Magnetic Resonance Imaging (MRI) Transverse Relaxation Time (T2) For Non-Invasive Assessment of Cartilage Composition -from Method Development to Automated Processing of Large Clinical Cohorts – A Selfie Review of 15 Years of Funding & Publication

MRI has transformed medical imaging and research by enabling detailed 3D visualization of soft tissue anatomy. But it also provides insight into biophysical, histological, and mechanical properties via quantitative MRI relaxometry (qMRI). Cartilage transverse relaxation time (T2) has emerged as probably the most robust non-invasive marker of cartilage composition and histological assessment, and of cartilage mechanical properties. As such, T2 mapping may represent a powerful tool in cartilage research, epidemiological studies, and osteoarthritis clinical trials. Our review comprises 19 original articles and 14 abstracts published over 12 years (2014-2025). It begins with technically and anatomically orientated studies, expanding to observational and interventional research in idiopathic and post-traumatic osteoarthritis. Key technical advancements include a shift from slow 2D multi-echo spin-echo (MESE) to rapid 3D high-resolution qDESS T2-imaging, an advance from manual to fully automated, AI-based segmentation, the adoption of laminar, subregional, and location-independent T2-analysis methods, and others. The review ends with a concluding paragraph, encompassing current goals and future directions of cartilage T2 imaging in research, clinical trials, and clinical practice, and emerging novel projects. This selfie review aims to summarize the progress in cartilage T2 imaging, from the method development and technical implementation initially supported by the PMU Research Fund, to its application in clinical studies and trials, supported by National and International funding bodies, such as the European Union (EU). We reviewed original articles and conference abstracts on cartilage T2 that involve contributions from our group, categorizing them by funding source and summarizing their key findings.