The vas deferens is a relatively large pipe, but the its lumen--the actual tube that carries the sperm--is very small. The goal of a vas reversal is to re-connect that tiny tube and ensure that it remains open, or patent,as we say in medical jargon. Here are some factors that influence success.
1: Obstructive interval--this refers to how much time has passed, in years, since the vasectomy was performed. In general, the shorter the better, but success rates for vas reversals performed up to 9 years after the initial vasectomy still reach into the 90% range, for skilled surgeons. Patency rates tend to dip a bit after the 9 year mark, but remain high, ~70%. Vas reversals have successfully been performed on men with 20 years long obstructive intervals!
2: Vasal fluid inspection: During the vas reversal, after identifying the were the vasectomy was performed, the surgeon opens the vas deferens and examines the fluid that leaks from the open tube. The fluid is inspected for a number of factors, and whether or not the fluid contains sperm is the most important prognostic indicator that the vas reversal will be successful.
3: The location of the anastomosis--when the surgeons re-connect the 2 ends of the vas, that connection is called the anastomosis. Anastomoses performed at the level of the vas have higher patency rates than when the vas is connected to a site closer to the testicle, such as the epididymis, the tube that sits on top if the testicle.
4: Technique: The microsurgical approach using very fine suture material and adherence to strict surgical technique will give the best results. The anastomosis must be perfectly water tight and under no tension or the anastomosis is sure to eventually fail.
As always, any questions, please feel free to contact me.
