Prediction of the extent of germ cell loss utilising a noninvasive spectroscopy method in rat testicular damage model

The aim of this study is to investigate the efficiency of elastic light single‐scattering spectroscopy system, a noninvasive method, to acquire spectra during testicular biopsy from normal and damaged seminiferous tubules with various degrees of germ cell loss. Adult control rats and doxorubicin‐injected rats to achieve seminiferous germ cell loss (for 10 days [10D], 20 days [D20], 30 days [D30], 40 days [D40], and 50 days [D50]) were used. Spectroscopic measurements were acquired utilising a single‐fibre optical probe, and histopathology of the biopsied testicular tissue samples were compared. Time‐dependent testicular damage comprising various degrees of seminiferous tubule degeneration after doxorubicin‐administration was observed. In D30, D40 and D50 groups, where significant germ cell loss was identified, elastic light single‐scattering spectroscopy system signals were well correlated with disturbed spermatogenesis where significant differences in spectral signals were obtained. Our findings indicate that the elastic light single‐scattering spectroscopy system has the potential to enable instant imaging of spermatogenesis in rats and could also be useful in humans for clinical applications, such as to increase sperm recovery success during micro‐TESE for men with nonobstructive azoospermia.