Establishment of a rabbit model of different degrees of testicular torsion.

Introduction And Objectives: Different degrees of testicular torsion result in varying degrees of testicular damage, which influences treatment options and outcomes. Therefore, establishing a testicular torsion model with different degrees is necessary for clinical diagnosis.

Materials And Methods: Rabbits were randomly divided into four groups and their spermatic cords were twisted at 0 °, 180 °, 360 °, and 720 °, respectively. Color Doppler flow imaging (CDFI) were performed to evaluate the blood supply in testicles. The twisted testicles were surgically removed at six hours post-operation and were evaluated by morphological observation and Hematoxylin and Eosin staining.

Results: CDFI signals were gradually decreased as the degree of testicular torsion increased, and scores of CDFI in the 360 ° and 720 ° groups were significantly decreased at postoperative six hours compared to pre-surgery. Compared to the sham, the testicle in the 180 ° group exhibited slight congestion, whereas the testicles in the 360 ° and 720 ° groups were dark red in color and had severe congestion and unrecognizable vessels. Hematoxylin and Eosin staining showed mild spermatogenic cell reduction and testicular interstitial hemorrhage in the 180 ° group. In the 360 ° and 720 ° groups, disordered seminiferous tubules, shed spermatogenic cells in tubules, inflammatory cell infiltration, and severe hemorrhage were found. In comparison with the sham, interstitial hemorrhage scores in the 360 ° and 720 ° groups were significantly higher, and scores of germinal epithelial cell thickness in the three testicular torsion groups were significantly decreased.

Conclusions: Collectively, we successfully constructed a testicular torsion model with different degrees in rabbits.