A novel low-rank reconstruction framework for precise fat-tumor discrimination in diffusion-weighted MRI

<ns3:p>Background Diffusion-weighted MRI (DWI) offers a non-invasive approach to detect tumors based on water mobility differences from surrounding tissue. However, reliably discriminating malignancies from benign adipose remains challenging, especially in anatomical regions with abundant fat. The biophysical similarities between tumors and lipid signals create signal ambiguities that limit diagnostic accuracy using conventional reconstruction techniques. Methods We propose a novel low-rank reconstruction framework that combines accelerated diffusion data acquisition, structured low-rank regularization, and deep learning-assisted radiomic analysis to enhance fat-tumor discrimination in DWI. Simultaneous multi-slice imaging and controlled aliasing enable high spatiotemporal resolution while maintaining feasible scan times. A data-driven annihilating filter kernel is then learned from the undersampled data, imposing implicit low-rank constraints to suppress confounding fat signals while retaining tumor texture details during k-space reconstruction. Subsequent radiomic analysis extracts morphological imaging biomarkers from the reconstructed volumes to identify distinctive tumor signatures. Results Comprehensive validation on clinical DWI datasets demonstrates the improved fat-tumor discrimination capability of the proposed framework compared to conventional techniques. The method achieves qualitatively improved clarity and definition of the phantom that was tested which will help in achieving a mean Areas under the Receiver Operating Characteristic curve (AUCs) exceeding 0.80 for distinguishing malignant lesions from adipose tissue. Case studies illustrate how better signal specificity enables more confident clinical decisions. Conclusions The integrated low-rank reconstruction and radiomic analysis framework offers a promising solution to the longstanding problem of fat-tumor ambiguity in diffusion MRI. By unleashing the full diagnostic potential of DWI, this methodology can enhance non-invasive cancer screening and monitoring across diverse patient populations and anatomical regions.</ns3:p>