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Registration of Three Dimensional Medical Images QUT Digital Repository: http://eprints.qut.edu.au/ Fookes, Clinton B. and Bennamoun, Mohammed (2000) Registration of three dimensional medical images. © Copyright 2000 Queensland University of Technology Registration of Three Dimensional Medical Images Clinton Fo okes and Mohammed Bennamoun Technical Rep ort Space Centre for Satellite Navigation Scho ol of Electrical and Electronic Systems Engineering Queensland University of Technology GPO Box Qld Australia July c Space Centre for Satellite Navigation Further repro duction prohibited ISBN Copyright Disclaimer Every attempt has b een made to contact the copyright owners of material presented in this rep ort Unfortunately in some cases this has not b een p ossible and the authors would welcome contact from these owners i Abstract Image registration is a fundamental problem that can b e found in a diverse range of elds within the research community It is used in areas such as engineering science medicine rob otics computer vision and image pro cessing which often require the pro cess of developing a spatial mapping b etween sets of data In the eld of medical imaging image registration is required to match images acquired from various imag ing mo dalities Recent advances in these imaging mo dalities including MRI CTI and PET now allow the generation of D images that explicitly outline detailed in vivo information of not only human anatomy but also metab olic function The amount of time and eort dedicated to the research of medical image registration is a testimony to the imp ortance and signicance that this area holds in the medical eld This has consequently lead to the development of new and fascinating opp ortunities for areas involving diagnosis and therapy This includes applications such as surgical planning image guided surgery and surgery simulation However the creation of such opp ortunities would not have b een p ossible without the enormous advances made in computing technology which is required in order to facilitate ecient D image regis tration A common task within medical image registration is the fusing of the complimentary and synergistic information provided by the various imaging mo dalities This pro cess is known as multimo dal registration Another common task is in the registration of images of the same patient taken at dierent times andor in dierent p ositions This pro cess is referred to as monomo dal registration and can b e used to track any pathological evolution Other applications include interpatient registration and registration of a patients scan with an anatomical atlas The latter application is extremely useful for further applications such as the statistical analysis of p opulations and automatic segmentation In a quest to further understand some of the inherent advantages and disadvantages of image registration algorithms a literature review was undertaken A classication of ii registration algorithms was also presented along with the literature review This clas sication scheme is based on certain characteristics that a registration algorithm may exhibit The categories include the algorithms dimensionality nature of the registra tion algorithm nature and domain of the transformation user interaction optimisation pro cedure mo dalities involved and the typ e of sub ject and ob jects involved in the reg istration pro cess Traditional registration metho ds were based on either manual metho ds or the use of ducial markers These metho ds either pro duced a p o or accuracy or a greater accuracy obtained at the exp ense of patient comfort There has since b een a global trend towards the development of retrosp ective registration metho ds that are noninvasive The bulk of these develop ed techniques are based on intrinsic metho ds that only utilise the in herent information contained in a patients image Surfacebased and intensitybased techniques are currently the most p opular form of intrinsic metho ds where the latter is slowly setting the standard for registration accuracy From the literature review it was found that surfacebased registration metho ds are currently used the most in clinical applications This is due to the slight sp eed ad vantage that they have over intensitybased metho ds However one of the drawbacks of surface based metho ds is that they cannot handle cases when the surfaces b eing matched signicantly dier from each other To overcome such problems requires the use of nonrigid registration techniques However more research is required into these approaches as the complexity involved is still to o high to eectively utilise them in realtime applications This research aims to further develop noninvasive retrosp ective registration techniques that are more accurate robust and fully automatic This rep ort presents a thorough intro duction into the eld of medical image registration It includes background on the various imaging mo dalities a lo ok at some relevant applications of registration a classication of registration algorithms and a literature review on sp ecic techniques The rep ort is then nished with a conclusion and a discussion on some future directions of registration iii Contents Abstract ii Intro duction What is Registration Motivation Scop e of the rep ort Medical Imaging Mo dalities CTI Computed Tomography Imaging MRI Magnetic Resonance Imaging PET Positron Emission Tomography Other Imaging Mo dalities Related Issues Applications Computer Integrated Surgery and Therapy Ob jectives of Computer Integrated Surgery and Therapy Other applications iv CONTENTS CONTENTS Classication of Registration Techniques Dimensionality D D D Registration involving Spatial Dimensions Registration of Time Series Nature of the Registration Algorithm Extrinsic Metho ds Intrinsic Metho ds NonImage Based Metho ds Nature Domain of the Transformation Nature of the Transformation Domain of the Transformation Related Issues Regarding the Transformation Interaction Optimisation Pro cedure Mo dalities Involved Sub ject Ob ject Validation and Related Issues Literature Survey The Mathematics of Registration Point Techniques Registration with p oint corresp ondences Registration without p oint corresp ondences Extremal Points Curve Techniques v CONTENTS CONTENTS Marching Lines Algorithm Surface Techniques The Head Hat Algorithm Hierarchical Chamfer Matching The Iterative Closet Point Algorithm Intensity Based Techniques Moments and Principal Axis Techniques Correlation Grey Level Co o ccurence Matrices Mutual Information NonRigid Registration Techniques Deformable Mo dels Physical Continuum Mo dels Discussions and Conclussion Bibliography vi List of Figures Light b ox showing many crosssections of a Patients MRI scan Example CT scanner layout Example picture of a CT image Two MRI images Left MR T weighted Right MR proton density weighted Each submo dality represents the same image but in slightly dierent intensity values Example PET image Dierent intensity values represent dierent levels of brain funciton Relationship b etween the medical imaging systems Repro duced with p ermission of authors Three MRI slices in the transverse coronal and sagittal planes resp ectively CIST metho dology p erception decision action Lo op Repro duced with p ermission of authors Hepatic surgery simulation Repro duced with p ermission of owners co Epidaure Research Pro ject INRIA httpwwwsopinriafrepidaure Anatomical mo del of a skull Repro duced with p ermission of owners co Anatomics The Biomo delling Sp ecialists httpwwwanatomicscomau A taxonomy for the classication of registration algorithms Examples of rigid ane pro jective and curved D transformations in b oth the global and lo cal domain vii LIST OF FIGURES LIST OF FIGURES Examples of registering an ob ject according to rigid elastic and free deformation motion Matching two dierent brains using b oth rigid and nonrigid matching Multiresolution registration technique Registered MRIPET images This allows functional information to b e viewed in the context of anatomical information Preop erative image registered to a video image of a patient Repro
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