Reg-APGAN: Registration-Guided Anatomy-Preserving GAN for CT-to-MR Translation.

Using abdominal computed tomography and T1-weighted magnetic resonance from 114 patients, we convert both modalities into a unified coronal space and perform hierarchical rigid registration using skeletal and multi-organ labels.

Reg-APGAN then performs 2D slice-wise translation on rigidly aligned 3D CT-MR volumes under structure-aware supervision to preserve anatomical topology.

Evaluation is performed on the full abdominal cavity, a highly deformable and challenging setting for multimodal synthesis.