R2 relaxometry based MR imaging for estimation of liver iron content: A comparison between two methods

Area of Science:

• Radiology
• Medical Imaging
• Biophysics

Background:

• Accurate assessment of liver iron concentration (LIC) is crucial for managing iron overload disorders.
• R2 relaxometry Magnetic Resonance Imaging (MRI) offers a non-invasive method for LIC estimation.
• Comparing in-house analysis with commercial, FDA-approved software is essential for clinical validation.

Purpose of the Study:

• To compare the reproducibility and accuracy of R2 relaxometry MRI for liver iron concentration (LIC) estimation.
• To evaluate the consistency between in-house analysis methods and FDA-approved third-party commercial results.

Main Methods:

• Utilized a 1.5T MRI scanner with multi-echo spin-echo sequences.
• Calculated R2 relaxivity values by analyzing regions of interest in the liver.
• Assessed the correlation and agreement between in-house R2-based LIC estimation and FerriScan® results using correlation coefficients and Bland-Altman plots.

Main Results:

• A total of 474 studies from 175 patients (age range 1-18 years) were analyzed.
• Excellent linearity was observed between proprietary and in-house R2 methods (r=0.87, p<0.001).
• Liver iron concentration (LIC) values reported by FerriScan® showed strong agreement with in-house R2-estimated LIC (r=1.0, p<0.001).

Conclusions:

• R2 relaxometry MRI is a reproducible technique for estimating liver iron concentration.
• Both proprietary FDA-approved commercial software and in-house analysis methods yield consistent results for LIC estimation.