The Abdomen 221 



casionally occur, while instances of primary and secondary carcino- 

 mata and sarcomata have been recorded. 



Hydronephrosis. This term is applied to the accumulation of 

 aseptic matter within the kidney. The lesion originates from ob- 

 struction of any part of the urinary tract, and may be partial or com- 

 plete, and according to the position of the obstruction, may be uni- 

 lateral or bilateral. The condition is described more fully in the 

 chapter on Neoplasms. It will suffice here to point out that when 

 the onflow of the urinary secretion is arrested, glandular secretion 

 continues for a time and the kidney, together with the portion of the 

 ureter above the obstruction becomes enormously distended. The 

 intraglandular pressure thus produced causes atrophy of the secret- 

 ing elements, and finally, if the condition continues long enough, 

 nothing remains of the erstwhile kidney but a large fibrous sac 

 with cystic contents. 



Unilateral hydronephrosis is not necessarily dangerous, the 

 opposite kidney taking on the function of its degenerate fellow 

 (compensatory hypertrophy). Bilateral hydronephrosis is neces- 

 sarily fatal, the rapidity of the approach of dissolution depending 

 upon the degree of obstruction to the urinary flow. In one in- 

 stance experimentally produced by myself, but in which complete 

 occlusion of one of the canals had not taken place, the animal 

 lingered three weeks, all the while gradually becoming weaker and 

 narcosed from accumulation in the blood of non-eliminated poisons. 



Symptoms and Diagnosis. In unilateral hydronephrosis, symp- 

 toms may be wanting and micturition still taking place. Life may 

 continue indefinitely, the healthy kidney taking on the function of 

 its fellow. In the bilateral form, micturition is gradually sup- 

 pressed, the animal at the same time exhibiting progressive emaci- 

 ation, anorexia, and pronounced lethargy. Abdominal palpation re- 

 veals the presence of an elastic tumor. Explorative celiotomy should 

 then be undertaken. The abdominal cavity being opened, the 

 tumor is seen intimately adherent to the sublumbar wall, and its 

 base traversed by well-developed blood vessels. The cyst fluctu- 

 ates. 



Treatment. If the degenerative process has not involved the 

 entire kidney and the urinary tract can be made patent again, the 

 gland should be left undisturbed. But if the glandular tissue is 

 hopelessly involved, the only practicable alternative is to perform 



