Congenital absence of the vas deferens.

Fourteen personal cases of agenesia of the vas deferens, bilateral in 12 and unilateral in 2, are described. In 13 of the cases the diagnosis was confirmed by surgical exploration. In most of the cases cytologic examination of aspiration biopsy specimens and histologic examination of surgical specimens of the testes showed that spermatogenesis was normal. The appearance of biopsy specimens of the epididymides were normal except for a certain degree of interstitital fibrosis and dilation of the ductus epididymidis. Endeavours to produce an artificial spermatocele with the aid of an isolated flap of tunica vaginalis in several patients proved unsuccessful. In one patient with a naturally preformed spermatocele the latter was aspirated, and the patient's wife was inseminated with the cellular content from the aspirate. This procedure has been repeated on several occasions, but so far without any subsequent conception. The failure of treatment of these patients may perhaps be due to some change in the function of their epididymides. This possibility is discussed.     

Cutaneous fistulas to the vas deferens.

Cutaneous fistulas to the vas deferens are a rare occurrence. A careful review of the literature revealed only 16 cases reported within the last 70 years. We present a case of such a fistula occurring after inguinal orchiectomy for suppurative epididymo-orchitis and review the etiologies of all reported cases to provide recommendations for management.     

Ectopia of the vas deferens

Ectopic location of the vas deferens is a rare congenital abnormality that has a spectrum of presentations. Such cases have been associated with anorectal anomalies. Knowledge of distal Wolffian duct embryology may help to explain the developmental steps involved in these anomalies, as well as provide theories for the variations that may be encountered. Vas deferens development is reviewed, and two cases of vas ectopia are presented to illustrate and lend support to current theories of normal and abnormal vasal embryology.     

Physiology of the vas deferens

Summary Seminal emission occurs in response to rhythmic contractions of male secondary sex organs, including the vas deferens. Although contraction of the vas is directly due to adrenergic mechanisms, numerous substances modulate the release of norepinephrine from sympathetic pathways. These substances include local endogenous factors and neurotransmitters such as acetylcholine and NPY. Many substances are capable of altering the contractility of the vas deferens by modulating neural transmitter release or the basal tone of this smooth muscle. Because multiple pathways and substrates are capable of affecting its contractility, it is not surprising that drugs and metabolic disorders influence the function of the vas deferens and, ultimately, male fertility.     

Histopathological alterations of the vas deferens in rats exposed to polypropylene mesh

OBJECTIVE: To assess the histological and physiological effects of polypropylene mesh for inguinal herniorraphy, as it can cause lesions in the vas deferens in 0.3-2.0%, leading to infertility, and induces an inflammatory process and adjacent fibrosis, strengthening the posterior inguinal wall. MATERIALS AND METHODS: In all, 40 male albino rats (3 months old) had bilateral vas deferens dissection followed by mesh implantation on one side; the contralateral side was used as the control. The rats were killed 90 (group 1) and 120 (group 2) days later, and the vas deferens, epididymides and testicles assessed histopathologically. RESULTS: There was a foreign-body reaction after mesh implantation, but not in the controls. The mean lumen dilatation in regions proximal to the mesh in groups 1 and 2 was 0.468 and 0.371 mm(2), respectively, and all the sections had spermatozoids. The mean dilatation in control groups 1 and 2 was 0.239 and 0.170 mm(2), respectively, with spermatozoids present in 58% and 75%, respectively (significant, P < 0.05). In group 1 the wall thickness of mesh-implanted segments reduced to 0.177 mm, and in segments proximal to the mesh to 0.099 mm; the control segment was 0.298 mm (P < 0.05). In group 2 the mean thickness of mesh-implanted and proximal segments was 0.134 and 0.224 mm, respectively, while in the control it was 0.284 mm (not significant). There was loss of mucosal folding in all segments proximal to the mesh but not in the control. The epididymides and testicles were unchanged. CONCLUSION: Polypropylene mesh induces a foreign-body reaction, with histological changes in the vas deferens that cause functional obstruction, with dilatation and spermatozoid repression.     

