MR imaging of articular cartilage using driven equilibrium

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Radiology

Background:

• Osteoarthritis necessitates quantitative techniques for assessing cartilage loss.
• Magnetic Resonance (MR) imaging is crucial for non-invasive cartilage evaluation.
• Existing MR techniques face challenges with cartilage's short T(2) relaxation time and low water content, often sacrificing signal brightness for contrast.

Purpose of the Study:

• To evaluate the effectiveness of Driven Equilibrium Fourier Transform (DEFT) for imaging articular cartilage.
• To compare DEFT's performance against spoiled gradient-recalled acquisition in the steady state (SPGR) and fast spin echo (FSE) methods.

Main Methods:

• A novel DEFT imaging technique was developed to enhance signal strength without full T(1) recovery.
• DEFT was implemented as a three-dimensional sequence.
• Performance was compared with SPGR and FSE sequences in terms of cartilage signal brightness and contrast with surrounding tissues.

Main Results:

• DEFT imaging provides a superior combination of bright cartilage signal and high contrast between cartilage and surrounding tissues.
• Cartilage signal-to-noise ratio (SNR) with DEFT is comparable to FSE and SPGR.
• Cartilage-synovial fluid contrast-to-noise ratio (CNR) with DEFT is up to four times greater than with FSE or SPGR.

Conclusions:

• DEFT is a valuable MR technique for imaging articular cartilage, offering significant improvements in contrast.
• The enhanced SNR and CNR of DEFT aid in more accurate assessment of cartilage loss.
• DEFT, implemented in 3D, achieves comparable coverage to other sequences within similar scan times.