Tissue Preparation
Most tissues are processed to paraffin blocks as this is the most convenient way to handle large numbers of specimens with reasonable speed and ease of sectioning. The process involves chemically altering tissue proteins to preserve the tissue structure followed by removal of all water and fats, replacing them with paraffin wax, which is then hardened and sectioned.
Although most specimens are fixed and processed, it is sometimes necessary to store a specimen for some time. This requires a preservative rather than a fixative.
