双低剂量联合增加扫描时间间隔对头颅320排CT灌注的灌注参数和放射剂量影响分析  

Effects of Low Dose Combined with Increasing Scan Time Interval on Perfusion Parameters and Radiation Dose in Head 320-row CT Perfusion

作　　者：向勇生 徐卫国[1] 史鹰勤[1] 于吉利 XIANG Yong-sheng;XU Wei-guo;SHI Ying-qin;YU Ji-li

机构地区：[1]同济大学附属同济医院医学影像科

出　　处：《中国医学计算机成像杂志》2019年第3期311-315,共5页Chinese Computed Medical Imaging

摘　　要：目的:研究低管电压、低管电流联合增加扫描时间间隔对患者320排头颅CT灌注放射剂量及灌注参数值的影响。方法:回顾性分析于我院行全脑动态增强扫描的20例患者的影像资料,通过甲乙两组各10例,分别采用常规灌注扫描和低剂量灌注扫描,并通过两组的灌注参数值和图像质量指标之间的差异来分析验证本低剂量扫描方案的可行性。结果:通过计算分析可得到灌注参数值之间的比较结果,甲组和乙组在枕顶叶和基底节区测得的CBF、CBV、TTP、MTT值之间无明显的统计学差异(P>0.05)。两组图像质量的客观指标CNR、SNR、CV、SD之间也无明显的统计学差异(P>0.05),两组图像均能够满足诊断需要。乙组剂量是甲组的27.31%,剂量显著降低。结论:本实验通过适当降低管电压和管电流,联合增加扫描间隔,减少扫描次数的方法,实现了辐射剂量明显降低,同时又保证了灌注图像的质量和参数的准确性,具有可行性和重复性。Purpose: To investigate the effects of low-voltage and low-tube current combined with increasing scan interval on the radiation dose of 320-slice perfusion CT. Methods: We retrospectively analyzed the imaging data of 20 patients who underwent whole brain dynamic enhanced scan in our hospital. We divided the patients into two groups (group A and group B). These two groups used routine perfusion scan and low-dose perfusion scan respectively. The differences between the perfusion parameters and image quality of the two groups were analyzed to verify the feasibility of this low-dose scan protocol. Results: There was no significant difference between the relative perfusion values in groups A and group B (P>0.05). There were no significant statistical differences between the two groups of image quality indicators (CNR, SNR, CV and SD)(all P>0.05). The effective dose in group B was 27.31% of that in group A, and the dose was significantly reduced. Conclusion: In this experiment, by appropriately reducing the tube voltage and tube current, jointly increasing the scan interval and reducing the number of scans, a significant reduction in the radiation dose was achieved. Meanwhile, the quality of the perfusion images and the accuracy of the parameters were feasible and repeatable.

关 键 词：双低剂量 扫描时间间隔 脑CT灌注 

分 类 号：R814.42[医药卫生—影像医学与核医学]