Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Hoppe-Seyler-Strasse 3, 72076, Tuebingen, Germany.
Department of Radiology, Duke University Medical Center, Box 3808 Erwin Rd, Durham, NC, 27710, USA.
Eur Radiol. 2018 May;28(5):1818-1825. doi: 10.1007/s00330-017-5168-2. Epub 2017 Dec 1.
To compare a low-dose, tin-filtered, nonenhanced, high-pitch Sn100 kVp CT protocol (Sn100) with a standard protocol (STP) for the detection of calcifications in the ascending aorta in patients scheduled for cardiac surgery.
Institutional Review Board approval for this retrospective study was waived and the study was HIPAA-compliant. The study included 192 patients (128 men; age 68.8 ± 9.9 years), of whom 87 received the STP and 105 the Sn100 protocol. Size-specific dose estimates (SSDE) and radiation doses were obtained using dose monitoring software. Two blinded readers evaluated image quality on a scale from 1 (low) to 5 (high) and the extent of calcifications of the ascending aorta on a scale from 0 (none) to 10 (high), subdivided into 12 anatomic segments.
The Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy and 0.20 ± 0.04 mSv compared with the mean SSDE of 5.4 ± 2.2 mGy achieved with the STP protocol (p < 0.0001). Calcification burden was associated with age (p < 0.0001), but was independent of protocol with mean calcification scores of 0.48 ± 1.23 (STP) and 0.55 ± 1.25 (Sn100, p = 0.18). Reader agreement was very good (STP κ = 0.87 ± 0.02, Sn100 κ = 0.88 ± 0.01). The STP protocol provided a higher subjective image quality than the Sn100 protocol: STP median 4, interquartile range 4-5, vs. SN100 3, 3-4; p < 0.0001) and a slightly better depiction of calcification (STP 5, 4-5, vs. Sn100 4, 4-5; p < 0.0001).
The optimized Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy while the depiction of calcifications remained good, and there was no systematic difference in calcification burden between the two protocols.
• Tin-filtered, low-dose CT can be used to assess aortic calcifications before cardiac surgery • An optimized Sn100 protocol achieved a mean SSDE of only 0.5 ± 0.1 mGy • The depiction of atherosclerosis of the thoracic aorta was similar with both protocols • The depiction of relevant thoracic pathologies before cardiac surgery was similar with both protocols.
比较低剂量、锡滤过、非增强、高螺距 Sn100 kVp CT 方案（Sn100）与标准方案（STP）在检测拟行心脏手术患者升主动脉钙化中的应用。
本回顾性研究获得机构审查委员会批准豁免，且符合 HIPAA 规定。该研究纳入 192 例患者（128 例男性；年龄 68.8±9.9 岁），其中 87 例行 STP，105 例行 Sn100 方案。使用剂量监测软件获得特定大小剂量估计值（SSDE）和辐射剂量。两名盲法读者分别对图像质量（1 分表示低，5 分表示高）和升主动脉钙化程度（0 分表示无，10 分表示严重）进行评估，后者按 12 个解剖节段进行细分。
Sn100 方案的平均 SSDE 仅为 0.5±0.1mGy 和 0.20±0.04mSv，而 STP 方案的平均 SSDE 为 5.4±2.2mGy（p＜0.0001）。钙化负担与年龄相关（p＜0.0001），但与方案无关，钙化评分分别为 0.48±1.23（STP）和 0.55±1.25（Sn100，p=0.18）。读者间的一致性非常好（STPκ=0.87±0.02，Sn100κ=0.88±0.01）。STP 方案提供的主观图像质量优于 Sn100 方案：STP 中位数 4 分，四分位距 4-5 分，而 Sn100 中位数 3 分，四分位距 3-4 分；p＜0.0001），且钙化的显示略好（STP 5 分，4-5 分，Sn100 4 分，4-5 分；p＜0.0001）。
优化的 Sn100 方案的平均 SSDE 仅为 0.5±0.1mGy，同时钙化的显示仍然良好，两种方案之间的钙化负担没有系统差异。
• 锡滤过、低剂量 CT 可用于评估心脏手术前的主动脉钙化• 优化的 Sn100 方案的平均 SSDE 仅为 0.5±0.1mGy• 两种方案对胸主动脉粥样硬化的显示相似• 两种方案对心脏手术前相关胸部病变的显示相似。
