Simultaneous high-resolution cardiac T₁ mapping and cine imaging using model-based iterative image reconstruction.

Area of Science:

• Cardiovascular Magnetic Resonance Imaging
• Medical Imaging Physics

Background:

• Cardiac T1 mapping is crucial for assessing myocardial tissue characteristics.
• Current methods often require long scan times or multiple breath-holds, limiting clinical utility.
• Simultaneous acquisition of T1 maps and cine images can improve diagnostic efficiency.

Purpose of the Study:

• To develop and evaluate a novel cardiac MRI technique for simultaneous high-resolution T1 mapping and cine imaging.
• To achieve this within a single breath-hold using continuous golden ratio radial acquisition and model-based reconstruction.
• To assess the feasibility and accuracy of the method in phantoms and healthy subjects.

Main Methods:

• Continuous golden ratio-based radial acquisition with interleaved inversion pulses.
• Model-based iterative image reconstruction for native T1 maps (diastole and systole).
• kt-SENSE reconstruction for cine images with 30 cardiac phases.

Main Results:

• Accurate T1 measurements in phantom studies (R² > 0.99) with heart rate independence.
• In vivo T1 values showed no significant difference between systole and diastole.
• The proposed method yielded longer T1 times compared to MOLLI, except in lateral segments.
• Cine images demonstrated consistent dark-blood contrast and comparable functional assessment to Cartesian scans.

Conclusions:

• The developed approach enables simultaneous acquisition of high-resolution diastolic and systolic T1 maps with cine images in 16 seconds.
• This technique significantly enhances cardiac MRI scan efficiency.
• It holds potential for improved clinical diagnosis and assessment of cardiac conditions.