Clinical validation of T1ρ mapping for the assessment of hepatic fibrosis in patients with chronic liver disease Narine Mesropyan et al. Eur Radiol (2025) - Published online: 20 dec 2025 10.1007/s00330-025-12225-5
Liver fibrosis is one of the most important hallmarks of chronic liver disease (CLD) and plays a pivotal role from both a radiological and, even more, a clinical perspective. Traditionally, liver fibrosis assessment has relied on liver stiffness measurement (LSM) using transient elastography (FibroScan). Although widely available and easy to perform, ultrasound-based techniques are affected by several well-known pitfalls. From a radiological perspective, magnetic resonance imaging (MRI) offers whole-liver evaluation and has progressively gained a central role in non-invasive fibrosis assessment. MR elastography (MRE) is currently considered the most accurate imaging technique for fibrosis staging, with excellent correlation with histology. However, MRE requires dedicated hardware and software, increases examination time and costs, and is still not widely available. As an alternative, quantitative MRI mapping techniques, such as native T1, extracellular volume fraction (ECV), and T2 mapping, have been proposed as surrogate biomarkers of fibrosis. A major limitation of these techniques is hepatic steatosis, which is highly prevalent in CLD: in fact, fat components shorten T1 relaxation time and can undermine T1 and ECV measurements, reducing diagnostic robustness. On this background, the authors of the present study evaluated the clinical usefulness of T1ρ mapping for the assessment of hepatic fibrosis in CLD. T1ρ is sensitive to low-frequency interactions between water protons and macromolecules and therefore may better reflect extracellular matrix deposition and collagen content, making it more specific for fibrosis and less affected by fat. The diagnostic performance of T1ρ was compared with native T1, ECV, and T2 mapping, using MRE-derived liver stiffness as the reference standard. The authors conducted a prospective, single-center study by enrolling 112 patients with CLD (mean age 48 ± 16 years). The cohort included a broad spectrum of CLD etiologies, with a high prevalence of steatotic liver disease. All patients underwent multiparametric liver MRI on a 1.5 T scanner, including MRE, proton density fat fraction (PDFF), native T1, T2, ECV, and T1ρ mapping. Different stiffness cutoffs were applied according to the presence of steatosis: significant fibrosis (≥ F2) was defined as > 3.66 kPa in patients without steatosis (PDFF ≤ 5%) and > 3.14 kPa in patients with steatosis (PDFF > 5%). Regions of interest (ROIs) were manually placed in the liver parenchyma, avoiding vessels, bile ducts, and artifacts, typically sampling both lobes. ECV was calculated from pre- and post-contrast T1 values and corrected for hematocrit. All mapping parameters (T1ρ, native T1, ECV, and T2) were significantly higher in patients with significant fibrosis compared to those without. T1ρ showed the strongest statistically significant correlation with MRE-derived stiffness in the entire cohort, outperforming native T1 and ECV. Importantly, in patients with hepatic steatosis, the correlation of native T1 with stiffness dropped markedly, whereas T1ρ maintained a moderate-to-strong correlation. From a diagnostic perspective, T1ρ achieved the highest AUC for detecting significant fibrosis in the whole cohort [AUC = 0.90 (95% CI: 0.84–0.96)], with 84.6% sensitivity (73.9–91.4) and 91.5% specificity (80.1–96.6). Moreover, in the subgroup with steatosis, T1ρ remained robust [AUC = 0.87 (95% CI: 0.77–0.97)], with 79.3% sensitivity (61.6–90.2) and 91.3% specificity (73.2–98.5), significantly outperforming native T1 and showing better performance than ECV. Conversely, T2 mapping showed limited correlation with stiffness and poor diagnostic performance, due to the confounding influence of inflammation, fat, and fibrosis. This study supports T1ρ mapping as a promising MRI biomarker for hepatic fibrosis, particularly in patients with coexisting steatosis, where conventional T1 and ECV mapping tend to lose accuracy. From a radiologist’s perspective, the main added value of T1ρ is its relative robustness to fat-related confounding, which is highly relevant in daily practice given the high prevalence of metabolic dysfunction–associated steatotic liver disease (MASLD). Limitations of this study include the lack of histopathological correlation and the single-vendor, single-field-strength implementation, which may limit generalizability. Further multicenter studies and technical standardization are needed to guarantee wider clinical application. In conclusion, even if MRE remains the reference standard for non-invasive fibrosis assessment, T1ρ mapping could represent a valuable alternative in centers without access to MRE, or as part of a comprehensive multiparametric MRI protocol. Potential future applications include fibrosis risk stratification, longitudinal monitoring, and treatment response assessment. |
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