Krieg und Wiederaufbau im Irak

Der Irakkrieg wurde militärisch wesentlich schneller entschieden als von vielen befürchtet. Die gesamtwirtschaftlichen Kosten des Krieges sind dennoch bedeutend. So ist die jährliche Belastung des US-Haushalts durch die Militärausgaben für den Irakkrieg - gemessen am Bruttoinlandsprodukt - vergleichbar mit der für den Vietnamkrieg. Es gibt aber auch indirekte Belastungen im Gefolge des Irakkonflikts, die mit der Unsicherheit von Investoren und Verbrauchern zu tun haben und die negativen Effekte des internationalen Terrorismus verstärken. Ein "Marshallplan" mit den vier Elementen Friedenssicherung, Entschuldung, Wiederaufbau und Selbstbestimmung könnte den Irak zu Stabilität und Wachstum führen und zugleich dem weltweiten Vertrauensschwund entgegenwirken.

Ongoing Geometric Remodeling of the Parent Artery After Flow-Diverter Stent Reconstruction in Cerebral Aneurysms: The Device Design Matters

Objective Configuration changes of the parent artery (PA) after flow-diverter (FD) stent reconstruction, caused by the bending force of the device, may have an additional role in aneurysm occlusion as a result of the secondary alteration of intra-aneurysmal hemodynamics related to the geometry alteration of the vessel. To determine the degree of PA deformation and aneurysm occlusion rates after deployment of 2 different types of FD. Methods Patients treated with 2 different designs of cobalt-chromium braid (48 and 64 wire braid) structure FD were subject to analysis. Vascular angle changes at the level of the reconstructed segment immediately after FD deployment and at 1 year follow-up were measured and the potential relationship with aneurysmal occlusion rate was analyzed. Results Forty-two patients harboring 48 aneurysms were included in the present study. The aneurysms were divided into side wall (85.4%) and bifurcation types (14.6%). Twenty-six aneurysms were treated using the Pipeline FD (48 wire braid; 54.2%) and 22 using the Evolve FD (64 wire braid; 45.8%). Of the 48 aneurysms, 42 (87.5%) met the primary end point of complete occlusion at 12 months. The median postdeployment angle change was 7.04°± 4.59° for the Pipeline and 5.05°± 2.49° for the Evolve, whereas the median 12 months follow-up angle change was 15.49°± 10.99° and 10.01°± 8.83°, respectively. PA angle changes were significantly higher in the bifurcation group compared with the side wall group both during procedure and at 12 months follow-up. Angle change had a statistically nonsignificant association with complete aneurysm occlusion. Conclusions PA deformation starts immediately after deployment and remodeling continues for 1 year after. Aneurysms located in the vessel bifurcation were more prone to PA straightening after FD deployment than were side wall aneurysms. Furthermore, Pipeline seemed to be more prone to inducing vascular deformation, compared with Evolve

Single antiplatelet regimen in flow diverter treatment of cerebral aneurysms: The drug matters. A systematic review and meta-analysis

BACKGROUND Hemorrhagic and thromboembolic complications (TECs) are the main concerns in the endovascular treatment of intracranial aneurysms using flow diverter devices (FDs). The clinical demand for single antiplatelet therapy (SAPT) is increasing especially with the development of devices with lower thrombogenicity profile. However, the safety of SAPT is not well established. OBJECTIVE To analyze the safety and efficacy of SAPT in terms of ischemic and hemorrhagic complications in patients undergoing FDs treatment for cerebral aneurysms. METHODS A systematic literature search and meta-analysis were conducted in PubMed, Ovid MEDLINE, Ovid Embase, and Web of Science from January 2010 until October 2022. Twelve articles which reported SAPT and data on hemorrhagic, TECs, and mortality following FDs treatment were included. RESULTS Overall, the 12 studies involved 237 patients with 295 aneurysms. Five investigated the safety and efficacy of SAPT in 202 unruptured aneurysms. Six studies focused on 57 ruptured aneurysms. One study included both ruptured and unruptured aneurysms. Among the 237 patients, prasugrel was most often used as SAPT in 168 cases (70.9%), followed by aspirin in 42 (17.7%) patients, and by ticagrelor in 27 (11.4%). Overall, the hemorrhagic complication rate was 0.1% (95% CI 0% to 1.8%). The TEC rate was 7.6% (95% CI 1.7% to 16.1%). In the subgroup analysis, the TEC rates of prasugrel monotherapy of 2.4% (95% CI 0% to 9.3%) and ticagrelor monotherapy of 4.2% (95% CI 0.1% to 21.1%) were lower than of aspirin monotherapy 20.2% (95% CI 5.9% to 38.6%). The overall mortality rate was 1.3% (95% CI 0% to 6.1%). CONCLUSION According to the available data, SAPT regimen in patients undergoing FDs treatment for cerebral aneurysms has an acceptable safety profile, especially with the use of ADP-receptor antagonists

