Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Mechanical thrombectomy beyond the circle of Willis: efficacy and safety of different techniques for M2 occlusions

BACKGROUND: M2 segment occlusions represent approximately one-third of non-lacunar ischemic stroke and can lead to permanent neurological deficits. Various techniques are available for mechanical thrombectomy beyond the circle of Willis, but data evaluating their effectiveness and safety are lacking. METHODS: A retrospective review of patients with ischemic stroke undergoing mechanical thrombectomy for M2 occlusions from 13 centers in North American and Europe was performed. Tandem or multiple-territory occlusions were excluded. The primary outcome was 90-day modified Rankin Scale and reperfusion rates across stent-retriever, direct aspiration and combined techniques. RESULTS: There were 465 patients (mean age 71.48+/-14.03 years, 53.1% female) with M2 occlusions who underwent mechanical thrombectomy. Stent-retriever alone was used in 133 (28.6%), direct aspiration alone in 93 (20.0%) and the combined technique in 239 (51.4%) patients. Successful reperfusion was achieved with the combined technique in 198 (82.2%; OR 2.6 (1.1-6.9)), with stent-retriever alone in 112 (84.2%; OR 9.2 (1.9-44.6)) and with direct aspiration alone in 62 (66.7%; referencecategory). Intraprocedural subarachnoid hemorrhages (iSAH) were 36 (7.7%) and were more likely to occur in patients treated with the stent-retrievers (OR 5.0 (1.1-24.3)) and combined technique (OR 4.6 (1.1-20.9)). Good clinical outcome was achieved in 260 (61.8%) patients, while 59 (14.0%) patients died. Older age, higher baseline NIHSS (National Institutes of Health Stroke Scale), parenchymal hemorrhage and iSAH were associated with poor outcome while successful recanalization and higher baseline ASPECTS (Alberta Stroke Program Early CT Score) were associated with good outcome. No differences were found among the three techniques in terms of clinical outcome. CONCLUSION: Stent-retrievers and a combined approach for M2 occlusions seem more effective than direct aspiration, but with higher rates of iSAH. This leads to no detectable difference in clinical outcome at 3 months

A revised stent-retriever anchor technique to obtain the distal access through a large or giant aneurysm

Endovascular treatment of brain aneurysms with flow diverter device can be technically difficult. Obtaining distal access through the wide neck of a large or giant aneurysm may be challenging and sometimes the microcatheter needs to be looped inside the aneurysm. However, the inability to resolve this loop and to straighten the microcatheter can preclude flow diverter placement. This brief report presents four cases of large/giant aneurysms treated with flow diverter device, in which our innovative stent-retriever anchor technique was used to obtain the distal access of the parent artery. All procedures were technically successful, and no complications were recorded

Are Early Seizures Predictive of Epilepsy after a Stroke? Results of a Population-Based Study

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; In addition to determining the cumulative incidence and risk factors for early seizures (ES), late seizures (LS) and post stroke epilepsy (PSE), we aimed at checking if ES represented a risk factor for epilepsy and if early treatment after ES prevented the occurrence of subsequent seizures. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; This study was part of a 2-year prospective community-based registry of all cerebrovascular events in the district of Udine (153,312 inhabitants), North-Eastern Italy, between April 1, 2007 and March 31, 2009. People with transient ischemic attacks (TIAs) were excluded from this study. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; In all, 782 cases of stroke (79.28% ischemic, 14.83% hemorrhagic, 3.20% subarachnoid hemorrhage and 2.69% undetermined) were identified. The incidence of ES, LS and PSE was 5.10, 3.14 and 2.22%, respectively. Intracerebral hemorrhage, subarachnoid hemorrhage, stroke of undetermined origin and hyponatremia, represented risk factors for ES (p &lt; 0.05). Among ischemic strokes, ES risk factors were hyponatremia (p = 0.024) and hemorrhagic transformation (p = 0.046). LS risk factors were younger age (p = 0.004) and cortical location of stroke (p = 0.004). Within ischemic strokes, LS risk factors were younger age (p = 0.020) and cortical location (p &lt; 0.0001). Within intracerebral hemorrhages, the only risk factor for LS was the presence of a previous ES (p = 0.017). PSE risk factors were the same as for LS. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; All acute conditions related to the occurrence of stroke are implicated in the pathogenesis of ES, which becomes a risk factor for LS only in the setting of intracerebral hemorrhages. Therefore, early antiepileptic treatment is needed only in this situation.</jats:p

Spinal cord ultrasonography of the newborn

Ultrasound represents the first-line survey for the assessment of spinal cord development abnormalities. In fact, within 6 months of life, the non-ossification of neuronal arcs provides an excellent acoustic window that allows a detailed depiction of the spinal canal, its content and of the surrounding soft tissues. Nevertheless, an accurate ultrasound examination requires a complete knowledge of the anatomy, the condition of normality, the frequent anatomical variants and the main pathologies involved. This review is intended to briefly summarize the US technique, the main clinical indication and the key notions that could help to properly perform this type of ultrasound examination

