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A new approach for segmenting different anatomical regions in dental Computed Tomography (CT) studies is presented in this paper. It is expected that the proposed approach will help automate different tissues regions by providing initial boundary points for deformable models or seed points for split and merge segmentation algorithms. Preliminary results obtained for dental CT studies of dentate and...
The integration of patient digital photographic images with medical imaging studies can serve as a powerful identification tool and prevent medical errors. Photographs can also provide supplemental clinical information that can improve diagnosis. Digital cameras can easily and inexpensively be incorporated in all medical imaging devices such that point-of-care photographs can be obtained along with...
The CT limited-angle problem has been discussed for many years because of the strong demand in medical imaging applications. However as a severely ill-posed problem, it is hard to achieve accurate reconstruction if no additional prior information is given. Recently, an ART+TV reconstruction method was proposed. With the prior knowledge of image sparsity, the ART+TV gives high quality reconstructions...
ChromAIX is an ASIC for fast single photon-counting designed to study the feasibility of energy-resolved photon-counting human Spectral CT. It allows for reading out 4 × 16 pixels of a direct converting sensor made of Cd[Zn]Te with a pixel pitch of about 300μm. It supports K-edge imaging [3]. After thorough electrical testing reported in [6] characterization under g- and X-rays was done giving promising...
A prototype stationary source for medical imaging is evaluated. X-ray focal spot diameters of less than 0.2 mm are formed with beam currents of up to 75 mA at beam energies of 30 keV.
The generation of digitally reconstructed radiographs (DRRs) is a significant procedure in several medical imaging applications such as 2D/3D image registration. Also, digitally reconstructed radiographs play an important role in modern radiation therapy. They are planar X-rays that can be generated from the same data sets used for the planning CT scan, taken with the patient in the treatment position...
In this paper, we propose a new methodology for the segmentation and retrieval system for Computed Tomography (CT) brain images. For the segmentation part, two segmentation techniques are considered which are modified FCM with population-diameter independent (PDI) and expectation-maximization (EM) segmentation. However, only one of the techniques is selected based on the average intensity in order...
A novel compact rotating anode X-ray tube with high electron focusing capability of a paired magnetic quadrupole system is presented. The tube offers a high power density even at relatively low tube voltage, where the X-ray flux at a detector behind an object is very limited. Its various focal spot deflection capabilities help to reduce image artifacts, enhance the spatial resolution of the corresponding...
The visualization of 3D models of the patient's body emerges as a priority in surgery. In this paper two different visualization and interaction systems are presented: a virtual interface and a low cost multi-touch screen. The systems are able to interpret in real-time the user's movements and can be used in the surgical pre-operative planning for the navigation and manipulation of 3D models of the...
Brain tumor is one of the leading cause of death in recent years. This paper proposes the tumor detection in CT scan brain images, which can assist the medical image diagnosis system. The method proposed here makes use of association rule mining technique to classify the CT scan brain images. It combines the low-level features extracted from images and high level knowledge from specialists. The proposed...
Segmentation and analysis of blood vessels is an important issue in medical imaging. In 3D cerebral angiographic data, the vascular signal is however hard to accurately detect and can, in particular, be disconnected. In this article, we present a procedure utilising both linear, Hessian-based and morphological methods for blood vessel edge enhancement and reconnection. More specifically, multi-scale...
In medical imaging, anatomical and other structures such as urinary stones, are often extracted with the aid of active contour/ surface models. Active surface-based methods have robustness limitations and are computationally expensive. In this paper we present a morphological method based on attribute filters and the newly presented sphericity attribute. The operators involved, extract the targeted...
This paper gives an overview of the Medipix2 x-ray detector and its use in medical imaging, with the MARS-CT scanner (MARS, Medipix All Resolution System) as an example. The Medipix2 chip is a photon counting pixel detector with the ability of energy discrimination. It was developed at CERN and is composed of a sensor layer bump bonded to electronics layer. It has 256??256 pixels, each one covering...
A method extending the functionality of silicon photomultipliers (SiPMs) has been developed. It enables the use of SiPMs for quantifying high radiation fluxes in current mode as well as in pulse mode measurements for counting and characterizing individual gamma-ray or X-ray photons when coupled to scintillators. This opens new possibilities for multimodal medical imaging by providing the means for...
Automatic coronary artery centerline extraction from 3D CT Angiography (CTA) has significant clinical importance for diagnosis of atherosclerotic heart disease. The focus of past literature is dominated by segmenting the complete coronary artery system as trees by computer. Though the labeling of different vessel branches (defined by their medical semantics) is much needed clinically, this task has...
Recent developments in medical imaging technology have enabled us to acquire high-resolution datasets within a few minutes. It is important for a physician to recognize three-dimensional structure of vessels prior to any vascular treatments. However, extracting this structure is not a simple image processing task. In this paper, we propose an algorithm to extract hepatic artery from CT datasets through...
Atlas-based segmentation has been shown to provide promising results to delineate critical structures for radiotherapy planning. However, it requires to have a reference image with its reference segmentation available. Classical methods used to build an average segmentation can lead to over-segmentation in case of high variability among the manual segmentations. We propose in this paper a consensus-based...
Most software systems for oral implantology are based on a multi-view approach, often accompanied with a 3D rendered model. A more integrated and realistic 3D approach for implant surgery is desirable, in order to gain a deep and sure knowledge of patient's anatomy before inserting the implants, thus reducing the risk of damaging surrounding structures. We present a 3D software system where computer...
Considering the increasing use of medical imaging and other technologies like electron beam melting (EBM), there have been attempts to improve the quality of the hip endoprostheses by increasing the porosity of their surface. This study presents a type of mesh structure with different dimensions that is designed and simulated in order to determine in what way its dimensions may influence the distribution...
Medical diagnosis is often made on the basis of information from visualisation instruments such as CT scanners. This information is currently used by medics only and, in most cases, browsed manually. This paper presents technical issues which are prerequisite to decision-support systems which analyse such data and provide new ways to present the data so as to make it most useful to clinicians, taking...
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