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51. Defining cortical sulcus patterns using partial clustering based on bootstrap and bagging

Author

Fabrice Poupon, Edouard Duchesnay, Denis Rivière, Zhong Yi Sun, Bertrand Thirion, and J.-F. Mangin

Subjects
Atlas (topology), business.industry, Pattern recognition, Sulcus, Neurophysiology, Hierarchical clustering, Left cingulate sulcus, Open software, medicine.anatomical_structure, medicine, Artificial intelligence, Cluster analysis, business, Cortical sulcus, Mathematics
Abstract

The cortical folding patterns are very different from one individual to another. Here we try to find folding patterns automatically using large-scale datasets by non-supervised clustering analysis. The sulci of each brain are detected and identified using the brain VIS A open software. The 3D moment invariants are calculated and used as the shape descriptors of the sulci identified. A partial clustering algorithm using bootstrap sampling and bagging (PCBB) is devised for cortical pattern mining. Partial clusters are found using a modified hierarchical clustering method constrained by an objective function which looks for the most compact and dissimilar clusters. Bagging is used to increase stability. Experiments on simulated and real datasets are used to demonstrate the strength and stability of this algorithm compared to other standard approaches. Some cortical patterns are found using our method. In particular, the patterns found for the left cingulate sulcus are consistent with the patterns described in the atlas of Ono.

Published
2008
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52. Mean q-Ball Strings Obtained by Constrained Procrustes Analysis with Point Sliding

Author

Fabrice Poupon, Muriel Perrin, Irina Kezele, Jean-François Mangin, Yann Cointepas, Vincent El Kouby, and Cyril Poupon

Subjects
business.industry, Q-ball, Computer Science::Sound, Line (geometry), Outlier, Point (geometry), Computer vision, Artificial intelligence, Procrustes analysis, business, Focus (optics), Representation (mathematics), Algorithm, Mathematics, Resolution (algebra)
Abstract

The idea underpinning the work we present herein is to design robust and objective tools for brain white matter (WM) morphometry. We focus on WM tracts, and propose to represent them by their mean lines, to which we associate the attributes derived from high-angular resolution diffusion imaging (HARDI). The definition of the tract mean line derives directly from the geometry of the tract fibres. We determine the fibre point correspondences and impact factors of individual fibres, upon which we estimate average HARDI models along the tract mean lines. This way we obtain a compact tract representation that exploits all the available information, and is at the same time free of the outlier influence and undesired tract edge effects.

Published
2008
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53. Automatic Inference of Sulcus Patterns Using 3D Moment Invariants

Author

Jean Régis, Fabrice Poupon, Jean-François Mangin, Zhong Yi Sun, and Denis Rivière

Subjects
education.field_of_study, business.industry, Atlas (topology), Gaussian, Population, Pattern recognition, Sulcus, Hierarchical clustering, Open software, symbols.namesake, Compact space, medicine.anatomical_structure, Automatic inference, symbols, medicine, Artificial intelligence, business, education, Mathematics
Abstract

The goal of this work is the automatic inference of frequent patterns of the cortical sulci, namely patterns that can be observed only for a subset of the population. The sulci are detected and identified using brainVISA open software. Then, each sulcus is represented by a set of shape descriptors called the 3D moment invariants. Unsupervised agglomerative clustering is performed to define the patterns. A ratio between compactness and contrast among clusters is used to select the best patterns. A pattern is considered significant when this ratio is statistically better than the ratios obtained for clouds of points following a Gaussian distribution. The patterns inferred for the left cingulate sulcus are consistent with the patterns described in the atlas of Ono.

Published
2007
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54. Brain morphometry using 3D moment invariants

Author

D.L. Collins, Arnaud Cachia, Alan C. Evans, Edouard Duchesnay, Jean-François Mangin, Denis Rivière, Jean Régis, and Fabrice Poupon

Subjects
Male, Health Informatics, Models, Biological, Functional Laterality, Pattern Recognition, Automated, Imaging, Three-Dimensional, Image Interpretation, Computer-Assisted, Humans, Radiology, Nuclear Medicine and imaging, Computer vision, Computer Simulation, Invariant (mathematics), Mathematics, Cerebral Cortex, Radiological and Ultrasound Technology, business.industry, Brain morphometry, Pattern recognition, Computer Graphics and Computer-Aided Design, Magnetic Resonance Imaging, Principal component analysis, Female, Computer Vision and Pattern Recognition, Artificial intelligence, business, 3d coordinates, Algorithms
Abstract

This paper advocates the use of shape descriptors based on moments of 3D coordinates for morphometry of the cortical sulci. These descriptors, which have been introduced more than a decade ago, are invariant relatively to rotations, translations and scale and can be computed for any topology. A rapid insight into the derivation of these invariants is proposed first. Then, their potential to characterize shapes is shown from a principal component analysis of the 12 first invariants computed for 12 different deep brain structures manually drawn for 7 different brains. Finally, these invariants are used to find some correlates of handedness and sex among the shapes of 116 different cortical sulci automatically identified in each of 142 brains of the ICBM database.

