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Deformable Image Registration

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https://www.readbyqxmd.com/read/27917580/a-combined-registration-and-finite-element-analysis-method-for-fast-estimation-of-intraoperative-brain-shift-phantom-and-animal-model-study
#1
Amrollah Mohammadi, Alireza Ahmadian, Shahram Rabbani, Ehsan Fattahi, Shapour Shirani
BACKGROUND: Finite element models for estimation of intraoperative brain shift suffer from huge computational cost. In these models, image registration and finite element analysis are two time-consuming processes. METHODS: The proposed method is an improved version of our previously developed Finite Element Drift (FED) registration algorithm. In this work the registration process is combined with the finite element analysis. In the Combined FED (CFED), the deformation of whole brain mesh is iteratively calculated by geometrical extension of a local load vector which is computed by FED...
December 4, 2016: International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS
https://www.readbyqxmd.com/read/27908182/prostate-deformation-from-inflatable-rectal-probe-cover-and-dosimetric-effects-in-prostate-seed-implant-brachytherapy
#2
Jun Lian, Yeqin Shao, Larry D Potter, Ronald C Chen, Jordan A Holmes, Eleanor A Pryser, Jie Shen, Dinggang Shen, Andrew Z Wang
PURPOSE: Prostate brachytherapy is an important treatment technique for patients with localized prostate cancer. An inflatable rectal ultrasound probe cover is frequently utilized during the procedure to adjust for unfavorable prostate position relative to the implant grid. However, the inflated cover causes prostate deformation, which is not accounted for during dosimetric planning. Most of the therapeutic dose is delivered after the procedure when the prostate and surrounding organs-at-risk are less deformed...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908166/improved-targeting-accuracy-of-lung-tumor-biopsies-with-scanning-beam-digital-x-ray-tomosynthesis-image-guidance
#3
Geoff Nelson, Meng Wu, Cameron Hinkel, Ganesh Krishna, Tobias Funk, Jarrett Rosenberg, Rebecca Fahrig
PURPOSE: Electromagnetic navigation bronchoscopy (ENB) provides improved targeting accuracy during transbronchial biopsies of suspicious nodules. The greatest weakness of ENB-based guidance is the registration divergence that exists between the planning CT, acquired days or weeks before the intervention, and the patient on the table on the day of the intervention. Augmenting ENB guidance with real-time tomosynthesis imaging during the intervention could mitigate the divergence and further improve the yield of ENB-guided transbronchial biopsies...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27894001/multiresolution-extended-free-form-deformations-xffd-for-non-rigid-registration-with-discontinuous-transforms
#4
Rui Hua, Jose M Pozo, Zeike A Taylor, Alejandro F Frangi
Image registration is an essential technique to obtain point correspondences between anatomical structures from different images. Conventional non-rigid registration methods assume a continuous and smooth deformation field throughout the image. However, the deformation field at the interface of different organs is not necessarily continuous, since the organs may slide over or separate from each other. Therefore, imposing continuity and smoothness ubiquitously would lead to artifacts and increased errors near the discontinuity interface...
November 9, 2016: Medical Image Analysis
https://www.readbyqxmd.com/read/27887983/method-of-evaluating-respiratory-induced-organ-motion-by-vector-volume-histogram
#5
Hideharu Miura, Shuichi Ozawa, Hideo Kawabata, Yoshiko Doi, Masahiro Kenjou, Kengo Furukawa, Minoru Nakao, Yasushi Nagata
PURPOSE: Published organ motion data have been collected from measurements of a limited number of points within the organ, the centroid, or the edge of the organ. These are derived from the spatial characteristics of respiratory induced motion; however, this approach does not consider non-rigid organ deformation. We propose a novel quantitative method for evaluating respiratory induced organ motion using Deformable Image Registration (DIR). METHOD: Two phases from a 4-dimensional computed tomography (4D CT) dataset at maximum inspiration and expiration were each taken from five patients...
