Search results for "COMPUTED TOMOGRAPHY"
showing 10 items of 713 documents
Three-Dimensional Separation and Characterization of Fractures in X-Ray Computed Tomographic Images of Rocks
2020
Open fractures can affect petrophysical properties of their host rock masses, as well as fluid transport and storage, so characterization of them is important to both industrial and research scientists. X-ray Computed Tomography (CT), a non-destructive technique for 3D imaging of various materials, shows such fractures well in rock samples. However, separation and characterization of fractures in CT data is complicated when a scanned sample contains narrow and intersecting fractures, because narrow fractures become blurred when thinner than the scanner resolution and their value approximates the one of the matrix, and because intersecting features are difficult to individually characterize.…
Ex vivo measurement reliability using two different cbct scanners for orthodontic purposes
2012
Background There are many cone beam computed tomography (CBCT) scanners available on the market: detector technology, algorithm precision, and scanner settings influence image quality. The aim of this study was to compare the accuracy of linear measurements made on images of the same sample obtained using two different CBCT scanners. Methods Twenty-eight linear measurements between orthodontic anatomical landmarks that were marked with gutta-percha points on a fresh sacrificed lamb head were taken three times. The head was scanned with two CBCT scanners using different scanning parameters. Digital Imaging and Communications in Medicine (DICOM) images were reconstructed and the same measurem…
Extraction of Airways from CT (EXACT'09)
2012
Contains fulltext : 107854.pdf (Publisher’s version ) (Open Access) This paper describes a framework for establishing a reference airway tree segmentation, which was used to quantitatively evaluate fifteen different airway tree extraction algorithms in a standardized manner. Because of the sheer difficulty involved in manually constructing a complete reference standard from scratch, we propose to construct the reference using results from all algorithms that are to be evaluated. We start by subdividing each segmented airway tree into its individual branch segments. Each branch segment is then visually scored by trained observers to determine whether or not it is a correctly segmented part o…
A GIANT ANEURYSM OF PROPER HEPATIC ARTERY IN A CRYOGLOBULINEMIC PATIENT ON HEMODIALYSIS: A CASE REPORT.
2014
Introductrion. Hepatic artery aneurysms (HAAs) are unusual vascular lesions often associated with many different pathological conditions. Most of reported cases are described in association with connective tissue diseases, such as polyarteritis nodosa and systemic lupus erythematosus. Case report. We observed a 52-year-old man with hypertension and HCV-related cryoglobulinemia complicated by end stage renal disease on replacement therapy by hemodialysis. He was admitted to our hospital because of the worsening of blood pressure values (170/110 mmHg) associated to new onset abdominal pain. After an initial physical examination, that showed a periumbelical bruit associated to a pulsatile mass…
LA DIAGNOSI DI DOLICOECTASIA DELLA CAROTIDE INTERNA E LE SUE IMPLICAZIONI CLINICO-PATOLOGICHE
2018
Are pancreatic calcifications specific for the diagnosis of chronic pancreatitis? A multidetector-row CT analysis.
2009
AIM: To retrospectively establish the most frequently encountered diagnoses in patients with pancreatic calcifications and to investigate whether the association of certain findings could be helpful for diagnosis. MATERIALS AND METHODS: One hundred and three patients were included in the study. The location and distribution of calcifications; presence, nature, and enhancement pattern of pancreatic lesions; pancreatic atrophy and ductal dilatation were recorded. Differences between patients with chronic pancreatitis and patients with other entities were compared by using Fisher's exact test. RESULTS: Patients had chronic pancreatitis (n=70), neuroendocrine tumours (n=14), intraductal papilla…
Forensic investigation in aircraft accident with the aid of CT (MSCT), and Magnetic Resonance Imaging (MRI): our experience
2011
The autors report their experience in a case of air disaster in which a Tuninter airlines ATR 72 fallen down into the sea near Capo Gallo coast (Palermo, Italy) with 39 persons on board, resulting in six-teen victims. In the present contribute the authors argued the causes of the death and analysed patternes of injuries sustained by passengers involved in the fatal airplane accident using the conventional autopsy combined with postmortem Multi Slice Computed Tomography (MSCT) examination.
On-line tools for microscopic and macroscopic monitoring of microwave processing
2007
International audience; Direct monitoring of temperature, chemistry and microstructure is required to understand microwave heating in more detail, in order to fully exploit the unique features this non-equilibrium processing method can offer. In this paper, we show first that microwave radiometry can be used to follow volumetrically the thermal trajectory of microwave-heated aluminium powder. In-situ Raman spectroscopy is then shown to evidence thermal gradients between diamond and silicon grains in a binary powder mixture. Finally, perspectives and preliminary results of microstructural analysis obtained from X-ray microtomography are presented.
Anam-Net: Anamorphic Depth Embedding-Based Lightweight CNN for Segmentation of Anomalies in COVID-19 Chest CT Images.
2021
Chest computed tomography (CT) imaging has become indispensable for staging and managing coronavirus disease 2019 (COVID-19), and current evaluation of anomalies/abnormalities associated with COVID-19 has been performed majorly by the visual score. The development of automated methods for quantifying COVID-19 abnormalities in these CT images is invaluable to clinicians. The hallmark of COVID-19 in chest CT images is the presence of ground-glass opacities in the lung region, which are tedious to segment manually. We propose anamorphic depth embedding-based lightweight CNN, called Anam-Net, to segment anomalies in COVID-19 chest CT images. The proposed Anam-Net has 7.8 times fewer parameters …
Active unilateral condylar hyperplasia : assessment of the usefulness of single photon emission computed tomography
2020
[Background] This study aims to evaluate whether the uptake difference by the condyles evaluated using single photon emission computed tomography (SPECT) examination is useful for predicting the activity of the feature and the advance of this pathology.