Correlation between Thrombus Perviousness and Distal Embolization during Mechanical Thrombectomy in Acute Stroke

Purpose: Thrombus permeability has been related to clot composition and treatment outcomes in stroke patients undergoing reperfusion therapies. The aim of this study was to evaluate whether thrombus perviousness, evaluated by multiphase computed tomography angiography (mCTA), is associated with distal embolization risk. Methods: We interrogated our dataset of acute ischemic stroke (AIS) patients involving the M1 segment of the middle cerebral artery (MCA) who had undergone mechanical thrombectomy, and we calculated thrombus average attenuation measurement (dHU) on non-contrast CT (NCCT) and clot perviousness on mCTA. dHU was calculated as the difference between the thrombus HU average value (tHU) and the HU average value on the contralateral side (cHU), while perviousness was calculated as the difference in mean clot density on mCTA and NCCT both in arterial (Perviousness pre-post-1) and delayed (Perviousness pre-post 2) phases. Results: A total of 100 patients (53 females (53%), mean age 72.74 [± 2.31]) with M1 occlusion were available for analysis. Perviousness, calculated between baseline and arterial phase of mCTA (Perviousness pre-post1), was lower in patients with distal embolization (p = 0.05), revealing an association between reduced perviousness and distal embolization risk. Logistic regression showed that thrombus perviousness calculated on the arterial phase of mCTA (OR, 0.66; 95% CI, 0.44–0.99] (p = 0.04)) and the contact aspiration technique (OR, 0.39; 95% CI, 0.15–1.02] (p = 0.05)) were protecting factors against distal embolization. Conclusion: Our study showed an association between reduced perviousness and distal embolization, suggesting that perviousness evaluation may be a useful neuroimaging biomarker in predicting distal embolization risk during mechanical thrombectomy

Hybrid treatment of large extracranial carotid artery aneurysm

An extracranial carotid artery aneurysm (ECAA) is a rare condition. The major complications are rupture and thromboembolism. Therefore, treatment is generally recommended. We report the case of a young woman affected by an ECAA, with a cervical pulsatile mass. A multidisciplinary evaluation was performed to ensure the best treatment in terms of safety and efficacy, and the patient underwent hybrid treatment. The 6-month computed tomography angiogram revealed patency of the carotid artery stents and the venous graft, in the absence of any relevant complications. An ECAA is a serious clinical condition. The treatment is challenging, and a multidisciplinary evaluation and precise planning are recommended

Stroke incidence and 30-day and six-month case fatality rates in Udine, Italy:a population-based prospective study

Background Stroke incidence in high-income countries is reported to decrease, and new data on stroke incidence and outcome are needed to design stroke services and to ameliorate stroke management. Methods This study is part of a two-year prospective community-based registry of all cerebrovascular events in the district of Udine (153 312 inhabitants), Friuli-Venezia Giulia region, northeast of Italy, between 1 April 2007 and 31 March 2009. Overlapping sources for case finding were used, combining hot and cold pursuit. Results We identified 784 stroke cases, 640 (81·6%) incident. The crude overall annual incidence rate per 100 000 residents was 256 (95% confidence interval 241–271) for all strokes and 209 (95% confidence interval 195–223) for first-ever strokes. Incidence rate for first-ever strokes was 181 (95% confidence interval 155–211) after adjustment to the 2007 Italian population and 104 (95% confidence interval 88–122) compared with the European standard population. Incidence rates for first-ever strokes was 215 (196–235) for women, 202 (183–223) for men. Crude annual incidence rates per 100 000 population were 167 (153–178) for ischemic stroke, 31 (26–37) for intracerebral hemorrhage, 8·1 (5·7–11·4) for sub-arachnoid hemorrage, and 4·6 (2·8–7·1) for undetermined stroke. Overall case fatality rates for first-ever stroke were 20·6% at 28 days and 30·2% at 180 days. Conclusions Our study shows incidence rates higher than previously reported in our region but not supporting the view of higher incidence rates in Northern than in Southern Italy. Results contribute to time-trends analysis on epidemiology, useful for dimensioning services in Italy and show the persistence of a gap between the outcome of stroke in Italy and that of the best performing European countries, urging to adopt better stroke management plans. </jats:sec

Hybrid treatment of large extracranial carotid artery aneurysm

An extracranial carotid artery aneurysm (ECAA) is a rare condition. The major complications are rupture and thrombo-embolism. Therefore, treatment is generally recommended. We report the case of a young woman affected by an ECAA, with a cervical pulsatile mass. A multidisciplinary evaluation was performed to ensure the best treatment in terms of safety and efficacy, and the patient underwent hybrid treatment. The 6-month computed tomography angiogram revealed patency of the carotid artery stents and the venous graft, in the absence of any relevant complications. An ECAA is a serious clinical condition. The treatment is challenging, and a multidisciplinary evaluation and precise planning are recommended