Four-dimensional computed tomography of the left ventricle, Part I: Motion artifact reduction.
Four-dimensional computed tomography of the left ventricle, Part I: Motion artifact reduction.
复制标题
左心室四维计算机断层扫描，第一部分：运动伪影减少。
DOI：
10.1002/mp.15709
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发表时间：
2022
期刊：
影响因子：
3.8
通讯作者：
McVeigh,ElliotR
中科院分区：
文献类型：
--
作者：
Pack,JedD;Manohar,Ashish;Ramani,Sathish;Claus,Bernhard;Yin,Zhye;Contijoch,FranciscoJ;Schluchter,AndrewJ;McVeigh,ElliotR
目的标准四维计算机断层扫描（4DCT）心脏重建通常包括螺旋伪影，其不仅取决于心脏的运动，还取决于采集数据的机架角度范围。我们寻求减少这些运动伪影，从而提高左心室壁的位置在4DCT图像series.MethodsWe使用的运动伪影减少方法（ResyncCT），主要是基于共轭对部分角度重建（PAR）图像的准确性。在识别出未校正图像中存在运动伪影的关键位置后，使用修改的互相关函数分析PAR图像中的成对子体积，以估计这些位置处的3D速度和加速度矢量。随后的运动补偿过程（也基于PAR图像）包括创建密集运动场，然后进行反向投影和扭曲式补偿。该算法在3D打印体模上进行了测试，该体模代表左心室（LV）和严重伪影损坏的具有挑战性的临床病例。ResultsThe结果从我们的初步体模测试以及临床心脏扫描显示清晰的内膜边缘和解决双壁伪影。当被视为时间序列时，与未校正的图像相比，校正后的图像表现出更平滑的LV内膜边界运动。此外，从我们的体模研究的定量结果表明，ResyncCT处理减少endoembryonic表面距离误差从0.9 ± 0.8到0.2 ± 0.1 mm.ConclusionsThe ResyncCT算法被证明是有效的减少运动伪影和恢复准确的壁位置。还给出了关于共轭PAR图像的使用和更普遍的CT运动伪影减少技术的一些观点。
PurposeStandard four‐dimensional computed tomography (4DCT) cardiac reconstructions typically include spiraling artifacts that depend not only on the motion of the heart but also on the gantry angle range over which the data was acquired. We seek to reduce these motion artifacts and, thereby, improve the accuracy of left ventricular wall positions in 4DCT image series.MethodsWe use a motion artifact reduction approach (ResyncCT) that is based largely on conjugate pairs of partial angle reconstruction (PAR) images. After identifying the key locations where motion artifacts exist in the uncorrected images, paired subvolumes within the PAR images are analyzed with a modified cross‐correlation function in order to estimate 3D velocity and acceleration vectors at these locations. A subsequent motion compensation process (also based on PAR images) includes the creation of a dense motion field, followed by a backproject‐and‐warp style compensation. The algorithm was tested on a 3D printed phantom, which represents the left ventricle (LV) and on challenging clinical cases corrupted by severe artifacts.ResultsThe results from our preliminary phantom test as well as from clinical cardiac scans show crisp endocardial edges and resolved double‐wall artifacts. When viewed as a temporal series, the corrected images exhibit a much smoother motion of the LV endocardial boundary as compared to the uncorrected images. In addition, quantitative results from our phantom studies show that ResyncCT processing reduces endocardial surface distance errors from 0.9 ± 0.8 to 0.2 ± 0.1 mm.ConclusionsThe ResyncCT algorithm was shown to be effective in reducing motion artifacts and restoring accurate wall positions. Some perspectives on the use of conjugate‐PAR images and on techniques for CT motion artifact reduction more generally are also given.