TU‐A‐201B‐03: Dose Reduction and Image Quality Benefits Using Model Based Iterative Reconstruction (MBIR) Technique for Computed Tomography
TU‐A‐201B‐03: Dose Reduction and Image Quality Benefits Using Model Based Iterative Reconstruction (MBIR) Technique for Computed Tomography
复制标题
TU-A-201B-03：使用基于模型的迭代重建 (MBIR) 技术进行计算机断层扫描可减少剂量并提高图像质量
DOI：
--
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
J. Hsieh
中科院分区：
文献类型：
--
作者：
G. Yadava;S. Kulkarni;Z. R. Colon;Jean;J. Hsieh
目的：旨在证明结合计算机断层扫描（CT）系统物理模型的基于模型的迭代重建（MBIR）技术的图像质量受益和显著降低剂量的潜力。方法和材料：基于模型的迭代重建（MBIR），最大后验概率（MAP）估计与边缘保持先验，已被开发用于X射线CT图像重建。它利用更准确的成像链物理模型，考虑到系统光学、噪声和数据中的非理想性，因此与传统的滤波反投影（FBP）相比，在显著降低的剂量水平下提高了图像质量。在这项工作中，使用GE多层CT系统采集一组多剂量数据和标准FBP重建。对于分辨率评估，在三个剂量水平（40、20和10 mGy，120 kVp光谱）下扫描Catphan 600 ®体模，并使用两种方法重建图像：ASiR的FBP和MBIR。对于伪影和图像质量评价，使用拟人CT腹部体模（京都Kagaku Co.，Ltd）在四个剂量水平（120 kVp光谱，225、112、54和27 mAs）下进行扫描，并在切片和多平面重建（MPR）模式下对标准FBP和MBIR进行了图像质量比较研究。此外，也很少有临床病例研究用于比较实际临床数据中的成像性能。结果如下：从分辨率研究中，我们发现，即使在1/4剂量下，与采用ASiR的标准最先进的FBP相比，MBIR图像的分辨率也有所提高，噪声显著降低。使用ASIR可在等效FBP图像质量的情况下减少高达50%的剂量。对于拟人体模，即使低于1/8剂量，MBIR图像在切片和MPR模式下的表现也优于相应的FBP图像，证明了临床CT中剂量降低的巨大潜力，但提高了图像质量。结论：MBIR方法的结果证明了临床CT中剂量降低和图像质量改善的巨大潜力。
Purpose: To demonstrate the image‐quality benefits and potential for significant dose reduction with Model‐Based Iterative Reconstruction (MBIR) technique incorporating physical model of computed tomography(CT) systems. Method and Materials: A model based iterative reconstruction (MBIR), a maximum a posteriori (MAP) estimate with edge‐preserving prior, has been developed for x‐ray CTimage reconstruction. It utilizes a more accurate physical model of the imaging chain accounting for system‐optics, noise and non‐idealities in the data, hence improves image quality compared to conventional filtered backprojection (FBP) at significantly reduced dose levels. In this work, a GE multi‐slice CT system was used to acquire a set of multi‐dose data and standard FBP reconstruction. For resolution assessment, a Catphan600® phantom was scanned at three dose levels (40, 20, and 10 mGy with 120kVp spectrum), and images were reconstructed using two methods: FBP with ASiR, and the MBIR. For artifact and image‐quality evaluations, an anthropomorphic CT abdomen phantom (Kyoto Kagaku Co., Ltd) was scanned at four dose levels (120kVp spectrum with 225, 112, 54, and 27 mAs), and a comparative image‐quality study between standard FBP and MBIR in slice and multi‐planar reformat (MPR) modes was made. In addition, few clinical case studies were also used to compare the imaging performance in actual clinical data. Results: From the resolution study, we found that even at 1/4th dose, MBIR images have improved resolution at significantly reduced noise compared to standard state‐of‐the‐art FBP with ASiR. Use of ASIR provides up to 50% dose reduction with equivalent FBP image‐quality. For anthropomorphic phantom, even below 1/8th dose, MBIR images outperformed the corresponding FBP images in both, slice and MPR modes, demonstrating immense potential for dose reduction, yet improved image quality, in clinical CT.Conclusion: Results of the MBIR method demonstrated significant potential for dose reduction and image‐quality improvements in clinical CT.