低剂量螺旋CT扫描及后处理对小儿气管支气管异物的诊断价值

Value of low-dose SCT and postprocessing technique in the diagnosis of tracheal and bronchial foreign bodies in children

目的:探讨低剂量螺旋CT扫描及后处理技术对气管支气管异物的诊断价值。方法:对103例气道异物患儿行螺旋CT扫描,CT扫描参数为120kV,40～80mA,层厚7mm,间距7mm,螺距3,扫描后进行层厚3mm,间隔1.5mm内插式重建,对获得的数据进行图像后处理,后处理技术包括多平面重建(MPR)、最小密度投影(MinP)、表面遮盖法重建(SSD)、CT仿真支气管内窥镜(CTVB)。与支气管内窥镜进行比较。结果:103例气管支气管异物均获得满意的后处理图像,螺旋CT及后处理技术的诊断准确性为100%,异物定位与支气管镜检相符97.1%。其中MPR(包括CPR)在显示异物本身和局限性气管、支气管阻塞最好。结论:小儿气管支气管异物可用螺旋CT低剂量扫描,但不能用单一的后处理技术,应该将轴位和多种后处理技术结合起来,综合分析。本病的直接征象是显示异物本身,而局限性支气管阻塞需结合其他征象才能确诊。

Objective: To explore the value of low-dose SCT and postprocessing technique in the diagnosis of tracheal and bronchial foreign bodies in children.Methods: SCT were performed in 103 children with airway foreign bodies.The SCT scan parameters included 120kV,40～80mA,7mm thickness and intervals of slices.Then the inserted constructions with 3mm thickness and 1.5mm interval of slices and postprocessing were made.The postprocessing technique included multiplanar reconstructions(MPR),minimum intensity projection(...