Three‐dimensional delayed gadolinium‐enhanced MRI of cartilage (dGEMRIC) at 1.5T and 3.0T

Abstract

Purpose To implement and validate a three‐dimensional (3D) T1 measurement technique that is suitable for delayed gadolinium (Gd)‐enhanced MRI of cartilage (dGEMRIC) and can be easily implemented with clinically available pulse sequences at 1.5T and 3.0T. Materials and Methods A 3D inversion‐recovery prepared spoiled gradient‐echo (IR‐SPGR) imaging pulse sequence with variable TR was used to implement a 3D T1 measurement protocol. The 3D T1 measurements were validated against a gold‐standard single‐slice 2D IR T1 measurement protocol in both phantoms and in vivo, in both asymptomatic volunteers and volunteers with osteoarthritis (OA). Results T1 measurements in phantoms showed a statistically significant correlation between the 2D and 3D measurements at 1.5T (R² = 0.993, P < 0.001) and 3.0T (R² = 0.996, P < 0.001). In vivo application demonstrated the feasibility of using this 3D IR‐SPGR sequence to evaluate the molecular status of articular cartilage throughout the knee joint with 0.63 × 0.63 × 3.0 mm spatial resolution within a 20‐minute acquisition, even with the measurement parameters set for the higher T1(Gd) of cartilage at 3T (range = 400–900 msec mean T1 within a region of interest (ROI) in cartilage, compared to 200–600 msec mean T1 at 1.5T). Conclusion This 3D T1 measurement protocol may prove useful for the evaluation and follow‐up of cartilage dGEMRIC indices in clinical studies of OA. J. Magn. Reson. Imaging 2006.