Real-Time X-Ray CT

4/26/01


Click here to start


Table of Contents

Real-Time X-Ray CT

Outline

Ray-Sums

Computed Tomography

Outline

Real-Time Imaging Using X-Ray CT

4D Volume

Outline

Fourier Slice Theorem

From Projections to Image

Need for Filtering

Filtered Backprojection

Example: Projection

Example: Backprojection

Example: Backprojection

Example: Filtering

Example: Filtered Backprojection

Outline

Why the Iterative Approach?

Linear Imaging System

Linear System Example

Iterative Reconstruction Idea

Make a Guess x(0) !

Rectifying the 1st Equation

Rectifying the 2nd Equation

Rectifying the 3rd Equation

Rectifying the 4th Equation

Different Rectifying Factors

How to Compromise?

Check Relative Weights

Use Relative Weights

Overall Rectifying Factor

Expectation Maximization Formula

Outline

Ordered-Subset EM Formula

Convergence Behavior

Speed Improvement

Simulation - OSEM for Denoising

Further Work

Acknowledgments

Thank-You

Author: Ge Wang

Email: ge-wang@uiowa.edu

Home Page: http://dolphin.radiology.uiowa.edu/ge