Search results for "Sound"
showing 10 items of 1845 documents
Maternal and perinatal outcomes of pregnant women with SARS-CoV-2 infection
2021
WOS:000613461600006 PubMed ID: 32926494 Objectives To evaluate the maternal and perinatal outcomes of pregnancies affected by SARS-CoV-2 infection. Methods This was a multinational retrospective cohort study including women with a singleton pregnancy and laboratory-confirmed SARS-CoV-2 infection, conducted in 72 centers in 22 different countries in Europe, the USA, South America, Asia and Australia, between 1 February 2020 and 30 April 2020. Confirmed SARS-CoV-2 infection was defined as a positive result on real-time reverse-transcription polymerase chain reaction (RT-PCR) assay of nasopharyngeal swab specimens. The primary outcome was a composite measure of maternal mortality and morbidity…
3D segmentation of abdominal aorta from CT-scan and MR images
2012
International audience; We designed a generic method for segmenting the aneurismal sac of an abdominal aortic aneurysm (AAA) both from multi-slice MR and CT-scan examinations. It is a semi-automatic method requiring little human intervention and based on graph cut theory to segment the lumen interface and the aortic wall of AAAs. Our segmentation method works independently on MRI and CT-scan volumes and has been tested on a 44 patient dataset and 10 synthetic images. Segmentation and maximum diameter estimation were compared to manual tracing from 4 experts. An inter-observer study was performed in order to measure the variability range of a human observer. Based on three metrics (the maxim…
EP07.12: Calcar avis: a normal cerebral anatomic structure that can also mimic parenchymal pathology
2019
Imaging of calcified hepatic lesions: spectrum of diseases
2021
Hepatic calcifications have been increasingly identified over the past decade due to the widespread use of high-resolution Computed Tomography (CT) imaging. Calcifications can be seen in a vast spectrum of common and uncommon diseases, from benign to malignant, including cystic lesions, solid neoplastic masses, and inflammatory focal lesions. The purpose of this paper is to present an updated review of CT imaging findings of a wide range of calcified hepatic focal lesions, which can help radiologists to narrow the differential diagnosis.
A chamber to test the response of radon detectors to changing environmental conditions.
2011
Radon risk assessment is carried out with accurate measurements with active or passive instrumentation. All radon detectors must be calibrated and tested using a radon chamber containing a known concentration of radon produced by specific sources of 226Ra. Some of the chambers can also be used to test the response of detectors as a function of environmental conditions. In this case, it can be inferred a calibration curve with respect to changing of the parameter considered. For this aim, a new chamber radon was designed and realized to perform both calibration of instruments and to study the detector response in a large range of variation of the environmental parameters (pressure, 700 - 110…
Ultrasonographic and radionuclide detection of hepatocellular carcinoma in cirrhotics with low alpha-fetoprotein levels
1984
A total of 67 cirrhotic patients with clinically suspected neoplastic degeneration and low alpha-fetoprotein levels were assessed prospectively with ultrasound and gold (198Au) scintigraphy. Ultrasound showed space-occupying lesions in 22 of the 24 patients who had a final diagnosis of hepatocellular carcinoma (HCC) (sensitivity, 95.8%) and excluded the presence of HCC in 37 of the 43 patients with cirrhosis only (specificity, 86.0%; efficiency, 90.8%). Scintigraphy demonstrated a cold defect in 22 of the 24 patients who had a final diagnosis of HCC (sensitivity, 95.8%) and excluded the presence of HCC in 22 of the 43 patients with cirrhosis only (specificity, 51.1%; efficiency, 69.8%). It …
Impact of BMI on Preoperative Axillary Ultrasound Assessment in Patients With Early Breast Cancer
2020
Background The accuracy of axillary ultrasound (AUS) with fine-needle aspiration with varying patient body mass index (BMI) is still unclear. The aim of our study was to evaluate whether the US features of axillary lymph nodes changes with BMI of patients. Patients and methods A retrospective review was performed involving 144 out of 270 patients with early breast cancer who underwent breast surgery with sentinel lymph node biopsy. Diagnostic efficacy of AUS in preoperative axillary nodal staging was assessed in relation to BMI. Results Negative predictive values of AUS for the overweight and obese groups were statistically significantly lower compared to the normal/underweight group (p=0.0…
Submarine canyon morphologies in the Gulf of Palermo (Southern Tyrrhenian Sea) and possible implications for geo-hazard
2011
12 pages, 12 figures, 1 table.
The automated assesment of artery hemodynamic parameters from ultrasound video
2012
The custom designed video processing software for analysis of B-mode and Doppler-mode ultrasound video has been proposed in this work. The software allows adjusting user-defined thresholds and tolerance levels to enhance contour detection in noisy and artifacted ultrasound images. The developed software is able to evaluate 16 hemodynamic parameters (artery diameter, pulse rate and flow velocity related parameters) in each cardiac cycle. The measurements were performed intermittently recording artery diameter (B-mode) and flow velocity (Doppler-mode). Software has validated in femoral artery measurements. The hemodynamic parameters computed by software were consistent with those obtained by …
Cardiac output following fetoscopic coagulation of major placental vessels in fetal sheep.
2008
Objectives To measure changes in cardiac output (CO) after partial cord occlusion in fetal sheep in order to investigate pathophysiological fetal adaptation mechanisms in a simulated acute placental insufficiency model under standardized conditions, with the aim of finding relevant methods for monitoring human fetuses during stress situations. Methods We used minimally invasive, percutaneous endoscopic techniques to close umbilical vessels in mid-gestational fetal sheep. Placental blood flow was reduced by preferentially closing first arterial and then the concomitant venous umbilical vessels within a short time interval. The investigations were carried out on 11 pregnant ewes at a median g…