results represent a promissory step for future processing time reduction in big data.

Topographic Assessment of Acute Ischemic Changes for Prognostication of Anterior Circulation Stroke.

The location of acute ischemic infarct can affect the clinical outcome of stroke patients. We aimed to develop a prognostic tool based on the topographic distribution of early ischemic changes on admission computed tomography (CT) scans. Using the albumin in acute stroke (ALIAS) trials dataset, patients with anterior circulation stroke were included for analysis. A 3-month modified Rankin scale (mRs) score > 2 defined disability/death; and ≤2 defined favorable outcome. A penalized logistic regression determined independent predictors of disability/death among components of admission CT scan Alberta Stroke Program Early CT score (ASPECTS). Follow-up 24-hour CT/MRI scans were reviewed for intracranial hemorrhage (ICH). A simplified ASPECTS (sASPECTS) was developed including the caudate, lentiform nucleus, insula, and M5 components of ASPECTS-which were independent predictors of disability/death on multivariate analysis. There was no significant difference between ASPECTS and sASPECTS in prediction of disability/death (P = .738). Among patients with sASPECTS ≥ 1, the rate of favorable outcome was higher in those with intravenous (IV) thrombolytic therapy (501/837, 59.9%) versus those without treatment (91/183, 49.7%, P = .013); whereas among patients with sASPECTS of 0, IV thrombolysis was not associated with improved outcome. Also, patients with sASPECTS of 0 were more likely to develop symptomatic ICH (odds ratio = 2.62, 95% confidence interval: 1.49-4.62), compared to those with sASPECTS ≥ 1 (P = .004). Topographic assessment of acute ischemic changes using the sASPECTS (including caudate, lentiform nucleus, insula, and M5) can predict disability/death in anterior circulation stroke as accurately as the ASPECTS; and may help predict response to treatment and risk of developing symptomatic ICH.

Abstract PR402

Background & Objectives: The incidence of perioperative cardiovascular complication is remarkable and the occurrence of postoperative myocardial ischemia within the first two days of surgery implies a nine-fold increase in risk for perioperative in-hospital cardiac complications. ECG is considered the cheapest and non-invasive tool to assess the patient immediately postoperative. However, the reliability of using such a simple tool is not clear yet. The aim of this study is to compare between the ECG 12 leads, as a standard tool, and the high sensitive Troponin (hs-TnT) level changes to predict early myocardial ischemic changes postoperatively. Materials & Methods: Thirty nine patients are recruited in this study. Parameters BP, HR, RR, PSO2, ECG and hs-TnT have been measured immediately 1 hr and 24 hr postoperatively. The respective changes were correlated to medical history, perioperative parameters and the occurrence of myocardial ischemic changes. ECG reading has been performed by a blind observer. Results: There was increase of hs-TNT level in about 18% of the patients and 23% of the patients showed ECG myocardial ischemic changes. Patients who showed ischemic changes via ECG did not correlate significantly with b hs-TNT changes. Postoperative hs-TNT measurements demonstrated significant increase between 1 hr and 24 hr postoperative (p>0.01). The diagnostic sensitivity for hc-TNT to that of ECG was very low (11.1%) with high specificity (83.3%). Conclusion: In this study, the variations in the hs-TNT levels could predict early myocardial ischemic changes, though, ECG still representing the more sensitive diagnostic tool to predict myocardial ischemic changes during the first 24 hr postoperatively.

Impact of ASPECTS on computed tomography angiography source images on outcome after thrombolysis or endovascular therapy in large vessel occlusions.

Endovascular therapy (ET) is superior to intravenous thrombolysis (IVT) in selected patients with anterior circulation large vessel occlusions. However, it is unclear if this positive effect also applies to patients with extensive early ischaemic changes. The aim of this study was to analyze the impact of the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on the CT angiography source images (SI) on outcome after ET or IVT. Using our prospectively obtained stroke database and the admission SI-ASPECTS divided into three groups (0-5, 6-7 and 8-10), primarily the rates of good outcome [modified Rankin Scale (mRS) ≤2 at discharge] after either ET (n = 255) or IVT (n = 479) were compared. A favorable SI-ASPECTS (8-10) was present in 501 patients, 132 patients had a moderately favorable SI-ASPECTS (6-7) and 101 patients had an unfavorable SI-ASPECTS (0-5). Irrespective of the treatment modality, no patient with an unfavorable SI-ASPECTS had a good outcome and 38% died during hospital stay. Whilst significantly more patients with a favorable SI-ASPECTS had a good outcome after ET than after IVT (51% vs. 35%, P < 0.01), there was only a non-significant trend towards a good outcome after ET than after IVT in patients with a moderately favorable ASPECTS (25% vs. 14%, P = 0.1). Patients with extensive early ischaemic changes on CT scans (SI- ASPECTS ≤5) might not profit from ET. The impact of ET on outcome in patients with moderately favorable SI-ASPECTS should be addressed in further trials.

