Visual-search observers for assessing tomographic x-ray image quality.
Visual-search observers for assessing tomographic x-ray image quality.
复制标题
用于评估断层 X 射线图像质量的视觉搜索观察者。
DOI：
10.1118/1.4942485
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发表时间：
2016
期刊：
影响因子：
3.8
通讯作者：
Das,Mini
中科院分区：
文献类型：
--
作者：
Gifford,HowardC;Liang,Zhihua;Das,Mini
在x射线成像研究中，通常用于诊断图像质量评估的数学模型观察者由于需要统计先验信息，通常被限制在相对简单的检测任务中。在顺序搜索和分析阶段使用形态学特征的视觉搜索（VS）模型观察者对这些信息的需求更少，任务约束也更少。在一项初步研究中，作者将4个VS观测者与人类观测者和一个现有的扫描模型观测者进行了比较，该研究量化了在模拟数字乳房断层合成（DBT）中的质量检测和定位如何受到获得的投影数量的影响。方法采用内嵌球形肿块的数字乳房影像作为定位接收机工作特性（LROC）研究的单一靶点。在p值为3 ~ 51之间，生成了基于60°采集弧的DBT投影集。利用滤波后的反投影和恒定的三维巴特沃斯后滤波重建DBT体；提取的二维切片作为测试图像。三位成像物理学家作为观察员参与。扫描通道化非预白化（CNPW）观察者知道平均病变缺失图像。VS观察者计算了一个初始的单特征搜索统计量，该统计量将候选位置识别为模板匹配滤波（MF）图像或梯度模板MF （GMF）图像的局部最大值。还考虑了修改统计数据的搜索效率低下。随后的VS候选分析使用(i) CNPW统计判别法和（ii） GMF训练图像计算的判别法进行。这些位置不变判别式不利用协方差信息。所有观察者平均阅读36张训练图像和108张研究图像。根据LROC曲线下的面积对表现进行评分。结果人类观察者的平均表现在7 - 35岁之间是稳定的。在没有搜索效率低下的情况下，基于GMF分析的VS模型与人类结果提供了最佳相关性（Pearsonρ≥0.62）。基于CNPW的VS观测者主要在p值较低时偏离人类。在这个有限的研究中，搜索效率低下允许大多数VS观察者与人类达成良好的定量协议。结论VS观测器的计算效率训练要求适用于高分辨率成像，表明观测器框架有潜力克服当前模型观测器在x射线应用中的重要任务限制。
PurposeMathematical model observers commonly used for diagnostic image‐quality assessments in x‐ray imaging research are generally constrained to relatively simple detection tasks due to their need for statistical prior information. Visual‐search (VS) model observers that employ morphological features in sequential search and analysis stages have less need for such information and fewer task constraints. The authors compared four VS observers against human observers and an existing scanning model observer in a pilot study that quantified how mass detection and localization in simulated digital breast tomosynthesis (DBT) can be affected by the numberPof acquired projections.MethodsDigital breast phantoms with embedded spherical masses provided single‐target cases for a localization receiver operating characteristic (LROC) study. DBT projection sets based on an acquisition arc of 60° were generated for values ofPbetween 3 and 51. DBT volumes were reconstructed using filtered backprojection with a constant 3D Butterworth postfilter; extracted 2D slices were used as test images. Three imaging physicists participated as observers. A scanning channelized nonprewhitening (CNPW) observer had knowledge of the mean lesion‐absent images. The VS observers computed an initial single‐feature search statistic that identified candidate locations as local maxima of either a template matched‐filter (MF) image or a gradient‐template MF (GMF) image. Search inefficiencies that modified the statistic were also considered. Subsequent VS candidate analyses were carried out with (i) the CNPW statistical discriminant and (ii) the discriminant computed from GMF training images. These location‐invariant discriminants did not utilize covariance information. All observers read 36 training images and 108 study images perPvalue. Performance was scored in terms of area under the LROC curve.ResultsAverage human‐observer performance was stable forPbetween 7 and 35. In the absence of search inefficiencies, the VS models based on the GMF analysis provided the best correlation (Pearsonρ≥ 0.62) with the human results. The CNPW‐based VS observers deviated from the humans primarily at lower values ofP. In this limited study, search inefficiencies allowed for good quantitative agreement with the humans for most of the VS observers.ConclusionsThe computationally efficient training requirements for the VS observer are suitable for high‐resolution imaging, indicating that the observer framework has the potential to overcome important task limitations of current model observers for x‐ray applications.
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影响因子：
1.8
作者：
Eckstein, Miguel P.
通讯作者：
Eckstein, Miguel P.
信号已知统计任务（SKS）的模型观察者
DOI：
--
发表时间：
2001
期刊：
SPIE Medical Imaging
影响因子：
--
作者：
M. Eckstein;C. Abbey
通讯作者：
C. Abbey
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DOI：
--
发表时间：
2008
期刊：
SPIE Medical Imaging
影响因子：
--
作者：
H. Gifford;C. Didier;C. Didier;M. Das;S. Glick
通讯作者：
S. Glick
影响因子：
3.8
作者：
SIDDON, RL
通讯作者：
SIDDON, RL
影响因子：
4.8
作者：
G. Gazelle;S. Seltzer;P. Judy
通讯作者：
P. Judy