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Curvature Guided Level Set Registration Using Adaptive Finite Elements [chapter]

Andreas Dedner, Marcel Lüthi, Thomas Albrecht, Thomas Vetter
Lecture Notes in Computer Science  
The main contribution of this paper is the application of an adaptive finite element discretization for solving this non-linear PDE.  ...  To avoid restrictions on the topology, we represent the surfaces as a level-set of their signed distance function.  ...  Thomas Kaup, ADI, AO Foundation, Davos, for providing us with the radiological data.  ... 
doi:10.1007/978-3-540-74936-3_53 dblp:conf/dagm/DednerLAV07 fatcat:c32e2nyih5al3cnn4jz7flcrsq

Finite Element Surface Registration Incorporating Curvature, Volume Preservation, and Statistical Model Information

Thomas Albrecht, Andreas Dedner, Marcel Lüthi, Thomas Vetter
2013 Computational and Mathematical Methods in Medicine  
The finite element discretization we present is, while independent of the registration functional, the second main contribution of this paper.  ...  It is formulated as a minimization problem of a sum of several terms representing the desired properties of a registration result: smoothness, volume preservation, matching of the surface, its curvature  ...  In this paper, we present a memory-efficient and flexible schemes using adaptive finite elements; this approach is presented in a general setting.  ... 
doi:10.1155/2013/674273 pmid:24187581 pmcid:PMC3804361 fatcat:c7sz3kzzgrbt3fvf232i4o3cqi

A finite element method to correct deformable image registration errors in low-contrast regions

Hualiang Zhong, Jinkoo Kim, Haisen Li, Teamour Nurushev, Benjamin Movsas, Indrin J Chetty
2012 Physics in Medicine and Biology  
Image-guided adaptive radiotherapy requires deformable image registration to map radiation dose back and forth between images.  ...  An elastic system driven by the displacements of the selected nodes was formulated using a finite element method (FEM) and implemented on the refined mesh.  ...  Briefly, we will use the "demons" algorithm to "align" image features, and take its resultant displacements in highcontrast regions as boundary constraints to guide the finite element model to simulate  ... 
doi:10.1088/0031-9155/57/11/3499 pmid:22581269 pmcid:PMC3360965 fatcat:awcxg7mzezdi7kdrxekfhf3wte

Medially Based Meshing with Finite Element Analysis of Prostate Deformation [chapter]

Jessica R. Crouch, Stephen M. Pizer, Edward L. Chaney, Marco Zaider
2003 Lecture Notes in Computer Science  
The finite element method (FEM) is well suited for use in the non-rigid registration of magnetic resonance spectroscopy images (MRSI) with intraoperative ultrasound images of the prostate because FEM provides  ...  In particular, any finite element based registration method must address the questions of how to generate a mesh from an image and how to solve the system of finite element equations efficiently.  ...  In the prostate case, the m-rep model that was fit to the original image and used to guide mesh construction is transferred onto the image of the deformed prostate and adapted to fit it.  ... 
doi:10.1007/978-3-540-39899-8_14 fatcat:cssqv5tryvdyjoseqqg5nneh6q

A deformable model for tracking tumors across consecutive imaging studies

Gabriela Niculescu, John L. Nosher, M. D. Benjamin Schneider, David J. Foran
2009 International Journal of Computer Assisted Radiology and Surgery  
The strategy of the algorithm is to infer volumetric deformation based upon surface displacements using a linearly elastic finite element model (FEM).  ...  Materials and methods-The method uses the combined power of global and local alignment of pre-and post-treatment computed tomography image data sets.  ...  As the level of computational power continues to grow, deformable registration coupled with finite element analysis is becoming a much more practical approach for medical imaging applications.  ... 
doi:10.1007/s11548-009-0298-x pmid:19774096 pmcid:PMC2747734 fatcat:pi2dxp56lrfnljwprfg7yqm7xy

