CT低剂量扫描及后处理技术在婴幼儿气管非金属异物中的应用探讨

目的　探讨多层螺旋CT低剂量扫描及其后处理技术在婴幼儿气管非金属异物中的诊断价值。方法　分析我院收治的48例被确诊为婴幼儿气管非金属异物患者的CT影像学资料。128层螺旋CT扫描参数为100 kV，30～40 mA，层厚0.9 mm，螺距1.4，对获得的数据进行多平面重建（multiplanar reconstruction，MPR）、最小密度投影（minimum intensity projection，Min-IP）及CT仿真内镜（CT virtual endoscopy，CTVE）与支气管内镜结果对比分析。结果　48例CT低剂量扫描图像全部符合诊断要求。CT对异物的检出率和支气管内镜无统计学差异，3种后处理技术中MPR与Min-IP无统计学差异，MPR、Min-IP分别与CTVE比较有显著性差异，MPR和Min-IP诊断的准确性高于CTVE。结论　螺旋CT及后处理技术能准确诊断及定位婴幼儿气管内的非金属异物，清楚显示出异物的大小和位置，具有很高的实用价值。

Low dose CT scanning and post-processing technique in the application of infant non-metal foreign bodies in trachea

OBJECTIVE Discuss the diagnostic value of MDCT low-dose scan and post-processing technique in the infant non-metal foreign bodies in trachea. METHODS The CT imaging data of 48 cases in our hospital diagnosed as infant non-metal foreign bodies in trachea were analyzed. The scanning parameters of 128 slice spiral CT were 100 kV, 30-40 mA, layer thickness 0.9 mm, pitch 1.4. The obtained CT data were processed for multiplanar reconstruction (MPR), minimum density projection (Min-IP) and CT simulation endoscopy (CTVE). The results of CT and bronchial endoscopy were compared. RESULTS All of the low dose CT scanning image of the 48 cases met the diagnostic requirements. The detection rate of CT and bronchial endoscopy for foreign bodies had no statistical difference. For the three kinds of post-processing techniques, the detection rate of MPR and Min-IP had no statistical difference, but the detection rate of MPR and Min-IP were higher than that of the CTVE. CONCLUSION Spiral CT and postprocessing technique can accurately diagnose and localize the infant non-metal foreign bodies in trachea. It can clearly show the size and location of the foreign bodies in trachea. It has great practical value.