A simple method of measuring the thickness of semi-thin and ultra-thin sections.

The exact measurement of the thickness of semi-thin and ultra-thin sections is of importance for some stereological methods. Although section thickness can be measured with great precision and accuracy using suitable microinterferometers, such instruments are expensive and not easily available to many laboratories. This paper describes a simple method of measuring the thickness of sections actually used for stereological counting procedures. It involves the division of any given section into two portions, one of which is used for the counting procedures. The other portion is re-embedded and re-sectioned through its thickness making it a simple task to measure its thickness.