Three-dimensional Multi-parameter Mapping of Relaxation Times and Susceptibility Using Partially RF-spoiled Gradient...

Area of Science:

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

Background:

• MR parameter mapping provides crucial tissue characteristics like relaxation times and proton density (PD).
• Quantitative susceptibility mapping shows promise for early detection of neurological disorders.
• Simultaneous mapping of multiple MR parameters can enhance diagnostic capabilities.

Purpose of the Study:

• To develop a novel MR quantitative parameter mapping (QPM) method.
• To simultaneously map four tissue parameters (T1, T2*, PD, susceptibility) and B1.
• To validate the accuracy and repeatability of the developed QPM method.

Main Methods:

• Utilized a 3D partially RF-spoiled gradient echo (pRSGE) sequence.
• Varied scan parameters (flip angle, RF-pulse phase increment, TR, TE) for multiple image acquisitions.
• Employed Bloch simulations and least-squares fitting for numerical intensity function estimation.

Main Results:

• Achieved 1.1-mm isotropic whole-brain coverage in approximately 12 minutes.
• Demonstrated high accuracy and repeatability in phantom experiments.
• Showcased accuracy comparable to conventional methods in volunteer scans.

Conclusions:

• The developed QPM method enables simultaneous mapping of T1, T2*, PD, susceptibility, and B1.
• The method's scan time is suitable for human subjects.
• QPM offers a potentially valuable tool for clinical diagnosis and disease quantification.