Zhen Xin, Zhou Ling-hong, Lu Wen-ting, Zhang Shu-xu, Zhou Lu
Southern Medical University, Guangzhou, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2010 Dec;30(12):2619-24.
To validate the efficiency and accuracy of an improved Demons deformable registration algorithm and evaluate its application in contour recontouring in 4D-CT.
To increase the additional Demons force and reallocate the bilateral forces to accelerate convergent speed, we propose a novel energy function as the similarity measure, and utilize a BFGS method for optimization to avoid specifying the numbers of iteration. Mathematical transformed deformable CT images and home-made deformable phantom were used to validate the accuracy of the improved algorithm, and its effectiveness for contour recontouring was tested.
The improved algorithm showed a relatively high registration accuracy and speed when compared with the classic Demons algorithm and optical flow based method. Visual inspection of the positions and shapes of the deformed contours agreed well with the physician-drawn contours.
Deformable registration is a key technique in 4D-CT, and this improved Demons algorithm for contour recontouring can significantly reduce the workload of the physicians. The registration accuracy of this method proves to be sufficient for clinical needs.
验证一种改进的Demons可变形配准算法的效率和准确性，并评估其在4D-CT轮廓重新勾画中的应用。
为增加额外的Demons力并重新分配双边力以加快收敛速度，我们提出一种新颖的能量函数作为相似性度量，并利用BFGS方法进行优化以避免指定迭代次数。使用数学变换后的可变形CT图像和自制的可变形体模来验证改进算法的准确性，并测试其在轮廓重新勾画方面的有效性。
与经典的Demons算法和基于光流的方法相比，改进后的算法显示出相对较高的配准精度和速度。对变形轮廓的位置和形状进行目视检查，结果与医生绘制的轮廓吻合良好。
可变形配准是4D-CT中的一项关键技术，这种用于轮廓重新勾画的改进Demons算法可显著减轻医生的工作量。该方法的配准精度证明足以满足临床需求。
