Storage of Frozen Sections in Paraffin Blocks.

The development of the techniques for cutting frozen sections, in particular the use of cryostat microtomes (Pearse, 1960; Cunningham, Bitensky, Chayen, and Silcox, 1960 and 1962; Goodbody, 1963 a and b; Cunningham, 1963), has resulted in sections which not only are produced routinely very rapidly but which are completely acceptable histologically. Such sections would be ideal, especially where speed is important, were it not for the problems of storing and recutting the frozen tissue should it become necessary to refer to this material at a later time. The present communication describes a method by which frozen tissue, which has been used for cryostat microtomy, can be fixed and embedded in paraffin wax for indefinite storage.