Published
2004

55. Segmentation of the amygdalo-hippocampal complex by competitive region growing [MRI analysis]

Author

Sylvain Baillet, Fabrice Poupon, Dominique Hasboun, Marie Chupin, and Line Garnero

Subjects
Constraint (information theory), Quantitative Biology::Neurons and Cognition, Computer science, Segmentation-based object categorization, Region growing, business.industry, Scale-space segmentation, Computer vision, Segmentation, Image segmentation, Artificial intelligence, business
Abstract

Semi-automatic segmentation of amygdala and hippocampus is of major interest to neurologists but it is a challenge to numerical image analysis techniques because of intrinsic complexity of those structures. We introduce a new method to approach this problem with Markovian region growing. As we are concerned by segmenting atrophic structures, we did not use shape priors, but constrained the growth with relational and weak geometric priors. The major relational constraint is given by the simultaneous segmentation of hippocampus and amygdala. The algorithm runs quickly on a basic workstation with satisfactory results on both structures.

Published
2003
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56. Monitoring disease progression in CADASIL with diffusion magnetic resonance imaging: a study with whole brain histogram analysis

Author

Hugues Chabriat, Nicolas Molko, Sabina Pappatà, Jean-François Mangin, Fabrice Poupon, M.G. Bousser, Denis LeBihan, Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Cités, Territoires, Environnement et Sociétés (CITERES), Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), IFR de Neuroimagerie Fonctionnelle (IFR 49), Service de neurologie [Univ. Paris VII], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Lariboisière-Fernand-Widal [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7), Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT), Université Paris Diderot - Paris 7 (UPD7)-Hôpital Lariboisière-Fernand-Widal [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Université de Tours, Université de Tours-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Hôpital Lariboisière-Université Paris Diderot - Paris 7 (UPD7), and Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Male, Pathology, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Neuropsychological Tests, MESH: Regression Analysis, Diffusion, Leukoencephalopathy, Medicine, Longitudinal Studies, CADASIL, MESH: Longitudinal Studies, MESH: Receptors, Cell Surface, MESH: Aged, MESH: Middle Aged, medicine.diagnostic_test, Brain, MESH: Neuropsychological Tests, MESH: Diffusion, MESH: Follow-Up Studies, Middle Aged, MESH: Predictive Value of Tests, Predictive value of tests, Disease Progression, Regression Analysis, Female, MESH: Disease Progression, MESH: Dementia, Multi-Infarct, Cardiology and Cardiovascular Medicine, Adult, medicine.medical_specialty, Receptors, Cell Surface, MESH: Diffusion Magnetic Resonance Imaging, Sensitivity and Specificity, Central nervous system disease, MESH: Brain, MESH: Cross-Sectional Studies, Predictive Value of Tests, Proto-Oncogene Proteins, Humans, Aged, Advanced and Specialized Nursing, MESH: Humans, business.industry, Vascular disease, Magnetic resonance imaging, MESH: Adult, CADASIL Syndrome, medicine.disease, MESH: Male, MESH: Sensitivity and Specificity, MESH: Proto-Oncogene Proteins, Cross-Sectional Studies, Dementia, Multi-Infarct, Diffusion Magnetic Resonance Imaging, nervous system, Neurology (clinical), business, Nuclear medicine, MESH: Female, Follow-Up Studies, Diffusion MRI
Abstract

