PDE methods for DWMRI Analysis and Image Registration presented by John Melonakos – NAMIC Core 1 Workshop – 31/May/2007
Jan 22, 2016
PDE methods for DWMRI Analysis and Image Registrationpresented by John Melonakos – NAMIC Core 1 Workshop – 31/May/2007
2
Outline
Geodesic Tractography Review
Cingulum Bundle Tractography--------------------------------------------- Fast Numerical Schemes
Applications to Image Registration
3
Contributors
Georgia Tech- John Melonakos, Vandana
Mohan, Allen Tannenbaum BWH-
Marc Niethammer, Kate Smith, Marek Kubicki, Martha Shenton
UCI- Jim Fallon
4
Publications
J. Melonakos, E. Pichon, S. Angenent, A. Tannenbaum. “Finsler Active Contours”. IEEE Transactions on Pattern Analysis and Machine Intelligence. (to appear 2007).
J. Melonakos, V. Mohan, M. Niethammer, K. Smith, M. Kubicki, A. Tannenbaum. “Finsler Tractography for White Matter Connectivity Analysis of the Cingulum Bundle”. MICCAI 2007.
V. Mohan, J. Melonakos, M. Niethammer, M. Kubicki, A. Tannenbaum. “Finsler Level Set Segmentation for Imagery in Oriented Domains”. BMVC 2007 (in submission).
Eric Pichon and Allen Tannenbaum. Curve segmentation using directional information, relation to pattern detection. In IEEE International Conference on Image Processing (ICIP), volume 2, pages 794-797, 2005.
Eric Pichon, Carl-Fredrik Westin, and Allen Tannenbaum. A Hamilton-Jacobi-Bellman approach to high angular resolution diffusion tractography. In International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI), pages 180-187, 2005.
5
Directional Dependence
tangentdirection
the new length functional
This is a metric on a “Finsler” manifold if Ψ satisfies certain properties.
6
Finsler Metrics
the Finsler properties:
• Regularity
• Positive homogeneity of degree one in the second variable
• Strong Convexity
Note: Finsler geometry is a generalization of Riemannian geometry.
7
Computing the first variation of the functional E, the L2-optimal E-minimizing deformation is:
Closed Curves:The Flow Derivation
8
Consider a seed region S½Rn, define for all target points t2Rn the value function:
curves between S and t
It satisfies the Hamilton-Jacobi-Bellman equation:
Open Curves:The Value Function
9
Numerics
Closed Curves Open Curves
Level Set Techniques Dynamic Programming(Fast Sweeping)
10
Finsler vs Riemann vs Euclid
11
Outline
Geodesic Tractography Review
Cingulum Bundle Tractography--------------------------------------------- Fast Numerical Schemes
Applications to Image Registration
12
A Novel Approach
Use open curves to find the optimal “anchor tract” connecting two ROIs
Initialize a level set surface evolution on the anchor tract to capture the entire fiber bundle.
13
The Cingulum Bundle
5-7 mm in diameter
“ring-like belt” around CC
Involved in executive control and emotional processing
14
The Data
24 datasets from BWH (Marek Kubicki)12 Schizophrenics12 Normal Controls
54 Sampling Directions
15
The Algorithm Input
Locating the bundle endpoints (work done by Kate Smith)
16
The Algorithm Input
How the ROIs were drawn
17
Results
Anterior View
Posterior View
18
Results
19
Results
20
Results – A Statistical Note
Attempt to sub-divide the tract to find FA significance
21
Work In Progress
Implemented a level set surface evolution to capture the entire bundle – preliminary results.
Working with Marek Kubicki and Jim Fallon to make informed subdivision of the bundle for statistical processing.
Linking the technique to segmentation work in order to connect brain structures.
22
Outline
Geodesic Tractography Review
Cingulum Bundle Tractography--------------------------------------------- Fast Numerical Schemes
Applications to Image Registration
23
Contributors
Georgia Tech- Gallagher Pryor, Tauseef
Rehman, John Melonakos, Allen Tannenbaum
24
Publications
T. Rehman, G. Pryor, J. Melonakos, I. Talos, A. Tannenbaum. “Multi-resolution 3D Nonrigid Registration via Optimal Mass Transport”. MICCAI 2007 workshop (in submission).
T. Rehman, G. Pryor, and A. Tannenbaum. Fast Optimal Mass Transport for Dynamic Active Contour Tracking on the GPU. In IEEE Conference on Decision and Control, 2007 (in submission).
G. Pryor, T. Rehman, A. Tannenbaum. BMVC 2007 (in submission).
25
Multigrid Numerical Schemes
26
Parallel Computing
27
Algorithms on the GPU
28
Parallel Computing
29
Parallel Computing
30
Outline
Geodesic Tractography Review
Cingulum Bundle Tractography--------------------------------------------- Fast Numerical Schemes
Applications to Image Registration
31
The Registration Problem
Synthetic Registration Problem
32
Solution – The Warped Grid
Synthetic Registration Problem
33
The Registration Problem
Brain Sag Registration Problem
Before After
34
Solution – The Warped Grid
35
Speedup
A 128^3 registration in less than 15 seconds
36
Key Conclusions
Multigrid algorithms on the GPU can dramatically increase performance
We used Optimal Mass Transport for registration, but other PDEs may also be implemented in this way
37
Questions?