2016_Imaging for Physicists

Iterative reconstruction: ML-EM

 Iterative reconstruction ●

Discrete representation of data and image  Expectation maximization (EM) algorithm offers deter- mination of maximum likelihood (ML) estimate of the image

Image space

Projection space

Estimated Projection

Forward projection

Current image estimate

Measured Projection

Comparison

Update Error Image

estimate

Back- projection

Error Projection

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ESTRO Teaching Course Advanced Imaging: PET – Reconstruction, Contouring