1,720,967 research outputs found
Usefulness of Thromboelastography in the Detection and Management of Tissue Plasminogen Activator-Associated Hyperfibrinolysis
No full textRotation thromboelastometry is a viscoelastometric method that provides a rapid assessment of a patient's hemostatic processes in emergency settings, allowing prompt identification of specific coagulation abnormalities. Its results thus might guide targeted replacement therapy in hemorrhagic conditions, in case of platelet or coagulation factor deficiency, or hyperfibrinolysis, which is difficult to identify otherwise. Although currently used in emergency and traumatic surgery, there are limited data about thromboelastometry in ischemic stroke, particularly in monitoring the coagulative response to recombinant tissue plasminogen activator after intravenous thrombolysis (IVT). Here we report a case of ischemic stroke complicated by a remote asymptomatic intracranial hemorrhage after IVT and additional endovascular therapy that has been successfully treated with intravenous infusion of tranexamic acid after the detection of the status of hyperfibrinolysis provided by thromboelastometry. Further studies are needed to provide the potential usefulness of thromboelastometry and tranexamic acid in ischemic stroke complicated by intracranial bleeding
Qualitative versus automatic evaluation of CT perfusion parameters in acute posterior circulation ischaemic stroke
Get PDFPurpose To compare the diagnostic accuracy (ACC) in the detection of acute posterior circulation strokes between qualitative evaluation of software-generated colour maps and automatic assessment of CT perfusion (CTP) parameters.
Methods Were retrospectively collected 50 patients suspected of acute posterior circulation stroke who underwent to CTP (GE “Lightspeed”, 64 slices) within 24 h after symptom onset between January 2016 and December 2018. The Posterior circulation-Acute Stroke Prognosis Early CT Score (pc-ASPECTS) was used for quantifying the extent of ischaemic areas on non-contrast (NC)CT and colour-coded maps generated by CTP4 (GE) and RAPID (iSchemia View) software. Final pc-ASPECTS was calculated on follow-up NCCT and/or MRI (Philips Intera 3.0 T or Philips Achieva Ingenia 1.5 T). RAPID software also elaborated automatic quantitative mismatch maps.
Results By qualitative evaluation of colour-coded maps, MTT-CTP4D and Tmax-RAPID showed the highest sensitivity (SE) (88.6% and 90.9%, respectively) and ACC (84% and 88%, respectively) compared with the other perfusion parameters (CBV, CBF). Baseline NCCT and CBF provided by RAPID quantitative perfusion mismatchmaps had the lowest SE (29.6%and 6.8%, respectively) and ACC (38% and 18%, respectively). CBF and Tmax assessment provided by quantitative RAPID perfusion mismatch maps showed significant lower SE and ACC than qualitative evaluation. No significant differences were found between the pc-ASPECTSs assessed on colour-coded MTT and Tmax maps neither between the scores assessed on colourcoded CBV-CTP4D and CBF-RAPID maps.
Conclusion Qualitative analysis of colour-codedmaps resultedmore sensitive and accurate in the detection of ischaemic changes than automatic quantitative analysis
“Opening the Unopenable”: Endovascular Treatment in a Patient with Three Months' Internal Carotid Artery Occlusion and Hemispheric Symptomatic Hypoperfusion
No full textBackground Internal carotid artery occlusion (ICAO) is defined as “untouchable” by all specialists; no treatment is indicated because intervention risks (carotid endarterectomy (CEA) or endovascular treatment) are usually much more than benefits. We report the case of a patient admitted to our hospital with an atherothrombotic ischemic stroke due to symptomatic acute ICAO, who developed a recurrent stroke with hemispheric hypoperfusion and was treated in the emergency department with ICAO revascularization after 60 days of occlusion finding. Case Description D.G., a 62-year-old man, came to our attention for a transient episode of left weakness and hypoesthesia. The electrocardiogram revealed a new diagnosis of atrial fibrillation. CT angiography showed right ICAO; computed tomography and magnetic resonance imaging studies with perfusion imaging revealed a severe hemispheric hypoperfusion. Full anticoagulation therapy was started, and antihypertensive therapy was reduced to help collateral circulation. Some weeks later, the patient was readmitted to the stroke unit for 2 episodes of left-hand weakness. Cerebral angiography confirmed right ICAO from the proximal tract to the siphon. After some days, the patient suffered a femoral hemorrhagic lesion, with active bleeding, and was treated with surgical intervention. On the following day, the patient presented with left hemiplegia with hemianesthesia (National Institutes of Health Stroke Scale score = 14). The patient was treated in the emergency department with a complex endovascular treatment with complete recanalization of ICAO by positioning 3 stents through the intravenous infusion of abciximab. After intensive rehabilitation, at the 3- and 6-month follow-up evaluations, the patient regained autonomy. Conclusion In literature, treatment of chronic ICAO is not indicated. Endovascular recanalization may be beneficial to patients with chronic cerebral hypoperfusion due to ICAO, when all conservative medical therapies have failed
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
OSAin ICH patients: prevalence and impact on outcome
Get PDFIn questo studio è con un grande campione di pazienti con emorragia cerebrale (111 soggetti) in cui è stata verificata una aumentata prevalenza di sospetto disturbo respiratorio del sonno valutat tramite la scala Berlin Questionnaire rispetto ad altrettanti con ischemia cerebrale (111 soggetti) e altrettanti controlli (n111). La metodica di appaiamento per variabili quali età, sesso, BMI e CCI ha permesso di escludere una eventuale influenza da parte di queste variabili. Dallo studio di variabili di outcome funzionale è risultata significativa la correlazione tra positività per disturbo respiratorio del sonno e un peggior outcome funzionale sia in termini di disabilità (mRS ≥ 3) che di mortalità (mRS =6) nei pazienti con BQ positivo, sia ischemici che emorragici. A riprova di questo ruolo prognosticamente negativo della sospetta OSAS nei pazienti con emorragia cerebrale anche un aumento della durata globale del ricovero in giorni dei pazienti nel gruppo dei positivi.
