低剂量螺旋CT在婴幼儿脑外伤诊断中的应用

The Application of the Low-dose Spiral CT in the Diagnosis of Infant Brain Injury

目的:探讨婴幼儿头颅检查时螺旋CT扫描的最适低剂量。方法:对临床怀疑颅脑外伤需行CT检查的婴幼儿120例,随机分为6组,每组20例,采取逐次降低管电流方法,分别获得100 mA标准剂量影像和90、80、70、60、50mA 6种低剂量影像,根据影像质量进行评价,找出满足诊断需求的最适管电流量后进行临床应用。同时记录扫描时随机自动显示的剂量指标即容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)。结果:①除50mA条件下6例图像质量评价结果为差外,其他低剂量图像都能达到诊断要求。当管电流降低至50mA时,图像质量分级以一般为主。管电流为60、70、80 mA时图像质量以较好、好为主。②临床实际应用管电流60mA扫描时,与常规剂量比较CTDIvol下降了39.97%、DLP下降了40.00%。结论:婴幼儿头颅CT检查时,管电流为60 mA所得的图像即可满足临床诊断,又可明显降低婴幼儿患者的辐射剂量。

Objective： To explore optimum low doses of the infant skull checks in spiral CT scan. Methods： 120 cases of clinical suspicion infant brain trauma need a CT scan, were randomly divided into 6 groups （n = 20） using successive lower tube current, 100mA standard dose images and 90, 80, 70, 60 50mA six kinds of low - dose images were evaluated according to the quality of the image to identify the optimum tube current capacity to meet the diagnostic needs of clinical application. At the same time the record scan random automatically display dose indicators that volume CT dose index （CTDIvol）, dose- length product （DLP）. Results：O In addition to the six cases under 50mA conditions image quality evaluation results worse, other low - dose images to achieve diagnostic requirements. When the tube current is reduced to SOMA, image quality grading mainly in general. The tube current 60, 70, 80 mA when the image quality is a good, good mainly. （~）Clinical practical application tube current 60mA scan, compared with conventional dose CTDIvol dropped was 39.97%, down 40.00% of DLP. Conclusion： Infant head CT examination, the tube current of 60mA from the image to meet the clinical di- agnosis, but also significantly reduce the patient radiation dose infant.