Liver Iron Content Determination Using a Volumetric Breath-Hold Gradient-Echo Sequence With In-Line R₂ * Calculation

Area of Science:

• Radiology
• Medical Imaging
• Hepatology

Background:

• Liver iron overload is a serious condition with no physiological excretion mechanism.
• Chelation therapy is indicated for elevated iron levels, requiring regular monitoring of liver iron content (LIC).
• Existing MRI methods for LIC assessment are time-consuming and costly.

Purpose of the Study:

• To correlate liver R2* values from a rapid 3D breath-hold multigradient echo (GRE) MRI sequence with reference liver iron content (LIC) values.
• To evaluate an accelerated MRI technique for efficient LIC determination.

Main Methods:

• A prospective study involving 117 patients suspected of iron overload.
• Utilized a 3D breath-hold multigradient echo (GRE) MRI sequence with parallel imaging acceleration and in-line R2* calculation.
• Compared MRI-derived LIC with a regulatory-approved, longer scan time method for reference values.

Main Results:

• Excellent interobserver agreement (ICC=0.99) was achieved.
• Demonstrated good correlation (R²=0.89) and congruence between MRI-derived LIC and reference LIC values.
• Achieved high sensitivity and specificity for clinically relevant LIC thresholds (e.g., 1.0/0.95 for 7 mg/g).

Conclusions:

• Accelerated MRI with in-line R2* map generation significantly reduces acquisition time for LIC determination.
• This method maintains diagnostic accuracy, offering a more efficient approach for managing iron overload.
• The findings support the use of this rapid MRI technique for routine patient monitoring.