Background and Purpose— In cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a large increase in water diffusion has been found both inside and outside the cerebral lesions as detected on conventional MRI. The aim of the present study was to assess the sensitivity of diffusion tensor imaging for monitoring the progression of cerebral tissue damage during the course of CADASIL. Methods— With the use of diffusion tensor imaging, whole brain trace of the diffusion tensor [Trace(D)] histograms were obtained in 22 CADASIL patients and 12 age-matched controls at baseline, in 14 patients after a mean delay of 21 months, and in 5 controls after a mean delay of 29 months. Parameters derived from these histograms (mean value, peak height, and peak location) were analyzed at baseline and during the follow-up. Results— At baseline, all the histogram parameters differed between patients and controls and were found to be significantly correlated with both the Mini-Mental State Examination score and Rankin Scale score in the patient group. The follow-up study showed a decrease in the peak height associated with an increase in the mean value of whole brain Trace(D) histograms in the 14 CADASIL patients scanned twice. The diffusion changes appeared larger in the patients whose Rankin score increased during the study period. Conclusions— These results suggest that the measurement of water diffusion over time is a sensitive marker for the progression of tissue damage in the brain. Thus, quantitative diffusion MRI can be used to monitor disease progression in CADASIL and possibly in other types of small-vessel brain disorders.

Published
2002
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57. Role of the supplementary motor area in motor deficit following medial frontal lobe surgery

Author

Anne-Laure Boch, Laurent Capelle, Hugues Duffau, Stéphane Lehéricy, Claude Marsault, Charles-Ambroise Valery, Michaela Vlaicu, P. Cornu, J.-F. Mangin, D. Le Bihan, Alexandre Krainik, Fabrice Poupon, M. Sahel, Stéphane Clemenceau, Grenoble Institut des Neurosciences (GIN), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département de neuro-radiologie, Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble, Departement de neuroradiologie, CHU La Tronche, IFR de Neuroimagerie Fonctionnelle (IFR 49), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de Neuro-Imagerie de Recherche (CENIR), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), Neuro-anatomie fonctionnelle du comportement et de ses troubles, Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC), Hôpital Gui de Chauliac, Université Montpellier 1 (UM1)-Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Laboratoire de la Cognition et du Comportement, Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS), Département de neurochirurgie, Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Cités, Territoires, Environnement et Sociétés (CITERES), Centre National de la Recherche Scientifique (CNRS)-Université de Tours, Service de Neurochirurgie [CHU Pitié-Salpêtrière], CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Laboratoire d'Imagerie Fonctionnelle (LIF), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR14-IFR49-Institut National de la Santé et de la Recherche Médicale (INSERM), Cortex et Epilepsie [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Service Hospitalier Frédéric Joliot (SHFJ), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Service NEUROSPIN (NEUROSPIN), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT), Grenoble Institut des Neurosciences ( GIN ), Institut National de la Santé et de la Recherche Médicale ( INSERM ) -CHU Grenoble-Université Joseph Fourier - Grenoble 1 ( UJF ), Université Joseph Fourier - Grenoble 1 ( UJF ) -CHU Grenoble, IFR de Neuroimagerie Fonctionnelle ( IFR 49 ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Centre de Neuro-Imagerie de Recherche ( CENIR ), Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Pitié-Salpêtrière [APHP], Institut National de la Santé et de la Recherche Médicale ( INSERM ) -IFR70-Université Pierre et Marie Curie - Paris 6 ( UPMC ), Université Montpellier 1 ( UM1 ) -Centre Hospitalier Régional Universitaire [Montpellier] ( CHRU Montpellier ), Université Paris Descartes - Paris 5 ( UPD5 ) -Centre National de la Recherche Scientifique ( CNRS ), Centre Hospitalier Régional Universitaire [Montpellier] ( CHRU Montpellier ), Cités, Territoires, Environnement et Sociétés ( CITERES ), Université de Tours-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Imagerie Fonctionnelle ( LIF ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -IFR14-IFR49-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -CHU Pitié-Salpêtrière [APHP], Department of Neurosurgery, Assistance publique - Hôpitaux de Paris (AP-HP), Laboratoire de Neuroimagerie Assistée par Ordinateur ( LNAO ), Service Hospitalier Frédéric Joliot ( SHFJ ), Direction de Recherche Fondamentale (CEA) ( DRF (CEA) ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Service NEUROSPIN ( NEUROSPIN ), Center for NeuroImaging Research-Human MRI Neuroimaging core facility for clinical research [ICM Paris] (CENIR), Institut du Cerveau = Paris Brain Institute (ICM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Hôpital Gui de Chauliac [CHU Montpellier], Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Grenoble-Université Joseph Fourier - Grenoble 1 (UJF), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-CHU Pitié-Salpêtrière [APHP], Université de Tours-Centre National de la Recherche Scientifique (CNRS), CHU Pitié-Salpêtrière [APHP]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)

