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Brain magnetic resonance (MR) images consist of different structures and features when they are observed at different scales and layers. Conventional non-rigid brain MR image registration methods mainly estimate the optimum transformation by relying on the information of a single layer and this can lead to the loss of information contained in other layers. In this paper, we propose a multi-layer framework...
With the increasing availability of 4D cardiac imaging technologies, the need for efficient spatio-temporal segmentation algorithms for the heart is growing. We propose a new method for heart segmentation in 4D data sets. We efficiently use the established graph cut method for the segmentation of the heart by simultaneously exploiting motion and region cues. We construct a 4D graph designed to find...
This paper describes an automatic algorithm to extract the knee frame of reference from 3D MR isotropic scans. The method ultimately seeks to determine two lines that are tangent to the bottom of the condyles in an axial and a coronal plane. It consists of three major parts, initial detection of the knee joint using Hidden Markov Models, femur segmentation using Random Walker segmentation, and finally...
This paper describes a MRI brain image visualization approach for an undergraduate signal processing course in a liberal art college environment. Owing to the highly mathematical nature of signal processing theory, using visualized biomedical images may increase students' curiosity in both the course itself and the biomedical science in general. The visualization tool is constructed with incremental...
The aim of our study was to develop a 3D model for myocardial wall stress (MWS) evaluation and to test its ability to characterize left ventricular (LV) aging and the effect of aortic valve stenosis (AVS). We studied 65 subjects (45 controls and 20 with AVS) who had a cardiac magnetic resonance (CMR) exam and a measure of central pressures. 3D MWS evaluation combined systolic pressures and an LV geometrical...
The efficiency of a new transit time (Δt) estimator (MSeg) for Pulse Wave Velocity (PWV) estimation is compared with three previously described methods (MUpslope, MFoot, MPoint), in terms of correlation with aging and reproducibility. SSFP and PC acquisitions from 40 subjects (42±15 year), recorded at the level of the aortic arch were studied. Δt was defined as the time shift between the flow curves...
With the development of city, the planning of underground power pipelines becomes more and more difficult, because pipelines are invisible and related with many factors. In order to improve planning efficiencies, a new technique based on virtual reality is presented. A virtual scene is constructed according to the existing pipeline and related environment. And the area partition method is introduced...
The abstract is to be in fully-justified italicized text, at the top of the left-hand column as it is here, below the author information. Use the word “Abstract” as the title, in 12-point Times, boldface type, centered relative to the column, initially capitalized. The abstract is to be in 10-point, single-spaced type, and up to 150 words in length. Leave two blank lines after the abstract, then begin...
How to reduce the risk of damaging the epilepsy patient's vital function areas during resection of epileptic focus remains a challenge for neurosurgeon. Clinically used electrical cortical stimulation (ECS) method shows limits on accuracy, efficiency and reliability. In this study, a cortical function mapping method with 3D visualization was implemented by analyzing and projecting the power change...
Multimodality image registration is a critical issue in image-guided cancer ablation techniques. Focal therapies of prostate cancer are usually monitored using ultrasound imaging, while the dose planning is performed on MRI. In this study, a new multimodality images registration and deformation method, based on the Thin Plate Splines -Rigid Point Matching (TPS-RPM) algorithm, is introduced. The Method...
This paper describes and assesses for the first time the use of a handheld 3D laser scanner for scalp EEG sensor localization and co-registration with magnetic resonance images. Study on five subjects showed that the scanner had an equivalent accuracy, a better repeatability, and was faster than the reference electromagnetic digitizer. According to electrical source imaging, somatosensory evoked potentials...
Stanford type B aortic dissections (TB-AD), which split the descending aorta in a true and false lumen, have better in-hospital survival than type A dissections affecting the ascending aorta. However, short-term and long-term prognosis for the individual patient remains challenging, with one in four patients not surviving after 3 years. Towards a better understanding of the influence of tear location...
Brain glucose uptake was examined in transgenic mice relevant to Alzheimer's disease (APP/PS1) and their control littermates (PS1). Glucose distribution in the brain of the resting animals was measured using 3D-reconstructed autoradiography and analysed by a voxel-wise approach using SPMMouse combined to an MRI-based 3D digital atlas. Prompt and direct indexation of metabolic changes between the two...
A novel approach for shape modeling of the corpus callosum (cc) is introduced where the contours of the cc are extracted by image/volume segmentation, and a Bezier curve is used to connect the vertices of the sampled contours, generating a parametric polynomial representation. These polynomials are shown to maintain the characteristics of the original cc, thus are suitable for classification of populations...
Compressive Sensing (CS) is a nascent sampling and reconstruction paradigm that describes how sparse or compressible signals can be accurately approximated using many fewer samples than traditionally believed. In magnetic resonance imaging (MRI), where scan duration is directly proportional to the number of acquired samples, CS has the potential to dramatically decrease scan time. However, the computationally...
The work reported in this paper aimed at developing and testing an automated method to calculate the biodistribution of a specific PET tracer in mouse brain PET/CT images using an MRI-based 3D digital atlas. Surface-based registration strategy and affine transformation estimation were considered. Such an approach allowed overcoming the lack of anatomical information in the inner regions of PET/CT...
Catheter navigation and placement through the arterial network is a major limitation for clinical procedure. In this article, a specific catheter tip and a modified clinical MRI scanner with an upgraded gradient system are used to steer a catheter through a single Y-shaped bifurcation. Safety aspects are analyzed to avoid the peripheral nerve stimulation (PNS) according to an empirical law of magnetostimulation...
Analysis of fetal biometric parameters on ultrasound images is widely performed and it is essential to estimate the gestational age, as well as the fetal growth pattern. The use of three dimensional ultrasound (3D US) is preferred over other tomographic modalities such as CT or MRI, due to its inherent safety and availability. However, the image quality of 3D US is not as good as MRI and therefore...
We present a feature point detection algorithm which we use for non-rigid registration, illustrated for breast images (mammography, MRI). By associating the continuous intrinsic dimensionality of image structure with the output of a scale saliency algorithm, breast boundary points can be separated from internal feature points. Correspondences established for the breast boundary and internal feature...
The purkinje fiber network (PFN) is a very important conduction system in the endocardial surface of the ventricle, whose structure is crucial in ventricular physiopathology. Traditional medical imaging methods, such as magnetic resonance imaging (MRI) or computed tomography (CT), however, fail to reveal the detailed PFN information. An alternative is to model PFN as idealized self-similar fractal...
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