November 22, 2016: Physica Medica: PM
https://www.readbyqxmd.com/read/27875186/visualizing-shape-deformations-with-variation-of-geometric-spectrum
#6
Jiaxi Hu, Hajar Hamidian, Zichun Zhong, Jing Hua
This paper presents a novel approach based on spectral geometry to quantify and visualize non-isometric deformations of 3D surfaces by mapping two manifolds. The proposed method can determine multi-scale, non-isometric deformations through the variation of Laplace-Beltrami spectrum of two shapes. Given two triangle meshes, the spectra can be varied from one to another with a scale function defined on each vertex. The variation is expressed as a linear interpolation of eigenvalues of the two shapes. In each iteration step, a quadratic programming problem is constructed, based on our derived spectrum variation theorem and smoothness energy constraint, to compute the spectrum variation...
January 2017: IEEE Transactions on Visualization and Computer Graphics
https://www.readbyqxmd.com/read/27870999/sparse-bayesian-registration-of-medical-images-for-self-tuning-of-parameters-and-spatially-adaptive-parametrization-of-displacements
#7
Loïc Le Folgoc, Hervé Delingette, Antonio Criminisi, Nicholas Ayache
We extend Bayesian models of non-rigid image registration to allow not only for the automatic determination of registration parameters (such as the trade-off between image similarity and regularization functionals), but also for a data-driven, multiscale, spatially adaptive parametrization of deformations. Adaptive parametrizations have been used with success to promote both the regularity and accuracy of registration schemes, but so far on non-probabilistic grounds - either as part of multiscale heuristics, or on the basis of sparse optimization...
November 9, 2016: Medical Image Analysis
https://www.readbyqxmd.com/read/27868345/conosurf-open-source-3d-scanning-system-based-on-a-conoscopic-holography-device-for-acquiring-surgical-surfaces
#8
Mikael Brudfors, Verónica García-Vázquez, Begoña Sesé-Lucio, Eugenio Marinetto, Manuel Desco, Javier Pascau
BACKGROUND: A difficulty in computer-assisted interventions is acquiring the patient's anatomy intraoperatively. Standard modalities have several limitations: low image quality (ultrasound), radiation exposure (computed tomography) or high costs (magnetic resonance imaging). An alternative approach uses a tracked pointer; however, the pointer causes tissue deformation and requires sterilizing. Recent proposals, utilizing a tracked conoscopic holography device, have shown promising results without the previously mentioned drawbacks...
November 21, 2016: International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS
https://www.readbyqxmd.com/read/27862910/dynamic-updating-atlas-for-heart-segmentation-with-a-nonlinear-field-based-model
#9
Ken Cai, Rongqian Yang, Hongwei Yue, Lihua Li, Shanxing Ou, Feng Liu
BACKGROUND: Segmentation of cardiac computed tomography (CT) images is an effective method for assessing the dynamic function of the heart and lungs. In the atlas-based heart segmentation approach, the quality of segmentation usually relies upon atlas images, and the selection of those reference images is a key step. The optimal goal in this selection process is to have the reference images as close to the target image as possible. METHODS: This study proposes an atlas dynamic update algorithm using a scheme of nonlinear deformation field...
November 9, 2016: International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS
https://www.readbyqxmd.com/read/27845913/bladder-accumulated-dose-in-image-guided-high-dose-rate-brachytherapy-for-locally-advanced-cervical-cancer-and-its-relation-to-urinary-toxicity
#10
Roja Zakariaee, Ghassan Hamarneh, Colin J Brown, Marc Gaudet, Christina Aquino-Parsons, Ingrid Spadinger
The purpose of this study was to estimate locally accumulated dose to the bladder in multi-fraction high-dose-date (HDR) image-guided intracavitary brachytherapy (IG-ICBT) for cervical cancer, and study the locally-accumulated dose parameters as predictors of late urinary toxicity. A retrospective study of 60 cervical cancer patients who received five HDR IG-ICBT sessions was performed. The bladder outer and inner surfaces were segmented for all sessions and a bladder-wall contour point-set was created in MATLAB...
