30 Surgical Diseases and Surgery of the Dog 



They must be opened, irrigated, thoroughly curetted, irrigated 

 again, and packed with antiseptic gauze. 



ULCER. 



An ulcer is an open sore of a superficial structure. It is brought 

 about by ordinary pyogenic or specific bacteria acting the same as in 

 abscess, an ulcer being a molecular death of a part of a free surface, 

 an abscess the same thing within the tissues, pus being secreted in 

 either case. But before such pyogenic bacteria can exert any ill- 

 effect in a tissue, there must be some impairment of vitality of the 

 latter either through destruction of its integrity by local irritation, 

 mechanical violence, etc., or interference with its nutrition owing to 

 disturbance of the local circulation or malnutrition of the body in- 

 duced by disease. Ulceration may be regarded as an inflammatory 

 disturbance which has continued past the point where healing takes 

 place by granulation, or a sort of continued local dying of a part, 

 though it is quite possible for an ulcer to heal spontaneously. A 

 wound that does not heal by primary intention or scabbing becomes 

 an ulcer. The process of ulceration consists of an infiltration of the 

 inflamed area with leucocytes which destroy and replace the tissues. 

 The leucocytes dying they are thrown off with the fluid elements de- 

 rived from the blood as pus. 



Common seats of simple ulceration are the edges of the ear- 

 flaps, the external auditory canal, the tail, and the digits. Of specific 

 origin are tubercular ulcers particularly of the neck and the ulcers 

 of stomatitis. 



Symptoms and Diagnosis. As already stated, any sore or 

 wound which does not heal by granulation is to be regarded as an 

 ulcer. But the process of ulceration may be healthy, or it may be 

 indolent, or exuberant. In a healthy ulcer the edges are smooth, 

 the base level and covered with healthy granulations, the surround- 

 ing parts normal, and an inodorous pus is discharged. An indo- 

 lent ulcer is known by its sunken surface, its raised irregular edges. 

 The discharge may be thin and watery. An exuberant ulcer is 

 characterized by development of so-called "proud flesh," gelatinous 

 granulations rising above the level of the surrounding parts. It is 

 dark red and bleeds freely and discharges pus. 



Treatment. In the treatment of ulcer it is important to protect 



