大螺距三联个体化对比剂方案在胸痛患者检查中的价值分析  

Preliminary study of individualized contrast injection protocols in triple-rule-out computed tomography angiography using a high-pitch dual-source technique

作　　者：李金燕[1] 张国伟 王锡明 段艳华 纪晓鹏[1] 曹婷 孙文悦 齐耀东 

机构地区：[1] 山东省立医院西院放射科,济南,250000 [2] 烟台山医院放射科 [3] 山东省心脑血管疾病诊治重点实验室 [4] 泰山市中心医院放射科 [5] 枣庄市煤矿医院放射科

出　　处：《中华医学杂志》2015年第29期2363-2367,共5页National Medical Journal of China

摘　　要：目的 探讨个体化对比剂注射方案在低心率胸痛患者Flash一站式扫描中应用的可行性.方法 自2014年4至8月,收集山东省医学影像学研究所因朐痛行三联检查的患者共63例,分为两组,其中试验组31例,心率稳定且在65次/min以下,采用基于体重的3期对比剂注射方案（350mgI/ml,A：0.7 ml/kg,固定注射对比剂时间10s,B：同速率注射1∶1混药8 s,C：同速率注射生理盐水6～7 s）,另外32例胸痛患者作为对照组,无心率要求,采用传统回顾性心电门控扫描,双相对比剂注射方案（对比剂90 ml,生理盐水40 ml,速度5 ml/s）,分别测量并比较两组间主动脉（升主动脉、主动脉弓、胸降主动脉中段、远段）,肺动脉（肺动脉干、左、右肺动脉）,左冠状动脉主干、右冠状动脉近段的CT值,计算主动脉、肺动脉的平均强化值及信噪比、对比度噪声比.由两名放射科医师采用双盲法对图像质量进行主观评价,采用5分法（1分优,5分不能诊断）.计算有效辐射剂量（转换系数k取0.017 m·mGy-1·cm-1）.结果 所得主动脉、冠状动脉CT值、噪声、信噪比、对比度噪声比及主观图像质量评分试验组与对照组间差异无统计学意义,肺动脉CT值差异有统计学意义（试验组CT值低于对照组）,但仍满足诊断标准,而两组间平均对比剂用量、平均有效辐射剂量,试验组明显低与对照组[（72±10）比（90 ±0）ml,P＜0.01;（3.0±0.3）比（18.8 ±2.7）mSv,P＜0.01].结论 对于低心率患者,采用Flash胸痛三联序列扫描及个体化对比剂注射方案,扫描速度快,辐射剂量及对比剂用量较传统回顾性心电门控扫描均降低,且能够获得满足诊断的主动脉、冠状动脉及肺动脉强化CT值及图像质量.Objective To assess the feasibility of individual contrast injection protocols in triplerule-out computed tomography examination using a dual-source Flash-chest-pain technique.Methods From April to August 2014,63 patients with undifferentiated acute chest pain underwent ECG-synchronized dualspiral chest CT angiography.31 Patients,who all had low （〈 65 bpm） and stable heart rate underwent TRO CT angiography in a Flash mode,with an individual triphasic contrast protocol based on weight （350 mgI/ml,A：0.7 ml/kg,setting 10 s duration time;B：8 s mixture of the contrast agent and saline at the same rate;C：6-7 s saline at the same rate）.In contrast,the other patients,who had random heart rate,underwent TRO CT angiography in a traditional retrospectively mode with an identical biphasic contrast protocol（350 mgI/ml,A：contrast agent 90 ml,B：saline 40 ml,injection rate 5 mL/s）.Quantitative image analysis assessed vessel attenuation of aorta,coronary and pulmonary artery,signal-to-noise ratio （SNR） and contrast-to noise ratio （CNR）.Subjective image was assessed on a 5 point scale （1：excellent,5：nondiagnosis） by two blind observers.The effective dose was calculated from the dose length product （DLP） using a conversion coefficient of 0.017 mSv ·mGy-1 · cm-1 Results There was no significant difference of aorta and coronary artery attenuation,noise,SNR,CNR or subjective image quality between both patient groups.Pulmonary artery attenuation was lower in test group than in control group,but it also can meet the diagnostic criteria.Moreover,the mean contrast agent and the effective dose were lower in test group than in control group （72 ±10）vs （90±0） ml,P〈0.01 and （3.0 ±0.3） vs （18.8 ±2.7） mSv,P〈0.01.Conclusion As to patients with low and stable heart rate,this individual contrast protocol along with dualsource high-pith technique,is capable of achieving satisfactory image which could meet the diagnostic requirements with lower contrast agent and lower effective d

关 键 词：体层摄影术 X线 血管造影术 对比剂 胸痛 

分 类 号：R816.2[医药卫生—放射医学]