5,407 research outputs found
Interobserver agreement on non-contrast computed tomography interpretation for diagnosis of urolithiasis in patients with acute flank pain
OBJECTIVE: To evaluate the interobserver agreement on non-contrast computed tomography interpretation by a group of experienced abdominal radiologists, for the study of urolithiasis in patients presenting acute flank pain. MATERIALS AND METHODS: Prospective study of 52 patients submitted to non-contrast enhanced helical computed tomography. The images were subsequently analyzed by three independent observers, with the interobserver agreement assessed by means of the kappa (kappa) statistical method. The following parameters were analyzed: a) presence, localization and measurement of ureteral calculi; b) intrarenal calyceal system dilatation; c) perirenal fat heterogeneity; d) ureteral dilatation; e) ureteral wall edema (halo sign). RESULTS: Ureteral calculi were found in 40 of 52 patients (77%). The interobserver agreement was almost perfect as regards identification of ureteral calculi (kappa = 0.89) and ureteral dilatation (kappa = 0.87), substantial for calyceal system dilatation (kappa = 0.77), and moderate for perirenal fat heterogeneity (kappa = 0.55) and ureteral wall edema (kappa = 0.56). CONCLUSION: Non-contrast-enhanced abdominal computed tomography presents high reproducibility in the evaluation of urolithiasis and secondary signs of the calyceal system obstruction.OBJETIVO: Avaliar a reprodutibilidade da tomografia computadorizada sem contraste na avaliação da litíase ureteral e os sinais secundários de obstrução do sistema coletor em pacientes com cólica renal aguda. MATERIAIS E MÉTODOS: Estudo prospectivo de 52 pacientes com diagnóstico clínico de cólica renal aguda submetidos a exame de tomografia computadorizada de abdome sem contraste. Os exames foram realizados com técnica helicoidal e posteriormente analisados por três observadores independentes, com a concordância interobservador avaliada pelo método estatístico kappa (kapa). Foram analisados os parâmetros: a) presença, localização e mensuração dos cálculos ureterais; b) dilatação do sistema coletor intra-renal; c) heterogeneidade da gordura perirrenal; d) dilatação ureteral; e) edema da parede ureteral (sinal do halo). RESULTADOS: Foram encontrados 40 cálculos ureterais na tomografia computadorizada (77%). A concordância interobservador para a identificação do cálculo ureteral e da dilatação ureteral foi quase perfeita (kapa = 0,89 e kapa = 0,87, respectivamente), substancial para dilatação do sistema coletor intra-renal (kapa = 0,77) e moderada para heterogeneidade da gordura perirrenal e para edema da parede ureteral (kapa = 0,55 e kapa = 0,56, respectivamente). CONCLUSÃO: A tomografia computadorizada de abdome sem contraste apresenta elevada reprodutibilidade na avaliação da litíase ureteral e dos sinais secundários de obstrução do sistema coletor.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de Diagnóstico por ImagemColégio Brasileiro de Radiologia e Diagnóstico por ImagemUNIFESP, EPM, Depto. de Diagnóstico por ImagemSciEL
A Test Stand System for High-Energy Physics Applications
The Front-End R&D group at Fermilab has been developing pixel hybridized modules and silicon strip detectors for the past decade for high-energy physics experiments. To accomplish this goal, one of the activities the group has been working on includes the development of a flexible high-speed and high-bandwidth data acquisition and test system to characterize front-end electronics. In this paper, we present a general purpose PCI-based test stand system developed to meet the stringent requirements of testing silicon strip and pixel detectors. The test stand is based on a platform that is flexible enough to be adapted to different types of front-end electronics. This system has been used to test the performance of the electronics for different experiments such as BTeV, CDF, CMS, and Phenix. The paper presents the capabilities of the system and how it can be adapted to meet the testing requirements of different applications
Plan S - FAQ's
A report on Plan S and the cOAlition S collaboration, with particular focus on the role of repositories and green OA
The INFN Open Access Repository Conceptual Design Report
This document presents the conceptual design of a long-term institutional Open Access Repository for the INFN. The motivations and the objectives as well as the state-of-the-art technologies available and some already existing examples are discussed. Both the current implementation and the proposed long-term solution are presented, together with the human and financial resources needed
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