December 21, 2016: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/27834643/visualization-of-deformable-image-registration-quality-using-local-image-dissimilarity
#11
Matthias Schlachter, Tobias Fechter, Miro Jurisic, Tanja Schimek-Jasch, Oliver Oehlke, Sonja Adebahr, Wolfgang Birkfellner, Ursula Nestle, Katja Bu Hler
Deformable image registration (DIR) has the potential to improve modern radiotherapy in many aspects, including volume definition, treatment planning and image-guided adaptive radiotherapy. Studies have shown its possible clinical benefits. However, measuring DIR accuracy is difficult without known ground truth, but necessary before integration in the radiotherapy workflow. Visual assessment is an important step towards clinical acceptance. We propose a visualization framework which supports the exploration and the assessment of DIR accuracy...
October 2016: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/27831867/real-time-ultrasound-segmentation-analysis-and-visualisation-of-deep-cervical-muscle-structure
#12
Ryan Cunningham, Peter Harding, Ian Loram
Despite widespread availability of ultrasound and a need for personalised muscle diagnosis (neck/back pain-injury, work related disorder, myopathies, neuropathies), robust, online segmentation of muscles within complex groups remains unsolved by existing methods. For example, Cervical Dystonia (CD) is a prevalent neurological condition causing painful spasticity in one or multiple muscles in the cervical muscle system. Clinicians currently have no method for targeting/monitoring treatment of deep muscles. Automated methods of muscle segmentation would enable clinicians to study, target, and monitor the deep cervical muscles via ultrasound...
November 1, 2016: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/27825795/an-mri-based-mid-ventilation-approach-for-radiotherapy-of-the-liver
#13
Tessa N van de Lindt, Gerald Schubert, Uulke A van der Heide, Jan-Jakob Sonke
MRI is increasingly being used in radiotherapy of the liver. The purpose of this study was to develop and validate a strategy to acquire MR images for treatment planning and image guidance in the presence of respiratory motion. By interleaving two navigator triggered MRI sequences, a fast but low-resolution image in mid-ventilation (midV) and a high-resolution image in exhale were acquired efficiently. Deformable registration was applied to map the exhale image to the midV anatomy. Cine-MRI scans were acquired for motion quantification...
November 2016: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/27824961/an-ultrasound-image-navigation-robotic-prostate-brachytherapy-system-based-on-us-to-mri-deformable-image-registration-method
#14
Shihui Zhang, Shan Jiang, Zhiyong Yang, Ranlu Liu, Yunpeng Yang, Honghua Liang
OBJECTIVE: This paper describes an ultrasound image navigation robotic prostate brachytherapy system. It uses a 2D ultrasound (US) probe rigidly fixed to a robotic needle insertion mechanism. Combined with the US probe registration and image registration, this system will help to navigate the prostate brachytherapy to increase the inserting accuracy. SUBJECTS AND METHODS: The novelty of the system is that after the US probe registration using an improved iterative closest point (ICP) registration method, the initial registration for the magnetic resonance imaging (MRI) and US image can be completely automatically...
November 8, 2016: Hellenic Journal of Nuclear Medicine
https://www.readbyqxmd.com/read/27823804/a-non-ionizing-technique-for-three-dimensional-measurement-of-the-lumbar-spine
#15
Terry K Koo, Wingchi Edmund Kwok
Comprehensive assessments of scoliotic deformity and spinal instability require repetitive three-dimensional (3D) measurements of motion segments at different functional postures. However, accurate 3D measurement of the spine is a challenging task. In this paper, we present a novel, non-invasive, non-ionizing technique to quantify 3D poses of lumbar motion segments in terms of clinically meaningful anatomical coordinates. The technique used ultra-short echo time (UTE) magnetic resonance (MR) images to construct subject-specific geometrical models of individual vertebrae and registered them with 3D ultrasound dataset acquired during pose measurements...