Subjects
Male, MESH : Retrospective Studies, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH : Aged, MESH: Frontal Lobe, Neurological disorder, 030218 nuclear medicine & medical imaging, MESH: Magnetic Resonance Imaging, Postoperative Complications, 0302 clinical medicine, MESH: Postoperative Complications, [ SDV.IB.IMA ] Life Sciences [q-bio]/Bioengineering/Imaging, MESH: Aged, MESH: Middle Aged, Supplementary motor area, medicine.diagnostic_test, Brain Neoplasms, Motor Cortex, MESH : Adult, MESH : Motor Cortex, Middle Aged, SMA, Magnetic Resonance Imaging, Frontal Lobe, Motor Skills Disorders, medicine.anatomical_structure, Frontal lobe, MESH : Motor Skills Disorders, MESH: Brain Neoplasms, Psychology, MESH: Motor Skills Disorders, Adult, medicine.medical_specialty, Spontaneous movements, MESH : Male, MESH: Motor Cortex, 03 medical and health sciences, MESH : Magnetic Resonance Imaging, medicine, MESH : Frontal Lobe, Humans, MESH : Middle Aged, MESH : Brain Neoplasms, Aged, Retrospective Studies, MESH: Humans, MESH : Humans, Magnetic resonance imaging, Retrospective cohort study, MESH: Adult, MESH: Retrospective Studies, medicine.disease, MESH: Male, Surgery, MESH : Postoperative Complications, Neurology (clinical), Motor Deficit, 030217 neurology & neurosurgery
Abstract

International audience; OBJECTIVE: Patients undergoing surgical resection of medial frontal lesions may present a transient postoperative deficit that remains largely unpredictable. The authors studied the role of the supplementary motor area (SMA) in the occurrence of this deficit using fMRI. METHODS: Twenty-three patients underwent a preoperative fMRI before resection of medial frontal lesions. Tasks included self-paced flexion/extension of the left and right hand, successively. Preoperative fMRI data were compared with postoperative MRI data and with neurologic outcome. RESULTS: Following surgery, 11 patients had a motor deficit from which all patients recovered within a few weeks or months. The deficit was similar across patients, consisting of a global reduction in spontaneous movements contralateral to the operated side with variable severity. SMA activation was observed in all patients. The deficit was observed when the area activated in the posterior part of the SMA (SMA proper) was resected. CONCLUSIONS: fMRI is able to identify the area at risk in the SMA proper whose resection is highly related to the occurrence of the motor deficit. The clinical characteristics of this deficit support the role of the SMA proper in the initiation and execution of the movement.

Published
2001

58. Clinical severity in CADASIL related to ultrastructural damage in white matter: in vivo study with diffusion tensor MRI

Author

M. Pachot-Clouard, Hugues Chabriat, Chris A. Clark, Sabina Pappatà, Cyril Poupon, Marie-Germaine Bousser, Fabrice Poupon, Katayoun Vahedi, D. Le Bihan, J.-F. Mangin, Antoinette Jobert, Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Imagerie et de Spectroscopie (LRMN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Cités, Territoires, Environnement et Sociétés (CITERES), Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Neuroimagerie Assistée par Ordinateur (LNAO), Center for Neuroscience and Behavioral Medicine, Children's National Medical Center, Neuroimagerie Fonctionnelle et Metabolique, Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM), IFR de Neuroimagerie Fonctionnelle (IFR 49), Institutions et Dynamiques Historiques de l'Economie (IDHE), École normale supérieure - Cachan (ENS Cachan)-Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Service de neurologie [Univ. Paris VII], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Lariboisière-Fernand-Widal [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7), Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT), Université Paris Diderot - Paris 7 (UPD7)-Hôpital Lariboisière-Fernand-Widal [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université de Tours-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Cachan (ENS Cachan)-Université Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-Hôpital Lariboisière-Université Paris Diderot - Paris 7 (UPD7), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université de Tours

Subjects
Adult, Pathology, medicine.medical_specialty, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, MESH: Magnetic Resonance Imaging, Leukoencephalopathy, White matter, Diffusion, MESH: Brain, MESH: Analysis of Variance, Centrum semiovale, medicine, Humans, CADASIL, MESH: Brain Mapping, Aged, Advanced and Specialized Nursing, MESH: Aged, Analysis of Variance, Brain Mapping, MESH: Middle Aged, MESH: Humans, medicine.diagnostic_test, business.industry, Brain, Magnetic resonance imaging, MESH: Adult, MESH: Diffusion, CADASIL Syndrome, Middle Aged, medicine.disease, Magnetic Resonance Imaging, MESH: Case-Control Studies, Hyperintensity, MESH: Extracellular Space, medicine.anatomical_structure, Dementia, Multi-Infarct, Case-Control Studies, Neurology (clinical), MESH: Dementia, Multi-Infarct, Cardiology and Cardiovascular Medicine, business, Extracellular Space, Diffusion MRI
Abstract

