Figure 4.

Determining bone ultrastructure organization using polarized second harmonic generation (pSHG). (a) Comparison of organized wild-type (i) and disorganized osteogenesis imperfecta (oim) (ii) bone ultrastructure from 5 µm thick sections of demineralized femoral mouse bones. The images in (a(i),(ii); parallel) are taken with a polarizer angle difference of 90° with respect to the images in (a(iii),(iv); perpendicular). (Images from [109] with kind permission of SPIE.) (b) pSHG of human vertebral trabecular bone in transmission mode. The white arrows indicate the polarization direction of the incident laser beam. Mineralized collagen fibril bundles/fibres arranged in lamellae are clearly visible when aligned with the laser polarization direction (b(ii)). (Image from [4] with kind permission of Cambridge Journals.)