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Oriented Speckle Reducing Anisotropic Diffusion

Karl Krissian, Carl-Fredrik Westin, Ron Kikinis, Kirby G. Vosburgh
2007 IEEE Transactions on Image Processing  
Harvard Medical School Brigham and Women's Hospital Dep of Radiology Thorn 323 Boston, MA 02115 USA fax : (+1) 617-264-6887 emails: {karl,westin,kikinis}@bwh.harvard.edu; and CIMIT, Cambridge, MA, USA,  ... 
doi:10.1109/tip.2007.891803 pmid:17491469 fatcat:sbcvs2hiqrhslbu6aw65t4bw7a

Directional anisotropic diffusion applied to segmentation of vessels in 3D images [chapter]

Karl Krissian, Gregoire Malandain, Nicholas Ayache
1997 Lecture Notes in Computer Science  
Karl KRISSIAN, Grégroire MALANDAIN, Nicholas AYACHE Equation (2) is a descent of gradient along the energy surface # .  ... 
doi:10.1007/3-540-63167-4_68 fatcat:yuemqmuehrgy3hd26uskpfmhvy

Fast sub-voxel re-initialization of the distance map for level set methods

Karl Krissian, Carl-Fredrik Westin
2005 Pattern Recognition Letters  
Redistancing the implicit surface is currently the most time-consuming stage in Level Set Methods, usually accomplished by applying the Fast Marching algorithm to a binarized image. We propose to apply a faster and linear approximation of the Euclidian Distance while maintaining the sub-voxel accuracy of the interface.
doi:10.1016/j.patrec.2004.12.005 fatcat:6gdahqg76vdshh477nwlq7xouq

Accurate subpixel edge location based on partial area effect

Agustín Trujillo-Pino, Karl Krissian, Miguel Alemán-Flores, Daniel Santana-Cedrés
2013 Image and Vision Computing  
The estimation of edge features, such as sub-pixel position, orientation, curvature and change in intensity at both sides of the edge, from the computation of the gradient vector in each pixel is usually inexact, even in ideal images. In this paper, we present a new edge detector based on an edge and acquisition model derived from the partial area effect, which does not assume continuity in the image values. The main goal of this method consists in achieving a highly accurate extraction of the
more » ... osition, orientation, curvature and contrast of the edges, even in difficult conditions, such as noisy images, blurred edges, low contrast areas or very close contours. For this purpose, we first analyze the influence of perfectly straight or circular edges in the surrounding region, in such a way that, when these conditions are fulfilled, the features can exactly be determined. Afterward, we extend it to more realistic situations considering how adverse conditions can be tackled and presenting an iterative scheme for improving the results. We have tested this method in real as well as in sets of synthetic images with extremely difficult edges, and in both cases a highly accurate characterization has been achieved.
doi:10.1016/j.imavis.2012.10.005 fatcat:ffmuvo3aprephohueh23cl3fi4

A Segmentation and Reconstruction Technique for 3D Vascular Structures [chapter]

Vincent Luboz, Xunlei Wu, Karl Krissian, Carl-Fredrik Westin, Ron Kikinis, Stéphane Cotin, Steve Dawson
2005 Lecture Notes in Computer Science  
In the context of stroke therapy simulation, a method for the segmentation and reconstruction of human vasculature is presented and evaluated. Based on CTA scans, semi-automatic tools have been developed to reduce dataset noise, to segment using active contours, to extract the skeleton, to estimate the vessel radii and to reconstruct the associated surface. The robustness and accuracy of our technique are evaluated on a vascular phantom scanned in different orientations. The reconstructed
more » ... e is compared to a surface generated by marching cubes followed by decimation and smoothing. Experiments show that the proposed technique reaches a good balance in terms of smoothness, number of triangles, and distance error. The reconstructed surface is suitable for real-time simulation, interactive navigation and visualization.
doi:10.1007/11566465_6 fatcat:iibqy3uk4ralboo5clro2dgviq

Model-Based Detection of Tubular Structures in 3D Images

Karl Krissian, Grégoire Malandain, Nicholas Ayache, Régis Vaillant, Yves Trousset
2000 Computer Vision and Image Understanding  
doi:10.1006/cviu.2000.0866 fatcat:etcjvccah5dpbcpbpi3vt6ftke

Comparison of Two Restoration Techniques in the Context of 3D Medical Imaging [chapter]

Miguel A. Rodriguez-Florido, Karl Krissian, Juan Ruiz-Alzola, Carl-Fredrik Westin
2001 Lecture Notes in Computer Science  
In this paper, we compare two restoration techniques applied to 3D angiographies and to femoral CT scans. The first technique uses a Partial Derivative Equation and the second one is based on an extension of adaptive Wiener filters. We first present each method. Then, we discuss and compare the estimation of the local orientations in 3D images obtained either by the smoothed gradient and the principal curvature directions or by the eigenvectors of the structure tensor. A good estimation of the
more » ... rientations is essential because it directs the restoration process. Finally, we compare the restored images on both synthetic and real images for the two studied applications.
doi:10.1007/3-540-45468-3_123 fatcat:g3fheeye5jaqngtfbefk32plky

Analysis of geometrical relations between multiple sclerosis lesions and brain vasculature

Dorota E. Kozinska, Christopher Holland, Karl Krissian, Carl-Fredrik Westin, Charles R. G. Guttmann, Amir A. Amini, Armando Manduca
2004 Medical Imaging 2004: Physiology, Function, and Structure from Medical Images  
A fast implementation of this level set equation [Krissian 2003 , available as free open-source software at www.slicer.org, was used to carry out our experiments.  ... 
doi:10.1117/12.535541 fatcat:hskwjdooenfsvcaxyaxtf7ekly

