Slide 1
An Anatomically Curated Fiber Clustering White Matter Atlas for Consistent White Matter Tract Parcellation across the Lifespan
Slide 2
An Immersive Virtual Reality Environment for Diagnostic Imaging
Slide 3
Inter-site and Inter-scanner Diffusion MRI Data Harmonization
Slide 4
The Open Anatomy Browser: A Collaborative Web-Based Viewer for Interoperable Anatomy Atlases
Slide 5
Unsupervised Discovery of Emphysema Subtypes in a Large Clinical Cohort
Slide 6
Identifying Shared Brain Networks in Individuals by Decoupling Functional and Anatomical Variability
Slide 7
Supra-Threshold Fiber Cluster Statistics for Data-Driven Whole Brain Tractography Analysis
Slide 8
Free Water Modeling of Peritumoral Edema using Multi-fiber Tractography
Slide 8
Estimation of Bounded and Unbounded Trajectories in Diffusion MRI
Slide 9
Principal Gradient of Macroscale Cortical Organization
Slide 10
Evolution of a Simultaneous Segmentation and Atlas Registration
Slide 11
Multi-modality MRI-based Atlas of the Brain
Slide 12
Intracranial Fluid Redistribution
Slide 13
Corticospinal Tract Modeling for Neurosurgical Planning by Tracking through Regions of Peritumoral Edema and Crossing Fibers
Slide 14
Automated White Matter Fiber Tract Identification in Patients with Brain Tumors
Slide 15
State-space Models of Mental Processes from fMRI
Slide 16
Robust Initialization of Active Shape Models for Lung Segmentation in CT Scans: A Feature-Based Atlas Approach
Slide 17
Tractography-driven Groupwise Multi-Scale Parcellation of the Cortex
Slide 18
Gray Matter Alterations in Early Aging
Slide 19
Statistical Shape Analysis: From Landmarks to Diffeomorphisms
Slide 20
A Generative Probabilistic Model and Discriminative Extensions for Brain Lesion Segmentation
Slide 21
Joint Modeling of Imaging and Genetic Variability
Slide 22
MR-Ultrasound Fusion for Neurosurgery
Slide 23
Diffusion MRI and Tumor Heterogeneity
Slide 24
SlicerDMRI: Open Source Diffusion MRI Software for Brain Cancer Research

Neuroimage Analysis Center

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The Neuroimaging Analysis Center is a research and technology center with the mission of advancing the role of neuroimaging in health care. The ability to access huge cohorts of patient medical records and radiology data, the emergence of ever-more detailed imaging modalities, and the availability of unprecedented computer processing power marks the possibility for a new era in neuroimaging, disease understanding, and patient treatment. We are excited to present a national resource center with the goal of finding new ways of extracting disease characteristics from advanced imaging and computation, and to make these methods available to the larger medical community through a proven methodology of world-class research, open-source software, and extensive collaboration.

Our Sponsor

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NIBIB

The NAC is a Biomedical Technology Resource Center supported by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) (P41 EB015902). It was supported by the National Center for Research Resources (NCRR) (P41 RR13218) through December 2011.

Contact the Center Directors

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Westin

Carl-Fredrik Westin, PhD
Laboratory of Mathematics in Imaging
Brigham and Women's Hospital
1249 Boylston St., Room 240
Boston, MA 02215
Phone: +1 617 525-6209
E-mail: westin at bwh.harvard.edu
 

Ron Kikinis

Ron Kikinis, MD
Surgical Planning Laboratory 
Brigham and Women's Hospital 
75 Francis St, L1 Room 050
Boston, MA 02115
Phone: +1 617 732-7389
E-mail: kikinis at bwh.harvard.edu
 

 

