DMD-augmented Unpaired Neural Schrödinger Bridge for Ultra-Low Field MRI Enhancement

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kim, Youngmin, Shin, Jaeyun, Kim, Jeongchan, Lee, Taehoon, Kim, Jaemin, Hsu, Peter, Veraart, Jelle, Ye, Jong Chul
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910041452314624
author Kim, Youngmin
Shin, Jaeyun
Kim, Jeongchan
Lee, Taehoon
Kim, Jaemin
Hsu, Peter
Veraart, Jelle
Ye, Jong Chul
author_facet Kim, Youngmin
Shin, Jaeyun
Kim, Jeongchan
Lee, Taehoon
Kim, Jaemin
Hsu, Peter
Veraart, Jelle
Ye, Jong Chul
contents Ultra Low Field (64 mT) brain MRI improves accessibility but suffers from reduced image quality compared to 3 T. As paired 64 mT - 3 T scans are scarce, we propose an unpaired 64 mT $\rightarrow$ 3 T translation framework that enhances realism while preserving anatomy. Our method builds upon the Unpaired Neural Schrödinge Bridge (UNSB) with multi-step refinement. To strengthen target distribution alignment, we augment the adversarial objective with DMD2-style diffusion-guided distribution matching using a frozen 3T diffusion teacher. To explicitly constrain global structure beyond patch-level correspondence, we combine PatchNCE with an Anatomical Structure Preservation (ASP) regularizer that enforces soft foreground background consistency and boundary aware constraints. Evaluated on two disjoint cohorts, the proposed framework achieves an improved realism structure trade-off, enhancing distribution level realism on unpaired benchmarks while increasing structural fidelity on the paired cohort compared to unpaired baselines.
format Preprint
id arxiv_https___arxiv_org_abs_2603_03769
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle DMD-augmented Unpaired Neural Schrödinger Bridge for Ultra-Low Field MRI Enhancement
Kim, Youngmin
Shin, Jaeyun
Kim, Jeongchan
Lee, Taehoon
Kim, Jaemin
Hsu, Peter
Veraart, Jelle
Ye, Jong Chul
Computer Vision and Pattern Recognition
Artificial Intelligence
Machine Learning
Ultra Low Field (64 mT) brain MRI improves accessibility but suffers from reduced image quality compared to 3 T. As paired 64 mT - 3 T scans are scarce, we propose an unpaired 64 mT $\rightarrow$ 3 T translation framework that enhances realism while preserving anatomy. Our method builds upon the Unpaired Neural Schrödinge Bridge (UNSB) with multi-step refinement. To strengthen target distribution alignment, we augment the adversarial objective with DMD2-style diffusion-guided distribution matching using a frozen 3T diffusion teacher. To explicitly constrain global structure beyond patch-level correspondence, we combine PatchNCE with an Anatomical Structure Preservation (ASP) regularizer that enforces soft foreground background consistency and boundary aware constraints. Evaluated on two disjoint cohorts, the proposed framework achieves an improved realism structure trade-off, enhancing distribution level realism on unpaired benchmarks while increasing structural fidelity on the paired cohort compared to unpaired baselines.
title DMD-augmented Unpaired Neural Schrödinger Bridge for Ultra-Low Field MRI Enhancement
topic Computer Vision and Pattern Recognition
Artificial Intelligence
Machine Learning
url https://arxiv.org/abs/2603.03769