Quantitative susceptibility mapping (QSM) for human in-vivo renal mass differentiation and kidney stone characterization

• Applicant: Dr. Jannis Hanspach
• Subject Area: Medical Physics, Biomedical Technology
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 563818801

The objective of this project is to evaluate the potential of in-vivo quantitative susceptibility mapping (QSM), a complex magnetic resonance imaging (MRI) post-processing technique, to depict and classify kidney stones and to characterize renal masses, with a focus on the differentiation between benign angiomyolipoma with minimal fat (AMLwMF) and non-clear renal cell carcinomas (RCCs). To achieve these goals, the project is structured into three work packages (WPs): In WP1, advanced sequence methods for kidney QSM will be developed and optimized, including single-breath-hold, respiratory-gated and radial sequences. These sequences will be tested in phantom and volunteer measurements. The aim is to acquire reproducible and high-quality phase maps for kidney QSM. In WP2, a conventional QSM reconstruction pipeline with an integrated fat-water separation algorithm will be optimized for our data sets from WP1. Furthermore, a neural QSM reconstruction network will be trained on synthetic phase and susceptibility maps representative of our acquired data sets. The aim of this WP is to obtain high-quality susceptibility maps, which can reveal subtle differences in magnetic susceptibility. Finally, in WP3, a patient study involving 40 patients will be conducted. Twenty patients with unclear renal masses undergoing clinical kidney MR imaging will be measured. The presence of calcifications and/or intralesional hemorrhage will be assessed by a trained radiologist. The aim is to explore the diagnostic value of our kidney QSM method in comparison to state-of-the-art clinical MRI of renal masses. Similarly, 20 patients with confirmed kidney stones will be measured using QSM and the visibility of the kidney stones will be assessed by a trained radiologist. The aim is to compare our kidney QSM approach to other MRI modalities and CT imaging and to explore whether QSM can serve as a radiation-free alternative method for kidney stone tracking and characterization.

• DFG Programme: Research Grants