PURPOSE: To evaluate the magnetic susceptibility properties of different anatomical structures within the knee joint using quantitative susceptibility mapping (QSM). METHODS: A collagen tissue model was simulated and ex vivo animal cartilage experiments were conducted at 9.4 Tesla (T) to evaluate the B0 orientation-dependent magnetic susceptibility contrast observed in cartilage. Furthermore, nine volunteers (six healthy subjects without knee @entity158 history and three @entity1 with known @entity3331 , between 29 and 58 years old) were scanned using gradient-echo acquisitions on a high-field 7T MR scanner. Susceptibility values of different tissues were quantified and diseased cartilage and meniscus were compared against that of healthy volunteers. RESULTS: Simulation and ex vivo animal cartilage experiments demonstrated that collagen fibrils exhibit an anisotropic susceptibility. A gradual change of magnetic susceptibility was observed in the articular cartilage from the superficial zone to the deep zone, forming a multilayer ultrastructure consistent with anisotropy of collagen fibrils. @entity937 caused a clear reduction of susceptibility contrast between the injured meniscus and surrounding cartilage illustrated by a loss of the sharp boundaries between the two. Moreover, QSM showed more dramatic contrast in the focal @entity528 than R2* mapping. CONCLUSION: The arrangement of the collagen fibrils is significant, and likely the most dominant source of magnetic susceptibility anisotropy. Quantitative susceptibility mapping offers a means to characterize magnetic susceptibility properties of tissues in the knee joint. It is sensitive to collagen damage or degeneration and may be useful for evaluating the status of knee diseases, such as @entity937 and @entity1844 . Magn Reson Med, 2017.    2017 International Society for Magnetic Resonance in Medicine.

Investigating magnetic susceptibility of XXXX knee joint at 7 tesla.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1844 :: ('MESH:D002357', 'Disease') :: ['cartilage disease'] @entity937 :: ('MESH:D012167', 'Disease') :: ['Meniscal tears', 'meniscal tears'] @entity3331 :: ('MESH:D007718', 'Disease') :: ['knee injury'] @entity158 :: ('MESH:D010146', 'Disease') :: ['pain'] @entity528 :: ('MESH:D009410', 'Disease') :: ['degenerated articular cartilage']
@entity1 :: (9606,Species) :: ['human']
