Fast multivoxel two-dimensional spectroscopic imaging at 3 T.

Area of Science:

• Magnetic Resonance Imaging
• Spectroscopic Imaging
• Medical Physics

Background:

• Clinical utility of multivoxel 2D chemical shift imaging depends on scan time and detectable metabolite peaks.
• Optimizing k-space sampling schemes is crucial for reducing minimum imaging time.
• Spiral-based readout gradients offer simultaneous data acquisition in three k-space dimensions, potentially shortening scan times.

Purpose of the Study:

• To implement and evaluate a 3-T spiral-based multivoxel 2D spectroscopic imaging sequence using the PRESS excitation scheme.
• To demonstrate the feasibility of acquiring in vivo data within a clinically relevant scan time.
• To assess the performance of the sequence for various applications including brain and prostate imaging.

Main Methods:

• Implementation of a 3-T spiral-based multivoxel 2D spectroscopic imaging sequence with PRESS excitation.
• Utilizing spiral-based readout gradients for simultaneous k-space sampling in three dimensions (k(x), k(y), k(f(2))).
• Designing protocols to achieve data acquisition within a 17-minute scan time.

Main Results:

• Successful implementation of the 3-T spiral-based multivoxel 2D spectroscopic imaging sequence.
• Demonstrated good performance with preliminary in vivo data acquisition.
• Acquired data for brain glutamate imaging, metabolite T(2) quantification, and high-spatial-resolution prostate spectroscopic imaging within 17 minutes.

Conclusions:

• Spiral-based multivoxel 2D spectroscopic imaging at 3 T is a viable technique for clinical applications.
• The implemented sequence effectively reduces scan time, enabling practical use in environments with time constraints.
• The method shows promise for advanced neuroimaging and prostate cancer assessment through detailed metabolite analysis.