Plastic embedding procedure for 15 microns sections of large undecalcified tissue blocks.

A method is described that produces sections (15 microns) of large specimens (with dimensions up to 140 x 100 x 200 mm). They are suitable for comparison to CT images of that specimen and can be used as a basis for three-dimensional reconstructions. Frozen unfixed parts of the human body are embedded in polyurethane and scanned with CT. Undecalcified slices, 6 mm thick, of these specimens are cut with a bandsaw. These slices are successfully embedded in polyester resin by means of fixation, dehydration, and subsequent impregnation with this resin. Sections of 15 microns are obtained by cutting the trimmed and sandpapered polyester blocks with an LKB multirange microtome. They are collected on adhesive tape and stained according to Weigert-Azan, sealed between adhesive acetate sheets and photographed on colour slide film. As an example photographs of sections of the human elbow and lumbar spine region are presented.