Comprehensive imaging of stroke – Looking for the gold standard

Background and purposeStroke is the third cause of death worldwide. In recent decade there has been a marked progress in treatment and prevention of stroke, which was possible largely due to modern neuroimaging techniques. Early radiological confirmation of the diagnosis allows for introduction of fibrinolytic therapy and evaluation of ischaemic penumbra. Material and methodsWe have analysed clinical and imaging data of 92 patients with early stages of stroke. The sensitivity, specificity and possible influence on the choice of treatment were assessed for different neuroimaging techniques, including diffusion weighted and perfusion imaging in patients with hyperacute and acute stroke. ResultsA non-contrast computed tomography (CT) allowed for the detection of early ischaemic changes with an overall sensitivity of 38% and 42% in patients in hyperacute phase. In a perfusion CT study the perfusion abnormalities in the area corresponding to the clinical symptoms were present in 79% of patients. The sensitivity of diffusion weighted imaging (DWI) alone was 95% and in conjunction with perfusion MR reached 100%. ConclusionsOur study proves that advanced neuroimaging modalities allow for a substantial increase of sensitivity when detecting changes in patients with acute ischaemic strokes and confirming the clinical diagnosis. We believe that MR in combination with DWI should be the imaging methods of choice in diagnosing acute stroke patients. Perfusion adds significant diagnostic value to structural techniques, particularly in clinically ambiguous cases. In cases with a clear clinical picture the data provided by a non-contrast CT study is sufficient for therapeutic decision making.

Abstract TP56: The Impact of Early Ischemic Changes on Head CT on Hemorrhagic Conversion and Outcomes in Patients With Acute Ischemic Stroke

Background: Early ischemic changes (EIC) on head CT are associated with increased hemorrhagic transformation (HT) following treatment with TPA. We examined the associations between EIC, HT, and outcomes in patients treated and not treated with IV TPA. Methods: We conducted a retrospective review of consecutive acute ischemic stroke (AIS) patients presenting to our CSC from April 2014 to March 2015. Demographic and clinical data, including initial head CT findings (parenchymal hypodensity, loss of gray-white differentiation, sulcal effacement, hyperdense vessel) were collected. HT on repeat neuroimaging, poor functional outcome, as measured by a modified Rankin Scale (mRS) of 3-6, and in-hospital mortality were assessed. Results: A total of 679 patients were included (50.4% men). One hundred and eight patients (15.9%) received IV TPA. EIC were observed in 38.5% of untreated patients and 17.6% in IV TPA treated patients (p&lt;0.0001). For patients treated with IV TPA, EIC was seen more frequently in patients with pre-stroke anticoagulant use (26.3% vs. 6.7%, p=0.010) and less frequently in patients with pre-stroke statin use (15.8% vs. 43.3%, p=0.025). A higher proportion of HT was observed in patients with EIC (12.8% vs. 6.8%, p=0.016 untreated, 36.8% vs. 14.6%, p=0.024 IV TPA) and with hyperdense artery sign (8.2% vs. 3.7%, p=0.022 untreated, 36.8% vs. 15.7%, p=0.035 IV TPA). For untreated patients, EIC was observed in a larger proportion of patients with an NIHSS&gt;14 (14.8% vs. 9.6%, p=0.016), and discharge mRS 3-6 (53.6% vs. 44.5%, p=0.040). For patients treated with IV TPA, in-hospital mortality was more common in patients with EIC (31.6% vs. 10.0%, p=0.013). Conclusions: In untreated patients, EIC may serve as a harbinger for HT on repeat imaging and poor functional outcome at discharge, whereas in patients treated with IV TPA, it is associated with HT and in-hospital mortality. Patients with EIC may be at increased risk of HT and poor outcomes even without thrombolytics.

