Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elasti...Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elastic mesh. However, the reconstructed shape is not smooth because the limited control points are only distributed on the edge of the elastic mesh.Alternatively, statistical-model-based methods, which include shape-model-based and intensity-model-based methods, are introduced due to their smooth reconstruction. However, both suffer from limitations. With the shape-model-based method, only the boundary profile is considered, leading to the loss of valid intensity information. For the intensity-based-method, the computation speed is slow because it needs to calculate the intensity distribution in each iteration. To address these issues, we propose a new reconstruction method using X-ray images and a specimen’s CT data. Specifically, the CT data provides both the shape mesh and the intensity model of the vertebra. Intensity model is used to generate the deformation field from X-ray images, while the shape model is used to generate the patient specific model by applying the calculated deformation field.Experiments on the public synthetic dataset and clinical dataset show that the average reconstruction errors are 1.1 mm and1.2 mm, separately. The average reconstruction time is 3 minutes.展开更多
荧光分子断层成像技术(fluorescence molecular tomography,FMT)系统中为获得体内光源的结构信息,需要利用CT体数据。FMT系统在进行光学图像与CT图像的配准时,由于两种模态图像的成像原理、图像风格和图像维度等方面的差异,导致传统配...荧光分子断层成像技术(fluorescence molecular tomography,FMT)系统中为获得体内光源的结构信息,需要利用CT体数据。FMT系统在进行光学图像与CT图像的配准时,由于两种模态图像的成像原理、图像风格和图像维度等方面的差异,导致传统配准方法耗时长、效果差。本研究提出了一种基于T2DR-Net(texture transfer and dense registration net)与互信息的光学-CT图像配准方法,实现FMT系统中白光图像与CT图像的配准。该方法将光学-CT图像配准分为粗配准和精配准两个部分。在粗配准阶段,利用CycleGAN实现了FMT白光图像和CT投影像的纹理迁移,以降低两种图像纹理差异对图像配准的影响,并提出了DenseReg-Net模型获取白光图像和CT投影像粗配准参数;在精配准阶段,通过互信息方法进一步对两种模态图像配准,并得到最终的配准结果。利用1330张光学图像和39711张CT投影像作为样本集来验证配准方法的有效性,实验结果表明,本研究提出的光学-CT图像配准方法,相关系数为0.8797±0.0175,结构相似性为0.8683±0.0051,模型配准时间为(2.88±1.39)s。模型的配准效果及其稳定性优于传统方法。此外,与传统方法相比,速度提升了约60倍。展开更多
基金supported in part by The National Key Research and Development Program of China(2018YFC2001302)the National Natural Science Foundation of China(61976209)+1 种基金CAS International Collaboration Key Project(173211KYSB20190024)Strategic Priority Research Program of CAS(XDB32040000)。
文摘Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elastic mesh. However, the reconstructed shape is not smooth because the limited control points are only distributed on the edge of the elastic mesh.Alternatively, statistical-model-based methods, which include shape-model-based and intensity-model-based methods, are introduced due to their smooth reconstruction. However, both suffer from limitations. With the shape-model-based method, only the boundary profile is considered, leading to the loss of valid intensity information. For the intensity-based-method, the computation speed is slow because it needs to calculate the intensity distribution in each iteration. To address these issues, we propose a new reconstruction method using X-ray images and a specimen’s CT data. Specifically, the CT data provides both the shape mesh and the intensity model of the vertebra. Intensity model is used to generate the deformation field from X-ray images, while the shape model is used to generate the patient specific model by applying the calculated deformation field.Experiments on the public synthetic dataset and clinical dataset show that the average reconstruction errors are 1.1 mm and1.2 mm, separately. The average reconstruction time is 3 minutes.
文摘荧光分子断层成像技术(fluorescence molecular tomography,FMT)系统中为获得体内光源的结构信息,需要利用CT体数据。FMT系统在进行光学图像与CT图像的配准时,由于两种模态图像的成像原理、图像风格和图像维度等方面的差异,导致传统配准方法耗时长、效果差。本研究提出了一种基于T2DR-Net(texture transfer and dense registration net)与互信息的光学-CT图像配准方法,实现FMT系统中白光图像与CT图像的配准。该方法将光学-CT图像配准分为粗配准和精配准两个部分。在粗配准阶段,利用CycleGAN实现了FMT白光图像和CT投影像的纹理迁移,以降低两种图像纹理差异对图像配准的影响,并提出了DenseReg-Net模型获取白光图像和CT投影像粗配准参数;在精配准阶段,通过互信息方法进一步对两种模态图像配准,并得到最终的配准结果。利用1330张光学图像和39711张CT投影像作为样本集来验证配准方法的有效性,实验结果表明,本研究提出的光学-CT图像配准方法,相关系数为0.8797±0.0175,结构相似性为0.8683±0.0051,模型配准时间为(2.88±1.39)s。模型的配准效果及其稳定性优于传统方法。此外,与传统方法相比,速度提升了约60倍。
