Necrosis may occur suddenly when the infecting organism is specially virulent, and may affect one-third, one-half, or the whole of the gland. The prognosis then becomes extremely grave, and if diagnosis has not been prompt and treatment energetic, death may follow in a short time from septic infection.
Treatment. Unless some well-marked sign foreshadows a complication, treatment should be directed to ensuring resolution. Bleeding has been recommended; its good effects, however, are open to doubt, though one cannot entirely forbid it. All practitioners agree in recognising the value of vesicant applications. The affected parts may be freely dressed with an ointment containing 2 per cent. each of pulverised tartar emetic and bichromate of potash, with the ordinary cantharides blister, or even with a weak mercurial blister, provided that the animals can be prevented from licking the wound.
Some practitioners prefer vesicants prepared with cantharides and croton oil. Whatever be the vesicant chosen, it is best after three or four days to apply emollients of slightly antiseptic character, such as ointments containing camphor, boric acid, salol, etc. When abscess formation is recognised the abscess should be opened as early as possible. Some precautions are necessary to avoid injuring important nerves and vessels; in dealing with a deep-seated abscess it is necessary to use the knife for dividing the skin alone, to seek the abscess by blunt dissection with the finger or with round-pointed scissors, and to open it with a similar instrument. The cavity should then be freely washed out with a warm antiseptic solution—3 per cent. carbolic solution, or 1 per cent. iodine solution, etc. If necessary a drain composed of iodoform gauze can be inserted, or a counter-opening made.
In the case of partial necrosis, all the necrotic tissue must be carefully removed, injury to vessels, which would favour septicæmic infection, being avoided. Afterwards free antiseptic irrigation should be employed several times per day.
In necrosis of the entire parotid extirpation may seem indicated; but the greatest prudence is demanded, for the operation is extremely serious and delicate.
CHRONIC PAROTIDITIS—PAROTID FISTULA.
When a case of acute parotiditis is not treated, and does not end in suppuration, it is usually succeeded by chronic inflammation and fibrous induration of the gland. Any obstruction of Stenon’s duct, whatever the originating cause (foreign bodies like wheat awns, oat grains, calculi, etc.) stops the flow of saliva throughout the excretory apparatus, and produces over the entire parotid region a doughy swelling, which might seem to indicate the existence of indolent parotiditis. The collections of liquid thus produced have improperly been termed “salivary abscesses.” If ascending infection fails to occur, or if infection is unimportant and does not lead to suppuration, a relatively painless chronic parotiditis develops, and in this case movements of the head and mastication and deglutition alone are impeded.
The salivary ducts, however, may become so distended that the main superficial collecting duct undergoes softening, and the skin covering it becomes ulcerated, just as would occur had a true abscess formed. Under such circumstances the skin soon yields and a salivary fistula is established.
The symptoms consist in swelling or induration of the gland, interference with movement of the head and with mastication; the whole developing slowly without pain or fever.
The distinction of this condition from actinomycosis of the parotid may sometimes present some difficulty until a fistula develops.