Abstract WP54: Evaluation of the e-ASPECTS Automated Software for Detection of Acute Ischemic Stroke

Objective: The Alberta Stroke Program Early CT score (ASPECTS)method is a validated score for identifying patients more likely to benefit from either thrombolytic or endovascular therapy. The e-ASPECTS software is a new, commercially available, standardized and fully automated ASPECTS scoring tool. e-ASPECTS assesses signs of early ischemic change on plain CT scans of stroke patients by applying the ASPECTS method. We compared the performance of e-ASPECTS to CT perfusion in detecting early ischemic signs. Methods: e-ASPECTS was run on the plain CT scans of 20 patients with acute ischemic stroke. CT perfusion, CT angiography and 24h CT was also available. The ischemic damage identified by e-ASPECTS was compared to the ischemic core as depicted on CBV on CT perfusion and the established infarct core on plain CT at 24h. Findings: e-ASPECTS reliably depicted established ischemic damage as compared to CT-Perfusion, both on an region-based and ASPECTS-based analysis. Conclusion: This is the first report demonstrating that e-ASPECTS correctly identified infarct on plain CT, similar to CT perfusion.

Evaluation of early ischemic changes in stroke patients treated with thrombolytic therapy

Introduction: The aim of this study is to evaluate early brain ischemic changes on CT scan in stroke patients in correlation with the clinical outcome, as well as to evaluate if there is prognostic and predicti- ve features that can be used. Patients and methods: We examined 20 patients with acute ischemic stroke, from which 12 were male and 8 were female, at the age from 47 to 76 years. Results: The hyperdense medial artery (HMA) sign was present in 10 (50%) patients. Concerning the ASPECTS score, 5 patients (25%) had normal score of 10 points, while 7 patients (35%) had score of 7 points. 12 patients (60%) had unfavorable outcome, while 8 patients (40%) had favorable outco- me. Our statistical analysis shows that age of more than 65 years, presence of 2 or more risk-factors, ASPECTS score of 7 and presence of HMA sign were all statisti- cally significant predictors of unfavorable outcome in examined patients (p < 0.05 each). The presence of the hyperdense medial artery sign was the most significant single predictor for unfavorable clinical outcome (p = 0.0042, p < 0.05). Conclusion: The presence of HMA sign is the most significant single predictor for unfavo- rable clinical outcome.

Scientific Rationale for the Inclusion and Exclusion Criteria for Intravenous Alteplase in Acute Ischemic Stroke: A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association.

To critically review and evaluate the science behind individual eligibility criteria (indication/inclusion and contraindications/exclusion criteria) for intravenous recombinant tissue-type plasminogen activator (alteplase) treatment in acute ischemic stroke. This will allow us to better inform stroke providers of quantitative and qualitative risks associated with alteplase administration under selected commonly and uncommonly encountered clinical circumstances and to identify future research priorities concerning these eligibility criteria, which could potentially expand the safe and judicious use of alteplase and improve outcomes after stroke. Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and the American Heart Association's Manuscript Oversight Committee. The writers used systematic literature reviews, references to published clinical and epidemiology studies, morbidity and mortality reports, clinical and public health guidelines, authoritative statements, personal files, and expert opinion to summarize existing evidence and to indicate gaps in current knowledge and, when appropriate, formulated recommendations using standard American Heart Association criteria. All members of the writing group had the opportunity to comment on and approved the final version of this document. The document underwent extensive American Heart Association internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee. After a review of the current literature, it was clearly evident that the levels of evidence supporting individual exclusion criteria for intravenous alteplase vary widely. Several exclusionary criteria have already undergone extensive scientific study such as the clear benefit of alteplase treatment in elderly stroke patients, those with severe stroke, those with diabetes mellitus and hyperglycemia, and those with minor early ischemic changes evident on computed tomography. Some exclusions such as recent intracranial surgery are likely based on common sense and sound judgment and are unlikely to ever be subjected to a randomized, clinical trial to evaluate safety. Most other contraindications or warnings range somewhere in between. However, the differential impact of each exclusion criterion varies not only with the evidence base behind it but also with the frequency of the exclusion within the stroke population, the probability of coexistence of multiple exclusion factors in a single patient, and the variation in practice among treating clinicians.

