In a vasectomy the sperm duct between the testicle and the seminal vescicle (the vas deferens) on each side is cut. A vasovasostomy attempts to repair both cut vas deferens and allow sperm to again pass from the testicles.
Under general anaesthetic the cut ends of the vas deferens are exposed through incisions on each side of the scrotum. Under a microscope, these very small tubes are carefully cleaned and freshened by recutting a tiny portion of the tube end. A discharge of semen from the end closest to the testicle is a good sign. Extremely small sutures are used to meticulously join the cut ends of the vas deferens together again and ensure a good blood supply. Every effort is made to ensure that the tube remains open at the join, as it is easy for scar tissue to form and block the tube at this point.
Sex should be avoided for at least six weeks after the operation of a vasovasostomy, and the bruised scrotum should be well supported. The sperm is usually analysed from an ejaculate about two months after the procedure, and regularly after that until a good result is obtained. If good quality sperm are not present after 18 months, the operation has failed and a further revision operation or the use of a sperm extraction technique may be considered.
The outcome depends on:-
- the length of time since the original vasectomy (the longer the time, the worse the outcome)
- the procedure originally used for the vasectomy (cutting out a length of vas deferens and diathermy of the tube ends give a poorer outcome)
- the experience of the surgeon (the more experience the better)
- the presence of clear fluid at the testicular cut end of the vas deferens (a thick fluid or no discharge indicate a poor prognosis)