Begell House Inc.
Critical Reviews™ in Biomedical Engineering
CRB
0278-940X
40
2
2012
Preface: Detection, Modeling, and Compensation of Organ Motion and Deformation−Part I
97-98
10.1615/CritRevBiomedEng.v40.i2.10
Tobias
Preusser
Fraunhofer MEVIS; and School of Engineering and Science, Jacobs University, Bremen, Germany
Matthias
Gunther
Fraunhofer MEVIS, Institute for Medical Image Computing Bremen; Fachbereich 1 (Physik/Elektrotechnik), Universität Bremen, Bremen, Germany
Horst Karl
Hahn
Fraunhofer MEVIS, Institute for Medical Image Computing Bremen
Motion Compensation Strategies in Magnetic Resonance Imaging
99-119
10.1615/CritRevBiomedEng.v40.i2.20
Ruud B.
van Heeswijk
Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
Gabriele
Bonanno
Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
Simone
Coppo
Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
Andrew
Coristine
Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
Tobias
Kober
Advanced Clinical Imaging Technology, Siemens Healthcare Sector IM&WS S, Lausanne, Switzerland
Matthias
Stuber
Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
magnetic resonance imaging
motion correction
gating
triggering
navigators
Image quality in magnetic resonance imaging (MRI) is considerably affected by motion. Therefore, motion is one of the most common sources of artifacts in contemporary cardiovascular MRI. Such artifacts in turn may easily lead to misinterpretations in the images and a subsequent loss in diagnostic quality. Hence, there is considerable research interest in strategies that help to overcome these limitations at minimal cost in time, spatial resolution, temporal resolution, and signal-to-noise ratio. This review summarizes and discusses the three principal sources of motion: the beating heart, the breathing lungs, and bulk patient movement. This is followed by a comprehensive overview of commonly used compensation strategies for these different types of motion. Finally, a summary and an outlook are provided.
Magnetic Resonance− and Ultrasound Imaging−Based Elasticity Imaging Methods: A Review
121-134
10.1615/CritRevBiomedEng.v40.i2.30
Jonathan
Vappou
Fluid and Solid Mechanics Institute, FRE 3240 and Image Sciences, Computer Sciences and Remote Sensing Laboratory (LSIIT), UMR 7005, Strasbourg University-CNRS, Strasbourg, France
noninvasive testing
biomechanics and biomechanical testing
viscoelasticity
ultrasound elastography
magnetic resonance elastography (MRE)
Elasticity imaging methods aim at measuring the mechanical behavior of soft tissues by using medical imaging modalities, such as ultrasonography or magnetic resonance imaging. The initial motivation behind these techniques, and still the main one, is the need for new diagnostic tools based on the visualization of tissue stiffness. Recent developments have demonstrated the potential that elasticity imaging methods can offer in new fields other than direct medical diagnosis, such as the field of in vivo biomechanical characterization. After a short description of the general principles behind elasticity imaging, this review illustrates some of the most original clinical applications. The use of elastography for quantitative mechanical characterization is particularly emphasized, and original applications of these methods to several biomedical research fields are reviewed.
Review on 4D Models for Organ Motion Compensation
135-154
10.1615/CritRevBiomedEng.v40.i2.40
Christine
Tanner
Computer Vision Laboratory, ETH Zurich, Switzerland
Dirk
Boye
Computer Vision Laboratory, ETH Zurich, Switzerland; Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
Golnoosh
Samei
Computer Vision Laboratory, ETH Zurich, Switzerland
Gabor
Szekely
Computer Vision Laboratory, ETH Zurich, Switzerland
4D motion model
motion compensation
prediction
respiratory motion
tumor therapy
review
Minimal invasive tumor therapies are getting ever more sophisticated with novel treatment approaches and new devices allowing for improved targeting precision. Applying these effectively requires precise localization of the structures of interest. Vital processes, such as respiration and heartbeat, induce organ motion, which cannot be neglected during therapy. This review focuses on 4D organ models to compensate for respiratory motion during therapy. An overview is given on the effects of motion on the therapeutical outcome, methods required to capture and quantify respiratory motion, range of reported tumor motion, types of surrogates used when tumors are not directly observable, and methods for temporal prediction of surrogate motion. Organ motion models, which predict the location of structures of interest from surrogates measured during therapy, are discussed in detail.
Efficient Finite Element Methods for Deformable Bodies in Medical Applications
155-172
10.1615/CritRevBiomedEng.v40.i2.50
Joachim
Georgii
Fraunhofer MEVIS, Institute for Medical Image Computing, Bremen, Germany
Christian
Dick
Computer Graphics & Visualization Group, Technische Universitat Munchen, Germany
deformable bodies
corotated finite elements
graphics processing units
Simulation techniques for deformable bodies are of major relevance for a broad range of medical applications. In recent decades, a lot of work has been performed to improve simulation methods, allowing interactivity or even real time. However, this work often focused on applications such as computer games or virtual environments, where physical accuracy is not a primary goal. The goal of this report is to give an overview of efficient physics-based techniques for deformable objects, focusing on finite element methods, and to discuss the applicability of these techniques in medical scenarios. As a result, we focus on techniques that are amenable to simulating highly resolved meshes, which for instance can be generated from computed tomography (CT) or magnetic resonance (MR) images, and we review the so-called corotated finite element method that has shown a high potential in recent years. Specifically, we will capture in detail the related work in this field and demonstrate the current state of the art in efficient deformable bodies simulations.