The benefits of endovascular revascularization using the contact aspiration technique vs the stent retriever technique in patients with acute ischemic stroke remain uncertain because of lack of ...evidence from randomized trials.
To compare efficacy and adverse events using the contact aspiration technique vs the standard stent retriever technique as a first-line endovascular treatment for successful revascularization among patients with acute ischemic stroke and large vessel occlusion.
The Contact Aspiration vs Stent Retriever for Successful Revascularization (ASTER) study was a randomized, open-label, blinded end-point clinical trial conducted in 8 comprehensive stroke centers in France (October 2015-October 2016). Patients who presented with acute ischemic stroke and a large vessel occlusion in the anterior circulation within 6 hours of symptom onset were included.
Patients were randomly assigned to first-line contact aspiration (n = 192) or first-line stent retriever (n = 189) immediately prior to mechanical thrombectomy.
The primary outcome was the proportion of patients with successful revascularization defined as a modified Thrombolysis in Cerebral Infarction score of 2b or 3 at the end of all endovascular procedures. Secondary outcomes included degree of disability assessed by overall distribution of the modified Rankin Scale (mRS) score at 90 days, change in National Institutes of Health Stroke Scale (NIHSS) score at 24 hours, all-cause mortality at 90 days, and procedure-related serious adverse events.
Among 381 patients randomized (mean age, 69.9 years; 174 women 45.7%), 363 (95.3%) completed the trial. Median time from symptom onset to arterial puncture was 227 minutes (interquartile range, 180-280 minutes). For the primary outcome, the proportion of patients with successful revascularization was 85.4% (n = 164) in the contact aspiration group vs 83.1% (n = 157) in the stent retriever group (odds ratio, 1.20 95% CI, 0.68-2.10; P = .53; difference, 2.4% 95% CI, -5.4% to 9.7%). For the clinical efficacy outcomes (change in NIHSS score at 24 hours, mRS score at 90 days) and adverse events, there were no significant differences between groups.
Among patients with ischemic stroke in the anterior circulation undergoing thrombectomy, first-line thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful revascularization rate at the end of the procedure.
clinicaltrials.gov Identifier: NCT02523261.
Middle cerebral artery M2-segment occlusions represent an important subgroup of patients with acute stroke with large-vessel occlusion. The safety of mechanical thrombectomy, especially contact ...aspiration (CA), in such distal intracranial occlusions is still under debate. We compared reperfusion, adverse events, neurological recovery, and functional outcome of patients with isolated M2 occlusions according to the first-line strategy mechanical thrombectomy devices (CA versus stent retriever SR).
This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was successful reperfusion at the end of all endovascular procedures, defined as modified Thrombolysis in Cerebral Infarction (mTICI) scores 2b/3. Secondary outcomes were mTICI 2c/3 and mTICI 3, 90-day functional outcome, assessed with the modified Rankin Scale score. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage.
Seventy-nine patients were included: 48 were allocated to the CA group and 31 to the SR group. There were no significant differences between CA and SR groups in reperfusion after all endovascular procedures regarding mTICI 2b/3 (89.6% versus 83.9%;
=0.36), mTICI 2c/3 (54.2% versus 54.8%;
=0.90), and mTICI 3 (35.4% versus 41.9%;
=0.36) rates. There were no significant differences between CA and SR groups in 90-day modified Rankin Scale ≤2 rate (54.4% versus 50.0%;
=0.84), 24-hour change in National Institutes of Health Stroke Scale (mean difference, -3.9; 95% confidence interval, -7.9 to 0.01), and Alberta Stroke Program Early Computed Tomography score (mean difference, 0.9; 95% confidence interval, -0.1 to 2.0) scores. Safety parameters were well balanced between the 2 groups except for a higher 90-day mortality rate in the CA group (19.6% versus 3.3%;
=0.078).
First-line mechanical thrombectomy with CA compared with SR did not result in an increased successful revascularization rate in patients with acute stroke with isolated M2 occlusion.
The relationship between stroke topography (ie, the regions damaged by the infarct) and functional outcome can aid clinicians in their decision-making at the acute and later stages. However, the side ...(left or right) of the stroke may also influence the identification of clinically relevant regions. We sought to determine which brain regions are associated with good functional outcome at 3 months in patients with left-sided and right-sided stroke treated by endovascular treatment using the diffusion-weighted imaging-Alberta Stroke Program Early CT Score (DWI-ASPECTS).
Patients with ischaemic stroke (n = 405) were included from the ASTER trial and Pitié-Salpêtrière registry. Blinded readers rated ASPECTS on day 1 DWI. Stepwise logistic regression analyses were performed to identify the regions related to 3-month outcome in left (n = 190) and right (n = 215) sided strokes with the modified Rankin scale (0-2) as a binary independent variable and with the 10 regions-of-interest of the DWI-ASPECTS as independent variables.
