Fast 3D 1H spectroscopic imaging at 3 Tesla using spectroscopic missing-pulse SSFP with 3D spatial preselection

Area of Science:

• Magnetic Resonance Imaging
• Spectroscopic Imaging
• Biomedical Engineering

Background:

• Fast acquisition techniques are crucial for 3D (1)H MR spectroscopic imaging (SI) in clinical practice.
• Current methods require adequate spatial resolution within acceptable measurement times to identify metabolic changes in human tissue.
• Existing techniques may involve complex data processing or separate water/lipid suppression methods.

Purpose of the Study:

• To introduce a novel, fast pulse sequence for 3D (1)H SI.
• To evaluate the performance of the proposed "spectroscopic missing-pulse SSFP" (spMP-SSFP) sequence.
• To demonstrate the feasibility of spMP-SSFP for in vivo metabolic imaging.

Main Methods:

• Development of a novel fast pulse sequence, spMP-SSFP, based on steady-state free precession (SSFP).
• Combination of 3D spatial preselection with full spin echo (SE) acquisition to eliminate phase correction.
• Application of the sequence to a phantom and healthy human brains at 3 Tesla.

Main Results:

• Metabolic images were acquired with a spatial resolution of 1.8 cm(3) in approximately 6 minutes.
• 3D spatial preselection was achieved with spMP-SSFP, despite a lower SNR per unit measurement time.
• The method demonstrated robustness, requiring minimal user interaction and no separate water/lipid suppression techniques.

Conclusions:

• spMP-SSFP is a robust and fast 3D MR spectroscopic imaging method.
• The sequence simplifies data processing and reduces user interaction for clinical applications.
• spMP-SSFP facilitates efficient metabolic assessment in human brain tissue.