Thomas Christoph K, Mühlenbruch Georg, Wildberger Joachim E, Hohl Christian, Das Marco, Günther Rolf W, Mahnken Andreas H
Department of Diagnostic Radiology, University Hospital, RWTH-Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
Invest Radiol. 2006 Sep;41(9):668-73. doi: 10.1097/01.rli.0000233324.09603.dd.
We sought to compare an 80-kVp coronary calcium scoring protocol with the standard protocol of 120 kVp in terms of accuracy and reproducibility and to assess its dose reduction potential.
An anthropomorphic heart phantom with calcium cylinders was scanned with different tube currents at 80 kVp and 120 kVp using a 16-slice multislice CT (MSCT) scanner. An adapted threshold for 80 kVp was calculated. Accuracy and reproducibility for calcium mass, volume, and Agatston score were analyzed using F-tests. The radiation doses needed to produce artifact-free images were determined.
Accuracy (measurement errors: mass 120 kVp +4.6%, mass 80 kVp -6.9%, volume 120 kVp +78.8%, volume 80 kVp +58.2%) and reproducibility (F-tests: mass: P = 0.4998, volume: P = 0.9168, Agatston: P = 0.5422) were comparable at both tube voltages. Avoiding the appearance of artificial lesions, a CTDI(w,eff) of 10.7 mGy was needed at 120 kVp versus 4.6 mGy at 80 kVp (dose reduction of 57%).
Using an 80-kVp protocol in coronary calcium scoring, a relevant dose reduction is possible without compromising reproducibility and accuracy.
我们试图比较80千伏峰值（kVp）的冠状动脉钙化评分方案与120 kVp的标准方案在准确性和可重复性方面的差异，并评估其降低辐射剂量的潜力。
使用16层多层螺旋CT（MSCT）扫描仪，对带有钙圆柱体的仿真心脏模型在80 kVp和120 kVp下采用不同管电流进行扫描。计算出80 kVp的适配阈值。使用F检验分析钙质量、体积和阿加斯顿评分的准确性和可重复性。确定生成无伪影图像所需的辐射剂量。
在两种管电压下，准确性（测量误差：质量120 kVp时为+4.6%，质量80 kVp时为-6.9%，体积120 kVp时为+78.8%，体积80 kVp时为+58.2%）和可重复性（F检验：质量：P = 0.4998，体积：P = 0.9168，阿加斯顿：P = 0.5422）具有可比性。为避免出现人工伪影，120 kVp时需要的加权CT剂量指数（CTDI(w,eff)）为10.7毫戈瑞（mGy），而80 kVp时为4.6 mGy（剂量降低57%）。
在冠状动脉钙化评分中使用80 kVp方案，可以在不影响可重复性和准确性的情况下大幅降低辐射剂量。
