Department of Radiology and Radiological Science and Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA.
Eur Radiol. 2013 Jan;23(1):125-32. doi: 10.1007/s00330-012-2580-5. Epub 2012 Jul 10.
Comparison of coronary artery stent assessment with cardiac CT angiography (cCTA) using traditional filtered back projection (FBP) and sinogram affirmed iterative reconstruction (SAFIRE), in both full- and half-radiation dose image data.
Dual-source cCTA studies of 37 implanted stents were reconstructed at full- and half-radiation dose with FBP and SAFIRE. Half-dose data were based on projections from one DSCT detector. In-stent noise, signal-to-noise ratio (SNR), and stent-lumen attenuation increase ratio (SAIR) were measured and image quality graded. Stent volumes were measured to gauge severity of beam hardening artefacts.
Full-dose SAFIRE reconstructions were superior to full-dose FBP vis-à-vis in-stent noise (21.2 ± 6.6 vs. 35.7 ± 17.5; P < 0.05), SNR (22.1 ± 8.6 vs. 14.3 ± 6.7; P < 0.05), SAIR (19.6 ± 17.6 vs. 33.4 ± 20.4%; P < 0.05), and image quality (4.2 ± 0.86 vs. 3.5 ± 1.0; P < 0.05). Stent volumes were lower measured with SAFIRE (119.9 ± 53.7 vs. 129.8 ± 65.0 mm(3); P > 0.05). Comparing half-dose SAFIRE with full-dose FBP, in-stent noise (26.7 ± 13.0 vs. 35.7 ± 17.5; P < 0.05) and SNR (18.2 ± 6.9 vs. 14.3 ± 6.7; P < 0.05) improved significantly. SAIR (31.6 ± 24.3 vs. 33.4 ± 20.4%; P > 0.05), stent volume (129.6 ± 57.3 vs. 129.8 ± 65.0 mm(3); P > 0.05), and image quality (3.5 ± 1.0 vs. 3.7 ± 1.1; P > 0.05) did not differ. Radiation dose decreased from 8.7 ± 5.2 to 4.3 ± 2.6 mSv.
Iterative reconstruction significantly improves imaging of coronary artery stents by CT compared with FBP, even with half-radiation-dose data.
比较冠状动脉支架评估与心脏 CT 血管造影（cCTA），使用传统的滤波反投影（FBP）和正弦图确认迭代重建（SAFIRE），在全剂量和半剂量图像数据中。
使用双源 cCTA 对 37 个植入支架进行全剂量和半剂量重建，使用 FBP 和 SAFIRE。半剂量数据基于来自一个 DSCT 探测器的投影。测量支架内噪声、信噪比（SNR）和支架腔衰减增加比（SAIR），并对图像质量进行分级。测量支架体积以评估束硬化伪影的严重程度。
全剂量 SAFIRE 重建优于全剂量 FBP 支架内噪声（21.2±6.6 vs. 35.7±17.5；P<0.05）、SNR（22.1±8.6 vs. 14.3±6.7；P<0.05）、SAIR（19.6±17.6 vs. 33.4±20.4%；P<0.05）和图像质量（4.2±0.86 vs. 3.5±1.0；P<0.05）。使用 SAFIRE 测量的支架体积较低（119.9±53.7 vs. 129.8±65.0 mm(3)；P>0.05）。与全剂量 FBP 相比，半剂量 SAFIRE 重建的支架内噪声（26.7±13.0 vs. 35.7±17.5；P<0.05）和 SNR（18.2±6.9 vs. 14.3±6.7；P<0.05）显著提高。SAIR（31.6±24.3 vs. 33.4±20.4%；P>0.05）、支架体积（129.6±57.3 vs. 129.8±65.0 mm(3)；P>0.05）和图像质量（3.5±1.0 vs. 3.7±1.1；P>0.05）没有差异。辐射剂量从 8.7±5.2 降至 4.3±2.6 mSv。
与 FBP 相比，迭代重建通过 CT 显著改善了冠状动脉支架的成像，即使使用半剂量数据也是如此。
