由于煤矽肺早期X线变化较细微,结节数量较少及纤细不易看到,因此煤矽肺早期诊断存在一定困难。高仟伏及断层摄片对一般矽肺的早期诊断要较常规X线胸片为佳,但因高仟伏摄片由于电压过高(120～140kV),X射线的穿透力太强,对细网及细小结节的显示反而显得数量减少和模糊不清,断层摄片也不能把细小结节暴露出来,因此,我们把电压降到次高仟伏90kV,并和其他各种不同投 Due to the early X-ray changes of coal silicosis is subtle, the number of nodules is small and slender is not easy to see, so there are some difficulties in the early diagnosis of coal silicosis. High thousands of volts and tomography on the general diagnosis of silicosis than the conventional X-ray chest is better, but due to high-kV film due to over-voltage (120 ~ 140kV), X-ray penetration is too strong, Fine mesh and fine nodules appear instead to be diminished in volume and obscure, and tomographs can not expose small nodules, so we drop the voltage to the next kV of 90 kV and compare it with a variety of other