不同分辨力单色液晶显示器对肺小结节检测效能的影响

Influence of monochrome LCDs with different resolutions for the detection performance of pulmonary micro-nodule

目的评价不同分辨力医用单色液晶显示器对胸部DR影像图中直径<10mm的肺小结节检出效能的影响。方法从PACS中在线选取胸部DR影像图87幅,其中确诊图32幅、疑诊图32幅、正常图23幅(均由CT证实),所有结节直径均<10mm。请放射科高、中、低年资医师各3名在3种不同分辨力的显示器上集中进行3次独立读图,对结节有无的评判采用5等分法:肯定有、可能有、不确定、可能无、肯定无,每名医师针对每台显示器上的每幅图像给出信任等级。采用SPSS13.0计算ROC曲线下的面积并进行Z检验。结果使用2MP、3MP、5MP显示器时ROC曲线下的面积随显示器分辨力和医师年资的增高而增高,不同年资的医师使用相同分辨力的显示器或同年资的医师使用不同分辨力的显示器时诊断效能比较差异无统计学意义(P>0.05)。结论在不限制使用图像后处理工具时,使用不同分辨力的显示器检测直径<10mm的结节时诊断效能相当;高年资的医师使用5MP的显示器会得到更多的影像信息;放射科采用高、中、低分辨力显示器相结合组成诊断工作站系统,不同年资医师和不同分辨力显示器之间合理配置,可以提高性价比。

Objective To assess the influence of medical monochrome liquid crystal displays（LCD）with different resolutions for the detection performance of micro-nodules（diameter〈 10 mm）on chest radiograms.Methods Eighty-seven DR chest images that were verified with CT were selected from PACS on-line,including 32 positive images,32 suspected images and 23 normal images.The diameters of all nodules were lower than 10 mm.Three of high-,mid-and low-experienced radiologists who participated in the ROC study interpreted these 87 images using three types of LCDs with different resolutions,respectively.Regarding the presence of nodule,five-point confidence level rating scale was used,i.e.definitely absent,probably absent,possibly present,probably present and definitely present.All observers marked their confidence levels of every image according to the presence of pulmonary nodule on different displays.Software SPSS 13.0 was used for statistical analysis.Results AUC increased with the increasing resolutions and radiologists＇ experiences in 2MP,3MP,5MP displays.For the detection performance of pulmonary nodules（diameter〈 10 mm）,there was no significant difference among different types of displays or different aptitudes of radiologists.Conclusion It＇s equivalent for the detection performance of pulmonary nodule（diameter〈 10 mm）on 2MP,3MP and 5MP medical monochrome LCD when no restriction on the use of image post-processing tools.Highly-experienced radiologist can get the most information when using 5MP display.It is advisable to combine the diagnostic workstation system with high-,mid-and low-resolution monitors,and reasonable equipment scheme between different types of displays and different aptitudes of radiologists could result in better cost-efficacy.