Improved Non-rigid Registration of Prostate MRI [chapter]

Aloys du Bois d'Aische, Mathieu De Craene, Steven Haker, Neil Weisenfeld, Clare Tempany, Benoit Macq, Simon K. Warfield
2004 Lecture Notes in Computer Science  
This non-rigid registration is based on a finite element method discretization using the mutual information metric with a linear elastic regularization constraint.  ...  The registration is accelerated while preserving accuracy by using an adaptive mesh based on the body-centered cubic lattice and a significantly improved registration is achieved.  ...  This adaptation of the basis functions used to represent the dense deformation field is the main advantage of finite element meshes compared to radial basis functions.  ... 
doi:10.1007/978-3-540-30135-6_103 fatcat:uhu7jdjcujb2zovv5rmfnkizgu

Evaluation of Optimal Control-Based Deformable Registration Model [chapter]

Naleli Jubert Matjelo, Fred Nicolls, Neil Muller
2014 Lecture Notes in Electrical Engineering  
This model is compared with other four well-known variational-based deformable image registration models: elastic, fluid, diffusion and curvature models.  ...  The Pareto fronts are also visualized using level diagrams analysis. ii • Dr. F. Nicolls for the technical support and guidance he offered as my UCT Co-Supervisor for the success of this work.  ...  FDM -Finite Difference Method. FEM -Finite Element Method. FFD -Free-Form Deformation. GFEM -Galerkin Finite Element Method. GN -Gauss Newton method. GAs -Genetic Algorithms.  ... 
doi:10.1007/978-3-319-06764-3_15 fatcat:f2gsfmbxtnfibonbacgzzn5fru

Level-set surface segmentation and registration for computing intrasurgical deformations

Michel A. Audette, Terence M. Peters, Kenneth M. Hanson
1999 Medical Imaging 1999: Image Processing  
The surface identification scheme implements a recent algorithm which imbeds 3D surface segmentation as the level-set of a 4D moving front.  ...  element model of the head.  ...  , and finite-element based estimation of volumetric displacement.  ... 
doi:10.1117/12.348499 dblp:conf/miip/AudetteP99 fatcat:f4mazeynnnb5dmyxe7aztlltvq

Integration and alignment of adaptive optics systems: 10 years of experience at the VLT

Sébastien Tordo, Brent L. Ellerbroek, Michael Hart, Norbert Hubin, Peter L. Wizinowich
2010 Adaptive Optics Systems II  
The Very Large Telescope (VLT) has been equipped with many instruments using adaptive optics such as Shack-Hartmann, curvature or pyramid wavefront sensors.  ...  Such systems are becoming key elements for large telescopes, with increasing types and complexity.  ...  Therefore it is of prime importance to tackle the flexure issues at the instrument mechanical and system design level analyzing them for instance with a finite element method (FEM) analysis.  ... 
doi:10.1117/12.856248 fatcat:plf3elzxqvdd5auj6zegistwym

Knowledge-based Registration for Reliable Correlated Change Detection on High-pier Curved Continuous Rigid Frame Bridge

Zhe Sun, Ying Shi, Wen Xiong, Pingbo Tang
2018 Intelligent Computing in Engineering and Architecture  
The proposed approach uses the joint equilibrium condition between structural elements as domain knowledge to guide the selection of correspondences for point cloud registration and element-level change  ...  This study proposed a knowledge-based registration approach that segments point clouds into structural elements for recovering the correlated torsional and bending behaviors of connected bridge elements  ...  The proposed approach uses the joint equilibrium condition between structural elements as domain knowledge to guide the selection of correspondences for point cloud registration and element-level change  ... 
dblp:conf/egice/SunSXT18 fatcat:wlpftlrm3fhudlihedtgxs53fe

A MRI-guided concentric tube continuum robot with piezoelectric actuation: A feasibility study