Background and Purpose —CADASIL is a newly recognized cause of subcortical ischemic strokes that progressively leads to dementia associated with pseudobulbar palsy and severe motor disability. This deleterious progression and the severity of clinical presentation are widely variable among affected subjects. The exact role played by MRI white-matter abnormalities, a hallmark of the disease, in the severity of the clinical phenotype remains poorly understood. Methods —To address this issue, we used diffusion tensor imaging (DTI), a new MRI technique highly sensitive to white-matter microstructural changes, in 16 symptomatic patients and 10 age-matched controls. Mean diffusivity and anisotropy of diffusion were measured within hyperintensities identified on T2-weighted images (T2WI) and outside these lesions on 4 slices at the level of centrum semiovale. Results —We found a 60% increase of water mean diffusivity and a parallel loss of diffusion anisotropy in hyperintensities identified on T2WI. The same pattern of diffusion changes, but of lesser intensity, was found in the normal-appearing white matter on T2WI. Mean diffusivity in regions with increased signal on T2WI was higher in patients with severe clinical disability compared with those with no or mild deficit (1.33±0.11 versus 1.13±0.11 10 −3 mm 2 /s, P Conclusions —These results indicate that DTI is able to detect important ultrastructural changes in regions with increased signal on T2WI and within the normal-appearing white matter in CADASIL. The diffusion changes might be related to both neuronal loss and demyelination. The degree of the underlying ultrastructural alterations is related to the severity of the clinical status with a possible threshold level of white-matter damage above which severe neurological impairment may occur in this disease. DTI appears to be a promising technique for monitoring disease progression in CADASIL.

Published
1999

59. Multi-object deformable templates dedicated to the segmentation of brain deep structures

Author

Dominique Hasboun, C. Poupon, Jean-François Mangin, Isabelle E. Magnin, Vincent Frouin, and Fabrice Poupon

Subjects
Moment (mathematics), Template, Computer science, business.industry, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Process (computing), Initialization, Embedding, Computer vision, Segmentation, Artificial intelligence, Object (computer science), business
Abstract

We propose a new way of embedding shape distributions in a topological deformable template. These distributions rely on global shape descriptors corresponding to the 3D moment invariants. In opposition to usual Fourier-like descriptors, they can be updated during deformations at a relatively low cost. The moment-based distributions are included in a framework allowing the management of several simultaneously deforming objects. This framework is dedicated to the segmentation of brain deep nuclei in 3D MR images. The paper focuses on the learning of the shape distributions, on the initialization of the topological model and on the multi-resolution energy minimization process. Results are presented showing the segmentation of twelve brain deep structures.

Published
1998
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60. Regularization of MR diffusion tensor maps for tracking brain white matter bundles

Author

Isabelle Bloch, D. Le Bihan, Vincent Frouin, Jean Régis, Fabrice Poupon, M. Pachot-Clouard, Cyril Poupon, and Jean-François Mangin

Subjects
White matter, medicine.anatomical_structure, medicine, Diffusion map, Fiber bundle, Tensor, Diffusion (business), Topology, Tracking (particle physics), Regularization (mathematics), Algorithm, Mathematics, Diffusion MRI
Abstract

We propose a new way for tracking brain white matter fiber bundles in diffusion tensor maps. Diffusion maps provide information about mobility of water protons in different directions. Assuming that diffusion is more important along axons, this information could lead to the direction of fiber bundles in white matter. Nevertheless, protocoles for diffusion image acquisition suffer from low resolutions and instrument noise. This paper is essentially dedicated to the design of a Markovian model aiming at the regularization of direction maps, and at the tracking of fiber bundles. Results are presented on synthetic tensor images to confirm the efficiency of the method. Then, white matter regions are regularized in order to enable the tracking of fiber bundles, which is of increasing interest in functional connectivity studies.

