skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Towards a practical implementation of the MLE algorithm for Positron Emission Tomography

Abstract

Recognizing that the quality of images obtained by application of the Maximum Likelihood Estimator (MLE) to Positron Emission Tomography (PET) and Single Photon Emission Tomography (SPECT) appears to be substantially better than those obtained by conventional methods, we have started to develop methods that will facilitate the necessary research for a good evaluation of the algorithm and may lead to its practical application for research and routine tomography. We have found that the non-linear MLE algorithm can be used with pixel sizes which are smaller than the sampling distance, without interpolation, obtaining excellent resolution and no noticeable increase in noise. We have studied the role of symmetry in reducing the amount of matrix element storage requirements for full size applications of the algorithm and have used that concept to carry out two reconstructions of the Derenzo phantom with data from the ECAT-III instrument. The results show excellent signal-to-noise (S/N) ratio, particularly for data with low total counts, excellent sharpness, but low contrast at high frequencies when using the Shepp-Vardi model for probability matrices. 12 refs., 7 figs., 4 tabs.

Authors:
; ; ;
Publication Date:
Research Org.:
Lawrence Berkeley Lab., CA (USA); California Univ., Los Angeles (USA). Dept. of Radiological Sciences
OSTI Identifier:
6083620
Report Number(s):
LBL-19668; CONF-851009-45
ON: DE86005223
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Conference
Resource Relation:
Conference: IEEE nuclear science symposium, San Francisco, CA, USA, 23 Oct 1985; Other Information: Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; ALGORITHMS; PERFORMANCE TESTING; POSITRON COMPUTED TOMOGRAPHY; IMAGE PROCESSING; SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY; EXPERIMENTAL DATA; MAXIMUM-LIKELIHOOD FIT; NONLINEAR PROGRAMMING; COMPUTERIZED TOMOGRAPHY; DATA; DIAGNOSTIC TECHNIQUES; EMISSION COMPUTED TOMOGRAPHY; INFORMATION; MATHEMATICAL LOGIC; NUMERICAL DATA; NUMERICAL SOLUTION; PROCESSING; PROGRAMMING; TESTING; TOMOGRAPHY; 550602* - Medicine- External Radiation in Diagnostics- (1980-)

Citation Formats

Llacer, J, Andreae, S, Veklerov, E, and Hoffman, E J. Towards a practical implementation of the MLE algorithm for Positron Emission Tomography. United States: N. p., 1985. Web.
Llacer, J, Andreae, S, Veklerov, E, & Hoffman, E J. Towards a practical implementation of the MLE algorithm for Positron Emission Tomography. United States.
Llacer, J, Andreae, S, Veklerov, E, and Hoffman, E J. Tue . "Towards a practical implementation of the MLE algorithm for Positron Emission Tomography". United States.
@article{osti_6083620,
title = {Towards a practical implementation of the MLE algorithm for Positron Emission Tomography},
author = {Llacer, J and Andreae, S and Veklerov, E and Hoffman, E J},
abstractNote = {Recognizing that the quality of images obtained by application of the Maximum Likelihood Estimator (MLE) to Positron Emission Tomography (PET) and Single Photon Emission Tomography (SPECT) appears to be substantially better than those obtained by conventional methods, we have started to develop methods that will facilitate the necessary research for a good evaluation of the algorithm and may lead to its practical application for research and routine tomography. We have found that the non-linear MLE algorithm can be used with pixel sizes which are smaller than the sampling distance, without interpolation, obtaining excellent resolution and no noticeable increase in noise. We have studied the role of symmetry in reducing the amount of matrix element storage requirements for full size applications of the algorithm and have used that concept to carry out two reconstructions of the Derenzo phantom with data from the ECAT-III instrument. The results show excellent signal-to-noise (S/N) ratio, particularly for data with low total counts, excellent sharpness, but low contrast at high frequencies when using the Shepp-Vardi model for probability matrices. 12 refs., 7 figs., 4 tabs.},
doi = {},
url = {https://www.osti.gov/biblio/6083620}, journal = {},
number = ,
volume = ,
place = {United States},
year = {1985},
month = {10}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: