全脑CT灌注成像在侧枝循环评估中的辐射剂量和临床应用价值  

Radiation dose and clinical value of whole⁃brain CT perfusion imaging in the assessment of collateral circulation

作　　者：刘青[1] 李伟粟 王娇娇 张宗望 徐士杰 韩锦涛 许建辉[1] Liu Qing;Li Weisu;Wang Jiaojiao;Zhang Zongwang;Xu Shijie;Han Jintao;Xu Jianhui(Department of Radiology,Tianjin Beichen Hospital,Tianjin 300060,China;United Imaging Healthcare,Shanghai 201800,China)

机构地区：[1]天津市北辰医院放射科,天津300060 [2]上海联影医疗科技股份有限公司,上海201800

出　　处：《中华放射医学与防护杂志》2024年第1期47-52,共6页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的探究一站式全脑CT灌注成像(CTP)在急性缺血性脑卒中(AIS)患者侧枝循环评估中的辐射剂量和临床应用价值。方法回顾性收集32例AIS患者的全脑CTP图像和数字减影血管造影(DSA)图像。通过固定管电压(100 kVp)、分段设置管电流的方式优化CTP采集同时获得的CT血管成像(CTA)的图像质量。记录容积剂量指数(CTDIvol)、剂量长度乘积(DLP), 计算有效剂量(E), 与文献进行比较。患者核心梗死区域和对侧半脑健康区域脑灌注参数比较采用配对t检验。一名放射科医师分别基于CTP、多时相CTA联合CTP两种模式, 采用5分法评估患者侧枝循环状态。由另外一名放射科医师基于DSA图像采用同样的5分法进行评分。以DSA结果作为参照, 计算其余方法评估结果的准确率。评分结果的相关性采用Pearson相关系数分析, 一致性采用Kappa分析。结果平均CTDIvol为184.18 mGy, 和文献报道相当(184.19 mGy)。相较于文献报道的CTP和CTA联合扫查, 一站式全脑CTP检查的平均有效辐射剂量降低了39% (6.1vs. 10 mSv)。核心梗死区域和对侧半脑健康区域脑血容量(CBV)、脑血流量(CBF)、平均通过时间(MTT)、达峰时间(TTP)和残余函数达峰时间(Tmax)的差异均有统计学意义(t=-6.11、-7.47、8.58、12.34、10.05, P<0.01)。CTP和DSA的评分相关系数为0.95 (95%CI:0.89~0.97, P<0.01), 多时相CTA联合CTP和DSA的评分相关系数为0.98 (95%CI:0.96~0.99, P<0.01)。DSA CTP评估结果的Kappa值为0.64 (t=7.53, P<0.01), 与多时相CTA联合CTP评估的Kappa值为0.88 (t=9.99, P<0.01)。CTP评估侧枝循环的准确率为71.9%, 多时相CTA联合CTP评估的准确率则为90.6%。结论固定管电压、分段设置管电流的一站式全脑CTP能够同时提供可靠的CTP和多时相CTA, 合理降低患者辐射剂量。借助多时相CTA联合全脑CTP能够准确判断颅内血管有无侧枝循环及脑组织状态, 有助于临床中AIS患者诊断和治疗方案的制定。Objective eTo assess the radiation dose and clinical value of"one-stop"whole-brain CT perfusion(CTP)imaging in the evaluation of collateral circulation for patients with acute ischemic stroke(AIS),regarding the digital subtraction angiography(DSA)as the reference.Methods This retrospective study included 32 AIS patients,for whom both CTP and DSA were obtained<24 h since onset.All CTP scans were acquired in whole⁃brain volume perfusion mode using a 320⁃row CT with the phase⁃specific settings of tube currents to optimize the image quality of CTA images,where multiple⁃phase(mp)CTA images were extracted from the CTP data in post⁃processing.The volume CT dose index(CTDIvol),dose length product(DLP),and effective dose were compared to those reported in previous studies.The perfusion parameters of the infarct lesions and their contralateral regions were compared using the paired t⁃tests.One radiologist scored the collateral circulation with only the CTP and with the CTP plus mp⁃CTA using a 5⁃point scale.Another radiologist performed the same evaluation on the DSA.The diagnostic accuracy was calculated referring to the result based on DSA.The scores were analyzed using the Pearson correlation coefficient.The agreement of scores was quantified with the Kappa test.Results The mean CTDIvol was 18418 mGy,which was comparable to the result of a previous study(18419 mGy),and the mean effective dose was reduced 39%compared to that reported in the literature for combined CTP and CTA scanning(6.1 vs 10 mSv).There were statistically significant differences in cerebral blood volume(CBV),cerebral blood flow(CBF),mean transit time(MTT),transit time to peak(TTP),and time⁃to⁃maximum(Tmax)between the infarct lesions and their contralateral regions(P<0.01).The scores between CTP and DSA were significantly correlated(r=0.95,P<0.01),as well as the scores between CTP plus mp⁃CTA and DSA(r=0.98,P<0.01).The Kappa value was 0.64(t=7.53,P<0.01)between CTP and DSA,while it increased to 0.88(t=9.99,P<0.01)for CTP plus mp⁃C

关 键 词：脑卒中 全脑灌注 辐射剂量 CT血管成像 

分 类 号：R144.1[医药卫生—公共卫生与预防医学]