High-speed 3T MR spectroscopic imaging of prostate with flyback echo-planar encoding

Area of Science:

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

Background:

• Prostate MR spectroscopic imaging (MRSI) at 3 Tesla (3T) offers higher spatial resolution than 1.5T.
• Conventional phase-encoding MRSI at 3T leads to prolonged acquisition times for full gland coverage.
• Longer scan times can limit clinical utility and patient comfort.

Purpose of the Study:

• To accelerate the acquisition of high-resolution prostate MRSI data at 3T.
• To evaluate the feasibility of using flyback echo-planar readout trajectories for prostate MRSI.
• To reduce overall prostate MRI/MRSI examination duration.

Main Methods:

• Incorporation of flyback echo-planar readout trajectories into a Malcolm Levitt's composite-pulse decoupling sequence (MLEV)-point-resolved spectroscopy sequence (PRESS).
• Acquisition of large array (16 x 16 x 8) MRSI data with high spatial resolution (0.154 cm(3)).
• Eight-fold acceleration of MRSI acquisition time, achieving results in 8.5 minutes.

Main Results:

• Artifact-free, high-quality MRSI data acquired in nine prostate cancer patients.
• Demonstrated eight-fold acceleration of MRSI acquisition.
• Achieved high spatial resolution (0.154 cm(3)) within a clinically feasible timeframe.

Conclusions:

• Flyback echo-planar trajectories significantly shorten prostate MRSI acquisition times at 3T.
• The technique is robust and suitable for clinical settings due to easy data reconstruction.
• Reduced scan times enhance clinical workflow, allowing for longer repetition times or additional MR acquisitions.