Can Automated 3-Dimensional Dixon-Based Methods Be Used in Patients With Liver Iron Overload?

Area of Science:

• Medical Imaging
• Radiology
• Biomedical Engineering

Background:

• Accurate liver iron concentration (LIC) quantification is crucial for managing iron overload disorders.
• Magnetic resonance imaging (MRI) offers non-invasive LIC assessment.
• Conventional 2D gradient echo (GRE)-based R2* relaxometry requires manual postprocessing.

Purpose of the Study:

• To evaluate the accuracy of 3D multiecho Dixon MRI sequences for LIC estimation.
• To compare LIC values derived from 3D Dixon sequences against 2D GRE-based R2* relaxometry.
• To determine the reliability of 3D Dixon technique across different liver iron levels.

Main Methods:

• Retrospective analysis of 158 MRI scans from 104 patients (aged 15.2 years mean).
• Utilized 1.5 T MRI scanner with both conventional T2* relaxometry and 3D multiecho Dixon sequences.
• Analyzed R2* values and corresponding LIC estimates using correlation coefficients and Bland-Altman plots.

Main Results:

• Strong correlation (r=0.83-0.92, P<0.01) between 3D Dixon and 2D GRE methods for LIC up to 3.2 mg/g.
• Weak correlation observed for liver iron levels exceeding 7 mg/g.
• 104 patients (51 male, 53 female) included in the study.

Conclusions:

• 3D multiecho Dixon MRI provides accurate LIC measurements up to 7 mg/g.
• Automated postprocessing of 3D Dixon sequences simplifies the quantification process.
• The 3D multiecho Dixon technique is a promising alternative to 2D GRE-based methods for liver iron assessment.