用无约束优化薄板样条实现平滑的医学图像弹性配准

Medical Image Elastic Registration Smoothed by Unconstrained Optimized Thin-plate Splines

医学图像弹性配准是医学图像处理的一个重要研究方向。目前采用的方法多是手动选择对应标记点 ,然后用薄板样条插值方法计算配准变换。由于对应点的选取总是存在误差 ,所以配准的准确性受到影响 ,而且手动选点操作繁杂、耗时大。为此 ,我们根据最优化理论 ,改进了薄板样条插值方法 ,并在此基础上采用了一种自动标记点选择方法。将这两者结合 ,我们得到了一种自动、准确、鲁棒性好的配准方法 ,运用此方法进行医学图像的弹性配准 。

Elastic registratioin of medical image is an important subject in medical image processing. Previous work has concentrated on selecting the corresponding landmarks manually and then using thin plate spline interpolating to gain the elastic transformation. However, the landmarks extraction is always prone to error, which will influence the registration results. Localizing the landmarks manually is also difficult and time consuming. We the optimization theory to improve the thin plate spline interpolation, and based on it, used an automatic method to extract the landmarks. Combining these two steps, we have proposed an automatic,exact and robust registration method and have gained satisfactory registration results.