螺旋CT常规剂量与低剂量扫描检出肺结节的对比研究

目的通过螺旋CT肺部常规剂量与低剂量扫描的对比分析，评价低剂量扫描检出肺结节的价值。方法对40例肺内结节患者分别行常规剂量螺旋CT（160mA，螺距1．0，层厚5mm）扫描及低剂量螺旋CT（40mA，螺距2．0，层厚5mm），采用双盲法对结节的数目、大小及结节的细节征象（分叶、毛刺、胸膜凹陷、钙化、空洞及支气管气像）进行分析。结果低剂量CT扫描检查对结节的检出及细节征象与常规剂量扫描检查均无明显差异。但低剂量扫描剂量当量（CTDlw）仅为常规扫描的12．4％。结论低剂量螺旋CT与常规剂量螺旋CT对肺结节的显示相仿，可用于高危人群肺癌筛查。

Comparative Study of Low Dose and Normal Dose Spiral CT Scan in Pulmonary Sarcoidosis Screening

Objective To evaluate the value of low dose spiral CT scan via the comparative research of low dose and normal dose spiral CT scan in the pulmonary sarcoidosis screening. Methods A total of 40 ca- ses with pulmonary nodule were received spiral CT scan with normal-dose scan （ 160 mAs, pitch 1.0, thickness 5 mm） and low-dose scan （40 mAs, pitch 2.0, thickness 5 rnm）. The magnitude, size and details （leaf, glit- ches, pleural indentation, calcification, pulmonary cavity and air bronchogram） of pulmonary sarcoidosis were analyzed by double blind method. Results There is no distinct difference in detection and details of pulmo- nary nodule screening between low dose scan and normal dose scan. But CTDlw of low-dose scan was 2.9 mGy and only accounted for 12.4% of normal-dose scan. Condusion The detection effect of low-dose spiral CT scan is similar to normal-dose scan in pulmonary sarcoidosis screening, thus it can be applied to lung cancer screening among high risk group.