UCLA Department of Radiation Oncology, Los Angeles, CA 90095, USA.
Phys Med Biol. 2013 Jun 7;58(11):L31-6. doi: 10.1088/0031-9155/58/11/L31. Epub 2013 May 2.
To report on a novel technique for providing artifact-free quantitative four-dimensional computed tomography (4DCT) image datasets for breathing motion modeling. Commercial clinical 4DCT methods have difficulty managing irregular breathing. The resulting images contain motion-induced artifacts that can distort structures and inaccurately characterize breathing motion. We have developed a novel scanning and analysis method for motion-correlated CT that utilizes standard repeated fast helical acquisitions, a simultaneous breathing surrogate measurement, deformable image registration, and a published breathing motion model. The motion model differs from the CT-measured motion by an average of 0.65 mm, indicating the precision of the motion model. The integral of the divergence of one of the motion model parameters is predicted to be a constant 1.11 and is found in this case to be 1.09, indicating the accuracy of the motion model. The proposed technique shows promise for providing motion-artifact free images at user-selected breathing phases, accurate Hounsfield units, and noise characteristics similar to non-4D CT techniques, at a patient dose similar to or less than current 4DCT techniques.
为了报告一种提供无伪影的定量四维计算机断层扫描（4DCT）图像数据集用于呼吸运动建模的新技术。商业临床 4DCT 方法难以处理不规则呼吸。由此产生的图像包含运动引起的伪影，这些伪影可能会扭曲结构并不准确地描述呼吸运动。我们开发了一种用于运动相关 CT 的新型扫描和分析方法，该方法利用标准的重复快速螺旋采集、同时进行的呼吸替代测量、可变形图像配准以及已发布的呼吸运动模型。运动模型与 CT 测量的运动之间的平均差异为 0.65mm，这表明了运动模型的精度。预测一个运动模型参数的散度积分是一个常数 1.11，在这种情况下，它被发现为 1.09，这表明了运动模型的准确性。所提出的技术有望在用户选择的呼吸阶段提供无运动伪影的图像、准确的亨氏单位以及与非 4DCT 技术相似的噪声特性，而患者剂量与当前 4DCT 技术相似或更小。
