Department of Radiology, Medical University Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
Eur Radiol. 2012 Feb;22(2):279-86. doi: 10.1007/s00330-011-2251-y. Epub 2011 Aug 28.
To compare image quality and radiation dose of high-pitch dual-source computed tomography (DSCT), dual energy CT (DECT) and conventional single-source spiral CT (SCT) for pulmonary CT angiography (CTA) on a 128-slice CT system.
Pulmonary CTA was performed with five protocols: high-pitch DSCT (100 kV), high-pitch DSCT (120 kV), DECT (100/140 kV), SCT (100 kV), and SCT (120 kV). For each protocol, 30 sex, age, and body-mass-index (mean 25.3 kg/m(2)) matched patients were identified. Retrospectively, two observers subjectively assessed image quality, measured CT attenuation (HU±SD) at seven central and peripheral levels, and calculated signal-to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR). Radiation exposure parameters (CTDIvol and DLP) were compared.
Subjective image quality was rated good to excellent in >92% (>138/150) with an interobserver agreement of 91.4%. The five protocols did not significantly differ in image quality, neither by subjective, nor by objective measures (SNR, CNR). By contrast, radiation exposure differed between protocols: significant lower radiation was achieved by using high-pitch DSCT at 100 kV (p < 0.01 in all). Radiation exposure of DECT was in between SCT at 100 kV and 120 kV.
SCT, high-pitch DSCT, and DECT protocols techniques result in similar subjective and objective image quality, but radiation exposure was significantly lower with high-pitch DSCT at 100 kV.
New CT protocols show promising results in pulmonary embolism assessment. High-pitch dual-source CT (DSCT) at 100 kV provides radiation dose savings for pulmonary CTA. High-pitch DSCT at 100 kV maintains diagnostic image quality for pulmonary CTA. Dual energy CT uses more radiation but also provides lung perfusion evaluation. Whether the additional perfusion data is worth the extra radiation remains undetermined.
比较在 128 层 CT 系统上使用高螺距双源 CT（DSCT）、双能 CT（DECT）和常规单源螺旋 CT（SCT）进行肺动脉 CT 血管造影（CTA）的图像质量和辐射剂量。
采用 5 种方案进行肺动脉 CTA：高螺距 DSCT（100 kV）、高螺距 DSCT（120 kV）、DECT（100/140 kV）、SCT（100 kV）和 SCT（120 kV）。对每个方案，各选取 30 名性别、年龄和体重指数（均值 25.3 kg/m²）匹配的患者。回顾性地，两位观察者对图像质量进行主观评估，测量七个中心和外周层面的 CT 衰减值（HU±SD），并计算信噪比（SNR）和对比噪声比（CNR）。比较辐射暴露参数（CTDIvol 和 DLP）。
主观图像质量评分在 >92%（>138/150），观察者间一致性为 91.4%。5 种方案的图像质量在主观和客观方面均无显著差异（SNR、CNR）。相比之下，方案之间的辐射暴露量存在差异：高螺距 DSCT 100 kV 可显著降低辐射（所有 p 值均 <0.01）。DECT 的辐射暴露量位于 SCT 100 kV 和 120 kV 之间。
SCT、高螺距 DSCT 和 DECT 方案均可获得相似的主观和客观图像质量，但高螺距 DSCT 100 kV 可显著降低辐射暴露量。
新的 CT 方案在肺栓塞评估中显示出良好的结果。高螺距双源 CT（DSCT）100 kV 可为肺动脉 CTA 提供辐射剂量节省。高螺距 DSCT 100 kV 保持肺动脉 CTA 的诊断图像质量。双能 CT 使用更多的辐射，但也提供肺灌注评估。额外的灌注数据是否值得额外的辐射仍不确定。