Successful endovascular stroke therapy in a 103-year-old woman

People older than 80 years of age constitute the most rapidly growing age group in the world. Several trials confirming superior efficacy of endovascular therapy did not have an upper...

Gray-Matter Volume Estimate Score: A Novel Semi-Automatic Method Measuring Early Ischemic Change on CT.

Background and PurposeWe developed a novel method named Gray-matter Volume Estimate Score (GRAVES), measuring early ischemic changes on Computed Tomography (CT) semi-automatically by computer software. This study aimed to compare GRAVES and Alberta Stroke Program Early CT Score (ASPECTS) with regards to outcome prediction and inter-rater agreement.MethodsThis was a retrospective cohort study. Among consecutive patients with ischemic stroke in the anterior circulation who received intra-arterial therapy (IAT), those with a readable pretreatment CT were included. Two stroke neurologists independently measured both the GRAVES and ASPECTS. GRAVES was defined as the percentage of estimated hypodense lesion in the gray matter of the ipsilateral hemisphere. Spearman correlation analysis, receiver operating characteristic (ROC) comparison test, and intra-class correlation coefficient (ICC) comparison tests were performed between GRAVES and ASPECTS.ResultsNinety-four subjects (age: 68.7±10.3; male: 54 [54.9%]) were enrolled. The mean GRAVES was 9.0±8.9 and the median ASPECTS was 8 (interquartile range, 6-9). Correlation between ASPECTS and GRAVES was good (Spearman’s rank correlation coefficient, 0.642; P<0.001). ROC comparison analysis showed that the predictive value of GRAVES for favorable outcome was not significantly different from that of ASPECTS (area under curve, 0.765 vs. 0.717; P=0.308). ICC comparison analysis revealed that inter-rater agreement of GRAVES was significantly better than that of ASPECTS (0.978 vs. 0.895; P<0.001).ConclusionsGRAVES had a good correlation with ASPECTS. GRAVES was as good as ASPECTS in predicting a favorable clinical outcome, but was better than ASPECTS regarding inter-rater agreement. GRAVES may be used to predict the outcome of IAT.

Infarction Distribution Pattern in Acute Stroke May Predict the Extent of Leptomeningeal Collaterals.

ObjectiveThe aim of this study was to evaluate whether the distribution pattern of early ischemic changes in the initial MRI allows a practical method for estimating leptomeningeal collateralization in acute ischemic stroke (AIS).MethodsSeventy-four patients with AIS underwent MRI followed by conventional angiogram and mechanical thrombectomy. Diffusion restriction in Diffusion weighted imaging (DWI) and correlated T2-hyperintensity of the infarct were retrospectively analyzed and subdivided in accordance with Alberta Stroke Program Early CT score (ASPECTS). Patients were angiographically graded in collateralization groups according to the method of Higashida, and dichotomized in 2 groups: 29 subjects with collateralization grade 3 or 4 (well-collateralized group) and 45 subjects with grade 1 or 2 (poorly-collateralized group). Individual ASPECTS areas were compared among the groups.ResultsMeans for overall DWI-ASPECTS were 6.34 vs. 4.51 (well vs. poorly collateralized groups respectively), and for T2-ASPECTS 9.34 vs 8.96. A significant difference between groups was found for DWI-ASPECTS (p<0.001), but not for T2-ASPECTS (p = 0.088). Regarding the individual areas, only insula, M1-M4 and M6 showed significantly fewer infarctions in the well-collateralized group (p-values <0.001 to 0.015). 89% of patients in the well-collateralized group showed 0–2 infarctions in these six areas (44.8% with 0 infarctions), while 59.9% patients of the poor-collateralized group showed 3–6 infarctions.ConclusionPatients with poor leptomeningeal collateralization show more infarcts on the initial MRI, particularly in the ASPECTS areas M1 to M4, M6 and insula. Therefore DWI abnormalities in these areas may be a surrogate marker for poor leptomeningeal collaterals and may be useful for estimation of the collateral status in routine clinical evaluation.

