arXiv Machine Learning

Multiparameter Uncertainty Mapping in Quantitative Molecular MRI using a Physics-Structured Variational Autoencoder (PS-VAE)

arXiv Machine Learning
Aug 28

Quantitative mapping from conventional MRI using self-supervised physics-guided deep learning: applications to a large-scale, clinically heterogeneous dataset

This study introduces a self‑supervised, physics‑guided deep‑learning framework that converts standard clinical T1‑, T2‑, and FLAIR MRIs into quantitative T1, T2, and proton‑density maps. Trained on 4,121 scan sessions from four different 3 T scanners over six years, the method produces maps whose white‑ and gray‑matter values fall within literature ranges and shows minimal variation across scanner hardware and acquisition protocols (coefficients of variation ≤ 1.1 %). Voxel‑wise reproducibility is high, with Pearson and concordance correlation coefficients above 0.82 for T1 and T2 and mean relative differences below 6 % for T2.

By Jelmer van Lune, Stefano Mandija, Oscar van der Heide, Matteo Maspero, Martin B. Schilder, Jan Willem Dankbaar, Cornelis A. T. van den Berg, Alessandro Sbrizzi
Hugging Face Trending Papers
Jul 7

PhyMRI-SR: Toward Physics-Aware MRI Image Super-Resolution

Magnetic resonance imaging (MRI) super-resolution is vital for improving diagnostic accessibility, yet most methods treat it as a deterministic mapping from a fixed low-resolution input to a high-resolution target. This overlooks a key property of MRI acquisition physics: spatial resolution and signal-to-noise ratio (SNR) are inherently coupled, making any given low-resolution scan merely one of many possible realizations under varying acquisition trade-offs.

arXiv Computer Vision
6d ago

Retrospective macromolecular pool fraction mapping from conventional clinical MRI: a physics-guided self-supervised deep learning framework

The study introduces a physics‑guided, self‑supervised deep learning framework that estimates macromolecular pool fraction (MPF) maps directly from conventional clinical brain MRI sequences (T1‑, T2‑, and FLAIR) without requiring specialized quantitative magnetization transfer scans. By embedding an analytical two‑pool magnetization transfer model and conditioning on acquisition parameters, the method was trained on 7,705 multisite, multivendor MRI sessions and achieved consistent MPF values across vendors and protocols, with a 35.6% reduction in lesions of demyelinating disease compared to normal‑appearing white matter. Cross‑protocol validation in a healthy volunteer showed a mean voxel‑wise absolute difference of 7.7% and a concordance correlation coefficient of 0.888, demonstrating robust cross‑protocol performance.

By Jelmer van Lune, Miha Fuderer, Oscar van der Heide, Matteo Maspero, Martin B. Schilder, Jan Willem Dankbaar, Stefano Mandija, Alessandro Sbrizzi
arXiv Computer Vision
Oct 12

Stochastic Finite-Transition Learning and Exploration for Accelerated MRI Reconstruction

The paper introduces FLEX‑MRI, a method that accelerates MRI reconstruction by partitioning the recovery process into a few finite intervals defined by progressive k‑space support changes. Instead of learning fine‑grained local dynamics, FLEX‑MRI directly learns the reconstruction change across each interval and employs stochastic exploration during inference to sample alternative transition paths. Experiments on multi‑coil MRI datasets demonstrate that FLEX‑MRI outperforms competing methods while keeping computational efficiency comparable to few‑step baselines.

By Muhammad Usama Mirza, Esin \"Ozt\"urk I\c{s}{\i}k, Tolga \c{C}ukur
arXiv AI
Aug 3

Dense Temporal Contrast Synthesis via Conditioned Latent Transport

arXiv:2607. 29394v1 Announce Type: cross Abstract: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is essential for breast cancer management, but reliance on gadolinium-based contrast agents (GBCAs) restricts use in contraindicated populations, prolongs scan protocols, and presents environmental toxicity concerns.

By Smriti Joshi, Apostolia Tsirikoglou, Daniel M. Lang, Richard Osuala, Noah M\'arquez Varaa, Alejandro Guzman, Grzegorz Skorupko, Sebastian Ibarra Arregui, Lidia Garrucho, Akane Ohashi, Dimitra Ntoula, Eugen Divjak, O\u{g}uz Lafc{\i}, Jan C. Peeken, Julia A. Schnabel, Fredrik Strand, Oliver Diaz, Karim Lekadir
arXiv Machine Learning
Sep 17

Physics-Informed Sylvester Normalizing Flows for Bayesian Inference in Magnetic Resonance Spectroscopy

The paper presents a Bayesian inference framework for magnetic resonance spectroscopy (MRS) that employs Sylvester normalizing flows (SNFs) to approximate posterior distributions over metabolite concentrations. A physics-based decoder incorporates prior knowledge of MRS signal formation, ensuring realistic distribution representations. Validation on simulated 7T proton MRS data shows accurate metabolite quantification, well-calibrated uncertainties, and insights into parameter correlations and multi‑modal distributions.

By Julian P. Merkofer, Dennis M. J. van de Sande, Alex A. Bhogal, Ruud J. G. van Sloun