Testicular torsion: simple grading for histological evaluation of tissue damage.

Histological investigation of 63 biopsies taken during surgical detorsion of twisted testes reveals 3 morphologically different degrees of damage. In grade 1 injury the testicular parenchyma shows edema of interstice, slight blood extravasation and a desquamation of the germ cells. The grade 2 injury is characterized by a diffuse hemorrhagic saturation of the interstice and partial necrosis of germ cells. The grade 3 injury corresponds to a fully developed hemorrhagic infarction of the testis. The biopsies taken within the first 4 h after onset of symptoms show a relatively high number of minor changes (grade 1) which hold out hope for restitutio ad integrum. Grade 2 injury predominates in the period between 4 and 8 h, but it can appear also in the first 4 h. Only after 24 h all the testes examined are completely necrotic. This study shows that the amount of time that elapses between onset of symptoms and surgical detorsion is not the only factor to predict the outcome of the injured testis.