目的 探讨螺旋CT低剂量扫描对 儿童肺结核的诊断价值。方法 临床纳入 疑似肺结核患儿共179例，首先对所有儿 童进行常规剂量智能化自动跟踪80MA100MA螺旋CT扫描，然后间隔2天后对1-7 岁儿童选择20MA、8-14岁儿童选择30MA 进行低剂量扫描。将不同剂量的CT片在 不显示毫安量参数的情况下混放，并进 行盲法图像质量比较。结果 1-7岁儿童 常规剂量CT图像总分为93.4分，低剂量 20MA CT图像质量总分为74.1分，差异有 显著性(P＜0.05)；8-14岁儿童常规剂量 CT图像总分为94.8分，低剂量30MA CT图 像质量总分为89.0分，差异无显著性(P＞ 0.05)；两组诊断准确率差异无显著性(P ＞0.05)。结论 选择30MA低剂量螺旋CT扫 描，能够作为常规性诊断不同年龄儿童的 肺结核，CT图像质量能够达到影像学诊断 要求，并可以最大程度上减少辐射剂量； 20MA低剂量螺旋CT扫描后图像质量较差， 一般不作为常规性儿童肺结核诊断。

Objective To study the diagnosis value of low-dosage spiral CT scanning in the children's pulmonary tuberculosis. Methods 179 children with suspected pulmonary tuberculosis were selected. All the children received the intelligent and automatic tracking based on 80MA-100MA of regular dosage spiral CT scanning. After 2 days, 20MA of low-dosage scanning was applied on children aged from 1 to 7 and 30MA of low dosage scanning was applied on children aged from 8 to 14 years old. Based on the different dosages, CT images were mixed without the milliampere parameters displayed so as to compare the image quality. Results For children aged from 1 to 7, the total score based on the regular dosage was 93.4, based on 20MA of CT scanning, the total score was 74.1 (P ＜0.05), for children aged from 8 to 14, the total score based on the regular dosage was 94.8 scores, based on 30MA of CT scan, the total score was 89.0 (P＞0.05), the diagnosis accuracy rate of two groups were not significantly different (P＞0.05). Conclusion The selection for 30MA of low-dosage spiral CT scanning is applicable to do conventional diagnosis of children with tuberculosis at different ages, the image quality can meet the imaging diagnosis requirements and minimize the radiation dosage. The 20MA of lowdosage spiral CT scanning has a poor image quality and generally don't serve as the conventional diagnosis of children with tuberculosis.