GuidedMorph: Two-Stage Deformable Registration for Breast MRI
Journal:
arXiv
Published Date:
May 19, 2025
Abstract
Accurately registering breast MR images from different time points enables
the alignment of anatomical structures and tracking of tumor progression,
supporting more effective breast cancer detection, diagnosis, and treatment
planning. However, the complexity of dense tissue and its highly non-rigid
nature pose challenges for conventional registration methods, which primarily
focus on aligning general structures while overlooking intricate internal
details. To address this, we propose \textbf{GuidedMorph}, a novel two-stage
registration framework designed to better align dense tissue. In addition to a
single-scale network for global structure alignment, we introduce a framework
that utilizes dense tissue information to track breast movement. The learned
transformation fields are fused by introducing the Dual Spatial Transformer
Network (DSTN), improving overall alignment accuracy. A novel warping method
based on the Euclidean distance transform (EDT) is also proposed to accurately
warp the registered dense tissue and breast masks, preserving fine structural
details during deformation. The framework supports paradigms that require
external segmentation models and with image data only. It also operates
effectively with the VoxelMorph and TransMorph backbones, offering a versatile
solution for breast registration. We validate our method on ISPY2 and internal
dataset, demonstrating superior performance in dense tissue, overall breast
alignment, and breast structural similarity index measure (SSIM), with notable
improvements by over 13.01% in dense tissue Dice, 3.13% in breast Dice, and
1.21% in breast SSIM compared to the best learning-based baseline.
