基于配准的肺4D-CT图像超分辨率重建

肺4D-CT数据在肺癌治疗中有重要意义.但肺4D-CT数据纵向(Z方向)分辨率低,为显示正确比例图像需进行插值运算,由此带来图像的模糊.本文提出了一种基于Active Demons配准的超分辨率重建技术来提高肺4D-CT图像分辨率.我们将不同相位同一位置的低分辨率图像视为不同"帧"图像.首先采用Active Demons配准方法得到不同"帧"图像之间的运动估计;而后采用凸集投影(Projection Onto Convex Set,POCS)超分辨率算法重建高分辨率肺图像.实验结果表明,与三次样条插值和反投影方法相比较,我们的方法能得到更清晰的肺图像,明显增强图像结构.

Registration Based Super-Resolution Reconstruction for Lung 4D-CT Image

Lung 4D-CT plays an important role in lung cancer radiotherapy.However,due to the great inter-slice thickness,the fuzzy images will be induced because of interpolation operation during the multi-plane display.In this paper,we take the low-resolution images of different phases in the corresponding position as different "frame" images,and propose a registration based super-resolution reconstruction method to improve the resolution of lung 4D-CT images.First,we employ the Active Demons registration to estimate the motion field between different "frames".Then,the projection onto convex set (POCS) approach is employed to reconstruction high-resolution lung images.The experimental results show that our method can get more clear lung images and significantly enhance image structure,compared with the cubic spline interpolation and back projection method.