儿童鼻咽部形态学的低剂量多层螺旋CT研究

目的利用低剂量多层螺旋CT多平面重建（MPR）技术探索儿童鼻咽部气道大小及鼻咽部顶后壁软组织厚度。方法收集2005年5月至2007年10月来我院检查鼻咽部儿童的CT扫描图像，选择其中符合条件的73例进行回顾性分析。为研究其鼻咽腔形态学特点，测量了儿童鼻咽顶后壁软组织厚度（A值）及鼻咽部矢状径（N值），并计算二者比值。根据儿童年龄分为两组：A组1～7岁（n=42），B组8～14岁（n=31）。结果所有儿童正常鼻咽部气道矢状位均呈镰刀形，周围脂肪间隙清晰，后缘光整连续。A组及B组鼻咽顶后壁软组织厚度（A值）均数大小分别为9．23±4．85mm和9．56±4．74mm；MN值范围两组分别为0．2～0．58和0．21～0．6；两组间没有统计学差异。结论低剂量多层螺旋CTMPR显示，1～14岁健康儿童鼻咽腔矢状位呈弓向上镰刀形，边缘光整，周围脂肪间隙清晰，A／N≤0．6。

Research into the morphology of childrens' nasopharngeal airway with LD MSCT

Objective To investigate the morphology of healthy children＇s nasopharyngeal airway by using low dose muhislice spiral computed tomography（LD-MSCT）with multiplanar reconstruction（MPR）.Methods CT data of 73 healthy children who underwent LD- MSCT MPR examinations of nasopharyngeal part in our hospital from May 2005 to October 2007 were collected and analyzed retrospectively.The soft tissue thickeness of nasopharyngeal top back wall（A value）and the sagittal diameter of nasopharyngcal airway（N value）were measured for each case.All children were divided into below tow groups according to the age：A group （n=42） aged 1 to 7 years and B group （n=31） aged 8 to 14 years.The ratio of average A value and N value（A/N）in the two groups was calculated respectively.Results On sagittal section view,the nasopharyngeal airway of all children appeared as sickle-form,clear peripheral fat space, continued and smooth posteriror margin.The mean A value of A and B group was 9.23＋/-4.85 mm and 9.54＋/-4.74 nun,respectively,while A/N of A and B group ranged 0.2 to 0.58 and 0.21 to 0.6,respectively,there was not statistical difference between two groups.Conclusion LD-MSCT MPR demonstrate that,on sagittal section view,the nasopharyngeal airway of all children appear as sickle-form with smooth margin and A/N is equal or less than 0.6.