目的 研究低剂量螺旋CT扫描 技术在成人肺结核诊断中的价值。方 法 选择150例肺结核患者应用完全随机 化法分为2组，分别采用常规剂量及低 剂量扫描方式。采用Philips64排螺旋CT 机，常规剂量扫描管电流230mA，低剂量 扫描依据BMI的不同选择不同管电流： BMI≤18.5采用20mA；18.5＜BMI＜24.9 采用30mA；BMI≥25采用40mA。比较两方 式对横断面、冠状面及病灶图像质量的 影响。结果 肺窗、纵膈窗横断面图像 质量在两种扫描方式间具有一致性，肺 窗：P=0.539；纵膈窗：P=0.235。冠状 面图像质量在两组间无统计学差异(P＞ 0.05)。两种扫描方式所得肺结核CT影 像特征比较，结果8项特征的P值均大于 0.05。将两组受检者的辐射剂量作两样 本均数t检验，P值均远小于0.01。比较 两组受检者的平均噪声水平，P＜0.01。 结论 低剂量扫描技术在成人肺结核诊断 及随访中的常见影像征象的检测效果与 常规剂量扫描无显著差异。低剂量扫描 技术显著降低了受检者的辐射剂量。

Objective To investigate the diagnosis value of low-dose spiral CT scanning technology in adullt pulmonary tuberculosis. Methods Choose 150 cases of tuberculosis patients, and divide them into two groups using the completely randomized method. Then adopt conventional-dose and low-dose scanning methods in these patients. Philips 64-slice spiral CT is adopted and electric current of conventional-dose scanning tube is 230mA. According to different BMI, different electric current is available: BMI≤18.5, 20mA, 18.5<bmi<24.9, 30ma.="" 40ma.="" compare="" the="" differences="" between="" cross="" coronal="" planes="" and="" quality="" of="" focuses="" infection="" in="" these="" two="" methods.="" results="" image="" sections="" lung="" window="" mediastinal="" scanning="" methods="" are="" consistent.="" window:="" p="" plane="" groups="" is="" not="" statistics="">0.05). Depented on the comparison of tuberculosis CT images, the P value of eight characteristics are bigger than 0.05. Make two samples of the Radiation dose between the two groups of subjects and take the average test. The result is the P value is more smaller than 0.01. Compared with the average noise level between the two groups, P value is smaller than 0.01. Conclusion There is no significant difference between conventional-dose and low-dose scanning technology in the aspect of adult tuberculosis diagnosis and the detection effect of common imaging sign. As a result, lowdose scanning technology reduces the radiation dose of subjects significantly.