In patients with acute ischemic stroke, more distal thrombus location, greater thrombus permeability, and longer time to recanalization assessment were associated with recanalization of arterial occlusion after administration of intravenous alteplase; among patients who did not receive alteplase, rates of arterial recanalization were low. These findings may help inform treatment and triage decisions in patients with acute ischemic stroke.

Background The Alberta Stroke Program Early CT Score (ASPECTS) is a systematic method of assessing the extent of early ischemic change on non-contrast computed tomography in patients with acute ischemic stroke. Our objective was to validate an automated ASPECTS scoring method we recently developed on a large data set. Materials and methods We retrospectively collected 602 acute ischemic stroke patients’ non-contrast computed tomography scans. Expert ASPECTS readings on non-contrast computed tomography were compared to automated ASPECTS. Statistical analyses on the total ASPECTS, region level ASPECTS, and dichotomized ASPECTS (≤4 vs. >4) score were conducted. Results In total, 602 scans were evaluated and 6020 (602 × 10) ASPECTS regions were scored. Median time from stroke onset to computed tomography was 114 min (interquartile range: 73–183 min). Total ASPECTS for the 602 patients generated by the automated method agreed well with expert readings (intraclass correlation coefficient): 0.65 (95% confidence interval (CI): 0.60–0.69). Region level analysis showed that the automated method yielded accuracy of 81.25%, sensitivity of 61.13% (95% CI: 58.4%–63.8%), specificity of 86.56% (95% CI: 85.6%–87.5%), and area under curve of 0.74 (95% CI: 0.73–0.75). For dichotomized ASPECTS (≤4 vs. >4), the automated method demonstrated sensitivity 97.21% (95% CI: 95.4%–98.4%), specificity 57.81% (95% CI: 44.8%–70.1%), accuracy 93.02%, and area under the curve of 0.78 (95% CI: 0.74–0.81). For each individual region (M1–6, lentiform, insula, and caudate), the automated method demonstrated acceptable performance. Conclusion The automated system we developed approached the stroke expert in performance when scoring ASPECTS on non-contrast computed tomography scans of acute ischemic stroke patients.

This paper reports the cost of endovascular materials used for the treatment of large-vessel ischemic stroke in the anterior circulation according to the angiographic score and clinical results at three months. From November 2009 to July 2011, 57 ischemic patients (mean age, 64.6 ±13.8 years) with anterior large vessel occlusion were included. Mean National Institutes of Health Stroke Scale (NIHSS) on admission was 18.4 ± 4.9. Mean duration of symptoms until the arterial puncture was 207±67 minutes. Recanalization was assessed using the Thrombolysis In Myocardial Infarction (TIMI) score. Patient selection was performed on a non-enhanced CT scanner. According to the TIMI final angiographic score and the modified Rankin score (mRS) at three months, we determined the cost of the material used. Complete (n=12, TIMI grade 3) or partial perfusion (n=35, TIMI grade 2) was achieved in 47 (82.5%) lesions. At three months, 33.3% (n=19) had a mRS score ≤ 2. The mean cost of the material used in the operative room was 5018±2402 euro. Intra-arterial thrombolysis presents a substantial initial cost and the long-term economic impact has to be evaluated. Our health system has to take the price of these new technologies into account for future medical choices and urgently evaluate them in randomized controlled trials.

Introduction: There is interest in understanding thrombus dynamics from IV TPA prior to endovascular thrombectomy (EVT) given the possible dichotomy amongst sites of occlusion for IV TPA benefit/harm. Kaesmacher et al reported beneficial 5+% rates of early TICI > 2a reperfusion in distal M1 or M2 MCA occlusions with IV TPA. However in more proximal occlusions this was rare; and potentially harmful worsening of perfusion seen with change of occlusion site. We aimed to examine IV TPA related thrombus dynamics including migration further across both proximal and distal occlusions in a multicenter prospective cohort study INTERRSeCT. Methods: Acute ischemic stroke patients with intracranial occlusion who had baseline CTA and follow-up CTA or initial run angio in INTERRSeCT and IV TPA were reviewed. We evaluated change of occlusion site (COS) and classified patients into 4 categories: Complete Recanalization (CR) of primary occlusive lesion with no remaining thrombus; definite Thrombus Migration (dTM) with primary occlusion site moved to a distal artery and occlusion site patent on baseline CTA; probable Thrombus Migration (pTM) with COS evident but initial occlusion extent not visualized; or No Change of occlusion site (NC). Results: A total of 462 IV TPA patients were enrolled, 41% received EVT. Median time from TPA to follow-up imaging was 133 minutes. COS was seen in 50% of cases with CR in 15% and TM in 35% (dTM 12%, pTM 23%). Distal artery occlusion and longer interval of TPA to imaging were independent predictors for COS. In 62 proximal occlusion (ICA and proximal-mid M1 MCA) patients with follow-up imaging within 60 mins after TPA (receiving EVT in 94%), any TM showed a lower rate of 90-day mRS≤2 than NC (47% vs 78%, adjusted OR 0.21, 95%CI 0.04-0.87). No CR was seen in this early group. Conclusions: Thrombus migration is common after IV TPA. Thrombus instability from IV TPA may worsen clinical outcome in proximal occlusions despite early EVT initiation, possibly due to migration of thrombus to distal arteries accelerating infarction or more challenging thrombectomy due to thrombus dispersion. The benefit of IV TPA prior to EVT at comprehensive stroke centers for ICA or prox-mid M1 occlusions require more study in randomized clinical trials.

Introduction: Multiple studies have correlated larger final infarct volume (FIV) with worse clinical outcomes. In INTERRSeCT , an international multicenter prospective cohort study, we sought to determine the favorable intracranial clot characteristics predicting smaller infarct volumes. Methods: FIV was measured (24 ±12 hours after baseline imaging) in 605 patients from INTERRSeCT study by blinded readers using Quantomo (Cybertrial Inc, Calgary). Clot Burden Score (CBS) is a 10-point scale with 10 referring to a completely patent ipsilateral anterior circulation from ICA to both M2 arteries, whereas 0 refers to a completely occluded ipsilateral anterior circulation. Residual Flow Grade (RFG) assesses the radiological permeability of the clot to contrast, with grade 0, 1, and 2 defined as no contrast, diffuse ghosting, and hairline lumen, respectively. Both of these scores were assessed by a blinded reader to the FIV. Using ordinal logistic regression, FIV was divided into deciles as the outcome. CBS and RFG were analyzed from 0 to 10, and 0 to 2, respectively. Two models were used, the first has no recanalization status, while the second included it. Results: The median FIVs with and without recanalization were 12.34 ml (IQR: 32.3 ml) and 22.15 ml (IQR: 60.12ml), respectively. CBS and RFG were independently predictive of FIV (p-value= <0.001 and 0.003, respectively). The common ORs for having one decile higher FIV for 1 point increase in CBS and RFG were 0.82 (CI: 0.77, 0.87) and 0.66 (CI: 0.51, 0.86), respectively. After adjusting for recanalization, the common ORs for having one decile higher FIV for 1 point increase in CBS and RFG were 0.83 (CI: 0.78, 0.88) and 0.72 (CI: 0.54, 0.94), respectively. Conclusions: Residual flow grade and clot burden score are fast and practical techniques for practitioners treating acute ischemic stroke patients. Favorable RFG and CBS independently, predict lower infarct volumes regardless of whether recanalization achieved.