Matches in SemOpenAlex for { <https://semopenalex.org/work/W97818856> ?p ?o ?g. }
Showing items 1 to 81 of
81
with 100 items per page.
- W97818856 abstract "A new method for calculation of ROI values has been developed from the EM maximum likelihood reconstruction algorithm. The current problem is that ROI values extracted from filtered backprojection (FBP) images are biased due to the partial volume effect and the reconstruction filter. The new algorithm incorporates a physical-statistical model of the projection data and requires knowledge of the location of all ROIs to define its ''pixels''. Unbiased estimates of ROI concentrations are directly estimated, i.e. the bias due to the partial volume effect has been removed. In addition, a dramatic reduction in computation time compared to the EM reconstruction is achieved due to the reduced number of pixels and the improved convergence characteristics. The new algorithm was tested with simulated tomographic projection data generated at a range of count rates with 1 cm resolution. ROI values were estimated directly by the extended EM algorithm. FBP reconstructions were performed with high and low resolution filters and ROI values were extracted with a range of concentric regions within the true ROI. With no noise, the FBP values were biased from 3 to 40% (less bias for small concentric regions in large ROIs) while the EM values (50 iterations) were less thanmore » 0.5% biased. For the noisy simulations, the EM estimates had 2 to 4 times smaller standard deviation than small concentric FBP regions and comparable noise to large FBP regions which are significantly biased. This demonstrates that use of a physical statistical, and anatomical information with the approplate algorithm can significantly improve the accuracy of tomographic ROI measurements.« less" @default.
- W97818856 created "2016-06-24" @default.
- W97818856 creator A5012357230 @default.
- W97818856 creator A5038607266 @default.
- W97818856 creator A5066001933 @default.
- W97818856 date "1985-05-01" @default.
- W97818856 modified "2023-09-23" @default.
- W97818856 title "A maximum likelihood method for calculation of tomographic region-of-interest (ROI) values" @default.
- W97818856 hasPublicationYear "1985" @default.
- W97818856 type Work @default.
- W97818856 sameAs 97818856 @default.
- W97818856 citedByCount "2" @default.
- W97818856 crossrefType "journal-article" @default.
- W97818856 hasAuthorship W97818856A5012357230 @default.
- W97818856 hasAuthorship W97818856A5038607266 @default.
- W97818856 hasAuthorship W97818856A5066001933 @default.
- W97818856 hasConcept C105795698 @default.
- W97818856 hasConcept C106131492 @default.
- W97818856 hasConcept C11413529 @default.
- W97818856 hasConcept C115961682 @default.
- W97818856 hasConcept C141379421 @default.
- W97818856 hasConcept C154945302 @default.
- W97818856 hasConcept C159985019 @default.
- W97818856 hasConcept C160633673 @default.
- W97818856 hasConcept C192562407 @default.
- W97818856 hasConcept C19609008 @default.
- W97818856 hasConcept C204323151 @default.
- W97818856 hasConcept C205372480 @default.
- W97818856 hasConcept C22679943 @default.
- W97818856 hasConcept C31972630 @default.
- W97818856 hasConcept C33923547 @default.
- W97818856 hasConcept C41008148 @default.
- W97818856 hasConcept C57493831 @default.
- W97818856 hasConcept C82233179 @default.
- W97818856 hasConcept C99498987 @default.
- W97818856 hasConceptScore W97818856C105795698 @default.
- W97818856 hasConceptScore W97818856C106131492 @default.
- W97818856 hasConceptScore W97818856C11413529 @default.
- W97818856 hasConceptScore W97818856C115961682 @default.
- W97818856 hasConceptScore W97818856C141379421 @default.
- W97818856 hasConceptScore W97818856C154945302 @default.
- W97818856 hasConceptScore W97818856C159985019 @default.
- W97818856 hasConceptScore W97818856C160633673 @default.
- W97818856 hasConceptScore W97818856C192562407 @default.
- W97818856 hasConceptScore W97818856C19609008 @default.
- W97818856 hasConceptScore W97818856C204323151 @default.
- W97818856 hasConceptScore W97818856C205372480 @default.
- W97818856 hasConceptScore W97818856C22679943 @default.
- W97818856 hasConceptScore W97818856C31972630 @default.
- W97818856 hasConceptScore W97818856C33923547 @default.
- W97818856 hasConceptScore W97818856C41008148 @default.
- W97818856 hasConceptScore W97818856C57493831 @default.
- W97818856 hasConceptScore W97818856C82233179 @default.
- W97818856 hasConceptScore W97818856C99498987 @default.
- W97818856 hasLocation W978188561 @default.
- W97818856 hasOpenAccess W97818856 @default.
- W97818856 hasPrimaryLocation W978188561 @default.
- W97818856 hasRelatedWork W1728377051 @default.
- W97818856 hasRelatedWork W1909367084 @default.
- W97818856 hasRelatedWork W1975590811 @default.
- W97818856 hasRelatedWork W1976419543 @default.
- W97818856 hasRelatedWork W2044256813 @default.
- W97818856 hasRelatedWork W2048042021 @default.
- W97818856 hasRelatedWork W2068488490 @default.
- W97818856 hasRelatedWork W2086784799 @default.
- W97818856 hasRelatedWork W2093366077 @default.
- W97818856 hasRelatedWork W2110424675 @default.
- W97818856 hasRelatedWork W2121844714 @default.
- W97818856 hasRelatedWork W2133942600 @default.
- W97818856 hasRelatedWork W2188830082 @default.
- W97818856 hasRelatedWork W2532824498 @default.
- W97818856 hasRelatedWork W2543971069 @default.
- W97818856 hasRelatedWork W2545987984 @default.
- W97818856 hasRelatedWork W2577245722 @default.
- W97818856 hasRelatedWork W262863015 @default.
- W97818856 hasRelatedWork W3009062928 @default.
- W97818856 hasRelatedWork W2184216489 @default.
- W97818856 isParatext "false" @default.
- W97818856 isRetracted "false" @default.
- W97818856 magId "97818856" @default.
- W97818856 workType "article" @default.