螺旋CT低剂量扫描及多平面重建在小儿气管支气管异物中的应用

Value of low-dose spiral CT and multiple planar reconstruction in diagnosing airpassage foreign body for children

目的探讨螺旋CT低剂量扫描及多平面重建(MPR)图像后处理技术在小儿气管、支气管异物中的诊断价值。方法回顾性分析我院经支气管内窥镜检取异物的31例小儿气管支气管异物患儿术前影像学资料。31例患儿X线诊断物不明确。螺旋CT扫描须用管电压120kV,管电流30～40mA,时间1s,螺距0.75,层厚3mm,重建间隔1.5mm及MPR图像后处理技术。结果低剂量螺旋CT及MPR图像显示异物呈结节状附着或嵌顿于气道内导致局段气道连续性中断27例,异物阻塞肺叶或肺段形成不张4例。与支气管镜检结果对照,其对中心气道异物诊断准确性为100%,3级以上支气管异物诊断准确性为96.77%。结论螺旋CT低剂量扫描及MPR图像后处理技术可明确诊断小儿气管、支气管异物,并可作为支气管镜检前的筛查。确定手术路径。后诊断中具有重要的临床应用价值。

Objective To investigate value of low-dose spiral CT and multiple planar reconstruction (MPR) in diagnosing airpassage foreign body for children for children. Methods 31 children who underwent tracheoscopy for taking out foreign body in trachea and bronchi were reviewed with their preoperative imaging data. X-ray was unable to identify the foreign bodies. Parameters for spiral CT were at tube voltage 120 kV, tube current 30-40mA, time 1s, helical pitch 0.75, thickness of layer 3mm, and reconstruction interval 1.5mm. Post-imaging treatment used MPR. Results low dose spiral CT and MRP showed foreign bodies attached or choked in air passage causing interrupted airpassage in 27 children; lobe obstruction or atelectasis in 4 children. Compared with tracheoscopy findings, correctness rate for diagnosing foreign body in major air passages was 100%, and for bronchi higher than the third class was 96.77%. Conclusion Low-dose Spiral CT and MPR are able to clearly diagnose foreign body in air passage, useful in pre-tracheoscopy screening, determining operational method.