November 2, 2016: Journal of Biomechanics
https://www.readbyqxmd.com/read/27818606/modeling-4d-pathological-changes-by-leveraging-normative-models
#16
Bo Wang, Marcel Prastawa, Andrei Irimia, Avishek Saha, Wei Liu, S Y Matthew Goh, Paul M Vespa, John D Van Horn, Guido Gerig
With the increasing use of efficient multimodal 3D imaging, clinicians are able to access longitudinal imaging to stage pathological diseases, to monitor the efficacy of therapeutic interventions, or to assess and quantify rehabilitation efforts. Analysis of such four-dimensional (4D) image data presenting pathologies, including disappearing and newly appearing lesions, represents a significant challenge due to the presence of complex spatio-temporal changes. Image analysis methods for such 4D image data have to include not only a concept for joint segmentation of 3D datasets to account for inherent correlations of subject-specific repeated scans but also a mechanism to account for large deformations and the destruction and formation of lesions (e...
October 2016: Computer Vision and Image Understanding: CVIU
https://www.readbyqxmd.com/read/27816859/cross-contrast-multi-channel-image-registration-using-image-synthesis-for-mr-brain-images
#17
Min Chen, Aaron Carass, Amod Jog, Junghoon Lee, Snehashis Roy, Jerry L Prince
Multi-modal deformable registration is important for many medical image analysis tasks such as atlas alignment, image fusion, and distortion correction. Whereas a conventional method would register images with different modalities using modality independent features or information theoretic metrics such as mutual information, this paper presents a new framework that addresses the problem using a two-channel registration algorithm capable of using mono-modal similarity measures such as sum of squared differences or cross-correlation...
October 22, 2016: Medical Image Analysis
https://www.readbyqxmd.com/read/27811396/performance-evaluation-of-mind-demons-deformable-registration-of-mr-and-ct-images-in-spinal-interventions
#18
S Reaungamornrat, T De Silva, A Uneri, J Goerres, M Jacobson, M Ketcha, S Vogt, G Kleinszig, A J Khanna, J-P Wolinsky, J L Prince, J H Siewerdsen
Accurate intraoperative localization of target anatomy and adjacent nervous and vascular tissue is essential to safe, effective surgery, and multimodality deformable registration can be used to identify such anatomy by fusing preoperative CT or MR images with intraoperative images. A deformable image registration method has been developed to estimate viscoelastic diffeomorphisms between preoperative MR and intraoperative CT using modality-independent neighborhood descriptors (MIND) and a Huber metric for robust registration...
December 7, 2016: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/27796600/robust-augmented-reality-registration-method-for-localization-of-solid-organs-tumors-using-ct-derived-virtual-biomechanical-model-and-fluorescent-fiducials
#19
Seong-Ho Kong, Nazim Haouchine, Renato Soares, Andrey Klymchenko, Bohdan Andreiuk, Bruno Marques, Galyna Shabat, Thierry Piechaud, Michele Diana, Stéphane Cotin, Jacques Marescaux
BACKGROUND: Augmented reality (AR) is the fusion of computer-generated and real-time images. AR can be used in surgery as a navigation tool, by creating a patient-specific virtual model through 3D software manipulation of DICOM imaging (e.g., CT scan). The virtual model can be superimposed to real-time images enabling transparency visualization of internal anatomy and accurate localization of tumors. However, the 3D model is rigid and does not take into account inner structures' deformations...
October 27, 2016: Surgical Endoscopy
https://www.readbyqxmd.com/read/27788953/prospective-validation-of-a-high-dimensional-shape-model-for-organ-motion-in-intact-cervical-cancer
#20
Casey W Williamson, Garrett Green, Sonal S Noticewala, Nan Li, Hanjie Shen, Florin Vaida, Loren K Mell
PURPOSE: Validated models are needed to justify strategies to define planning target volumes (PTVs) for intact cervical cancer used in clinical practice. Our objective was to independently validate a previously published shape model, using data collected prospectively from clinical trials. METHODS AND MATERIALS: We analyzed 42 patients with intact cervical cancer treated with daily fractionated pelvic intensity modulated radiation therapy and concurrent chemotherapy in one of 2 prospective clinical trials...
November 15, 2016: International Journal of Radiation Oncology, Biology, Physics
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