Nel tentativo di esplorare il legame tra disturbi respiratori del sonno ed emorragia cerebrale sono state valutate le neuroimmagini e le caratteristiche di ipertensione arteriosa. E’ stato così riscontrato un tasso complessivo di peggioramento delle lesioni al controllo a 10 giorni circa, aumentato significativamente nei pazienti BQ positivi, con associata inoltre una tendenza all’aumento dell’edema perilesionale.
L’ipotesi più probabile rimane comunque che il meccanismo principale con cui il disturbo respiratorio del sonno influisce sull’insorgenza e il peggioramento dell’emorragia cerebrale sia legato all’ipertensione arteriosa. Tale legame, facilmente intuibile considerate le discrete conoscenze sui tre fenomeni, è stato qui dimostrato tramite il riscontro di un tasso notevolmente e significativamente aumentato di ipertensione arteriosa, di profilo pressorio notturno alterato con prevalenza di pazienti non dipper e di aumentata pressione arteriosa farmaco resistente nei pazienti emorragici BQ positivi.Background: Obstructive sleep apnea (OSA) is currently undertaken to impair ischemic stroke risk especially by intracranial pressure, blood flow, glucose metabolism, atherogenesis, blood coagulation, cardiac arrhythmia and arterial hypertension. In OSA patients hypertension is often related to drug resistance and modification in nocturnal blood pressure profile. In stroke patients with OSA has been observed an impairment of functional outcome.
About OSA and intra cranial haemorrhage (ICH) few data are available in literature and most of them are anecdotal. We can speculate that OSA can affect on ICH by arterial hypertension.
Methods: in this study we sought to test whether suspected OSA is more prevalent in ICH group than in control. In order to limit potential confounding variables associated with acute ICH, we tested by Berlin Questionnaire (BQ) and Epworth Sleepiness Scale (ESS) referring to the previous 3 months before ICH. Secondarily, we tried to assess if OSA in ICH could affect on functional outcome (mRS) like disability or mortality, as described in ischemic stroke.
For these purposes we recruited 111 ICH patients matched by sex, age, Body Mass Index (BMI) and Charlson Comorbidity Index (CCI) with 111 ischemic stroke patients and 111 controls.
Results: In ICH patients we found BQ positivity in 30,6% vs 25,2% in ischemic stroke patients vs 13,5% in controls (p 0.01). Moreover BQ positive ICH patients had more disability, mortality, length of recovery, arterial hypertension, drug resistance hypertension and nocturnal blood pressure profile alteration, especially non dipper pattern, than BQ negative ICH.
Conclusion: The results suggest that OSA can be considered a risk factor and a negative prognostic factor in ICH patients, as described before in ischemic stroke patients. Moreover we can considered this fenomena probably related to blood pressure alteration caused by sleep breathing disorder
Cognitive performance following carotid endarterectomy or stenting in asymptomatic patients with severe ICA stenosis
Get PDFBackground. Endarterectomy (CEA) or stenting (CAS) of a stenotic carotid artery is currently undertaken to reduce stroke risk. In addition removal of the arterial narrowing has been hypothesized to improve cerebral hemodynamics and provide benefits in cognitive functions, by supposedly resolving a "hypoperfusion" condition. Methods. In this study we sought to test whether resolution of a carotid stenosis is followed by measurable changes in cognitive functions in 22 subjects with "asymptomatic" stenosis. Results. A main finding of the study was the statistically significant pre-post difference observed in the performance of phonological verbal fluency and Rey's 15-word immediate recall. Remarkably, there was a significant interaction between phonological verbal fluency performance and side of the carotid intervention, as the improvement in the verbal performance, a typical "lateralized" skill, was associated with resolution of the left carotid stenosis. Conclusion. The results reflect a substantial equivalence of the overall performance at the before- and after- CEA or CAS tests. In two domains, however, the postintervention performance resulted improved. The findings support the hypothesis that recanalization of a stenotic carotid could improve brain functions by resolving hypothetical "hypoperfusion" states, associated with the narrowing of the vessels. © 2013 Livio Picchetto et al
Olfactory function and viral recovery in COVID‐19
Get PDFOlfactory and taste disorders were reported in up to 30%-80% of COVID-19 patients. The purpose of our study was to objectively assess smell impairment in COVID-19 patients and to correlate olfactory function with viral recovery
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