Recent Publications

  • Färneback G, Westin C-F. Affine and deformable registration based on polynomial expansion. Med Image Comput Comput Assist Interv 2006;9(Pt 1):857-64.
    This paper presents a registration framework based on the polynomial expansion transform. The idea of polynomial expansion is that the image is locally approximated by polynomials at each pixel. Starting with observations of how the coefficients of ideal linear and quadratic polynomials change under translation and affine transformation, algorithms are developed to estimate translation and compute affine and deformable registration between a fixed and a moving image, from the polynomial expansion coefficients. All algorithms can be used for signals of any dimensionality. The algorithms are evaluated on medical data.
  • Nain D, Haker S, Bobick A, Tannenbaum A. Shape-driven 3D segmentation using spherical wavelets. Med Image Comput Comput Assist Interv 2006;9(Pt 1):66-74.
    This paper presents a novel active surface segmentation algorithm using a multiscale shape representation and prior. We define a parametric model of a surface using spherical wavelet functions and learn a prior probability distribution over the wavelet coefficients to model shape variations at different scales and spatial locations in a training set. Based on this representation, we derive a parametric active surface evolution using the multiscale prior coefficients as parameters for our optimization procedure to naturally include the prior in the segmentation framework. Additionally, the optimization method can be applied in a coarse-to-fine manner. We apply our algorithm to the segmentation of brain caudate nucleus, of interest in the study of schizophrenia. Our validation shows our algorithm is computationally efficient and outperforms the Active Shape Model algorithm by capturing finer shape details.
  • Warfield SK, Zou KH, Wells WM. Validation of Image Segmentation by Estimating Rater Bias and Variance. Med Image Comput Comput Assist Interv 2006;9(Pt 2):839-47.
    The accuracy and precision of segmentations of medical images has been difficult to quantify in the absence of a "ground truth" or reference standard segmentation for clinical data. Although physical or digital phantoms can help by providing a reference standard, they do not allow the reproduction of the full range of imaging and anatomical characteristics observed in clinical data. An alternative assessment approach is to compare to segmentations generated by domain experts. Segmentations may be generated by raters who are trained experts or by automated image analysis algorithms. Typically these segmentations differ due to intra-rater and inter-rater variability. The most appropriate way to compare such segmentations has been unclear. We present here a new algorithm to enable the estimation of performance characteristics, and a true labeling, from observations of segmentations of imaging data where segmentation labels may be ordered or continuous measures. This approach may be used with, amongst others, surface, distance transform or level set representations of segmentations, and can be used to assess whether or not a rater consistently over-estimates or under-estimates the position of a boundary.
  • Pohl KM, Fisher J, Shenton M, McCarley RW, Grimson EL, Kikinis R, Wells WM. Logarithm odds maps for shape representation. Med Image Comput Comput Assist Interv 2006;9(Pt 2):955-63.
    The concept of the Logarithm of the Odds (LogOdds) is frequently used in areas such as artificial neural networks, economics, and biology. Here, we utilize LogOdds for a shape representation that demonstrates desirable properties for medical imaging. For example, the representation encodes the shape of an anatomical structure as well as the variations within that structure. These variations are embedded in a vector space that relates to a probabilistic model. We apply our representation to a voxel based segmentation algorithm. We do so by embedding the manifold of Signed Distance Maps (SDM) into the linear space of LogOdds. The LogOdds variant is superior to the SDM model in an experiment segmenting 20 subjects into subcortical structures. We also use LogOdds in the non-convex interpolation between space conditioned distributions. We apply this model to a longitudinal schizophrenia study using quadratic splines. The resulting time-continuous simulation of the schizophrenic aging process has a higher accuracy then a model based on convex interpolation.
  • Ziyan U, Tuch D, Westin C-F. Segmentation of thalamic nuclei from DTI using spectral clustering. Med Image Comput Comput Assist Interv 2006;9(Pt 2):807-14.
    Recent work shows that diffusion tensor imaging (DTI) can help resolving thalamic nuclei based on the characteristic fiber orientation of the corticothalamic/thalamocortical striations within each nucleus. In this paper we describe a novel segmentation method based on spectral clustering. We use Markovian relaxation to handle spatial information in a natural way, and we explicitly minimize the normalized cut criteria of the spectral clustering for a better optimization. Using this modified spectral clustering algorithm, we can resolve the organization of the thalamic nuclei into groups and subgroups solely based on the voxel affinity matrix, avoiding the need for explicitly defined cluster centers. The identification of nuclear subdivisions can facilitate localization of functional activation and pathology to individual nuclear subgroups.