Evaluation of a method for projection-based tissue-activity estimation within small volumes of interest.
Evaluation of a method for projection-based tissue-activity estimation within small volumes of interest.
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DOI：
10.1088/0031-9155/57/3/685
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发表时间：
2012-02-07
影响因子：
3.5
通讯作者：
Moore SC
中科院分区：
文献类型：
--
作者：
Southekal S;McQuaid SJ;Kijewski MF;Moore SC
SPECT成像评价了一种新的补偿组织分数和计数溢出效应的方法，该方法仅需要在感兴趣的原发病变周围的小体积内进行组织分割。通过将测量的投影数据拟合到分割的组织投影的统计模型来获得组织活性浓度估计。模拟了两个模拟人体躯干幻影的多个实现，每个幻影包含20个直径为1.6 cm的球形“肿瘤”，肿瘤与背景的比例为8：1和4：1。在准确度和精密度的基础上，将均匀和不均匀组织活性的肿瘤和背景活性浓度值的估计值与标准SUV指标进行比较。对于在无散射的均匀背景中完美配准的高对比度浅表病变，该方法产生了模拟活动值的准确（<0.4%偏倚）和精确（<6.1%）恢复，显著优于SUV指标。组织的不均匀性，更大的肿瘤深度和更低的对比度降低精度（高达11.7%），但估计仍然几乎是无偏的。该方法是可比的准确性，但更精确的比一个完善的矩阵求逆方法，即使在肿瘤的大小和位置的错误被引入到模拟中等不准确的分割和图像配准。物体中的光子散射不会显著影响估计的准确性或精度。
A new method of compensating for tissue-fraction and count-spillover effects, which requires tissue segmentation only within a small volume surrounding the primary lesion of interest, was evaluated for SPECT imaging. Tissue-activity concentration estimates are obtained by fitting the measured projection data to a statistical model of the segmented tissue projections. Multiple realizations of two simulated human-torso phantoms, each containing 20 spherical “tumours”, 1.6 cm in diameter, with tumour-to-background ratios of 8:1 and 4:1, were simulated. Estimates of tumour- and background-activity concentration values for homogeneous as well as inhomogeneous tissue activities were compared to standard SUV metrics on the basis of accuracy and precision. For perfectly registered, high-contrast, superficial lesions in a homogeneous background without scatter, the method yielded accurate (<0.4% bias) and precise (<6.1%) recovery of the simulated activity values, significantly outperforming the SUV metrics. Tissue inhomogeneities, greater tumour depth and lower contrast ratios degraded precision (up to 11.7%), but the estimates remained almost unbiased. The method was comparable in accuracy but more precise than a well-established matrix inversion approach, even when errors in tumor size and position were introduced to simulate moderate inaccuracies in segmentation and image registration. Photon scatter in the object did not significantly affect the accuracy or precision of the estimates.
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影响因子：
3.5
作者：
McQuaid SJ;Southekal S;Kijewski MF;Moore SC
通讯作者：
Moore SC
DOI：
10.1007/s00259-010-1704-x
发表时间：
2011-05-01
影响因子：
9.1
作者：
Gerbaudo, Victor H.;Mamede, Marcelo;Sugarbaker, David J.
通讯作者：
Sugarbaker, David J.
影响因子：
3.5
作者：
BARRETT, HH;WILSON, DW;TSUI, BMW
通讯作者：
TSUI, BMW
影响因子：
1.3
作者：
CARSON, RE
通讯作者：
CARSON, RE
DOI：
10.1097/00004647-199607000-00016
发表时间：
1996-07-01
影响因子：
6.3
作者：
Meltzer, CC;Zubieta, JK;Frost, JJ
通讯作者：
Frost, JJ