Improvement of the Quality of Frozen Sections from Formalin fixed Tissue
Abstract
0038-9l53/90/6501-0043$02.00/0 STAIN TECHNOLOGY Copyright 0 1990 by Williams & Wilkins Vol. 65, No. 1 Printed in U.S.A. NOTES ON TECHNIC IMPROVEMENT OF THE QUALITY FROZEN OF SECTIONSFROM FORMALIN FIXED TISSUE TOSHIHJRO KUMIKO ISHII, KASAMA AND MAYUMI KONDO, Department o f Pathology, The Research Institute for Tuberculosis and Cancer, Tohoku University, Sendai 980,Japan O.C.T. compound (OCT) (Tissue Tek Products, Ames Division, Miles Laboratories, Inc., Elkhart, IN), a water-soluble embedding medium, is widely used to prepare frozen sections from formalin fixed tissue. It works with most tissues for cutting sections less than about 10 pm thick. However, sections more than 15 pm thick of fragile specimens such as liver, or especially spleen, are as difficult to cut as in paraffin because the sections almost always shatter. Thick sections of these organs are indispensable for observing their threedimensional reticular framework. On the basis of the personal experience of one of us with Carbowax (polyethylene glycols) embedding (Mori et al. 1960), we have used OCT not only to surround specimens and bind them to the cryostat chuck, but also, before that, to infiltrate them. Consequently we were able to achieve even better results than expected. The procedure is as follows: 1) Fixed