320-DVCT双低技术在肺动脉栓塞诊断中的可行性研究  

320-Row Dynamic Volume CT Using“Double Low”Technique in the Diagnosis of Pulmonary Embolism: A Preliminary Study

作　　者：付小娇[1] 刘芳[1] 高超[1] 马琳莹 李小路 只晓会[1] 张同[1] Fu Xiaojiao;Liu Fang;Gao Chao(Department of Radiology,The Fourth Affiliated Hospital,Harbin Medical University,Heilongjiang 150001,China)

机构地区：[1]哈尔滨医科大学附属第四医院放射科,150001

出　　处：《医学研究杂志》2018年第10期145-149,153,共6页Journal of Medical Research

摘　　要：目的应用320排动态容积CT探究低辐射剂量、低对比剂联合AIDR3D迭代重建技术在呼气末对肺动脉栓塞诊断的可行性。方法将64例疑似肺动脉栓塞患者随机分为A、B两组进行肺动脉CT血管成像(CT pulmonary angiography,CTPA)。A组(n=32)注射对比剂:剂量为36. 53±3. 19ml,浓度为370mgI/ml,流速为4. 55±0. 38ml/s;管电压:100kVp。B组(n=32)注射对比剂:剂量为20ml,浓度为320mgI/ml,流速为4. 0ml/s;管电压:80kVp。采用自动管电流调制(automatic tube current modulation,ATCM)技术联合自适应迭代重建3D(adaptive iterative dose reduction 3D iterative reconstruction,AIDR 3D IR)技术在呼气末对所有患者进行CTPA。扫描结束后,记录患者的对比剂剂量、碘量、CT容积剂量指数(CTDIvol)、计量长度乘积(DLP)、有效剂量(ED)并对图像进行主及客观评价。在轴位图像上测量肺动脉主干及其各级分支的平均CT值。结果比较两组的背景噪声、信噪比(SNR)、对比噪声比(CNR)及主观评价各级肺动脉的平均CT值,差异无统计学意义(P> 0. 05)。当管电压从100kVp(A组)下降到80kVp(B组)时,B组的对比剂剂量、注射速率、碘量及CTDIvol、DLP、ED等参数分别较A组下降了45. 25%、12. 09%、52. 66%、49. 12%、49. 25%和49. 01%,差异有统计学意义(P <0. 05)。结论在呼气末进行低管电压、低对比剂——"双低"联合AIDR 3D迭代重建的CTPA扫描方案能够在准确诊断PE的同时,有效降低辐射剂量。Objective To evaluate the feasibility of low dose radiation and iodine CT pulmonary Angiography(CTPA)using a 320-row dynamic volume CT(320-DVCT).Methods Sixty-four suspected PE patients were randomly divided into two groups.Patients in group A(n=32)were injected 36.53±3.19ml contrast medium(370mgI/ml)with injection rate 4.55±0.38ml/s,and performed CTPA using 100kVp tube voltage.In group B(n=32),patients were received 20ml contrast medium(320mgI/ml)with rate 4.0ml/s and scanned using 80kVp tube voltage.All patients were performed CTPA on 320-row volume CT with automatic tube current modulation(ATCM)and AIDR 3D iterative reconstruction algorithm(AIDR 3D IR).The following parameters were recorded:subjective image quality score,contrast dose and CT dose volume index(CTDI vol),dose length product(DLP),effective dose(ED)and iodine content.In axial view,mean CT values of pulmonary arteries were measured.Results There were no significant differences in background noise,signal noise ratio(SNR),carrier-to-noise ratio(CNR),subjective evaluation and mean CT values of pulmonary arteries between two groups(P>0.05).Contrast medium,injection rate,iodine content,CTDI vol.,DLP and ED in group B were declined from group A by 45.25%,12.09%,52.66%,49.12%,49.25%and 49.01%by reducing tube voltage from 100kVp to 80kVp.All differences were statistically significant(P<0.05).Conclusion CTPA protocol by reducing tube voltage as well as contrast agent during a single inspiratory breath-hold is feasible and radiation dose exposure can be easily reduced.

关 键 词：肺动脉CT血管成像 X线计算机体层摄影(CT) 辐射剂量 肺动脉栓塞 对比剂 

分 类 号：R814.4[医药卫生—影像医学与核医学] R543.2[医药卫生—放射医学]