Quantitative MRI in pancreatic and liver diseases From technical optimization to clinical application

Quantitative MRI techniques provide non-invasive biomarkers of tissue properties, with potential to inform personalized treatment strategies. This thesis investigates the optimization, validation, and clinical application of multiple quantitative MRI methods in pancreatic and liver diseases.
In pancreatic ductal adenocarcinoma (PDAC), MR elastography (MRE) was optimized and shown to reliably quantify pancreatic stiffness and viscosity, revealing increased values in tumors compared to non-tumorous tissue.
Furthermore, dynamic contrast-enhanced MRI (DCE-MRI) acquisition and reconstruction were systematically optimized for abdominal applications. Phantom and in vivo scans demonstrate that tailored protocols enable accurate pharmacokinetic parameter estimation while maintaining image quality.
Histopathological validation of quantitative MRI techniques in PDAC revealed that microvascular density correlated with intravoxel-incoherent motion diffusion-weighted (IVIM-DWI) and T2* metrics, while collagen density correlated with T2*, supporting their value as tissue biomarkers.
Clinical utility of these techniques in PDAC patients is shown in a multicenter phase I/II clinical trial evaluated combined chemotherapy and LDE225 in metastatic PDAC patients. Quantitative MRI demonstrated treatment-induced increases in diffusion and perfusion parameters, with IVIM-DWI showing prognostic potential for overall survival.
Beyond pancreatic cancer, quantitative MRI was applied to metabolic dysfunction-associated steatotic liver disease (MASLD). In a cohort of 91 patients, quantitative MRI parameters, particularly when combined with laboratory markers, differentiated disease activity, fibrosis, and severity stages with strong correlation to histopathology.
The findings of this thesis underscore the value of quantitative MRI for characterizing tissue microenvironments in pancreatic and liver diseases. While technical and translational challenges remain, optimized protocols and histopathological validation advance the clinical integration of these techniques.