Automatic Extraction of Blood Vessels in the Retinal Vascular Tree Using Multiscale Medialness

Mariem Ben Abdallah, Jihene Malek, Ahmad Taher Azar, Philippe Montesinos, Hafedh Belmabrouk, Julio Esclarín Monreal, Karl Krissian
2015 International Journal of Biomedical Imaging  
We propose an algorithm for vessel extraction in retinal images. The first step consists of applying anisotropic diffusion filtering in the initial vessel network in order to restore disconnected vessel lines and eliminate noisy lines. In the second step, a multiscale line-tracking procedure allows detecting all vessels having similar dimensions at a chosen scale. Computing the individual image maps requires different steps. First, a number of points are preselected using the eigenvalues of the
more » ... Hessian matrix. These points are expected to be near to a vessel axis. Then, for each preselected point, the response map is computed from gradient information of the image at the current scale. Finally, the multiscale image map is derived after combining the individual image maps at different scales (sizes). Two publicly available datasets have been used to test the performance of the suggested method. The main dataset is the STARE project's dataset and the second one is the DRIVE dataset. The experimental results, applied on the STARE dataset, show a maximum accuracy average of around 94.02%. Also, when performed on the DRIVE database, the maximum accuracy average reaches 91.55%.
doi:10.1155/2015/519024 pmid:25977682 pmcid:PMC4421077 fatcat:zhzout5asfhmjgavyjhrd3kimu

A method for the analysis of the geometrical relationship between white matter pathology and the vascular architecture of the brain

Dorota Kozinska, Christopher M Holland, Karl Krissian, Carl-Fredrik Westin, Charles R.G Guttmann
2004 NeuroImage  
We use a fast implementation of this level set equation developed by Krissian and Westin (2003) .  ... 
doi:10.1016/j.neuroimage.2004.04.014 pmid:15275923 fatcat:usvngh4hlrdihlbbqb6fzq5lim

A Variational Approach for 3D Motion Estimation of Incompressible PIV Flows [chapter]

Luis Alvarez, Carlos Castaño, Miguel García, Karl Krissian, Luis Mazorra, Agustín Salgado, Javier Sánchez
Lecture Notes in Computer Science  
Estimation of motion has many applications in fluid analysis. Lots of work has been carried out using Particle Image Velocimetry to design experiments which capture and measure the flow motion using 2D images. Recent technological advances allow capturing 3D PIV image sequences of moving particles. In this context, we propose a new threedimensional variational (energy-based) technique. Our technique is based on solenoidal projection to take into account the incompressibility of the real flow.
more » ... uses the result of standard flow motion estimation techniques like iterative cross-correlation or pyramidal optical flow as an initialization, and improves significantly their accuracies. The performance of the proposed technique is measured and illustrated using numerical simulations.
doi:10.1007/978-3-540-72823-8_72 dblp:conf/scalespace/AlvarezCGKMSS07 fatcat:omlv5yaovfauzhhnc6ebjdebvm

Denoising of MRI images using fast NLM

Vandana Hanchate, Kalyani Joshi
2020 Indonesian Journal of Electrical Engineering and Computer Science  
Karl Krissian et al. [5] depicted Noise-Driven Anisotropic Diffusion Filtering of MRI. This method of filtering is proposed to remove the Rician noise from magnetic resonance images.  ... 
doi:10.11591/ijeecs.v18.i1.pp135-141 fatcat:zi3cgfejr5cffgzk44s6oqz7ve

New approaches to computer-based interventional neuroradiology training

Xunlei Wu, Vincent Pegoraro, Vincent Luboz, Paul F Neumann, Ryan Bardsley, Steven Dawson, Stephane Cotin
2005 Studies in Health Technology and Informatics  
Karl Krissian from SPL and Dr. James Rabinov in MGH for providing us valuable feedback on anatomical segmentation.  ... 
pmid:15718806 fatcat:xl4f3lbsh5as7ml7jc6qmnl2fy

Standardized evaluation methodology and reference database for evaluating coronary artery centerline extraction algorithms

Michiel Schaap, Coert T. Metz, Theo van Walsum, Alina G. van der Giessen, Annick C. Weustink, Nico R. Mollet, Christian Bauer, Hrvoje Bogunović, Carlos Castro, Xiang Deng
2009 Medical Image Analysis  
Karl Krissian is funded by the Spanish government and the University of Las The column 'Time' indicates if information is provided about the computational time of the algorithm.  ...  KnowledgeBasedMinPath (Krissian et al., 2008) and VirtualContrast (Wang and Smedby, 2008) ).  ... 
doi:10.1016/j.media.2009.06.003 pmid:19632885 pmcid:PMC3843509 fatcat:zakl4k2a6jgf3ezpigkfcxv27a

Flux-based anisotropic diffusion applied to enhancement of 3-D angiogram

K. Krissian
2002 IEEE Transactions on Medical Imaging  
Harvard Medical School Brigham and Women's Hospital Dep of Radiology Thorn 323 Boston, MA 02115 USA (karl@bwh.harvard.edu) 1 This work was supported by the European Union TMR project on Viscosity Solutions  ... 
doi:10.1109/tmi.2002.806403 pmid:12575880 fatcat:e5spezbfrbatflhdigod3jx37u
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