Otitis externa and otitis media in a dog

57 Otitis externa and otitis media in a dog






CASE HISTORY


A detailed history is of paramount importance in understanding the nature of the underlying causes of long-standing otitis externa. It is important to establish the age of onset, seasonality, whether there is evidence of more generalized skin disease or pruritus, and whether there are symptoms of systemic disease. Additional important information is whether the otitis has been unilateral or bilateral, is there aural pruritus or pain, the nature of the aural discharge and whether there are symptoms suggestive of otitis media, such as pain on opening the mouth or neurological signs. Lastly, it is useful to know details of previous treatment and response.


The relevant history in this case was as follows:










CASE WORK-UP


Investigation of both the skin disease and otitis was indicated. Full evaluation of chronic otitis externa involves some or all of the following procedures:







If the ears are painful, general anaesthesia is required to clean and facilitate examination of the ear canals and tympanic membranes. Bulla radiography can be helpful in evaluation of chronic otitis externa and is an aid in deciding whether the ear problem can be managed medically or whether surgery is indicated. The full bulla series consists of ventrodorsal, open-mouth rostrocaudal, lateral, and left and right oblique views. In practice, the first two views usually prove to be the most useful. External ear disease may manifest as calcification of the auricular cartilages and narrowing of the external ear canals. Changes consistent with otitis media include increased density of the air-filled bullae, thickening, lysis or irregularity of the wall of one or both bullae, changes in size and contour, and new bone production. Note that in at least a quarter of cases of otitis media these changes are not present.


A diet trial, intradermal testing and blood work were indicated in this case and, as treatment of the otitis was likely to require glucocorticoid therapy, the decision was made to do intradermal testing at this stage.


The results of the work-up were:













image

Figure 57.4 Ventrodorsal radiograph of the dog in Fig. 57.1. Stenosis of the proximal horizontal ear canals is apparent.


image

Figure 57.5 Rostrocaudal open-mouth radiograph of the dog in Fig. 57.1. The tympanic bullae appear healthy even though there was otitis media.



Stay updated, free articles. Join our Telegram channel

Sep 3, 2016 | Posted by in SMALL ANIMAL | Comments Off on Otitis externa and otitis media in a dog

Full access? Get Clinical Tree

Get Clinical Tree app for offline access