Institute of Medical Informatics, University of Lübeck, Lübeck, Germany,
Int J Comput Assist Radiol Surg. 2014 May;9(3):367-77. doi: 10.1007/s11548-014-0976-1. Epub 2014 Jan 16.
Multimodality mammography using conventional 2D mammography and dynamic contrast-enhanced 3D magnetic resonance imaging (DCE-MRI) is frequently performed for breast cancer detection and diagnosis. Combination of both imaging modalities requires superimposition of corresponding structures in mammograms and MR images. This task is challenging due to large differences in (1) dimensionality and spatial resolution, (2) variations in tissue contrast, as well as (3) differences in breast orientation and deformation during the image acquisition. A new method for multimodality breast image registration was developed and tested.
Combined diagnosis of mammograms and MRI datasets was achieved by simulation of mammographic breast compression to overcome large differences in breast deformation. Surface information was extracted from the 3D MR image, and back-projection of the 2D breast contour in the mammogram was done. B-spline-based 3D/3D surface-based registration was then used to approximate mammographic breast compression. This breast deformation simulation was performed on 14 MRI datasets with 19 corresponding mammograms. The results were evaluated by comparison with distances between corresponding structures identified by an expert observer.
The evaluation revealed an average distance of 6.46 mm between corresponding structures, when an optimized initial alignment between both image datasets is performed. Without the optimization, the accuracy is 9.12 mm.
A new surface-based method that approximates the mammographic deformation due to breast compression without using a specific complex model needed for finite-element-based methods was developed and tested with favorable results. The simulated compression can serve as foundation for a point-to-line correspondence between 2D mammograms and 3D MR image data.
使用传统的二维(2D)乳房 X 光摄影和动态对比增强三维(3D)磁共振成像(DCE-MRI)进行多模态乳房成像,常用于乳腺癌的检测和诊断。两种成像方式的结合需要在乳房 X 光片和磁共振图像中叠加相应的结构。由于(1)维度和空间分辨率、(2)组织对比度的变化以及(3)在图像采集过程中乳房的方向和变形的差异,这项任务具有挑战性。本文开发并测试了一种新的多模态乳房图像配准方法。
通过模拟乳房 X 光摄影的乳房压缩来实现乳房 X 光摄影和 MRI 数据集的联合诊断,以克服乳房变形的巨大差异。从 3D MR 图像中提取表面信息,并在乳房 X 光片中进行 2D 乳房轮廓的反向投影。然后,使用基于 B 样条的 3D/3D 表面配准来近似乳房 X 光摄影的乳房压缩。对 14 个具有 19 个相应乳房 X 光片的 MRI 数据集进行了这项乳房变形模拟。通过与专家观察者识别的相应结构之间的距离进行比较来评估结果。
当对两个图像数据集进行优化的初始配准时,评估结果显示对应结构之间的平均距离为 6.46mm。如果不进行优化,精度为 9.12mm。
本文开发并测试了一种新的基于表面的方法,该方法无需使用基于有限元的方法所需的特定复杂模型,即可模拟由于乳房压缩而导致的乳房变形,具有良好的效果。模拟的压缩可以作为二维乳房 X 光片和三维 MR 图像数据之间点对线对应关系的基础。