Abstract
The low signal-to-noise ratio (SNR) in emission data has stimulated the development of statistical image reconstruction methods based on the maximum a posteriori (MAP) principle. Experimental examples have shown that statistical methods improve image quality compared to the conventional filtered backprojection (FBP) method. However, these results depend on isolated data sets. Here we study the lesion detectability of MAP reconstruction theoretically, using computer observers. These theoretical results can be applied to different object structures. They show that for a quadratic smoothing prior, the lesion detectability using the prewhitening observer is independent of the smoothing parameter and the neighborhood of the prior, while the nonprewhitening observer exhibits an optimum smoothing point. We also compare the results to those of FBP reconstruction. The comparison shows that for ideal positron emission tomography (PET) systems (where data are true line integrals of the tracer distribution) the MAP reconstruction has a higher SNR for lesion detection than FBP reconstruction due to the modeling of the Poisson noise. For realistic systems, MAP reconstruction further benefits from accurately modeling the physical photon detection process in PET.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 815-822 |
| Number of pages | 8 |
| Journal | IEEE Transactions on Medical Imaging |
| Volume | 20 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 2001 |
| Externally published | Yes |
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Keywords
- Computer observer
- Lesion detection
- MAP estimation
- Positron emission tomography
ASJC Scopus subject areas
- Biomedical Engineering
- Radiology Nuclear Medicine and imaging
- Radiological and Ultrasound Technology
- Electrical and Electronic Engineering
- Computer Science Applications
- Computational Theory and Mathematics
Cite this
Theoretical study of lesion detectability of MAP reconstruction using computer observers. / Qi, Jinyi; Huesman, Ronald H.
In: IEEE Transactions on Medical Imaging, Vol. 20, No. 8, 08.2001, p. 815-822.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Theoretical study of lesion detectability of MAP reconstruction using computer observers
AU - Qi, Jinyi
AU - Huesman, Ronald H.
PY - 2001/8
Y1 - 2001/8
N2 - The low signal-to-noise ratio (SNR) in emission data has stimulated the development of statistical image reconstruction methods based on the maximum a posteriori (MAP) principle. Experimental examples have shown that statistical methods improve image quality compared to the conventional filtered backprojection (FBP) method. However, these results depend on isolated data sets. Here we study the lesion detectability of MAP reconstruction theoretically, using computer observers. These theoretical results can be applied to different object structures. They show that for a quadratic smoothing prior, the lesion detectability using the prewhitening observer is independent of the smoothing parameter and the neighborhood of the prior, while the nonprewhitening observer exhibits an optimum smoothing point. We also compare the results to those of FBP reconstruction. The comparison shows that for ideal positron emission tomography (PET) systems (where data are true line integrals of the tracer distribution) the MAP reconstruction has a higher SNR for lesion detection than FBP reconstruction due to the modeling of the Poisson noise. For realistic systems, MAP reconstruction further benefits from accurately modeling the physical photon detection process in PET.
AB - The low signal-to-noise ratio (SNR) in emission data has stimulated the development of statistical image reconstruction methods based on the maximum a posteriori (MAP) principle. Experimental examples have shown that statistical methods improve image quality compared to the conventional filtered backprojection (FBP) method. However, these results depend on isolated data sets. Here we study the lesion detectability of MAP reconstruction theoretically, using computer observers. These theoretical results can be applied to different object structures. They show that for a quadratic smoothing prior, the lesion detectability using the prewhitening observer is independent of the smoothing parameter and the neighborhood of the prior, while the nonprewhitening observer exhibits an optimum smoothing point. We also compare the results to those of FBP reconstruction. The comparison shows that for ideal positron emission tomography (PET) systems (where data are true line integrals of the tracer distribution) the MAP reconstruction has a higher SNR for lesion detection than FBP reconstruction due to the modeling of the Poisson noise. For realistic systems, MAP reconstruction further benefits from accurately modeling the physical photon detection process in PET.
KW - Computer observer
KW - Lesion detection
KW - MAP estimation
KW - Positron emission tomography
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UR - http://www.scopus.com/inward/citedby.url?scp=0035413318&partnerID=8YFLogxK
U2 - 10.1109/42.938249
DO - 10.1109/42.938249
M3 - Article
VL - 20
SP - 815
EP - 822
JO - IEEE Transactions on Medical Imaging
JF - IEEE Transactions on Medical Imaging
SN - 0278-0062
IS - 8
ER -