Johnson Thorsten R C, Nikolaou Konstantin, Busch Stephanie, Leber Alexander W, Becker Alexander, Wintersperger Bernd J, Rist Carsten, Knez Andreas, Reiser Maximilian F, Becker Christoph R
Department Clinical Radiology, Medical Clinic I, University of Munich, Grosshadern Campus, Munich, Germany.
Invest Radiol. 2007 Oct;42(10):684-91. doi: 10.1097/RLI.0b013e31806907d0.
The aim of this study was to evaluate the diagnostic accuracy of dual-source computed tomography (DSCT) with reference to invasive coronary angiography in the diagnosis of coronary artery disease (CAD) on a per-patient as well as on a per-segment basis.
Thirty-five patients with known or suspected CAD underwent both DSCT (Somatom Definition, Siemens Medical Solutions) and quantitative x-ray coronary angiography (QCA). Parameters of CT acquisition were gantry rotation time 0.330 seconds (ie, temporal resolution 83 milliseconds), tube voltage 120 kV, tube current 560 mA with ECG-triggered tube current modulation and full current at 70% of the cardiac cycle for heart rates below 70 beats per minute or full current between 30% and 80% for higher and arrhythmic heart rates. The pitch was also adapted to the heart rate, ranging from 0.2 to 0.43. Volume and flow rate of contrast material (Ultravist 370, Schering AG) were adapted to the patient's body weight. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DSCT in the detection or exclusion of significant CAD (ie, stenoses >50%) were evaluated on a per-patient and per-segment basis.
All 35 CT angiograms were of diagnostic image quality. QCA demonstrated significant CAD in 48% (n = 17) and nonsignificant disease or normal coronary angiograms in 52% (n = 18) of the patients. Sensitivity, specificity, PPV, and NPV of DSCT on a per-patient basis were 100%, 89%, 89%, and 100%, respectively. On a per-segment basis, 473 of 481 coronary artery segments were assessable (98%). QCA demonstrated stenoses >50% in 32 segments (7%), and no disease or nonsignificant disease in 433 segments (93%). For the detection of stenoses >50% on a per-segment basis, DSCT showed a sensitivity, specificity, PPV, and NPV of 88%, 98%, 78%, and 99%, respectively.
The comparison of coronary DSCT with QCA shows a very robust image quality and a high diagnostic accuracy in a patient-based as well as a per-segment analysis. Maximal sensitivity and NPV in the per-patient analysis show the strength of the technique in ruling out significant CAD.
本研究旨在评估双源计算机断层扫描（DSCT）相对于有创冠状动脉造影术在诊断冠状动脉疾病（CAD）时以患者个体以及以节段为基础的诊断准确性。
35例已知或疑似CAD的患者同时接受了DSCT（西门子医疗解决方案公司的Somatom Definition）和定量X线冠状动脉造影（QCA）检查。CT采集参数为：机架旋转时间0.330秒（即时间分辨率83毫秒），管电压120 kV，管电流560 mA，采用心电图触发的管电流调制，心率低于70次/分钟时在心动周期的70%时使用全电流，心率较高或心律不齐时在30%至80%之间使用全电流。螺距也根据心率进行调整，范围为0.2至0.43。造影剂（先灵公司的优维显370）的用量和流速根据患者体重进行调整。在患者个体以及节段基础上评估DSCT检测或排除显著CAD（即狭窄>50%）的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）。
所有35例CT血管造影图像均具有诊断质量。QCA显示48%（n = 17）的患者存在显著CAD，52%（n = 18）的患者无显著疾病或冠状动脉造影正常。DSCT在患者个体基础上的敏感性、特异性、PPV和NPV分别为100%、89%、89%和100%。在节段基础上，481个冠状动脉节段中有473个可评估（98%）。QCA显示32个节段（7%）存在>50%的狭窄，433个节段（93%）无疾病或无显著疾病。对于节段基础上>50%狭窄的检测，DSCT的敏感性、特异性、PPV和NPV分别为88%、98%、78%和99%。
冠状动脉DSCT与QCA的比较显示，在基于患者个体以及节段分析中，其图像质量非常可靠且诊断准确性高。患者个体分析中的最大敏感性和NPV显示了该技术在排除显著CAD方面的优势。
