MRI-Based Assessment of Hepatic Iron Overload

Hepatic iron overload arises when excessive iron accumulates in the liver, commonly as a consequence of hereditary haemochromatosis, transfusional therapies or chronic liver disease. Magnetic resonance imaging (MRI) offers a non-invasive means of quantifying liver iron concentration by exploiting the paramagnetic properties of iron that accelerate transverse relaxation. Techniques such as R2* and T2* relaxometry, chemical shift imaging and quantitative susceptibility mapping (QSM) enable clinicians to measure iron-induced signal decay with high reproducibility. Modern scanners at 1.5 T and 3 T field strengths can capture multi-echo gradient-echo sequences that are post-processed to derive relaxation rates, which correlate with biopsy-derived iron levels. Standardised acquisition protocols and calibration against reference methods have advanced MRI from a research tool into routine clinical practice, improving diagnosis, treatment planning and longitudinal monitoring of chelation therapies. As a result, MRI-based assessment of liver iron has become integral to the management of patients at risk of end-stage fibrosis and cirrhosis.

Research from Nature Portfolio

Recent clinical investigations have refined the use of T2* mapping at 3 T MRI to track changes in cardiac and hepatic iron load in patients with thalassaemia before and after haematopoietic stem cell transplantation, demonstrating significant improvements in iron clearance beyond 24 months post-transplant. In parallel, normative R2* reference values have been established in healthy volunteers using 1.5 T MRI, defining upper thresholds for liver iron indices in a young adult cohort and providing critical baselines against which pathological elevations can be gauged.

MRI-Based Assessment of Hepatic Iron Overload publication trend

The graph below shows the total number of articles in mri-based assessment of hepatic iron overload across all publications each year (not limited to Nature Index journals).

Technical terms

R2* relaxometry: Measurement of the effective transverse relaxation rate reflecting signal decay accelerated by iron deposits.

T2* relaxation time: Reciprocal of R2*, indicating the time constant for transverse magnetisation loss in the presence of inhomogeneities.

Dixon sequence: MRI technique that separates water and fat signals by acquiring echoes at different phase shifts.

Quantitative Susceptibility Mapping (QSM): Post-processing method that computes tissue magnetic susceptibility to infer iron concentration.

Ultrashort Echo Time (UTE): MRI sequence capturing signals with very short echo times, useful for tissues with rapid signal decay.

Haematopoietic Stem Cell Transplantation (HSCT): Procedure replacing diseased bone marrow, which can impact systemic iron burden.

References

1. Using artificial intelligence to improve body iron quantification: A scoping review. Blood Reviews (2023).
2. Cascade of Denoising and Mapping Neural Networks for MRI R2* Relaxometry of Iron-Loaded Liver. Bioengineering (2023).
3. Computed Tomography and Magnetic Resonance Imaging in Liver Iron Overload: From Precise Quantification to Prognosis Assessment. Biomedicines (2024).
4. Magnetic resonance imaging assessment of the changes of cardiac and hepatic iron load in thalassemia patients before and after hematopoietic stem cell transplantation. Scientific Reports (2023).
5. Value of liver iron concentration in healthy volunteers assessed by MRI. Scientific Reports (2020).
6. Practical guide to quantification of hepatic iron with MRI. European Radiology (2019).
7. Biopsy-based calibration of T2* magnetic resonance for estimation of liver iron concentration and comparison with R2 Ferriscan. Journal of Cardiovascular Magnetic Resonance (2014).