BIOMECHANICAL PROPERTIES OF NORMAL AND VARICOSE INTERNAL SPERMATIC VEINS

To investigate possible differences in biomechanical properties betwee n varicose spermatic veins and controls. During surgery on 12 patients for grade 3 left-sided varicocele testis, 2 cm of the vein was obtain ed for comparison with: (i) samples of the left internal spermatic vei n taken from the same anatomical localization from 8 patients without scrotal disease, and (ii) samples from the right internal spermatic ve in from 7 other patients also without scrotal disease. The biomechanic al properties of ring shaped venous specimens were investigated by loa ding the specimen at a constant deformation rate until rupture. The re lative amounts of collagen in the specimens were determined as the con tents of hydroxyproline. There was a significant difference between va ricocele testis/right spermatic vein in UC (unit collagen), F-max (max imum strength), Strain (ultimate extensibility) and E-fail (relative f ailure energy), but not in LD (diameter) and Tan-a (stiffness of the s pecimen). There were no significant differences between left and right spermatic vein in LD, UC, F-max, Strain, Tan-a and E-fail. There was a significant difference in LD between varicocele testis/left spermati c vein, but no relationship in UC, F-max, Strain, Tan-a and E-fail. Bi omechanical analyses of the spermatic veins from patients operated for varicocele seem to support the hypothesis that a difference in biomec hanical properties plays a part in the development of varicocele becau se a significant increase in extensibility of varicocele samples was f ound compared with normal right spermatic vein samples.