A relaxometry method that emphasizes practicality and availability.

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Physics
• Quantitative Imaging

Background:

• Quantitative mapping of MRI parameters like T1 and T2 is crucial for diagnostics.
• Existing methods often require specialized MRI sequences or lengthy scan times, limiting clinical applicability.
• There is a need for practical, widely accessible methods for accurate MRI parameter mapping.

Purpose of the Study:

• To develop and validate a novel, practical method for quantitative mapping of main MRI parameters (T1, T2, and M0).
• To ensure joint mapping of MRI parameters for improved spatial alignment.
• To offer flexible tradeoffs between scan time and image quality.

Main Methods:

• The proposed method utilizes a multi-shot spin-echo (SE) echo-planar imaging (EPI) sequence.
• Signal equations were derived, and solution strategies were developed.
• Validation involved comparison with reference relaxometry methods in phantoms and in vivo imaging of 3 neuroradiology patients.

Main Results:

• Bland-Altman analysis showed minimal bias and acceptable limits of agreement for T2 mapping compared to 2D SE.
• T1 mapping demonstrated comparable mean relative error to reference methods (inversion-recovery SE and MOLLI).
• The method allows for adjustable scan times through echo train length manipulation.

Conclusions:

• The developed MRI method offers a practical and readily available alternative for quantitative T1 and T2 mapping.
• Its performance is comparable to established relaxometry techniques.
• The approach enhances the accessibility of quantitative MRI in clinical settings.