Local T2 distribution measurements with DANTE-Z slice selection.

Area of Science:

• Magnetic Resonance Imaging
• Materials Science
• Nuclear Magnetic Resonance Spectroscopy

Background:

• Accurate measurement of T(2) relaxation times is crucial for characterizing various materials.
• Existing Magnetic Resonance Imaging (MRI) techniques for T(2) mapping can be limited in samples with short relaxation times.

Purpose of the Study:

• To present a novel Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence integrated with a DANTE-Z slice selection scheme.
• To enable spatially-resolved measurement of T(2) distributions in samples with short T(2) values.

Main Methods:

• Implementation of a CPMG pulse sequence combined with a DANTE-Z slice selection method.
• Utilizing sinc-modulated pulses within the DANTE-Z train to select a quasi-rectangular slice (<0.8 cm width).
• Arbitrary positioning of the selected slice along a 6-cm sample.

Main Results:

• Achieved spatially-resolved T(2) distributions with quality comparable to bulk CPMG measurements.
• Demonstrated a lower T(2) limit of approximately 0.5 ms.
• The selected slice width was less than 0.8 cm.

Conclusions:

• The developed pulse sequence is a valuable supplement or alternative to MRI for T(2) mapping.
• It is particularly effective for short relaxation time samples like saturated rocks, wood, and rubbers.
• The technique is suitable when T(2) measurements are needed at a few specific positions with ~1 cm resolution.