Reconstruction of vas deferens

If the vas deferens repair operation is done in properly selected pa tients, it is possible to achieve success in 50% of cases. The method o f reconstruction used by the author is outlined and technical difficulti es are indicated. The longer the time interval between vasectomy and the repair operation, the less the chances of success. Where the interval is more than 5 years, a preliminary testicular biopsy is advised. It is better to limit the operation to patients below the age of 45 years. Care must be taken to avoid injury to blood vessels. End- to-end union of cut ends without tension must be made over an indwelling splint. The splint is removed after 6 days. When sufficient length of the vas is not available for repair without tension, a mobilization of the vas may be done similar to what is done in cases of undescended testicle. When the distal end of the vas is too short or stenosed, a vasoepididymal anastomosis may be possible. Placing a splint in these cases has been advocated also. It is better to do the operation on 1 side only. If spermatozoa are absent after 3 months, the other side may then be operated on.     

Agenesis or atrophy of the testis and vas deferens.

In this study the author examines the relationship between agenesis or atrophy of the testis and of the vas deferens. From a prospective study of 237 cases of unilateral and bilateral undescended testis, 12 cases of agenesis of a testis were seen; 9 of the 12 cases were associated with agenesis of the vas deferens and in 3 of these unilateral renal agenesis was also present, not necessarily ipsilaterally. Three other cases of testicular agenesis and four cases of extreme testicular atrophy were seen. In all seven, the vas deferens was present in part or in its entirety and roentgenography disclosed a normal upper urinary tract. Agenesis of the vas deferens was seen only in patients with monorchism. No patient was anorchid. It is concluded that an important link exists between agenesis of the vas deferens and agenesis of the testis.     

Differences in the physiological response and ultrastructure of human and guinea pig vas deferens. Effects of prostaglandins, irradiation, and temperature

Marked differences were observed in the mechanical reactions of human and guinea pig vas deferens to prostaglandins, irradiation, and cooling. In human preparations prostaglandin E1 (0.1-1 ng/ml) had an augmentory effect on the contractile response after electrical neurostimulation (10 Hz, 0.3 ms, 3 s), but no visible influence (at concentrations ranging from 1 ng to 10 micrograms/ml) on the contractile response after electrical muscle stimulation (10 Hz, 40 ms, 3 s). In contrast, in guinea pig preparations (PGE1 (0.1-1 ng/ml) had an inhibitory effect on the contractile response after electrical neurostimulation and an augmentory effect (0.1-1 micrograms/ml) on the contractile response after electrical muscular stimulation. Human vas deferens showed higher radiosensitivity than guinea pig preparations. The neurotransmitters acetylcholine and catecholamines increased the radiosensitivity of guinea pig preparations, but not of human ones. Vas deferens reacted to short-time (15-120 s) cooling with an immediate temporary contraction, at 25 degrees C of short (seconds), at 5 degrees C of long (minutes) duration; after rewarming (5-37 degrees C) a second contraction appeared in guinea pig preparations, but not in human ones. Whereas the contraction to electrical neurostimulation (10 Hz, 0.3 ms, 3 s) was abolished in human preparations by cooling, it was only inhibited in guinea pig vas deferens. Electron microscopy showed differences in the ultrastructure of human and guinea pig vas deferens. Muscle cells were more widely separated in human vas deferens (generally 400 nm or more) than in guinea pig (approximately 100-200 nm), and the intracellular space in human preparations contained more collagen. The axons in human preparations contained predominantly large granular and agranular vesicles, those in guinea pig preparations small granular and agranular vesicles. The possible correlation between the physiological response of human and guinea pig vas deferens and the ultrastructural differences is discussed. The results indicate the possibility that other pharmacophysiological and toxicological phenomena could be essentially different in human and guinea pig material.