Published
1998
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61. Atlas-based analysis of human brainstem anatomy as revealed by gradient-echo T2*-weighted MR imaging at 7T

Author

Stéphane Lehéricy, Fabrice Poupon, L. Marrakchi, Jérôme Yelnik, P-F. van de Moortele, S. Fernandez-Vidal, C. Poupon, K. Ugurbil, I. Kezele, Eric Bardinet, Dominique Hasboun, and J-F Mangin

Subjects
Physics, Midbrain, Subthalamic nucleus, Neurology, Atlas (topology), Red nucleus, Cognitive Neuroscience, Substantia nigra, Segmentation, Brainstem, Anatomy, Pedunculopontine nucleus
Abstract

Introduction Spatial MR image resolution improved drastically with appearance of ultra-high field MR systems. Moreover, new contrasts based on iron concentration in deep nuclei emerged. Iron deposition results in signal drop in T2*-weighted images on high-field systems which helps the segmentation of some mesencephalon structures (e.g. substantia nigra, red nucleus, and subthalamic nucleus) that cannot be well delineated at lower field. This is of a great interest in Parkinson’s disease studies where pathological alterations of the aforementioned structures are observed [1, 2]. Nonetheless, for a variant of Parkinson disease some other smaller structures of the brainstem are also involved (e.g. pedunculopontine nucleus PPN) but they cannot be distinguished even with high resolution images at 7T. We have thus analyzed a gradient echo T2-weighted MR acquisition with the help of two different atlases: 1) a 3D histological [3] and deformable [4] atlas, which comprises several nuclei and fiber bundles of the mesencephalon, 2) a printed histological atlas of the entire brainstem [5] that we have numerized and reconstructed for this study.

Published
2009
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62. A structural browser for human brain mapping

Author

Vincent Frouin, Olivier Coulon, Jean-Baptiste Poline, Denis Rivière, Cyril Poupon, Fabrice Poupon, Jean-François Mangin, Jean Régis, and Dimitri Papadopoulos

Subjects
Neurology, Computer science, Cognitive Neuroscience, Human brain mapping, Neuroscience
Published
2000
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63. Tracking fiber bundles in diffusion tensor images

Author

J.-F. Mangin, Isabelle Bloch, Jean Régis, Denis LeBihan, Vincent Frouin, C. Poupon, Fabrice Poupon, and M. Pachot-Clouart

Subjects
Physics, Optics, Neurology, business.industry, Cognitive Neuroscience, Fiber bundle, business, Tracking (particle physics), Diffusion MRI
Published
1998
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64. Real-time MR diffusion tensor and Q-Ball imaging using Kalman filtering

Author

C. Poupon, Y. Cointepas, Alexis Roche, Fabrice Poupon, J.-F. Mangin, and Jessica Dubois

Subjects
Q-ball, Orientation (computer vision), business.industry, Tensor (intrinsic definition), Magnet, Fast Kalman filter, Computer vision, Kalman filter, Artificial intelligence, Diffusion (business), business, Diffusion MRI, Mathematics
Abstract

Magnetic resonance diffusion imaging (dMRI) has become an established research tool for the investigation of tissue structure and orientation. In this paper, we present a method for real time processing of diffusion tensor and Q-ball imaging. The basic idea is to use Kalman filtering framework to fit either the linear tensor or Q-ball model. Because the Kalman filter is designed to be an incremental algorithm, it naturally enables updating the model estimate after the acquisition of any new diffusion-weighted volume. Processing diffusion models and maps during ongoing scans provides a new useful tool for clinicians, especially when it is not possible to predict how long a subject may remain still in the magnet.

65. 3D moment invariant based morphometry

Author

Alan C. Evans, Jean Régis, Fabrice Poupon, D. Rivière, J.-F. Mangin, Arnaud Cachia, and D. L. Collins

Subjects
Shape space, Quantitative Biology::Neurons and Cognition, business.industry, Principal component analysis, Central moment, Pattern recognition, Artificial intelligence, Invariant (mathematics), business, Central sulcus, 3d coordinates, Mathematics
Abstract

This paper advocates the use of shape descriptors based on moments of 3D coordinates for morphometry of the cortical sulci. These descriptors, which have been introduced more than a decade ago, are invariant relatively to rotations, symmetry and scale and can be computed for any topology. A rapid insight of the derivation of these invariants is proposed first. Then, their potential to characterize shapes is shown from a principal component analysis of the 12 first invariants computed for 12 different deep brain structures manually drawn from 7 different brains. Finally, these invariants are used to find some correlates of handedness among the shapes of 116 different cortical sulci automatically identified in 144 brains of the ICBM database.

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