Optimal aus Fehlern lernen

Fundierte Fehleranalyse Die interventionelle Neuroradiologie ist eine dynamische Disziplin mit innovativen Lösungen und expandierenden Therapieansätzen. Fehler bei Neurointerventionen sind unvermeidbar und oft schwerwiegend – daher ist eine klare Fehlerdefinition wichtig, um Ursachen zu identifizieren und Massnahmen zu ergreifen

Flow-augmentation STA-MCA bypass for acute and subacute ischemic stroke due to internal carotid artery occlusion and the role of advanced neuroimaging with hemodynamic and flow-measurement in the decision-making: preliminary data

Symptomatic patients with ischemic stroke due to internal carotid artery (ICA) occlusion often present with compromised brain hemodynamic status involving substantially larger parts of the affected vascular territory than the ischemic core itself (1-3). Despite the fact that the “Extracranial-Intracranial” (EC-IC) Bypass Study Group and the “Carotid Occlusion Surgery Study” (COSS) failed to demonstrate a benefit of bypass in comparison to medical therapy (4,5), several studies showed a significant improvement in hemodynamic parameters after superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery was performed in carefully selected patients (6-9) and even a reduction in stroke recurrence (6). Analysis showed that the failure of the COSS trial (5) to show a benefit regarding ipsilateral 2-year stroke recurrence in patients undergoing cerebral bypass revascularization was likely caused by a failure of the semiquantitative, hemispheric oxygen extraction fraction (OEF) ratio method used in the trial than by the selection of the patients for bypass based on hemodynamic compromise (10). Therefore, alternative and especially quantitative imaging techniques are needed to assess hemodynamic status in patients with ischemic stroke due to ICA occlusion

A Novel Dual-Energy CT Method for Detection and Differentiation of Intracerebral Hemorrhage From Contrast Extravasation in Stroke Patients After Endovascular Thrombectomy : Feasibility and First Results

PURPOSE: Dual-energy computed tomography (DECT) has been shown to be able to differentiate between intracranial hemorrhage (ICH) and extravasation of iodinated contrast media (contrast staining [CS]). TwinSpiral DECT is a recently introduced technique, which allows image acquisition at two different energy levels in two consecutive spiral scans. The aim of this study was to evaluate the feasibility and accuracy of TwinSpiral DECT to distinguish between ICH and CS after endovascular thrombectomy (EVT) in patients with acute ischemic stroke. METHODS: This retrospective single-center study conducted between November 2019 and July 2020 included non-contrast TwinSpiral DECT scans (tube voltages 80 and 150Sn kVp) of 39 ischemic stroke patients (18 females, 21 males, mean age 69 ± 11 years) within 48-72 h after endovascular thrombectomy. Parenchymal hyperdensity was assessed for the presence of ICH or/and CS by two board certified and fellowship-trained, blinded and independent neuroradiologists using standard mixed images and virtual non-contrast (VNC) images with corresponding iodine maps from TwinSpiral DECT. Follow-up examinations (FU; CT or MRI) were used as a standard of reference. Sensitivity, specificity, and accuracy for the detection of ICH as well as the inter-reader agreement were calculated. RESULTS: Parenchymal hyperdensities were detected in 17/39 (44%) patients. Using DECT, they were classified by both readers as ICH in 9 (53%), CS in 8 (47%), and mixture of both in 6 (35%) cases with excellent agreement (κ = 0.81, P < 0.0001). The sensitivity, specificity, and accuracy for the detection of ICH in DECT was 90% (95% confidence interval [CI]: 84-96%), 100% (95% CI 94-100%) and 95% (95% CI 89-100%), and in mixed images 90% (95% CI 84-96%), 86% (95% CI 80-92%) and 88% (95% CI 82-94%), respectively. Inter-reader agreement for detecting ICH on DECT compared to the mixed images was κ = 1.00 (P < 0.0001) vs. κ = 0.51 (P = 0.034). CONCLUSION: TwinSpiral DECT demonstrates high accuracy and excellent specificity for differentiating ICH from CS in patients after mechanical thrombectomy due to acute ischemic stroke, and improves inter-reader agreement for detecting ICH compared to the standard mixed images

A Novel Dual-Energy CT Method for Detection and Differentiation of Intracerebral Hemorrhage From Contrast Extravasation in Stroke Patients After Endovascular Thrombectomy : Feasibility and First Results.

