Tuesday seminar deformable image registration
Download
1 / 28

Tuesday Seminar Deformable Image Registration - PowerPoint PPT Presentation


  • 237 Views
  • Uploaded on

07 th of January, 2014. Tuesday Seminar Deformable Image Registration. HyunSeok Lee leehseok @snu.ac.kr. Contents. What is Image Registration? Deformable Image Registration Basic concept Algorithm Products Open source Debates about dose deform TG132. What is image registration?.

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

PowerPoint Slideshow about ' Tuesday Seminar Deformable Image Registration' - ryann


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
Tuesday seminar deformable image registration

07th of January, 2014

Tuesday SeminarDeformable Image Registration

HyunSeok Lee

[email protected]


Contents
Contents

  • What is Image Registration?

  • Deformable Image Registration

    • Basic concept

    • Algorithm

    • Products

    • Open source

  • Debates about dose deform

  • TG132


What is image registration
What is image registration?

  • Image registration is the process of transforming different sets of data into one coordinate system.

  • Registration is necessary in order to be able to compare or integrate the data obtained from different measurements.


Ir rigid transformation
IR – Rigid Transformation

  • Rotation

  • Translation

  • Scale


Ir affine transformation
IR – Affine Transformation

  • Rotation

  • Translation

  • Scale

  • Shear

    • No more preservation of lengths and angles

    • Parallel lines are preserved


Ir perspective transformation
IR – Perspective Transformation

  • (xo, yo, zo)  world coordinates

  • (xi, yi)  image coordinates


Ir projective transformation
IR – Projective Transformation

  • (xp, yp)  Plane Coordinates

  • (xi, yi)  Image Coordinates

  • amn coefficients from the equations of the scene and the image planes


Ir non rigid transformation
IR – Non-Rigid Transformation

  • Needed for inter-subject registration and distortion correction

  • Non-linear

  • Many different parameterizations

  • Too much flexibility in the transformation can lead to undesirable results


Deformable image registration
Deformable Image Registration

  • Fundamental task in medical image processing

  • Typical uses

    • Longitudinal studies

      • where temporal structural or anatomical changes are investigated

    • Matching of images from different patients

    • Multi-modal registration

      • matching images of the same patient acquired by different imaging technologies



Dir products
DIR – Products

  • MIM Software Inc.

    • Intensity-based free-form deformable registration (VoxAlign)

    • PET/CT, MR/CT and 4D data sets deformable fusion

    • Atlas-based auto-contouring

    • Dose Accumulation

    • Adaptive re-contouring

    • Deformable registration QA and reporting


Intensity based methods
Intensity-based Methods

  • Intensity-based methods compare intensity patterns in images via correlation metrics

  • Sum of Squared Differences

  • Normalized Cross-Correlation

  • Mutual Information


Feature based methods
Feature-based Methods

  • Feature-based methods find correspondence between image features such as points, lines, and contours.

  • Distance between corresponding points

  • Similarity metric between feature values

    • e.g. curvature-based registration


Free form deformations
Free-form Deformations

  • The general idea is to deform an image by manipulating a regular grid of control points that are distributed across the image at an arbitrary mesh resolution.

  • Control points can be moved and the position of individual pixels between the control points is computed from the positions of surrounding control points.


Dir products1
DIR – Products

  • Mirada Medical

    • Algorithms are based on published algorithms but have been developed and optimized for particular RO use-cases and modality combinations.

      • e.g. CT-CT Optic Flow algorithm for PET/CT fusion

      • e.g. CT-MR multi-modal algorithm for MRI fusion

    • Multimodal deformable fusion

      • CT, PET, PET/CT, MRI and CBCT, including 4D data sets

    • Automatic contouring

      • using an atlas or previously contoured case

    • Dose warping and summation

    • Adaptive therapy


Dir products2
DIR – Products

  • Velocity Medical Solutions

    • Multi-resolution modified basis spline algorithm

    • Multi-modality demons algorithm

    • Multi-modality deformable image registration

      • CT, MR, PET and SPECT

    • Atlas-based auto-contouring

    • Treatment response assessment


Dir open source
DIR – Open Source

  • ITK

    • Insight Segmentation and Registration Toolkit

    • An extensive suite of software tools for image analysis

    • Implemented in C++

    • http://www.itk.org/itkindex.html


Dir open source1
DIR – Open Source

  • DIRART

    • Deformable Image Registration and Adaptive Radiotherapy

    • It contains well implemented DIR algorithms and the essential functions for ART applications.

    • Implemented in MATLAB

    • Need CERR

    • https://code.google.com/p/dirart/


Dir open source2
DIR – Open Source

  • Plastimatch

    • For high performance volumetric registration of medical images

    • ITK-based algorithms for translation, rigid, affine, demons, and B-spline registration

      • Some methods are GPU and multicore accelerated

    • Implemented in C++

    • Plugin to 3D Slicer

      • software package for visualization and medical image computing

    • http://plastimatch.org/



It is not appropriate to deform dose along with dir in art
It is not appropriate to “deform” dose along with DIR in ART

  • For ART it is common to collect images of the patient throughout the course of therapy.

  • Because of temporal variations, it is usually necessary to deform images so as to merge them into a cohesive dataset.

  • This image registration makes the accurate merging of dose distributions difficult.

  • Some have decided to do this by “deforming” the dose distributions, somewhat analogous to deforming the images, but it has been suggested that this is not appropriate.


Task group no 132
Task Group No. 132 ART

  • Use of Image Registration and Fusion Algorithms and Techniques in Radiotherapy

    • Emphasis the importance of acceptance testing, including end-to-end tests, phantom tests, and clinical data tests.

    • Describe the methods for validation and quality assurance of image registration techniques.

    • Describe techniques for patient specific validation.


Deformable presage dosimeter
Deformable PRESAGE ART® dosimeter




Dir algorithm1
DIR – Algorithm ART

  • Deformation Model


Dir algorithm2
DIR – Algorithm ART

  • Matching Criteria (Objective Function)


Dir algorithm3
DIR – Algorithm ART

  • Optimization Method


ad