Validation of a dynamic MR elastography technique customized for in vitro biomechanical assessment of articular cartilage under high frequency cyclical shear
Lopez O, Ehman R, Manduca A
Assessment of internal mechanical properties in articular cartilage by dynamic MR Elastography (MRE) requires customized methods for adequate generation and visualization of high-frequency (> 1 kHz) propagating shear waves. Sensitivity and repeatability of the technique were validated using sets of homogeneous, cartilage-mimicking, small and stiff dual-layered phantoms (2.5 mm thick per layer) made of wirosil silicone. Results demonstrated the sensitivity of customized dynamic MRE to detect differences in mechanical properties within small-stiff, multilayered, cartilage mimicking materials. Dynamic MRE of bovine articular cartilage also assessed differences in mechanical properties between superficial- and deep-layers.