The ML-EM Algorithm is Not Optimal for Poisson Noise

The ML-EM (maximum likelihood expectation maximization) algorithm is the most popular image reconstruction method when the measurement noise is Poisson distributed. This short paper considers the problem that for a given noisy projection data set, whether the ML-EM algorithm is able to provide an approximate solution that is close to the true solution. It is well-known that the ML-EM algorithm at early iterations converges towards the true solution and then in later iterations diverges away from the true solution. Therefore a potential good approximate solution can only be obtained by early termination. This short paper argues that the ML-EM algorithm is not optimal in providing such an approximate solution. In order to show that the ML-EM algorithm is not optimal, it is only necessary to provide a different algorithm that performs better. An alternative algorithm is suggested in this paper and this alternative algorithm is able to outperform the ML-EM algorithm.

Medienart:

E-Artikel

Erscheinungsjahr:

2015

Erschienen:

2015

Enthalten in:

Zur Gesamtaufnahme - volume:2015

Enthalten in:

IEEE transactions on nuclear science - 2015(2015) vom: 21. Okt.

Sprache:

Englisch

Beteiligte Personen:

Zeng, Gengsheng L [VerfasserIn]

Links:

Volltext

Themen:

Computed tomography
Expectation maximization (EM)
Iterative reconstruction
Journal Article
Maximum likelihood (ML)
Noise weighted image reconstruction
Poisson noise
Positron emission tomography (PET)
Single photon emission computed tomography (SPECT)

Anmerkungen:

Date Revised 27.03.2024

published: Print

Citation Status PubMed-not-MEDLINE

doi:

10.1109/NSSMIC.2015.7582178

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM276063597