Search results for "COMPUTED TOMOGRAPHY"

Interferon alfa–induced sarcoidosis resolving without drug withdrawal

2016

Sarcoidosis is an uncommon systemic granulomatous disease of unknown origin affecting lung, skin, liver, and other tissues. Noncaseating granulomas in the involved organs are the hallmark of this disease. An exaggerated immune response to an unknown antigenic stimulus could play a role in sarcoidosis development. Lung is one of the most frequently involved organs.1 Manifestations range from alveolitis to granulomatous infiltration of alveoli, bronchi, and blood vessels. The end stage of lung sarcoidosis is development of interstitial fibrosis with “honeycombing” of lung parenchyma. Interferon alfa in association with ribavirin is the treatment of choice for hepatitis C. Early treatment of a…

Influence of root width and dentin wall thickness evaluated by endoscopy upon the outcome of periapical surgery. A cohort study.

2020

Background: An analysis was made of the correlation between root width, the thickness of the remaining dentinal wall as determined by endoscopy, and the outcome of periapical surgery. Material and Methods: A retrospective cohort study was carried out involving patients subjected to periapical surgery between 2017 and 2019 at the University of Valencia (Valencia, Spain). One year after surgery, cone-beam computed tomography (CBCT) was used to evaluate healing against the preoperative volumes. The maximum root width was measured on the postoperative CBCT scan at the apical section of the treated root. This measurement was transferred to the intraoperative endoscopic image, where the minimum r…

Determination of optimal fluoroscopic angulations for aorto-coronary ostial interventions from coronary computed tomography angiography.

2020

Abstract Background An optimal aorto-coronary angiographic projection, characterized by an orthogonal visualization of the proximal coronary artery, is crucial for interventional success. We determined the distribution of optimal C-arm positions and assessed their feasibility by invasive coronary angiography. Methods Orthogonal aorto-coronary ostial angulations were determined in 310 CT data sets. In 100 patients undergoing subsequent invasive angiography, we assessed if the CT-predicted angulations were achievable by the C-arm system. If the predicted projection was not achievable due to mechanical constraints of the C-arm system, the most close, achievable angulation was determined. Patie…

RUOLO DELL'ANGIO-TC NELLA DIAGNOSI DI URGENZA DI ANGIODISPLASIA INTESTINALE ILEALE: UNA RARA CAUSA DI SANGUINAMENTO

2018

A Predictive System to Classify Preoperative Grading of Rectal Cancer Using Radiomics Features

2022

Although preoperative biopsy of rectal cancer (RC) is an essential step for confirmation of diagnosis, it currently fails to provide prognostic information to the clinician beyond a rough estimation of tumour grade. In this study we used a risk classification to stratified patient in low-risk and high-risk patients in relation to the disease free survival and the overall survival using histopathological post-operative features. The purpose of this study was to evaluate if low-risk and high-risk RC can be distinguished using a CT-based radiomics model. We retrospectively reviewed the preoperative abdominal contrast-enhanced CT of 40 patients with RC. CT portal-venous phase was used for manua…

Simple computation of the approximated modulation transfer function (MTF) using spreadsheet-software: method and evaluation in five maxillofacial CBC…

2019

OBJECTIVES: To develop a simple way to compute the approximated modulation transfer function (MTF) manually using conventional spreadsheet software. METHODS: Basing on an edge-image a method was developed, facilitating computation of the edge spread and line spread function in open-source spreadsheet software (Gnumeric; http://projects.gnome.org/gnumeric/downloads.shtml). By means of the integrated fast Fourier transformation Fourier coefficients are obtained from the line spread function which can then be plotted vs spatial frequency to obtain MTF-plots. For the experimental evaluation an edge test object was exposed in five commercial CBCT devices for maxillofacial applications. RESULTS: …

Automatic segmentation of the spine by means of a probabilistic atlas with a special focus on ribs suppression

2017

[EN] Purpose: The development of automatic and reliable algorithms for the detection and segmentation of the vertebrae are of great importance prior to any diagnostic task. However, an important problem found to accurately segment the vertebrae is the presence of the ribs in the thoracic region. To overcome this problem, a probabilistic atlas of the spine has been developed dealing with the proximity of other structures, with a special focus on ribs suppression. Methods: The data sets used consist of Computed Tomography images corresponding to 21 patients suffering from spinal metastases. Two methods have been combined to obtain the final result: firstly, an initial segmentation is performe…

Automated detection of lung nodules in low-dose computed tomography

2007

A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector computed-tomography (CT) images has been developed in the framework of the MAGIC-5 Italian project. One of the main goals of this project is to build a distributed database of lung CT scans in order to enable automated image analysis through a data and cpu GRID infrastructure. The basic modules of our lung-CAD system, consisting in a 3D dot-enhancement filter for nodule detection and a neural classifier for false-positive finding reduction, are described. The system was designed and tested for both internal and sub-pleural nodules. The database used in this study consists of 17 low…

[68Ga]Ga-DATA5m.SA.FAPi PET/CT: Specific Tracer-uptake in Focal Nodular Hyperplasia and potential Role in Liver Tumor Imaging.

2020

Automated detection of patient movement during a CBCT scan based on the projection data.

2015

Objectives To develop an automated procedure to detect patient motion on the projection images acquired during a cone beam computed tomography (CBCT) scan and to evaluate the method's feasibility on small real-world CBCT images in relation to visual assessment. Methods Based on optical flow theory, software was developed using the sequence of the projection images of a CBCT machine for automated detection of patient motion. Averaged acceleration vectors were used as measurement data and compared with visual assessment of the projection images displayed as video. Seventy-nine CBCT data sets (small field-of-view: 40 mm) from our patient database were selected in a sequential fashion and evalu…