PATHOLOGICAL ANATOMY OF THE TESTICLE 481 



longest, and spermatogenesis ceases. Normally, potency should last until 

 the seventieth or eightieth year, sometimes longer. The interstitial cells 

 survive the spermatogenic elements, and therefore libido often outlasts 

 fecundity. In old testicles small scars are often seen, due to obliteration 

 of some of the tubules, and are said to occur more frequently in arterio- 

 sclerotics. 



Pressure. Atrophic changes from pressure in hydrocele, hernia, ele- 

 phantiasis, etc., do not occur or are extraordinarily slight. 



Postoperative. Following certain operative procedures, especially 

 those for hernia and varicocele, the testicle may undergo fibrous atrophy. 

 This is due to interference with the circulation of the testicle. 



Toxic. Degenerations occur as a result of toxic substances, such as 

 alcohol, lead, etc. The changes produced by alcohol are entirely micro- 

 scopic, and consist of thickening, hyaline degeneration, and narrowing 

 of the tubules, with a metaplasia of the epithelium to a cylindrical form, 

 and in advanced cases, cessation of spermatogenesis. The interstitial cells 

 survive. Extensive destruction of liver tissue causes alterations in the 

 testicle, apparently toxic in nature. 



Pigmentation. Pigments, like those found elsewhere in the body, 

 are deposited in the testicle in bronze diabetes. Senile testes contain a 

 brown pigment. 



Amyloid. Amyloid is found in the testicular vessels in amyloidosis. 



Gout. In very rare cases of gout, deposits of sodium biurate are 

 found in the testis. 



Infarction. Infarcts of the testicle are rare, but may occur as a 

 result of thrombosis or embolism. 



Gangrene. Gangrene of the testicle may occur as a result of trauma- 

 tism or of torsion of the spermatic cord. 



Infectious Diseases. Degenerations of the testicle occur in various 

 infectious diseases, but they are treated under inflammations, since a 

 meticulous distinction is impossible. 



Irradiation. When the testicle is subjected to prolonged action of 

 tf-rays, a degeneration of the spermatogenic elements occurs, commencing 

 with the least differentiated cells (spermatogonia) and involving later the 

 spermatids, spermatocytes, and spermatozoa. Therefore, cycles already 

 under way at the beginning of the exposure are completed, and sterility 

 appears slowly, but is eventually complete. The tubules are lined with 

 Sertoli cells and a few undifferentiated germ cells. Ordinarily, the inter- 

 stitial cells are not affected, but if the exposure is very prolonged, they too 

 may succumb, and the testicle undergo fibrous atrophy. If the exposure 

 has not been too long continued, its cessation is followed by a very slow 

 return of the spermatogenic function to normal. Kadium emanations are 

 also capable of causing sterility. 



