Source:http://linkedlifedata.com/resource/umls/id/C0005597
MSH: The property of nonisotropic media, such as crystals, whereby a single incident beam of light traverses the medium as two beams, each plane-polarized, the planes being at right angles to each other. (Cline et al., Dictionary of Visual Science, 4th ed),CSP: transmission of light unequally in different directions, such as by prisms and other crystals and ordered materials.