The Netherlands Organisation for Health Research and Development, Sanquin Blood Supply, Chest Heart and Stroke Scotland, French Ministry of Health.

No abstract

Medtronic.

Campbell, B. C.V. et al. (2019) Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data.ABSTRACT Background: CT-perfusion (CTP) and MRI may assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of ischaemic core and penumbra volumes were associated with functional outcomes and treatment effect.

In adult Marfan patients, losartan treatment reduces aortic root dilatation rate. After aortic root replacement, losartan treatment reduces dilatation rate of the aortic arch.

Summary We use a coupled surface wave version of the Born approximation to compute the3‐D sensitivity kernel KT(r) of a seismic body wave traveltime T measured by cross‐correlation of a broad‐band waveform with a spherical earth synthetic seismogram. The geometry of a teleseismic S wave kernel is, at first sight, extremely paradoxical: the sensitivity is zero everywhere along the geometrical ray! The shape of the kernel resembles that of a hollow banana; in a cross‐section perpendicular to the ray, the shape resembles a doughnut. The cross‐path extent of such a banana–doughnut kernel depends upon the frequency content of the wave. The kernel for a very high‐frequency wave is a very skinny hollow banana; wave‐speed heterogeneity wider than this banana affects the traveltime, in accordance with ray theory. We also use the Born approximation to compute the sensitivity kernel KΔT(r) of a differential traveltime ΔT measured by cross‐correlation of two phases, such as SS and S, at the same receiver. The geometries of both an absolute SS wave kernel and a differential SS–S kernel are extremely complicated, particularly in the vicinity of the surface reflection point and the source‐to‐receiver and receiver‐to‐source caustics, because of the minimax character of the SS wave. Heterogeneity in the vicinity of the source and receiver exerts a negligible influence upon an SS–S differential traveltime ΔT only if it is smooth.

Background and Purpose— Recent randomized trials have proven the benefit of intra-arterial treatment (IAT) with retrievable stents in acute ischemic stroke. Patients with poor or absent collaterals (preexistent anastomoses to maintain blood flow in case of a primary vessel occlusion) may gain less clinical benefit from IAT. In this post hoc analysis, we aimed to assess whether the effect of IAT was modified by collateral status on baseline computed tomographic angiography in the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN). Methods— MR CLEAN was a multicenter, randomized trial of IAT versus no IAT. Primary outcome was the modified Rankin Scale at 90 days. The primary effect parameter was the adjusted common odds ratio for a shift in direction of a better outcome on the modified Rankin Scale. Collaterals were graded from 0 (absent) to 3 (good). We used multivariable ordinal logistic regression analysis with interaction terms to estimate treatment effect modification by collateral status. Results— We found a significant modification of treatment effect by collaterals ( P =0.038). The strongest benefit (adjusted common odds ratio 3.2 [95% confidence intervals 1.7–6.2]) was found in patients with good collaterals (grade 3). The adjusted common odds ratio was 1.6 [95% confidence intervals 1.0–2.7] for moderate collaterals (grade 2), 1.2 [95% confidence intervals 0.7–2.3] for poor collaterals (grade 1), and 1.0 [95% confidence intervals 0.1–8.7] for patients with absent collaterals (grade 0). Conclusions— In MR CLEAN, baseline computed tomographic angiography collateral status modified the treatment effect. The benefit of IAT was greatest in patients with good collaterals on baseline computed tomographic angiography. Treatment benefit appeared less and may be absent in patients with absent or poor collaterals. Clinical Trial Registration— URL: http://www.trialregister.nl and http://www.controlled-trials.com . Unique identifier: (NTR)1804 and ISRCTN10888758, respectively.

The effects of resolution and segmentation on the accuracy and precision of the WSS algorithm were quantified. We were able to calculate volumetric WSS in the carotid bifurcation and the aorta.