摘要
目的:探讨DoseRight技术条件下探测器宽度与螺距的不同组合对气道异物儿童CT检查辐射剂量及图像质量的影响,在保证图像质量的同时降低辐射剂量。方法:前瞻性连续选取在医院行气道CT检查的299例1~3岁患儿,按照探测器宽度与螺距数据参数的不同,将患儿分为128×0.625 mm探测器+1.15螺距组(103例)、128×0.625 mm探测器+0.4螺距组(97例)和64×0.625 mm探测器+1.15螺距组(99例),采用DoseRight技术,管电压80 kV,剂量指数(DRI)为17,记录容积CT剂量指数(CTDIvol)及剂量-长度乘积(DLP),并对其进行对比分析,对所得图像进行主观及客观评价并对比分析。结果:3组患儿CTDIvol和DLP间的比较差异均有统计学意义(F=31.4,F=29.6;P<0.05),64×0.625 mm探测器+1.15螺距组小于其他两组,LSD-t检验差异有统计学意义(P<0.01),余两组比较差异无统计学意义。结论:在DoseRight技术条件下适当采用较窄探测器宽度及较大螺距进行儿童气道CT检查能够保证图像质量,并可降低辐射剂量。
Objective:To explore the effects of different combination of coverage and pitch of detector on the radiation dose and image quality of CT examination for airway foreign body of children under the condition of DoseRight technique so as to ensure the image quality and reduce the radiation dose.Methods:299 children 1-3 years of age who underwent computed tomography(CT)examination on airway were prospectively selected.And they were divided into 128×0.625 mm detector coverage and 1.15 pitch group,and 128×0.625 mm detector coverage and 0.4 pitch group,and 64×0.625 mm detector coverage and 1.15 pitch group according to different parameters of detector coverage and pitch.And the DoseRight technique and 80 kV tube voltage were adopted,and the dose right index(DRI)was 17,and CT volume dose index(CTDIvol)and dose-length product(DLP)were recorded and were further compared and analyzed.And all of images were evaluated subjectively and objectively,and were compared and analyzed.Results:The differences of CTDIvol and DLP among three groups were statistically significant(F=31.4,F=29.6,P<0.05).The CTDIvol and DLP of 64×0.625 mm detector coverage and 1.15 pitch group were significantly less than those of other two groups(P<0.01),while the differences of CTDIvol and DLP between other two groups were not statistically significant.Conclusion:Under the condition of DoseRight technique,it can ensure the image quality and reduce the radiation dose to use a narrower detector coverage and larger pitch for CT examination on airway of children.
作者
姚艾杰
边传振
高峰
王颖
YAO Ai-jie;BIAN Chuan-zhen;GAO Feng(Department of Radiology,Children's Hospital of Nanjing Medical University,Nanjing 210000,China.)
出处
《中国医学装备》
2020年第7期30-34,共5页
China Medical Equipment
关键词
儿童
气道异物
探测器宽度
螺距
CT图像质量
Child
Airway foreign body
Detector coverage
Pitch
Image quality of CT
