Development of a live tissue microtome: reflections of an amateur machinist.

Live circular tissue slices of nearly identical diameter and thickness can be generated from most tissues by the use of two instruments; a coring tool to cut cylindrical tissue cores which are subsequently sliced by a microtome into thin circular sections 5-8 mm in diameter and 50-300 microns thick. The sections are of very similar geometry permitting direct comparisons without normalization. Both instruments operate submerged in a cold isotonic medium that caries the cut slices outside the microtome. The slices are cut by a rapidly oscillating disposable Gillette blade mounted at an angle of 20 degrees to the vertical main axis of the tissue core. The latter is advanced against the oscillating blade by a weighted plunger pushing it against a screw adjustable limit plate that defines the desired slice thickness. Both instruments can be sterilized and slices can be obtained at a rate of approximately one every ten seconds.