Accounting for anatomical noise in SPECT with a visual-search human-model observer

Autor: Gifford, H. C., King, M. A., Smyczynski, M. S.
Zdroj: Proceedings of SPIE; March 2011, Vol. 7966 Issue: 1 p79660H-79660H-8, 716949p
Abstrakt: Reliable human-model observers for clinically realistic detection studies are of considerable interest in medical imaging research, but current model observers require frequent revalidation with human data. A visual-search (VS) observer framework may improve reliability by better simulating realistic etection-localization tasks. Under this framework, model observers execute a holistic search to identify tumor-like candidates and then perform careful analysis of these candidates. With emission tomography, anatomical noise in the form of elevated uptake in neighboring tissue often complicates the task. Some scanning model observers simulate the human ability to read around such noise by presubtracting the mean normal background from the test image, but this backgroundknown- exactly (BKE) assumption has several drawbacks. The extent to which the VS observer can overcome these drawbacks was investigated by comparing it against humans and a scanning observer for detection of solitary pulmonary nodules in a simulated SPECT lung study. Our results indicate that the VS observer offers a robust alternative to the scanning observer for modeling humans.
Databáze: Supplemental Index