Fast Door-to-Needle Times for an MRI-Based Acute Stroke Protocol

The initial acute stroke evaluation typically includes a noncontrast computed tomography (CT) to assess for intracerebral hemorrhage and early ischemic changes. Although magnetic resonance imaging (MRI) provides more information on the distribution and extent of acute ischemia, the concerns about the cost and complexity of the infrastructure required to provide immediate access to MRI and the potential for introducing treatment delays have …

Value of Whole Brain Computed Tomography Perfusion for Predicting Outcome after TIA or Minor Ischemic Stroke

About 15% of patients with transient ischemic attack (TIA) or minor ischemic stroke have functional impairment after 3 months. We studied the role of whole brain computed tomography perfusion (WB-CTP) in the emergency diagnosis of TIA or minor stroke in predicting disability at 3 months. We included patients with ongoing symptoms of a TIA or minor stroke with a National Institutes of Health Stroke Scale (NIHSS) score less than 4 who were evaluated with noncontrast CT (NCCT), CT angiography (CTA), and WB-CTP within 24 hours of symptom onset. Patients treated with thrombolysis or a premorbid modified Rankin Scale (mRS) score greater than 1 were excluded. The association between clinical or imaging features and disability (mRS score ≥2) at 3 months was analyzed with Poisson regression. Potential additional prognostic value of WB-CTP was assessed with logistic regression. We included 115 patients in 2012 to 2013. Median age was 68 years, and 66% were men. At 3 months, 20 patients (17%) were disabled. NIHSS score on admission (relative risk [RR], 3.6; 95% confidence interval [CI], 1.4-9.3), female sex (RR, 2.4; 95% CI, 1.1-5.3), early ischemic changes on NCCT (RR, 5.0; 95% CI, 2.6-9.9), extracranial or intracranial vessel stenosis ≥50% on CTA (RR, 3.0; 95% CI, 1.4-6.4), and perfusion abnormalities on WB-CTP (RR, 11.4; 95% CI, 4.6-28.2) were associated with disability at 3 months. In multivariable analysis, the relation between perfusion abnormalities and poor outcome remained essentially the same. WB-CTP showed prognostic value in addition to proved clinical and imaging predictors of disability. WB-CTP is useful to identify patients with TIA or minor ischemic stroke at high risk of functional impairment at 3-month follow-up.

Improving the Prediction of Spontaneous and Post-thrombolytic Recanalization in Ischemic Stroke Patients

Endovascular treatment for acute ischemic stroke patients was recently shown to improve recanalization rates and clinical outcome in a well-defined study population. Intravenous thrombolysis (IVT) alone is insufficiently effective to recanalize in certain patients or of little value in others. Accordingly, we aimed at identifying predictors of recanalization in patients treated with or without IVT. In the observational Acute Stroke Registry and Analysis of Lausanne (ASTRAL) registry, we selected those stroke patients (1) with an arterial occlusion on computed tomography angiography (CTA) imaging, (2) who had an arterial patency assessment at 24 hours (CTA/magnetic resonance angiography/transcranial Doppler), and (3) who were treated with IVT or had no revascularization treatment. Based on 2 separate logistic regression analyses, predictors of spontaneous and post-thrombolytic recanalization were generated. Partial or complete recanalization was achieved in 121 of 210 (58%) thrombolyzed patients. Recanalization was associated with atrial fibrillation (odds ratio , 1.6; 95% confidence interval, 1.2-3.0) and absence of early ischemic changes on CT (1.1, 1.1-1.2) and inversely correlated with the presence of a significant extracranial (EC) stenosis or occlusion (.6, .3-.9). In nonthrombolyzed patients, partial or complete recanalization was significantly less frequent (37%, P < .01). The recanalization was independently associated with a history of hypercholesterolemia (2.6, 1.2-5.6) and the proximal site of the intracranial occlusion (2.5, 1.2-5.4), and inversely correlated with a decreased level of consciousness (.3, .1-.8), and EC (.3, .1-.6) and basilar artery pathology (.1, .0-.6). Various clinical findings, cardiovascular risk factors, and arterial pathology on acute CTA-based imaging are moderately associated with spontaneous and post-thrombolytic arterial recanalization at 24 hours. If confirmed in other studies, this information may influence patient selection toward the most appropriate revascularization strategy.