One third of infertilities is of exclusive male origin and one third of mixed origin (presence of a male factor). Ten percent of infertile male have azoospermia with a secretory origin in most of cases. Surgical extraction of spermatozoa from testicle is the unique possibility to increase the chance for these men to have children using in vitro fecundation. However, surgical extraction of spermatozoa is successful in 50% of these patients. To date, none of the methods for exploration of male fertility (spermogram, hormonal investigation - with dosage of FSH (follicle stimulating hormone) and inhibin B - and scrotal ultrasound) can predict the success of surgical sperm cells extraction. We also miss the prognostic markers of the testicular function recovery after sterilizing treatments (chemotherapy, radiotherapy). The presence of GLUT3 (glucose) transporters, which are responsible for the fluoro deoxyglucose uptake, has been reported in seminiferous tubules. We have previously shown in a pilot study on a population of men without testis cancer that FDG PET-CT parameters - including the standardized uptake value mean, the standardized uptake value max, and the functional testicular volume - were correlated with the parameters of spermogram (sperm count, motility, vitality). These findings open the way to investigations on the role of the FDG PET-CT in evaluation of secretory azoospermia.