1,721,010 research outputs found
Pneumatosis intestinalis in oncologic patients: when should the radiologist not be afraid?
Full text linkPneumatosis intestinalis (PI) is a term used to describe the presence of submucosal and subserosal gas in the
gastrointestinal tract. It can occur as a primary disease or, more commonly, secondary to various other causes ranging
from benign conditions to fulminant diseases. We present four cases of benign PI in patients being treated for various
types of cancer. They had no abdominal symptoms, the physical examination was normal and PI was an isolated
incidental CT finding in the absence of other signs of bowel wall distress. A conservative non-surgical approach was
advocated and follow-up imaging documented the resolution of PI. The radiologist should recognize this condition in
order to help the oncologist to interpret its clinical significance and avoid unnecessary surgical procedures
La diagnosi precoce delle complicanze polmonari nel paziente onco-ematologico neutropenico febbrile in due passi
No full textObiettivi didattici:
Illustrare come ottimizzare il management del paziente ematologico neutropenico febbrile ad alto rischio di Infezioni Fungine
Invasive (IFI) mediante TC ad alta risoluzione (HRCT) del torace e angio-TC polmonare (CTPA).
Nel paziente neutropenico febbrile sono frequenti le complicanze polmonari infettive con prognosi severa, tra cui quelle ad
eziologia fungina, il cui outcome è strettamente legato alla tempestività della diagnosi.
L’imaging TC ha un ruolo fondamentale nel confermare il sospetto clinico e formulare un’ipotesi diagnostica .
Secondo i criteri EORCT, la diagnosi di IFI è possibile in presenza di un’ampia gamma di quadri HRCT (lesioni nodulari dense, con o senza halo sign, cavitazione o air-crescent sign) che entrano in diagnosi differenziale con altre condizioni infettive (batteri, virus, PJ, ecc...) e non infettive (localizzazione di malattia, BOOP, reazione a farmaci, ecc...).
In tale contesto, l'angiografia TC polmonare (CTPA) si è dimostrata utile nel restringere il ventaglio di possibili diagnosi differenziali in quanto aumenta la performance diagnostica della TC nella diagnosi precoce di IFI potendo documentare la presenza di angioinvasione.
Conclusioni: Nel paziente neutropenico febbrile, la HRCT a bassa dose eseguita precocemente è utile come screening (step1) per
individuare le complicanze polmonari da caratterizzare mediante CTPA (step2)
Beyond biomarkers: How enhanced CT imaging can improve the diagnostic-driven management of invasive mould disease
No full textCT imaging remains an essential diagnostic test for identification, staging and management of invasive mould infection (IMI) in patients with hematological malignancies. Yet the limited specificity of standard CT imaging can drive excessive antifungal use in patients, especially when more definitive diagnosis cannot be established through microbiology or invasive diagnostic procedures. CT pulmonary angiography (CTPA) is a complimentary, non-invasive approach to standard CT that allows for direct visualization of pulmonary arteries inside infiltrates for signs of angioinvasion, vessel destruction and vessel occlusion. Experience from several centers that are using CTPA as part of a standard diagnostic protocol for IMI suggests that a positive vessel occlusion sign (VOS) is the most sensitive and a specific sign of IMI in both neutropenic and non-neutropenic patients. CTPA is particularly useful in patients who develop suspected breakthrough IMI during antifungal prophylaxis because, unlike serum and/or BAL galactomannan and polymerase chain reaction (PCR) testing, the sensitivity is not reduced by antifungal therapy. A negative VOS may also largely rule-out the presence of IMI, supporting earlier discontinuation of empirical therapy. Future imaging protocols for IMI in patients with hematological malignancies will likely replace standard chest X-rays in favor of early low radiation dose CT exams for screening, with characterization of the lesions by CTPA and routine follow-up using functional/metabolic imaging such as 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (FDG-PET/CT) to assess treatment response. Hence, enhanced CT imaging techniques can improve the diagnostic-driven management of IMI management in high-risk patients with hematological malignancies
Segni radiologici di infezione fungina angioinvasiva: il vecchio e il nuovo
No full textPoster didattico.
Scopo: descrivere i principali segni radiologici suggestivi di infezione fungina angioinvasiva (IFI) in pazienti onco-ematologici
neutropenici febbrili.La TC è uno strumento importante nella diagnosi precoce di infezione polmonare fungina in pazienti
immunocompromessi.
Le infezioni fungine invasive (IFI) sono un'importante causa di morbidità e mortalità nei pazienti immunocompromessi con
grave neutropenia (da neoplasie ematologiche o aplasia midollare legata a trapianto di midollo osseo o chemioterapia). La
diagnosi precoce di IFI è fondamentale per poter istituire prontamente l’adeguata terapia antifungina in quanto la prognosi
dipende dalla tempestività del trattamento.
L’imaging radiologico di IFI si basa sul riscontro di segni apprezzabili alla TC ad alta risoluzione (HRCT) tra cui l'halo sign
(HS), l’air crescent sign (ACS), l’hypodense sign (HyS) ed il reversed halo sign (RHS). Recentemente è stato descritto un
ulteriore segno, il vessel occlusion sign (VOS), apprezzabile mediante angio-TC polmonare (CTPA). La stessa metodica
contrastografica consente inoltre di migliorare l’apprezzabilità dell’HyS
Significato del reversed halo sign nei pazienti oncoematologici con neutropenia e febbre
No full textIl presente studio ha lo scopo di valutare la specificità del reversed halo sign (RHS) in pazienti oncoematologici neutropenici
febbrili e di esaminare il RHS in relazione allo stato immunitario
Imaging of ovarian lymphoma
No full textObjective: The aim of the study is to describe the radiological spectrum of appearances of ovarian lymphoma (OL). The manuscript describes the radiological aspects of OL to assist the radiologist in achieving correct orientation of the diagnosis. Methods: We conducted a retrospective evaluation of imaging studies of 98 cases of non-Hodgkin's lymphoma, with extra-nodal localisation (ovaries) in three cases (1 primary, 2 secondary). A literature review was also performed. Results: Of the three evaluated women, one had a primary ovarian involvement and two had a secondary ovarian involvement. The most common lesion characteristics were a well-defined, solid homogeneous and hypoechoic mass at US. CT depicts OL as a well-defined, non-infiltrating, homogeneous hypodense solid mass, with mild contrast enhancement. On T1-weight MRI, OL appears as a homogeneous mass of low signal intensity, which enhances avidly following intravenous gadolinium. Conclusion: Clinical and serological presentation of OL can be similar to that of primary ovarian cancer. As imaging plays a central role in the diagnosis of OL, the radiologist should be familiar with US, CT and MRI appearances of this condition to correctly orient the diagnosis and so avoid unnecessary adnexectomy
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
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