Higher incidence of sperm granuloma in the epididymis of C57BL/6N mice / 한국실험동물학회지

C57BL/6N mice are inbred strains widely used in biomedical research. Hence, a large amount of basic data has been accumulated. However, in the field of histopathology, spontaneous data for relatively younger mice that are used more frequently are not yet abundant, in contrast to data for older mice and their neoplastic lesions. To acquire the essential background data required by various research and toxicological assessments, 120 mice of the C57BL/6N strain (10 and 13 weeks of age) were collected from two institutions (From Korea and Japan) and subjected to histopathological analyses of the major organs (liver, spleen, kidney, thymus, heart, testis, epididymis). The results showed significantly higher incidence of sperm granulomas in the epididymides (10-56%) of these mice, compared with that in other strains or species of lab animals. Upon closer inspection, oligospermia/clear cell hyperplasia, cellular debris, and tubular vacuolation were also observed in the epididymides with sperm granulomas. Moreover, diseased organs were significantly heavier than healthy ones. Immunohistochemical staining showed a significant increase in the chromatic figures of cysteine-dependent aspartate-directed proteases-3 (caspase-3) and cleaved-poly(ADP-ribose) polymerase (c-PARP), and damages to the tubule due to spontaneous apoptosis, which may have led to the sperms leaking out of the tubule, causing the granuloma. To conclude, spontaneous sperm granuloma can occur in 10- and 13-week-old C57BL/6N mice and may thus affect the results of various studies using these mice. Therefore, sperm granuloma in epididymis needs to be carefully considered as an important factor when design the study using C57BL/6N.

Morphometric study of the testis and reproductive tract (including sperm granuloma) after vasectomy in mature rats / 亚洲男科学杂志(英文版)

By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated: the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy: double ligation (without severing) of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia (juxta-epididymal segments), and sperm granulomas (at the vasectomy site) were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase (by 111% on average) in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase (by 66%) in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.

Sperm Granuloma and Success Rate of Vasovasostomy / 대한비뇨기과학회지

A discrepancy between patency and pregnancy rates persists even if a surgical success rate of vasovasostomy, improved. A sperm granuloma has been considered that it has relation to improvement of quality of sperm by decompression of intravasal pressure. During the period from 1981 to 1983, a total of 160 vasovasostomies were performed. An age of the patient ranged from 24 to 65 with the mean of 36.5. Duration of obstruction ranged from 5 months to 20 years with the mean of 4.2 years. Viable sperms more than 10 x 1,000,000/ml appeared in 145 out of the 160 patients (90.6%) , and pregnancy occurred in 98 out of the 160 patients (61.2%) following the vasovasostomy The sperm granuloma was found in 50% of 160 vasectomized patients. Forty-eight percent of patients whose patency were restored had sperm granuloma. Fifty percent of patients who impregnated their wives had sperm granuloma. There was statistically no significant difference in both patency and pregnancy rates between patients with and without sperm granuloma. But sperm months at 6 months post operatively was found to be higher in patients with sperm granuloma than without sperm granuloma (p<0.05).

Clinical Observation on Sperm Granulomas after Vasectomy / 대한비뇨기과학회지

The fifteen specimens of fibrous tissue resected from the previous vasectomized site on 15 cases were studied histopathologically and the following results were obtained. 1. Sperm granuloma was observed in 9 cases out of the 15 cases (60%). 2. Foreign body granuloma with suture material was observed in 8 cases (53%). 3. Six cases (75%) of sperm granuloma were observed in 8 cases having the foreign body granuloma with the suture material, where as 3 cases (43%) of sperm granuloma were observed in 7 cases not having the foreign body granuloma. 4. Sperm granulomas and suture granulomas were combined in 6 cases (40%) out of the 15 cases. 5. One case of spontaneous recanalization following vasectomy resulted from the sperm granuloma. 6. Pathogenesis and preventive measures of sperm granuloma were discussed here.

A Patho-histologic Study on Experimental Sperm Granuloma / 대한비뇨기과학회지

As Glassy and Mostofi stated, sperm granuloma is not rarely encountered in clinical practice and more cases are expected to occur due to practical vasectomy for family planning. Incomplete ligation after vasectomy or increased intraluminal pressures of vas deferens after vasectomy seems to predispose sperm granuloma. However, it is hard to review in literature to understand on its exact etiological mechanism and histologic picture of the lesion. The author has selected male albino rats and divided into 3 groups. Group I only ligation of the vas, group 2 vasectomy and ligation and group 3 vasectomy only without ligation. Gross and microscopic findings after 4 weeks were as following; 1. Pathologic lesions were noted in each experiment group. 2. Pathologic lesions were more frequently noted in group 2 and 3 than group 1. 3. The size of the pathologic lesion was larger in group 3 than group 1 or 2. 4. Pathologic lesion in group 1 or 2 was due to distention of the lumen due to increased intraluminal pressure and that of group 3 was due to leakage of the sperm into the surrounding soft tissue. 5. Pathologic lesions noted in this experiment was similar to those of human sperm granuloma.