Comparison of blood flow and histological changes in rat models of testicular ischemia.

Purpose: Our aim was to quantify objectively the degree of vascular insufficiency produced by twisting versus clamping the spermatic cord, and determine the contribution of the vasal vessels to these changes using the laser Doppler flowmeter.

Materials And Methods: Three groups of 12 male Sprague-Dawley rats each were studied. Group 1 underwent 720-degree torsion of the spermatic cord, group 2 underwent vascular clamping of the spermatic cord with 1 clamp, excluding the anatomically separate vasal vessels, and group 3 underwent vascular clamping of the entire spermatic cord and vasal vessels with 2 clamps. Blood flow and histological changes were determined.

Results: Vascular clamping of the spermatic cord in groups 2 and 3 resulted in a significant decrease in testicular blood flow compared to 720-degree torsion (p < 0.05). These flow changes correlated with more severe and reproducible gross changes, and histological features of seminiferous tubule degeneration compared to spermatic cord twisting.

Conclusions: In the rat clamping the spermatic cord is a more severe and reproducible model of testicular torsion than 720-degree torsion. The contribution of the vasal vessels to the decrease in blood flow and resulting histological degeneration after testicular ischemia is negligible in the rat.