Effect of block-iterative acceleration on Ga-67 tumor detection in thoracic SPECT
| Autor: | Michael A. King, P.H. Pretorius, Howard C. Gifford, Manoj Narayanan, R.G. Wells, M.S. Smyczynski |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Nuclear and High Energy Physics
Observer (quantum physics) Receiver operating characteristic medicine.diagnostic_test Iterative method Iterative reconstruction Single-photon emission computed tomography Imaging phantom Noise Nuclear Energy and Engineering Expectation–maximization algorithm medicine Electrical and Electronic Engineering Algorithm |
| Zdroj: | IEEE Transactions on Nuclear Science. 49:50-55 |
| ISSN: | 1558-1578 0018-9499 |
| DOI: | 10.1109/tns.2002.998680 |
| Popis: | A combination of human localization receiver operating characteristic (LROC) and channelized Hotelling observer (CHO) ROC psychophysical studies were used to investigate how accelerated ordered-subset expectation maximization (OSEM) and rescaled block-iterative (RBI) EM reconstruction affect tumor detection in simulated Ga-67 SPECT images, The tumors were 1-cm-diameter spheres within the chest region of the three-dimensional mathematical cardiac-torso phantom. Previous work with iterative detector resolution compensation showed that eight iterations of the OSEM algorithm with a subset size of eight (16 subsets) offered optimal observer performance. For the LROC study in this paper, the OSEM and RBI algorithms were implemented using subset sizes P and iterations K that satisfied the relation P=K for P=1, 2, 4, and 8. The CHO was applied to reconstruction strategies that deviated from this relation. Results show that using P/spl les/2 penalized observer performance compared to strategies with larger subset sizes. Other researchers have reported on the more stable convergence and noise properties of the RBI algorithm [(Byrne, 1996) and (Lalush and Tsui, 2000)]. In a similar vein, we found that an RBI strategy with a subset size of P produced the same performance as an OSEM strategy with subset size 2P. As neither algorithm displayed a decisive advantage in speed over the other, we conclude that the RBI algorithm is the better choice for accelerating the Ga-67 reconstructions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|