Polarized reflectance from articular cartilage depends upon superficial zone collagen network microstructure

Abstract

Polarized reflectance from articular cartilage involves light scattering dependent on surface features, sub-surface optical properties, and collagen birefringence. To understand how surface roughness, zonal collagen microstructure, and chondrocyte organization contribute to polarized reflectance signals, experiments were conducted on bovine cartilage explants and osteochondral cores to compare polarized reflectance texture with split lines and relate these signals to cartilage zonal features and chondrocyte distribution. Texture parameter sensitivity to articular surface damage was determined from polarized reflectance maps and optimized to detect surface damage. Results indicate that polarized reflectance texture predominantly derives from the superficial zone collagen network, while the parameter average value also depends on surface roughness and total cartilage thickness.

Articular Cartilage—From Basic Science Structural Imaging to Non-Invasive Clinical Quantitative Molecular Functional Information for AI Classification and Prediction

“…Interestingly, the results indicated that polarized reflectance textures were derived from the superficial zone collagen network, while average values also depended on surface roughness and cartilage thickness. In contrast, the high correlation of polarized reflectance texture with split lines did not extend to a clear relationship with the organization of chondrocytes in the superficial zone, suggesting that polarized reflectance depends more upon collagen microstructure than scattering from cells [155]. Thus, polarized reflectance imaging appears to be valuable for collagen network imaging and surface roughness.…”

“…In another recent study, a polarized reflectance imaging setup as described in [154] was used to generate polarized reflectance maps to study how surface roughness, zonal collagen microstructure, and chondrocyte organization contribute to polarized reflectance signals in bovine articular cartilage [155]. Interestingly, the results indicated that polarized reflectance textures were derived from the superficial zone collagen network, while average values also depended on surface roughness and cartilage thickness.…”