Median National Institute of Health Stroke Scale (NIHSS) at baseline was 17 (IQR: 12-20), median age was 70 years (IQR: 58-80) and median day-one NIHSS 9 (IQR: 4-18). Not all brain regions have the same weight in predicting good outcome at 3 months; moreover, these regions depend on the affected hemisphere. In left-sided strokes, the multivariate analysis revealed that preservation of the caudate nucleus, the internal capsule and the cortical M5 region were independent predictors of good outcome. In right-sided strokes, the cortical M3 and M6 regions were found to be clinically relevant.
Cortical non-motors areas related to outcome differed between left-sided and right-sided strokes. This difference might reflect the specialisation of the dominant and non-dominant hemispheres for language and attention, respectively. These results may influence decision-making at the acute and later stages.
NCT02523261.
The clot burden score (CBS) at admission reliably evaluates the thrombus burden in acute ischemic stroke patients with anterior circulation large vessel occlusion. Mechanical thrombectomy has been ...diversified, especially with contact aspiration technique, and its efficiency with respect to the thrombus burden is not known. We compared reperfusion, adverse events, neurological recovery, and 90-day functional outcome of stent retriever use versus contact aspiration according to the admission CBS.
This is a post hoc analysis of the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) randomized trial. The primary outcome was successful reperfusion after all procedures, defined as modified Thrombolysis in Cerebral Infarction scores 2b/3. Secondary outcomes were 90-day functional outcome, assessed with the modified Rankin Scale. Safety outcomes included 90-day mortality and any intracerebral hemorrhage.
A total of 231 randomized patients were included in this study: 114 patients had a CBS of 0 to 6 and 117 a CBS ≥7 at admission. Successful reperfusion at procedure end was achieved more frequently in patients with CBS ≥7 (88.9%) than patients with a CBS 0 to 6 (81.6%; fully adjusted risk ratio, 1.09; 95% confidence interval, 1.01-1.28). Favorable outcome (modified Rankin Scale score, 0-2) at 90 days was achieved in significantly more patients with CBS ≥7 (61.9%) than in patients with CBS 0 to 6 (41.8%; fully adjusted risk ratio, 1.19; 95% confidence interval, 1.02-1.40). No outcome differences of first-line mechanical thrombectomy strategy (aspiration versus stent) on any angiographic or clinical outcomes were observed between the 2 groups. We also found no evidence of interaction between first-line mechanical thrombectomy strategy and CBS groups regarding safety.
First-line mechanical thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful reperfusion rate in acute ischemic stroke patients with large vessel occlusion of the anterior circulation according to the admission CBS. The latter, however, seems to be a reliable prognostic indicator of angiographic and clinical outcome.
Elevated blood pressure (BP) is common among patients presenting with acute ischemic stroke due to large vessel occlusions. The literature is inconsistent regarding the association between admission ...BP and outcome of mechanical thrombectomy (MT). Moreover, it is unclear whether the first line thrombectomy strategy (stent retriever SR versus contact aspiration CA) modifies the relationship between BP and outcome.
This is a post hoc analysis of the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) randomized trial. BP was measured prior to randomization in all included patients. Co-primary outcomes included 90-day functional independence (modified Rankin Scale mRS 0-2) and successful revascularization (modified Treatment in Cerebral Ischemia mTICI 2b-3). Secondary outcomes included symptomatic intracerebral hemorrhage (sICH) and parenchymal hemorrhage (PH) within 24 hours.
A total of 381 patients were included in the present study. Mean (SD) systolic BP (SBP) and diastolic BP (DBP) were 148 (26) mm Hg and 81 (16) mm Hg, respectively. There was no association between SBP or DBP and successful revascularization or 90-day functional independence. Similarly, there was no association between admission SBP or DBP with sICH or PH. Subgroup analysis based on the first-line thrombectomy strategy revealed similar results with no heterogeneity across groups.
Admission BP was not associated with functional, angiographic or safety outcomes. Results were similar in both CA and CA groups.
In recent years, the production of 3D geospatial data using formats such as IFC, CityGML and GeoJSON, has increased. Visualizing this data on the web requires solving a variety of problems, such as ...the massive amount of 3D objects to be visualized at the same time and the creation of geometry suitable for a 3D viewer. Cesium and OGC introduced the 3D Tiles format in 2015 to solve these issues. They have created a specific format optimized for streaming and rendering 3D geospatial content, based on the glTF format developed by Khronos. The recency of the 3D Tiles format implies the need to experiment around this format and to test its interoperability with other geospatial and urban data formats. There is also the will to innovate on the organization of 3D objects in order to offer a better control on the visualization. Therefore, there is a need for an open source tool capable of converting 3D geospatial data into 3D Tiles to visualize them on the web, but also to test and develop new methods of spatial clustering and creating Levels of Detail (LoD) of urban objects. We propose Py3DTilers in this paper, an open source tool to convert and manipulate 3D Tiles from the most common 3D geospatial data models: CityGML, IFC, OBJ, and GeoJSON. With this tool, we ensure that the generated 3D Tiles respect the specification described by the OGC, in order to be used in various viewers. We provide a generic solution for spatially organizing objects and for creating LoDs, while allowing the community to customize these methods to go further in finding efficient solutions for visualizing geospatial objects on the web.
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