Group wise registration in namic kit
1 / 19

Group-wise Registration in NAMIC-kit - PowerPoint PPT Presentation

  • Uploaded on

Group-wise Registration in NAMIC-kit. Serdar K Balci (MIT) Lilla Zöllei (MGH) Kinh Tieu (BWH) Mert R Sabuncu (MIT) Polina Golland (MIT). Robust Group-wise Registration. Entropy based group-wise registration ITK implementation Empirical Evaluation.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Group-wise Registration in NAMIC-kit' - giulio

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Group wise registration in namic kit

Group-wise Registration in NAMIC-kit

Serdar K Balci (MIT)

LillaZöllei (MGH)

KinhTieu (BWH)

Mert R Sabuncu (MIT)

PolinaGolland (MIT)

Robust group wise registration
Robust Group-wise Registration

  • Entropy based group-wise registration

  • ITK implementation

  • Empirical Evaluation

Background groupwise registration
Background: Groupwise Registration

  • Images Transforms

  • Transforms:

    • Affine

    • Non-rigid using B-Splines

Groupwise registration congealing
Groupwise Registration: Congealing

L . Zöllei, E. Learned-Miller, E. Grimson, W.M. Wells III.

"Efficient Population Registration of 3D Data."

Congealing intuition
Congealing: Intuition

  • If Gaussian

  • If also

    • Registering to the mean with LS metric


  • ITK classes

    • Group-wise registration using congealing

      • Variance

      • Entropy


Before Affine BS 4 BS 8 BS 16



Full term babies
Full Term Babies

Before Affine BS 4

BS 8 BS 16 BS 32

Pre term babies
Pre Term Babies

Before Affine BS 4

BS 8 BS 16


  • Implemented group-wise registration in ITK

    • Congealing: Entropy based registration

    • Affine and BSpline

    • Multithreaded implementation

    • *Bspline optimization

  • Initial Evaluation

    • A population of 50 subjects

    • Used segmentation labels to evaluate

Ongoing work
Ongoing Work

  • Finding optimal parameters

    • B-Spline mesh size,

    • # of hierarchical levels

    • Subsampling

  • Quantitative comparison to other methods

    • Pair-wise registration to the mean using MI

Congealing with two images
Congealing with Two Images

  • Using Parzen windows

  • As we only have two images

  • Pairwise registration using LS metric

Groupwise reg using pairwise reg
Groupwise Reg. using Pairwise Reg.

  • If we assume that images are independent given a subject, representative of the population

Registering to the mean
Registering to the mean

  • We assume independence over images

  • and draw i.i.d. samples from each image

Groupwise registration using joint entropy
Groupwise Registration using Joint Entropy

  • Assume i.i.d over space, but don’t make any assumptions about images

  • Estimating entropy of an N-dimensional distribution is a challenging task

Results congealing with entropy
Results: Congealing with Entropy

Before After (B-Splines ~20mm)