Multi-parametric T₂ * magnetic resonance fingerprinting using variable echo times

Area of Science:

• Biomedical Imaging
• Quantitative MRI
• Medical Physics

Background:

• Quantitative imaging biomarkers are crucial for diagnosing diseases like cancer and neurodegenerative disorders.
• T1, T2, and T2* relaxation times are sensitive to tissue properties and contrast agent effects.
• Simultaneous multi-parametric mapping can enhance tissue change detection.

Purpose of the Study:

• To incorporate T2* relaxation into the magnetic resonance fingerprinting (MRF) framework.
• To develop a novel method for fitting and correcting off-resonance effects in multi-parametric MRF.
• To evaluate the feasibility and accuracy of the enhanced MRF technique.

Main Methods:

• Modified MRF framework incorporating variable echo times (TE) to acquire T2* data.
• Comparison of incremental and golden angle spiral k-space trajectories.
• Validation using simulated phantom data, agar phantoms, and in vivo brain scans of healthy volunteers.

Main Results:

• The enhanced MRF method successfully acquired T1, T2, and T2* relaxation time constants simultaneously.
• Golden angle spiral rotation demonstrated reduced inaccuracy from off-resonance effects.
• Strong correlations were observed between conventional and MRF-derived relaxation times (T1, T2, T2*) in phantoms and volunteers.

Conclusions:

• T2* relaxation can be effectively integrated into the MRF framework using variable echo times.
• The developed method provides accurate multi-parametric quantitative imaging.
• This technique holds promise for improved disease detection and monitoring in oncology and neurology.