370 PRINCIPLES OF VETJERINARY SURGERY 



The prognosis is always grave. Large animals may exhibit 

 indelible blemishes after recovery, and the dog and cat have 

 often to be destroyed on account of the expense entailed by 

 protracted treatment. 



PATHOLOGICAL ANATOMY.— In the environs of 

 an ulcer the horny layer of the epidermis thickens while the 

 deep layers become weaker; the papillae of the skin become 

 enlarged and the blood-vessels increase in diameter. The 

 skin becomes sclerotic and the ulcer itself is constituted of 

 embryonic tissue resting upon a dense fibrous bed. 



Ulceration is essentially characterized by the phenom- 

 enon of molecular necrosis accompanied with an inflamma- 

 tory reaction. The adult elements of the tissues are replaced 

 by embryonic elements, but the inflammation which is re- 

 sponsible for these transformations is not a typical one; it 

 is always spurious and incapable of repairing the lesion. The 

 newly-formed elements, being subjected to the same de- 

 pressing influences as the pre-existing elements, degenerate 

 and retrograde, before reaching a state of complete develop- 

 ment. The phenomenon of mortification usually prevails 

 over the process of repair. There is a conflict between two 

 absolutely different states, and as one or the other predomi- 

 nates, the ulcer either becomes larger or is transformed into 

 a benign sore. 



TREATMENT. — The treatment must vary according to 

 the nature of the ulcer. When it is atonic, essence of turpen- 

 tine, or cauterization with silver nitrate is the most fre- 

 quent recourse. If, on the contrary, it is fibrous and lardace- 

 ous, the thermo-cautery lightly applied has the most success- 

 ful efifect. Proud flesh, exuberant and colorless, which has 

 no tendency to organize, should be destroyed with perman- 

 ganate of potash, copper sulphate, or chromic acid. Painful 

 ulcers may be treated with hot antiseptic baths and soothing 

 ointments, and those having a tendency to trangress on- 



