电焊烟尘与矽尘所致肺部异常的早期HRCT表现的对比研究

目的比较电焊烟尘与矽尘所致肺部的早期HRCT表现，探讨其病理学意义。方法对456例焊尘及矽尘作业者进行肺部HRCT检查，男性443人，女性13人，年龄22-75岁，平均年龄44．0岁，工龄0．5-29年，平均工龄13．1年。采用GENX／i螺旋CT扫描仪，深吸气末HRCT采用层厚1-2mm，间隔10mm，轴面扫描，扫描速度1s／r，高分辨率重建，扫描范围自肺尖至横膈。分析HRCT的异常表现，观察肺窗窗宽为1200HU，窗位为－700HU，纵隔窗窗宽为400HU，窗位-30HU。结果456例粉尘作业者中346例可见不同程度异常。早期肺部异常主要表现为小叶内分支状线影增多（187，41．01％），电焊工肺部表现较矽尘作业者更加显著：51例（11．18％）可见小叶间隔增厚，矽尘较焊尘更易出现小叶间隔增厚（χ^2=10．109，P=-0．003）；82例（17．98％）可见边缘清晰结节，焊尘结节分布相对较均匀，大小一致，小叶中心分布，密度相对较低，而矽尘结节密度较高，大小不均匀，可合并肺结构及血管束的扭曲和变形：47例（10．31％）表现为磨玻璃密度结节，位于小叶中心，其中42例见于焊尘作业者。29（6.36％）例肺内可见磨玻璃影，其中18例见于焊尘。72例（15．79％）可见不同程度肺气肿改变，矽尘作业者肺气肿明显多于电焊工（χ^2=24．206，P=-0．000）。结论不同粉尘的致纤维化作用的不同，HRCT有助于对粉尘的致纤维化进行早期评估。

Comparative study of the early lungs manifestations of the electric welding and the silicon dioxide dust induced on HRCT

Objective To compare with the electric welding and the silicon dioxide dust induced lungs＇ early HRCT performance, discusses its pathology significance. Methods Four hundreds and fifty-six workers with a 0.5 to 29 years history of dust exposure underwent HRCT scanning. The extent of abnormalities was detected. The CT scans were obtained with a model Hispeed NX/i scanner （GE Medical Systems）at 10-mm intervals by using 2mm collimation. The scans were obtained during breath hold after deep inspiration, from the apex of the lungs to the base of the diaphragm. Patients were examined in the supine position. Targeted raw data reconstructions of each lung were performed with a high-spatial-frequency reconstruction algorithm and photographed at a level of-700 HU and a window width of 1, 200 HU. The CT scans were assessed independently by three observers. Results The 346 cases among 456 cases could be seen abnormal to varying degrees. Predominant HRCT findings were branching linear structure （187, 41.01%）, lobular septal thickening （51,11.18%）, small nodules （82, 17.98%）, poorly-defined ground-glass attenuation centrilobular micronodules （47, 10.31%）, patch of ground-glass attenuation （29, 6.36%）, emphysema （72,15.79%）. Lobular septal thickening and distortion of lung architecture could be seen commonly in silicosis than arc welder＇ s pneumoconiosis （P〈0.05）. Emphysema could be depicted fewer in arc welder＇ s than in silica dust （χ^2 = 24.206, P〈0.05）. Conclusion Different dust may result varying degrees of lung fibrosis, HRCT is to contribute to early assessment of fibrosis.