低剂量CT扫描对儿童上颌骨埋伏阻生牙图像质量影响的探讨

Discussion for image quality of low dose CT scan in children maxilla unerupted teeth

目的探讨儿童上颌骨低剂量CT扫描的可行性及方法。方法选择106例上颌骨埋伏阻生牙患者,随机分为4组,用标准条件及三种低剂量条件分别扫描,应用多平面重建法(MPR)、最大密度投影法(MIP)、容积重建(VR)3种方式对图像进行重建,不同图像相互比较,对上颌骨的图像质量进行评价。结果 180 mA、150 mA、80 mA几种低剂量扫描图像,与标准图像比较,虽图像噪声略有增加,但均能清晰地显示埋伏组生牙与邻牙关系。结论低剂量扫描与常规扫描比较,图像质量无明显差异,均能满足临床诊断基本要求。

Objective To study the feasibility and method low dose CT scanning in children maxilla unerupted teeth. Methods A total of 106 patients were randomly divided into 4 groups, scanning with the standard conditions and three kinds of low dose conditions, and compared each other with images of multiple levels reconstruction （MPR）, maximum density projection（MIP）, and volume render（VR）, evaluated the image quality. Results Compared with the standard images, although the image noise increases, but all the images scanning with 180 mA, 150 mA, 80 mA could clearly show the teeth and adjacent teeth relationship. Conclusion Low dose scanning and conventional scanning have no obvious difference, image can meet the basic requirements for clinical diagnosis.