PURPOSE Dual-energy computed tomography (DECT) has been shown to be able to differentiate between intracranial hemorrhage (ICH) and extravasation of iodinated contrast media (contrast staining [CS]). TwinSpiral DECT is a recently introduced technique, which allows image acquisition at two different energy levels in two consecutive spiral scans. The aim of this study was to evaluate the feasibility and accuracy of TwinSpiral DECT to distinguish between ICH and CS after endovascular thrombectomy (EVT) in patients with acute ischemic stroke. METHODS This retrospective single-center study conducted between November 2019 and July 2020 included non-contrast TwinSpiral DECT scans (tube voltages 80 and 150Sn kVp) of 39 ischemic stroke patients (18 females, 21 males, mean age 69 ± 11 years) within 48-72 h after endovascular thrombectomy. Parenchymal hyperdensity was assessed for the presence of ICH or/and CS by two board certified and fellowship-trained, blinded and independent neuroradiologists using standard mixed images and virtual non-contrast (VNC) images with corresponding iodine maps from TwinSpiral DECT. Follow-up examinations (FU; CT or MRI) were used as a standard of reference. Sensitivity, specificity, and accuracy for the detection of ICH as well as the inter-reader agreement were calculated. RESULTS Parenchymal hyperdensities were detected in 17/39 (44%) patients. Using DECT, they were classified by both readers as ICH in 9 (53%), CS in 8 (47%), and mixture of both in 6 (35%) cases with excellent agreement (κ = 0.81, P < 0.0001). The sensitivity, specificity, and accuracy for the detection of ICH in DECT was 90% (95% confidence interval [CI]: 84-96%), 100% (95% CI 94-100%) and 95% (95% CI 89-100%), and in mixed images 90% (95% CI 84-96%), 86% (95% CI 80-92%) and 88% (95% CI 82-94%), respectively. Inter-reader agreement for detecting ICH on DECT compared to the mixed images was κ = 1.00 (P < 0.0001) vs. κ = 0.51 (P = 0.034). CONCLUSION TwinSpiral DECT demonstrates high accuracy and excellent specificity for differentiating ICH from CS in patients after mechanical thrombectomy due to acute ischemic stroke, and improves inter-reader agreement for detecting ICH compared to the standard mixed images

CT-Guided Interventions Using a Free-Hand, Optical Tracking System: Initial Clinical Experience

Purpose: The present study was designed to evaluate the geometrical accuracy and clinical applicability of a new, free-hand, CT-guided, optical navigation system. Methods: Fifteen procedures in 14 consecutive patients were retrospectively analyzed. The navigation system was applied for interventional procedures on small target lesions, in cases with long needle paths, narrow access windows, or when an out-of-plane access was expected. Mean lesion volume was 27.9ml, and mean distance to target measured was 107.5mm. Eleven of 15 needle trajectories were planned as out-of-plane approaches regarding the axial CT plane. Results: Ninety-one percent of the biopsies were diagnostic. All therapeutic interventions were technically successful. Targeting precision was high with a mean distance of the needle tip from planned target of 1.98mm. Mean intervention time was 1:12h. A statistically significant correlation between angular needle deviation and intervention time (p=0.007), respiratory movement of the target (p=0.008), and body mass index (p=0.02) was detected. None of the evaluated parameters correlated significantly with the distance from the needle tip to the planned target. Conclusions: The application of a navigation system for complex CT-guided procedures provided safe and effective targeting within a reasonable intervention time in our serie

Ultra-High-Resolution Time-of-Flight MR-Angiography for the Noninvasive Assessment of Intracranial Aneurysms, Alternative to Preinterventional DSA?

Purpose The 3D time-of-flight (TOF) magnetic resonance angiography (MRA) at 3T shows high sensitivity for intracranial aneurysms but is inferior to three-dimensional digital subtraction angiography (3D-DSA) regarding aneurysm characteristics. We applied an ultra-high-resolution (UHR) TOF-MRA using compressed sensing reconstruction to investigate the diagnostic performance in preinterventional evaluation of intracranial aneurysms compared to conventional TOF-MRA and 3D-DSA. Methods In this study 17 patients with unruptured intracranial aneurysms were included. Aneurysm dimensions, configuration, image quality and sizing of endovascular devices were compared between conventional TOF-MRA at 3T and UHR-TOF with 3D-DSA as gold standard. Quantitatively, contrast-to-noise ratios (CNR) were compared between TOF-MRAs. Results On 3D-DSA, 25 aneurysms in 17 patients were detected. On conventional TOF, 23 aneurysms were detected (sensitivity: 92.6%). On UHR-TOF, 25 aneurysms were detected (sensitivity: 100%). Image quality was not significantly different between TOF and UHR-TOF (p = 0.17). Aneurysm dimension measurements were significantly different between conventional TOF (3.89 mm) and 3D-DSA (4.2 mm, p = 0.08) but not between UHR-TOF (4.12 mm) and 3D-DSA (p = 0.19). Irregularities and small vessels at the aneurysm neck were more frequently correctly depicted on UHR-TOF compared to conventional TOF. Comparison of the planned framing coil diameter and flow-diverter (FD) diameter revealed neither a statistically significant difference between TOF and 3D-DSA (coil p = 0.19, FD p = 0.45) nor between UHR-TOF and 3D-DSA (coil: p = 0.53, FD 0.33). The CNR was significantly higher in conventional TOF (p = 0.009). Conclusion In this pilot study, ultra-high-resolution TOF-MRA visualized all aneurysms and accurately depicted aneurysm irregularities and vessels at the base of the aneurysm comparably to DSA, outperforming conventional TOF. UHR-TOF with compressed sensing reconstruction seems to represent a non-invasive alternative to pre-interventional DSA for intracranial aneurysms