The sediment is usually examined using brightfield microscopy and subdued light (some structures will be missed if there is too much light in the field). Fine focus throughout the examination to identify structures in different focal planes.
Scan the slide on low power (100X total magnification) for quantification of casts, crystals and elements that are present in only a few fields. Use high power (400X total magnification) to identify casts and count red blood cells (RBCs), white blood cells (WBCs), and epithelial cells.
Staining may be helpful in the identification of some cells and casts. Supravital stains that may be used include Sternheimer-Malbin and 0.5% toluidine blue.
If available, phase-contrast microscopy enhances the identification of some sediment elements, particularly those that have a very low refractive index and may be missed using brightfield microscopy (eg, some casts).
Polarized light enhances the identification of lipids and some crystals.