Quantitative parameters for light microscopic assessment of the tubuli seminiferi.

For quantitative, histologic assessment of the testis tubuli there are four suitable parameters: diameter of tubulus, area of tubulus, number of cell nuclei per tubulus, and area of nuclei of the various cells participating in spermatogenesis. For estimating areas, the integrative method of measurement, either with a grid or with the aid of the manual optical picture-analysis system, is proposed. The tubulus diameter can be determined rapidly and easily, although the tubulus size can be assessed more accurately by area estimation. An assessment of reproductive capacity in detail is possible by means of rather time-consuming determination of cell nucleus number and nuclear area, whereby the stages of the cycle of the seminiferous epithelium must be considered.