16层CT低剂量成像诊断小儿气道异物

16-slice MDCT with Low-dose Technique in Diagnosing Children Airway Foreign Bodies

目的:评价16层螺旋CT低剂量扫描及运用多种重建技术对小儿气道异物的诊断价值。材料和方法:对48例气道异物患儿采用低剂量胸部扫描,参数为:120kV,30mAs,螺距0.75,重建层厚1mm,重建间隔0.5mm。轴位原始数据传至工作站分别行MPR、MinIP、VR及CTVE重建成像。结果:异物位于气管4例,支气管44例。其中金属异物5例,非金属异物43例,经气管镜取出异物49处。CT对气管异物诊断准确率为100%,对主支气管、叶及段支气管异物的诊断准确率为97.8%。结论:采用低剂量扫描可大幅度减少X线对小儿的辐射,而图像质量可达到常规剂量扫描的效果,多种成像技术结合运用,可清楚显示异物的部位、形态、大小及肺内的阻塞性病变,对临床治疗有重要的指导价值。

Purpose： To evaluate the diagnostic value of low - dose scan and multimode image recon- struction by 16- slice MDCT for children＇ s airway foreign bodies. Materials and Methods： 48 patients with airway foreign bodies underwent thoracic low - dose scan with the following parameters： 120kV, 30mAs, pitch0.75, reconstruction collimation 1 nun and reconstruction interval 0.5 nun. Then the original axial data were transferred to workstation for imaging reconstruction by MPR, MinIP, VR and CTVE respectively. Results： Foreign bodies of 4 cases were detected in trachea, 44 in bronchus; 5 cases were found with metal foreign bodies, 43 with non - metal ones. 49 bodies were extracted through bronchoscope. The diagnostic accuracy is 100% for foreign bodies in trachea, and 97.8% in primary, segmental and lobal bronchi.Conclusion： Adoption of low - dose scan can greatly reduce the radiation of X - ray to children and ensure the quality of image as regular dose scan does. Combined application of multiimaging techniques can clearly display the location, shape, size of foreign bodies and lung occlusion as well, indicating it is of high value for clinical treatment.