Respiratory motion correction in gated cardiac SPECT using quaternion-based, rigid-body registration.
Respiratory motion correction in gated cardiac SPECT using quaternion-based, rigid-body registration.
复制标题
使用基于四元数的刚体配准进行门控心脏 SPECT 中的呼吸运动校正。
DOI：
10.1118/1.3215531
复制
发表时间：
2009
期刊：
影响因子：
3.8
通讯作者：
Gilland,DavidR
中科院分区：
文献类型：
--
作者：
Parker,JasonG;Mair,BernardA;Gilland,DavidR
在本文中，介绍了一种新方法，使用具有由单位四元数参数化的旋转的刚体模型来估计门控心脏 SPECT 中呼吸引起的心脏运动。该方法基于通过使用优化的共轭梯度例程最小化由通常的光流约束产生的参考帧和变形帧之间的平方误差和。该方法不需要任何用户定义的参数或惩罚项，这简化了其在临床环境中的使用。使用数学模型，将该方法与主轴法以及用欧拉角表示旋转矩阵的迭代法进行定量比较。基于四元数的方法被证明在各种心肌外活动水平上比主轴方法更加准确和稳健。与欧拉角表示相比，基于四元数的方法具有相似的精度，但计算时间显着减少。最后，使用人类受试者的呼吸门控心脏 SPECT 采集来研究基于四元数的方法。与未校正的图像相比，运动校正的图像具有更高的清晰度和心肌均匀性。
In this article, a new method is introduced for estimating the motion of the heart due to respiration in gated cardiac SPECT using a rigid‐body model with rotation parametrized by a unit quaternion. The method is based on minimizing the sum of squared errors between the reference and the deformed frames resulting from the usual optical flow constraint by using an optimized conjugate gradient routine. This method does not require any user‐defined parameters or penalty terms, which simplifies its use in a clinical setting. Using a mathematical phantom, the method was quantitatively compared to the principal axis method, as well as an iterative method in which the rotation matrix was represented by Euler angles. The quaternion‐based method was shown to be substantially more accurate and robust across a wide range of extramyocardial activity levels than the principal axis method. Compared with the Euler angle representation, the quaternion‐based method resulted in similar accuracy but a significant reduction in computation times. Finally, the quaternion‐based method was investigated using a respiratory‐gated cardiac SPECT acquisition of a human subject. The motion‐corrected image has increased sharpness and myocardial uniformity compared to the uncorrected image.