Protocol optimization for cardiac and liver iron content assessment using MRI: What sequence should I use?

Area of Science:

• Pediatric Radiology
• Magnetic Resonance Imaging
• Medical Physics

Background:

• Iron overload is a significant concern in children, necessitating accurate monitoring.
• Accurate estimation of iron concentration in the liver and heart is vital for managing conditions like thalassemia and sickle cell disease.
• Current MRI protocols may be lengthy and involve redundant sequences.

Purpose of the Study:

• To identify the optimal MRI protocol and sequences for assessing liver and cardiac iron concentration in pediatric patients.
• To streamline MRI protocols for iron estimation in children, reducing examination time.

Main Methods:

• Evaluation of pediatric patients (≤18 years) undergoing cardiac and liver MRI for iron estimation.
• Measurement of liver T2, liver T2*, and cardiac T2* values.
• Correlation analysis and Bland-Altman plots to compare different MRI sequences and organ measurements.

Main Results:

• Strong correlations were observed between liver T2 and T2* values (r=0.96) and between liver T2* measurements from dedicated liver and cardiac MRIs (r=0.96).
• Cardiac T2* values also showed a strong correlation (r=0.81).
• Liver and cardiac iron estimations demonstrated high agreement between dedicated and integrated MRI sequences.

Conclusions:

• MRI protocols for pediatric liver and cardiac iron assessment can be simplified.
• A single breath-hold Gradient Recalled Echo (GRE) sequence is sufficient for evaluating iron concentration in both the liver and heart in most pediatric cases.
• Simplification of MRI protocols can reduce scan time and eliminate redundant data acquisition.