Study of relationship between volume of vas and the vas anatomy

Objectives: To Study the relationship between volume and anatomy of vas deferens. Design: Experimental studies on human vas deferens. Settings: Family planning clinics in Sichuan Province and laboratories in Sichuan Reproductive Health Institute. Subjects: 210 fresh vas samples from 107 volunteers of vasectomy. Method: The inner and outer equivalent diameters of vas deferens were measured by using computerized image graphic analysis technique with microphotography. The maximal volume of 1 cm vas deferens was determined by injection of colored solution. The histological observation of vas deferens rupture was conducted with continuous sections. Result: The average outer and inner diameters were 2.17±0.20 mm and 0.56±0.08 mm,respectively. The calculated thickness of vas wall was 0.81±0.21 mm.The average vas lumen volume vas lumen of was 0.05± 0.007ml.Different urpture manners of vas wall were found in histological observation. There is no significant relationship between the maximized vas volume and the anatomic parameters or physiologic characteristics,except the thickness of vas wall and the personal height. Conclusion:This study provides objective anatomic data about Chinese human vas deferens, and the maximal limit of vas volume in the 1 cm vas deferens. The diameter of vas deferens is not a suitable indicator for determination of injection volume in vas occlusion because only the thickness of the wall relates significantly to the vas volume.