Thompson John D, Thomas Nigel B, Manning David J, Hogg Peter
Directorate of Radiology, University of Salford, Manchester, UK.
Radiology, University Hospitals of Morecambe Bay NHS Foundation Trust, Barrow-in-Furness, UK.
Br J Radiol. 2016 Aug;89(1064):20160249. doi: 10.1259/bjr.20160249. Epub 2016 Jun 8.
: The aim of this work was to assess the impact of greyscale inversion on nodule detection on posteroanterior chest X-ray images. Previous work has attempted this, with no consensus opinion formed. We assessed the value of "fast-flicking" between standard and inverted display modes for nodule detection.
: Six consultant radiologists (with 5-32 years' reporting experience) completed an observer task under the free-response paradigm. An anthropomorphic chest phantom was loaded with 50 different configurations of simulated nodules (1-4 nodules per case) measuring 5, 8, 10 and 12 mm in spherical diameter; each configuration represented a single case. In addition, 25 cases contained no nodules. Images were displayed in three modes: (i) standard, (ii) inverted and (iii) fast-flicking between standard and inverted display modes. Each observer completed the study in a different order of display (i, ii, iii) using a calibrated 5-megapixel monitor. Nodules were localized with mouse clicks and ratings assigned using a 1-10 discrete slider-bar confidence scale. Rjafroc (Pittsburgh, PA) was used for data analysis; differences in nodule detection performance were considered significant at 0.05.
: The observer-averaged weighted jackknife alternative free-response receiver-operating characteristic figures of merit were 0.715 (standard), 0.684 (inverted) and 0.717 (fast-flicking). Random-reader fixed-case analysis revealed no statistically significant difference between any treatment pair [F(2,8) = 1.22; p = 0.345].
: No statistically significant difference in nodule detection was found for the three display conditions.
: We have investigated the impact of fast-flicking between standard and inverted display modes for the detection of nodules. We found no benefit.
本研究旨在评估灰度反转对后前位胸部X线图像中结节检测的影响。此前已有相关研究尝试，但未形成共识。我们评估了在标准显示模式和反转显示模式之间“快速切换”对结节检测的价值。
六位放射科顾问医师（报告经验为5至32年）在自由反应范式下完成了一项观察任务。一个仿真人体胸部模型加载了50种不同配置的模拟结节（每个病例1至4个结节），结节的球形直径分别为5毫米、8毫米、10毫米和12毫米；每种配置代表一个病例。此外，25个病例中没有结节。图像以三种模式显示：（i）标准模式，（ii）反转模式，（iii）标准显示模式和反转显示模式之间的快速切换模式。每位观察者使用校准后的500万像素显示器，以不同的显示顺序（i、ii、iii）完成研究。通过鼠标点击定位结节，并使用1至10的离散滑块条置信度量表进行评分。使用Rjafroc（宾夕法尼亚州匹兹堡）进行数据分析；结节检测性能的差异在0.05水平被认为具有显著性。
观察者平均加权留一法替代自由反应接收器操作特征品质因数在标准模式下为0.715，反转模式下为0.684，快速切换模式下为0.717。随机读者固定病例分析显示，任何治疗组对之间均无统计学显著差异[F(2,8) = 1.22；p = 0.345]。
三种显示条件下在结节检测方面未发现统计学显著差异。
我们研究了标准显示模式和反转显示模式之间快速切换对结节检测的影响。我们发现并无益处。
