Performance of MAP Reconstruction for Hot Lesion Detection in Whole-Body PET/CT: An Evaluation With Human and Numerical Observers
Performance of MAP Reconstruction for Hot Lesion Detection in Whole-Body PET/CT: An Evaluation With Human and Numerical Observers
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DOI：
10.1109/tmi.2008.927349
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发表时间：
2009-01-01
影响因子：
10.6
通讯作者：
Verscuren, Raf
中科院分区：
文献类型：
--
作者：
Nuyts, Johan;Michel, Christian;Verscuren, Raf
正电子发射断层扫描(PET)成像可以采用不同的重建方法，包括最大似然(ML)重建和最大后验概率(MAP)重建。平滑后的ML图像具有与位置和物体近似无关的空间分辨率，这有利于(半)定量分析。然而，使用MAP获得的复杂对象相关平滑可能会改善噪声特性，有利于病变检测。在这一贡献中，比较了MAP和后平滑ML在人类观察者检测热点方面的作用，并使用信道化霍特林观测器(CHO)。研究设计基于“多项选择强迫选择”的方法。对于地图重建，使用了相对差值先验。对于后平滑的最大似然方法，使用了高斯平滑核。人类观察者和CHO在地图图像上的表现都略好于在后平滑ML图像上的表现。CHO的平均表现与人类最好的表现相似。然后，将CHO应用于评估先验的性能，并减少了对差异较大的惩罚。对于这些先验，检测性能较差。
For positron emission tomography (PET) imaging, different reconstruction methods can be applied, including maximum likelihood (ML) and maximum a posteriori (MAP) reconstruction. Postsmoothed ML images have approximately position and object independent spatial resolution, which is advantageous for (semi-) quantitative analysis. However, the complex object dependent smoothing obtained with MAP might yield improved noise characteristics, beneficial for lesion detection. In this contribution, MAP and postsmoothed ML are compared for hot spot detection by human observers and fly the channelized Hotelling observer (CHO). The study design was based on the "multiple alternative forced choice" approach. For the MAP reconstruction, the relative difference prior was used. For postsmoothed ML, a Gaussian smoothing kernel was used. Both the human observers and the CHO performed slightly better on MAP images than on postsmoothed ML images. The average CHO performance was similar to the best human performance. The CHO was then applied to evaluate the performance of priors with reduced penalty for large differences. For these priors, a poorer detection performance was obtained.