比较数字断层融合与数字X线摄影检出模拟肺结节的能力

Comparison of detection rate for simulated lung nodules between digital tomosynthesis and digital radiography

目的利用仿真体模对比分析数字断层融合(DTS)与数字X线摄影(DR)检出模拟肺结节的能力。方法采用五种规格(直径3、5、8、10、12mm)、三种密度(CT值100、-630及-800HU)的模拟肺结节共15个,先后分别置于体模两肺的上、中、下肺野,形成模拟肺结节共计90个(15个×6)。以常规曝光参数分别进行DTS和DR,由2名放射科医师独立评价DTS及DR对肺结节的检出率;测量DTS的辐射剂量,转换为有效剂量,与文献报道的DR有效剂量进行对比。结果 DTS对模拟肺结节的检出率为78.89%(71/90),DR的检出率为28.89%(26/90),DTS检出率高于DR(P<0.01);对于三种不同密度(CT值100、-630和-800HU)的模拟结节,DTS与DR的检出率差异均有统计学意义(P<0.01)。DTS的有效剂量高于文献报道的DR剂量。结论对于肺结节,DTS较DR具有更高的检出率。

Objective To compare the detection ability of pulmonary nodules for chest digital tomosynthesis （DTS） and digital radiography （DR）by using anthropomorphic chest phantom and simulated nodules. Methods Fifteen simulated nodules with five different diameters （3, 5, 8, 10, 12 mm） and three different densities （100, -630, -830 HU） were placed into the upper, middle and lower lung field of both sides （totally 6 times） for the male anthropomorphic chest phantom, respectively. Then DR and DTS with conventional scan parameters were performed. Two radiologists independently assessed the detection rate of pulmonary nodules. The organic radiations doses were recorded and were converted into effective doses （ED） and compared. Results The detection rate of pulmonary nodule of DTS and DR was 78.89 % （71/90） and 28.89 （26/90）, respectively （P〈0.01）. For detection rate of pulmonary nodule with different densities, there were significant differences between DTS and DR （P〈0. 01）. The mean ED of DTS was 0.65 mSv. Conclusion DTS is superior to DR for relative low-dose detection of pulmonary nodules.