Eckstein F et al. (2005) Accuracy and precision of quantitative assessment of cartilage morphology by magnetic resonance imaging at 3.0 T. Arthritis Rheum 52: 3132–3136

Quantitative MRI of articular cartilage has made it possible to determine cartilage morphology with a high level of accuracy and reproducibility, but has so far been limited to a field strength of 1.5 T. Eckstein et al. wondered whether the improved signal-to-noise ratio and spatial resolution obtainable with 3.0 T MRI would result in more precise measurements of cartilage morphology. They also investigated the quantitative effect of a smaller than standard partition volume in conjunction with the increased field strength.

Magnetic resonance images of one knee of each of 30 female subjects aged 45 years or over were obtained using 1.5 T and 3.0 T scanners. Half the participants had mild-to-moderate osteoarthritis; half were healthy controls. Scans were obtained at 1.5 T with a 1.5 mm partition thickness (standard), at 3.0 T with a 1.5 mm partition thickness, and at 3.0 T with a 1.0 mm partition thickness. Proprietary software was used to determine the volume, thickness, and surface area of the cartilage plates. Measurements at the different field strengths correlated well (correlation coefficients ranged from 0.9 to 0.99), but precision error was smallest with a 1.0 mm partition thickness at 3.0 T (2.1% and 2.0% for cartilage volume and thickness, respectively).

The authors conclude that imaging a 1.0 mm partition thickness at 3.0 T might increase detection of changes in cartilage and determine whether treatment with structure-modifying drugs is effective.