Mukherjee Joyeeta Mitra, McNamara Joseph E, Johnson Karen L, Dey Joyoni, King Michael A
The authors are with the Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655 USA.
IEEE Trans Nucl Sci. 2009 Feb;56(1):147-155. doi: 10.1109/TNS.2008.2010319.
Motion of patients undergoing cardiac SPECT perfusion imaging causes artifacts in the acquired images which may lead to difficulty in interpretation. Our work investigates a technique of obtaining patient motion estimates from retro-reflective markers on stretchy bands wrapped around the chest and abdomen of patients being imaged clinically. Motion signals obtained from the markers consist of at least two components, body motion (BM) and periodic motion (PM) due to respiration. We present a method for separating these components from the motion-tracking data of each marker, and then report a method for combining the BM estimated from chest markers to estimate the 6-degree-of-freedom (6-DOF) rigid-body motion (RBM) of the heart. Motion studies of volunteers and patients are used to evaluate the methods. Illustrative examples of the motion of the heart due to patient body movement and respiration (upward creep) are presented and compared to estimates of the motion of the heart obtained directly from SPECT data. Our motion-tracking method is seen to give reasonable agreement with the motion-estimates from the SPECT data while being considerably less noisy.
接受心脏单光子发射计算机断层扫描（SPECT）灌注成像的患者的运动，会在采集的图像中产生伪影，这可能导致解读困难。我们的工作研究了一种从临床成像患者胸部和腹部缠绕的弹性带上的反光标记获取患者运动估计的技术。从标记获得的运动信号至少由两个分量组成，即身体运动（BM）和由于呼吸引起的周期性运动（PM）。我们提出了一种从每个标记的运动跟踪数据中分离这些分量的方法，然后报告一种将从胸部标记估计的BM相结合以估计心脏的六自由度（6-DOF）刚体运动（RBM）的方法。使用志愿者和患者的运动研究来评估这些方法。给出了由于患者身体运动和呼吸（向上蠕动）导致的心脏运动的示例，并与直接从SPECT数据获得的心脏运动估计进行比较。我们的运动跟踪方法与来自SPECT数据的运动估计有合理的一致性，同时噪声要小得多。