Hao Su, Diana C. Cardona, Weijian Shang, Alexander Camilo, Gregory A. Cole, D. Caleb Rucker, Robert J. Webster, Gregory S. Fischer
2012 2012 IEEE International Conference on Robotics and Automation  
The system enables MR image-guided placement of a curved, steerable active cannula.  ...  This 6 degree-of-freedom (DOF) robotic device is piezoelectrically actuated to provide precision motion with joint-level precision of better than 0.03mm, and is fully MRIcompatible allowing simultaneous  ...  The controller consists of four arbitrary frequency waveform synthesizers, one for each set of elements as shown in Fig. 6 (bottom) .  ... 
doi:10.1109/icra.2012.6224550 dblp:conf/icra/SuCSCCRWF12 fatcat:4jof7rxginfsld6ax26qh5bznm

Lasting organ-level bone mechanoadaptation is unrelated to local strain

Behzad Javaheri, Hajar Razi, Stephanie Gohin, Sebastian Wylie, Yu-Mei Chang, Phil Salmon, Peter D. Lee, Andrew A. Pitsillides
2020 Science Advances  
To solve this paradox, we used computed tomography–based, four-dimensional imaging methods and computational analysis to monitor acute and chronic whole-bone shape adaptation and remodeling in vivo.  ...  Bones adapt to mechanical forces according to strict principles predicting straight shape. Most bones are, however, paradoxically curved.  ...  Many studies have attempted to deconstruct this contradiction in design by assessment of deformation in curved bones using strain gauges or finite element modeling (FEM) (4) under load (5) , while others  ... 
doi:10.1126/sciadv.aax8301 pmid:32181340 pmcid:PMC7060058 fatcat:anbt3n3munckxkpdaoxu64rogi

Multidirectional and Topography-based Dynamic-scale Varifold Representations with Application to Matching Developing Cortical Surfaces

Islem Rekik, Gang Li, Weili Lin, Dinggang Shen
2016 NeuroImage  
First, they only use the normals of the surface to measure its geometry and guide the warping process, which overlooks the importance of the orientations of the inherently convoluted cortical sulcal and  ...  To overcome these limitations and improve varifold-based cortical surface registration, we propose two different strategies.  ...  As in (Durrleman et al., 2014) , a set of optimal control points {c k } k=1,…,N c were used to guide the surface warping process.  ... 
doi:10.1016/j.neuroimage.2016.04.037 pmid:27138207 pmcid:PMC4916020 fatcat:6mbchcxskbabnfqlnkbf3udmhy

Finite Element Decomposition of Human Neocortex [chapter]

David A. Batte, Travis S. Chow, Bruce H. McCormick
1998 Computational Neuroscience  
McCormick The finite element decomposition of the human neocortex provides a structural information framework for the visualization and spatial organization of the neocortex at progressive levels of detail  ...  Finite Element Decomposition of the Human Neocortex. (May 1998) Seeling Chow, B.S., Texas A&M University Chair Advisory Committee: Dr. Bruce H.  ...  Because the IVS is a converging approximation to the medial axis, this heuristic step uses the skeleton to guide the level of detail sufficient for the projection.  ... 
doi:10.1007/978-1-4615-4831-7_95 fatcat:rjafsifzmng2xb2mbv2mpyifdy

Estimated in Vivo Postnatal Surface Growth Patterns of the Ovine Main Pulmonary Artery and Ascending Aorta

Bahar Fata, Danielle Gottlieb, John E. Mayer, Michael S. Sacks
2013 Journal of Biomechanical Engineering  
A bicubic Hermite finite element surface representation was developed for the each artery from each animal.  ...  Moreover, this study clearly underscores how functional growth of the PA and AA during postnatal maturation involves complex, local adaptations in tissue formation.  ...  Robert Tamburo for his technical assistance with the image registration project.  ... 
doi:10.1115/1.4024619 pmid:23757175 pmcid:PMC3705821 fatcat:pnvlm52y6rb7lblqhduk325nsa
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