IXFLAMMATIOX OF THE EXTERNAL EAR 



435 



foreign l:)odies; also too frequent bathing with soajD is a common canse of 

 irritation. Sporting dogs, such as spaniels, setters and retrievers and 

 Chesapeake Bay dogs, from going into icy cold water. It may accompany 

 or follow distemper, or by extension of inflammatory processes from the 

 surrounding tissues, such as injuries, bites, etc. It is also recognized 

 that otitis is produced by acari. (See Parasitic Otitis, page 439). Hoff- 

 mann states that he has observed serious suppuration in cases where 

 dogs' ears have been clipped too close to the head. 



Clinical Symptoms and Prognosis. — Great care must be used in 

 making the first examination of the ear to distinguish between superficial 

 and deep external otitis. In the former form it may rapidly become 

 chronic. The animals shake their heads, and, as the disease is almost 

 invariably located in one ear only, they hold their head in an oblic{ue 

 position, trying to scratch the head about the base of the ear or to rub 

 it against some object. They carefully avoid any attempt which is 

 made to touch the ear, and show great pain when the base 

 of the concha is touched. Milder cases rather encourage 

 manipulation of the ear and if the ear is gently rubbed they 

 show every sign of pleasure. In examining the external ear 

 we use a forceps-shaped speculum or ear-mirror (Fig. 156). 

 If we distend the canal we generally find it filled with a 

 foetid, grayish-green, or reddish liquid consisting of gland- 

 ular secretions, fungi, cutaneous scabs, pus, acari, etc. 

 After the organ is cleaned out we find an intensely red, 

 swollen, sometimes ulcerating surface of the skin. In the 

 deep-seated cases the meatus is almost entirely closed by 

 thickening of the cutis and an abundant purulent dis- 

 charge from the ear (otorrhcea). Numerous granulations 

 appear cjuickly and in some cases where both ears are 

 affected we may have symptoms of impaired hearing or 

 deafness. A characteristic smacking or sucking liciuicl 

 sound is produced by side pressure or rapid compression on the base of 

 the ear. 



The general condition of the animal is ver}' seldom affected. Vomit- 

 ing is only observed in exceptional cases; this is said by Froehner to be 

 due to pressure on the auditory branch of the vagus. Vertigo, spasms, 

 and epileptiform convulsions sometimes follow where acari are present 

 in enormous numbers. 



Therapeutic Treatment. — The treatment which corresponds with 

 that of eczema is generally followed. We must thoroughly clean the 

 external ear. This can be done by tying a piece of absorbent cotton or 

 a piece of sponge on the end of one of the ordinary orange sticks used in 

 manicuring (Fig. 157), dipped in alcohol or ether; warm water, made 



Fig. 156. 



Kramer's ear 



speculum. 



