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11th Postgraduate Course for Training in Reproductive Medicine and Reproductive Biology Surgical treatment of male infertility George A. de Boccard SUMMARY Obstructive fertility problems can often be treated by surgery and the developpement of microsurgery has brought new posibilities to many infertile men. We will discuss the different surgical techniques to by-pass an obstruction, cure a varicocele and retrieve epididymal or testicular spermatozoa. KEY-WORDS Fertility - Vaso-vasostomy - Vaso-epididymostomy - Microsurgery - varicocele – laparoscopy - Testicular biopsy
INTRODUCTION Approximately 15% of couples are unable to conceive after one year of unprotected intercourse but a male factor is solely responsible in about 20% of infertile couples and contributory in another 30-40%. There are many possible causes of male infertility but only a few among them may be cured. Male infertility may occasionally be the manifestation of an underlying life threatening disease such as testicular cancer or pituitary tumor. The incidence of obstruction of the seminal excretory pathway in infertile men is estimated to be 7-14%(4) and ductal obstruction is responsible for 40% of cases. The advent of microsurgery opened a new era, giving hope to patients otherwise considered as definitely sterile. We will only discuss the surgically curable causes of infertility. Hormonal and infectious diseases will not be evocated. Only a few parts of the seminal tract can be reached by surgical procedures: intra-scrotal, subcutaneous or endoscopically at the level of the prostatic portion of the urethra. CONGENITAL PATHOLOGY OR AQUIRED OBSTRUCTION Parts of the seminal tract, especially the vas deferent, can be missing or obstructed, usually partially, sometimes totally. The cause can be congenital, associated with cystic fibrosis, post-infectious after genital tuberculosis, gonorrhoea or chlamydia, or iatrogenic after hernia repair, or the cure of an hydrocele. Vasectomy is also a major cause. If a short segment is missing or obstructed, it is possible to by-pass it. VARICOCELE Varicocele is commonly due to the absence of valves in one of the longest vein of the body, the left gonadic vein that drains in the left renal vein. It occurs in about 15% of the normal male population. It is found in 40% of those consulting for primary infertility and in up to 80% in men with secondary infertility. It is more often bilateral than earlier believed. Progressive atrophy and deterioration of testicular function is clearly associated with varicocele. Many authors relate the problem to an elevated scrotal temperature due to the lack of heath exchange at the level of the pampiniform plexus, others describe the toxic effects of elevated venous catecholamines, cortisol and renin(2). The presence of a varicocele is determined by physical examination but Doppler sonography must confirm the persistence of a retrograde flow during the Valsalva manoeuvre since only refluant varicoceles deserve surgery. There are two major indications for the treatment of varicocele: scrotal pain and infertility. A painful varicocele is generally large in size and easily diagnosed but the importance of subclinical varicoceles should be considered even in the presence of a small retrograde flow(5). If a fertility problem is mentioned, a refluant varicocele deserves a treatment anyway since the result of the cure is neither dependant upon the size of the veins nor upon the degree of the retrograde flow. However palpable varicoceles have a better surgical outcome. Young males with clinically palpable varicocèle should also be offered varicocele repair since progressive testicular atrophy is to be expected with future fertility problem. Surgical and non surgical techniques for the treatment of a varicocele are available:
The surgeon’s experience and skill, together with the options available, should determine the choice of varicocele treatment. Overall results of varicocele repair in collated studies show 50% to 90% improvement in semen quality and 30% to 50% may initiate a pregnancies after 6 to 9 months(7).For men with azoospermia or severe oligospermia, modest improvement in semen quality after varicocele repair may have a significant impact on a couples’ fertility options(18) EJACULATORY DUCT RESECTION In the prostate, after the junction with the seminal vesicle the vas ends in the ejaculatory duct at the level of the veru montanum. Even a small lesion in that region can cause an obstruction, often bilateral. Generally its etiology is inflammatory but in some cases a congenital malformation like a Mullerian duct cyst or a Wolffian malformation can be found. It is suspected in case of low semen volume (less than 1.0 ml) and absence of fructose in the seminal plasma. Perineal pain and hematospermia may be associated. The rest of the vas deferent is usually normal. Ejaculatory duct obstruction is best diagnosed by transrectal ultrasound echography. The treatment is performed endoscopically with a resectoscope incision along the veru montanum. Deep resection is sometimes needed and one must be very careful to avoid rectum perforation or sphincter lesion(5). In 25% of the cases we will see the return of living sperm. VASO-VASOSTOMY The most frequent cause of obstruction of the vas deferent is vasectomy. Among 100 men undergoing vasectomy, 2 will ask for a reversal. Short segmental agenesis, accidental section during hernia repair or post-infectious localised obstruction are more uncommon. The influence of the delay after vasectomy on the fertility rate is controversial because fertility rate decreases in any case naturally with time in normal men (15). Surgically, vaso-vasostomy can be performed anywhere along the scrotal and inguinal part of the vas. It is also theoretically possible intraperitonealy by laparoscopy but generally, as a consequence of vasectomy, it is done in the mid or upper part of the scrotum. We prefer the two-layers technique with the help of a microscope (stereoscopic f:300 lens). A 3 cm incision is made over the palpated upper end of the sectioned vas. The two ends are dissected from the surrounding tissues and exposed with the " Goldstein Microspike Approximator " if available, the scarred area are resected. The distal end is flushed with saline to check its permeability and dilate the lumen, fluid from the testicular end is checked for sperm by an extemporaneous microscopic examination. However absence of sperm cells is not conclusive for obstruction. The microspike approximator is installed and a yellow plastic drape is placed underneath in order to have a better view of the sutures. Then six 10-0 absorbable monofilament sutures are placed to approximate the mucosa, then the same number of 9-0 absorbable sutures are placed on the sero-muscular layer. Non absorbable sutures (i.e. Nylon) should be avoided since they may induce a macrophagic reaction Easy to perform is the modified two-layers technique which allows almost similar results: Four 9-0 monofilament absorbable sutures are placed at 6, 9, 3 and 12 O'clock through the serosa and the mucosa in order to approximate the two portions of the vas. Then four additional 9-0 sutures are placed on the serosa between the first four to ensure tightness of the vas. The use of a microscope is absolutely necessary in all cases In some vasectomy cases a large part of the vas has been resected, making tensionfree direct anastomose impossible. The epididymis can be dissected free from the testis, being attached only by the head and brought up to the distal end of the vas, thus making anastomosis possible without traction. Our own results show a 86% patency rate, comparable with the different published series. The pregnancy rate is over 60%. As stated before, the fertility rate decreases with time elapsed after vasectomy but the patency rate is still about 70% after more than 15 years of obstruction with a pregnancy rate of 49%. It should be noted that the mean time between vasectomy reversal and conception is more than twelve months and, more important, that the fertility rate of the reversal group is the same as in the normal control group(1). The age of the wife is essential : between 40 and 45 years, there are only 20% of pregnancies, over 45, there is no possibility. VASO-EPIDIDYMOSTOMY If obstruction is located at the level of the epididymis in the presence of a normal vas, the first choice therapy is vaso-epididymostomy. Also after an unsuccessful first vasectomy reversal attempt, and absence of sperm cells in the fluid, vaso-epididymostomy shall be performed. Anastomosis can be performed up to the efferent tubules on the testis After incision of the scrotum, the testis and the epididymis are exposed. The microscope is installed (stereoscopic f:300). The vas is dissected and his patency controlled by saline injection . The epididymis is freed from the testis, being only attached at the level of the head. It is then transsected at an apparently healthy level, leaving a bundle of open tubules apparent. After an initial general oozing of fluid, one of the tubule will permanently emit spermatic white fluid that shall be microscopically checked for spermatozoa. If none can be found at this level, a more proximal section will be performed. With the help of a specially designed vaso-epididymal microspike approximator the transsected distal vas will be brought to the opened tubule. If no sperm is found at this stage a testicular biopsy with cryoconservation is done in order to provide further fertilisation possibilities(11).We then perform an end to end anastomosis We first place four 10-0 absorbable sutures through the individual epididymal tubule and the mucosa of the vas; then the seromuscular layer of the vas is tightly secured to the tunica of the epididymis by eight to ten 9-0 absorbable sutures. Two 7-0 Nylon suture are finally externally placed to secure the external tunica of the vas to the epididymis, preventing any harmful traction. An older technique consists in opening laterally the epididymis proximally to the obstructed level and isolating a single tubule which is incised and not transsected, and anastomosed side to end with the same described technique. The results of this procedure show has a patency rate of 65 to 85% with a pregnancy rate of only 30 to 44%(12). Vasoepididymostomy has however a higher pregnancy rate than IVF with ICSI and should be preferred in any case of obstructive sterility at the epididymal level. It also allows a further second pregnancy without going through IVF procedure again. EPIDIDYMAL SPERM ASPIRATION Until recent years, no treatment was available in case of bilateral absence or bilateral total obstruction of the vas. The first description by Temple-Smith(11) of sperm micro-aspiration from the epididymis and in vitro fertilisation resulting in a pregnancy followed by Silber(9) who repeated the procedure with success opened a new field. Silber had even a better pregnancy rate in cases of agenesis than in those with acquired obstruction. The actual fecondation rate is 70% with 30% pregnancy rate(13). For the urologist, the technique is quite simple. The preparation of the epididymis is made as described for the second vaso-epididymostomy technique but instead of anastomosing the vas, the sperm coming out of the tubule is aspirated in a 2 ml insulin seringue( gamma sterilisation only) prefilled with Percoll. It is generally possible to collect 10 to 20 million spermatozoa within 30 to 60 minutes. The spermatozoa are exemporaneously examined, then frozen. The epididymal duct and the tunica of the epididymis should be closed as precisely as possible with 10-0 and 9-0 resorbable sutures, as well as the outer layers of the scrotum, to be able to repeat the procedure easily if required. The stimulation and the sampling of the oocytes from the partner will be indicated only in the presence of living spermatozoa, avoiding unnecessary procedures. I.C.S.I WITH TESTICULAR BIOPSY The development of the intra cytoplasmic sperm injection (I.C.S.I.) has opened a new field in treating sterile men. In fact, living spermatozoa can be retrieved in almost all cases of obstructive azoospermia. In other cases, even after a former negative biopsy and elevated FSH, it is still possible to retrieve living spermatozoa in about 50% of cases. Biopsy is best performed by exteriorizating both testis and obtaining one or more fragments which should be extemporaneously examined in order to find a producing zone in the testis(18). Percutaneous biopsy, although described, doesn’t give as good results. The biopsy, if containing a complete spermatogenetic process, even in patients with tubular atrophy, will allow the biologist to pick up one single spermatozoa and inject it in the oocyte. This procedure has a comparable or even higher fertilisation and pregnancy rate than IVF alone (13,14,16).Cryopreservation of the sperm allows to delay female stimulation, avoiding unnecessary expensive treatments MICROSURGICAL REPAIR VERSUS SPERM RETRIEVAL Vasovasostomy and vasoepididymostomy have been demonstrated as more cost-effective than sperm retrieval with FIV or ICSI. Also, successful reconstruction allows couples to have a second child without additional medical procedure. Therefore, microsurgical reconstruction is best indicated as an initial treatment for obstructive azoospermia REFERENCES
Edited by Aldo Campana, |